Serotonin and vasovagal syncope.

PURPOSE: The goal of this manuscript was to review the biological and clinical evidence that serotonin neurotransmission might play an important role in the  physiology and treatment of vasovagal syncope. METHODS: The authors reviewed PubMed and handsearches of secondary sources for papers related to the Bezold-Jarisch reflex and serotonin, the plausible involvement of the Bezold-Jarisch reflex in vasovagal syncope, and three lines of clinical evidence involving serotonin and the syncope. RESULTS: The Bezold-Jarisch reflex was first described following the infusion of veratrum alkaloids into animals in the 19th century. The reflex is triggered by serotonin stimulation chemoreceptors and mechanoreceptors in the the left ventricle. The afferent component of the reflex is carried by unmyelinated type C vagal nerve fibers, which results in parasympathetic efferent stimulation that causes bradycardia. The similarity of the combination of hypotension and bradycardia in the Bezold-Jarisch reflex and in vasovagal syncope led to the suggestion that the reflex was the cause of the syndrome.  Three lines of evidence implicate the serotonin 5HT3 receptors in the heart in the reflex. There is genetic and physiologic evidence for the serotonin 5HT1A and 5HT3 receptors and the serotonin reuptake transporter (SERT). Acute blockade of SERT induces vasovagal syncope in humans undergoing head-up tilt table testing, and SERT inhibition reduces hypotension and bradycardia during spinal anaesthesia. Finally, three randomized clinical trials of SERT inhibitors uniformly reported that they significantly reduce the likelihood of vasovagal syncope recurrences. CONCLUSION: Multiple lines of evidence implicate serotonin neurotransmission in the cause of vasovagal syncope.

Deorphanizing an odorant receptor tuned to palm tree volatile esters in the Asian palm weevil sheds light on the mechanisms of palm tree selection.

The Asian palm weevil, Rhynchophorus ferrugineus, is a tremendously important agricultural pest primarily adapted to palm trees and causes severe destruction, threatening sustainable palm cultivation worldwide. The host plant selection of this weevil is mainly attributed to the functional specialization of odorant receptors (ORs) that detect palm-derived volatiles. Yet, ligands are known for only two ORs of R. ferrugineus, and we still lack information on the mechanisms of palm tree detection. This study identified a highly expressed antennal R. ferrugineus OR, RferOR2, thanks to newly generated transcriptomic data. The phylogenetic analysis revealed that RferOR2 belongs to the major coleopteran OR group 2A and is closely related to a sister clade containing an R. ferrugineus OR (RferOR41) tuned to the non-host plant volatile and antagonist, α-pinene. Functional characterization of RferOR2 via heterologous expression in Drosophila olfactory neurons revealed that this receptor is tuned to several ecologically relevant palm-emitted odors, most notably ethyl and methyl ester compounds, but not to any of the pheromone compounds tested, including the R. ferrugineus aggregation pheromone. We did not evidence any differential expression of RferOR2 in the antennae of both sexes, suggesting males and females detect these compounds equally. Next, we used the newly identified RferOR2 ligands to demonstrate that including synthetic palm ester volatiles as single compounds and in combinations in pheromone-based mass trapping has a synergistic attractiveness effect to R. ferrugineus aggregation pheromone, resulting in significantly increased weevil catches. Our study identified a key OR from a palm weevil species tuned to several ecologically relevant palm volatiles and represents a significant step forward in understanding the chemosensory mechanisms of host detection in palm weevils. Our study also defines RferOR2 as an essential model for exploring the molecular basis of host detection in other palm weevil species. Finally, our work showed that insect OR deorphanization could aid in identifying novel behaviorally active volatiles that can interfere with weevil host-searching behavior in sustainable pest management applications.

Incidental Detection of Synchronous Benign Hepatic and Splenic Hemangiomas on 18 F-PSMA PET/CT.

ABSTRACT: A 51-year-old man with biochemical failure after brachytherapy for prostatic adenocarcinoma (PSA 5 µg/L rising to 6.45 µg/L) underwent a PSMA PET/CT scan. The scan revealed focal 18 F-PSMA activity at the right apex suggestive of local residual or recurrent disease. In addition, 18 F-PSMA images demonstrated 2 focal 18 F-PSMA-avid liver and spleen lesions; both lesions were further evaluated by abdominal MRI, and the final radiological diagnosis was synchronous hepatic and splenic hemangiomas.

Family, Individual, and Other Risk Factors Contributing to Risk of Substance Abuse in Young Adults: A Narrative Review.

Substance use disorder and the availability of certain over-the-counter drugs are worldwide issues that affect many individuals, both mentally and physically. As a result, the frequent use of this substance can lead to substance abuse. This phenomenon is also becoming more prevalent with time, and it does not differentiate between genders, ages, races, or religions. This review aimed to provide an overview of studies related to substance abuse, the individuals who tend to abuse these substances, and their risk factors. We also aimed to discuss, identify, and analyze the factors that increase the risk of substance abuse among young adults. We performed a thorough search for related studies using PubMed to provide a comprehensive review of the risk factors and side effects experienced by young adults. The selected indexing terms included "substance abuse,""risk factors," and "personality traits," among others. Information was gathered from relevant peer-reviewed publications, and thereafter refined, and summarized.

The Role of Radiological Imaging in the Diagnosis and Treatment of Urolithiasis: A Narrative Review.

The incidence and prevalence of urolithiasis have been increasing worldwide for the last several decades. This increase could be attributed to many factors, including missed cases of small stones, a sedentary lifestyle, a high BMI, a lack of physical activity, and poor dietary intake. In addition, the increased incidence of co-morbidities such as diabetes, dyslipidemia, infections, and multiple urinary tract surgeries could contribute significantly to the formation of urolithiasis. Radiology has a major role in diagnosing a variety of these stone types and can be used in planning management approaches, either as guidance or as a direct therapeutic method for stones. Because of the availability, safety, cost, and effectiveness of radiological imaging nowadays, urolithiasis is rarely missed; furthermore, the availability of radiological treatment options decreases the need for surgical intervention for urolithiasis, which minimizes hospital stay and surgical-related complications. This review aims to scope and analyze the role of radiological imaging modalities in reaching a diagnosis and planning treatment options for urolithiasis in different circumstances. Information was gathered from relevant peer-reviewed publications in PubMed and thereafter refined and summarized to provide a comprehensive review. The selected indexing terms included "radiological imaging modality," "treatment of urolithiasis," and "diagnosis of urolithiasis," among others.

The negative impact of chronic tobacco smoking on adult neuropsychological function: a cross-sectional study.

BACKGROUND: The evidence on the effects of chronic tobacco smoking on neuropsychological functions is conflicting. The literature remains limited by inconsistent accounting for potentially confounding biomedical and psychiatric conditions. This study aimed to assess the neuropsychological functions of adult chronic tobacco smokers in comparison to group-matched non-smokers. METHOD: The study included 73 smokers and 84 group-matched non-smokers. The data was collected during the year 2019. After an initial interview to collect demographics and smoking profile, the subjects undertook neuropsychological assessments that targeted a wide range of cognitive domains. RESULTS: The performance of smokers was poorer on almost all neuropsychological domains, namely selective attention (p ≤ .001, p = .044), alternating attention (p = .002) working memory (p ≤ .001), Short-term memory (p = .006 and .003), Long-term memory (p ≤ .001), processing accuracy (p ≤ .001), and executive function (p = .011 and .026). Smokers were intact on processing speed. Smoking accumulation and lower age onset of regular smoking were correlated with lower neuropsychological function. CONCLUSION: Our findings add to the growing body of evidence suggesting that chronic tobacco smoking impacts cognition negatively.

The prevalence of malocclusion and orthodontic treatment need of school children in Northern Saudi Arabia.

OBJECTIVE: To evaluate the incidence of malocclusion and requirement for orthodontic treatment in the Saudi region of Hail city. MATERIALS AND METHODS: 520 Saudi participants between 7 and 12 years from Hail city were used in the research, all of whom were selected using a simple randomization method. For every participant, various malocclusion variables such as molar, canine, and incisor relationship, overjet, overbite, open bite, cross bite, scissor cross bite, and the score for the orthodontic treatment need [Index of Orthodontic Treatment Need (IOTN)] were recorded. A light source was used for examination, in addition to mouth mirrors, a calibrated ruler, and a portable dental chair. RESULTS: The prevalence of class I molar relationship was 70.4%, with class II being 21.3% and class III being 8.3%. As for the incisor relationships, class I was found at a prevalence of 72.5%, class II at 19.8%, and class III at 7.7%. Additionally, the following malocclusion characteristics were also found: deep overbite (>4 mm) (16.2%), increased overjet (>4 mm) (14.4%), posterior cross bite (13.3%), anterior open bite (7.7%), anterior cross bite (5.2%), scissor bite (4%), and posterior open bite (0.6%). A total of 4.4% were identified as requiring orthodontic treatment. Grades 1 and 2 were 25.5% and 58.5%, respectively. There was a significant relationship found between grades 3 and 4, and the anterior open bite, cross bite, and scissor bite. CONCLUSION: This research showed that class I malocclusion was most dominant, followed by classes II and III, respectively. When the Hail city school pupils in the study were assessed for IOTN index, grades 3 and 4 were found to be highly related to anterior open bite, cross bite, and scissor bite.

Pseudoankylosis Between Lateral Pterygoid Plates and Mandible: Report of One Case.

Temporomandibular joint (TMJ) ankylosis is the abnormal fusion of TMJ anatomic components that impedes free jaw movements. This restriction in motion ranges from minimal to a complete inability to open the jaw. This condition can be categorized as true ankylosis, which is attributed to pathologic conditions of the TMJ, or false ankylosis (pseudoankylosis), which describes restrictions of movement resulting from extracapsular abnormalities outside the TMJ. The literature shows that trauma is the leading cause of TMJ disorders and appears to be the most common cause of pseudoankylosis. Pseudoankylosis caused by pterygomandibular bony impingement has rarely been reported in the literature. This case report adds a new case of pseudoankylosis to the existing scanty literature, which was characterized by bilateral mechanical impingement between abnormally elongated lateral pterygoid plates and the coronoid processes of the mandible.

Alveolar Osteitis: Patient's Compliance with Post-extraction Instructions Following Permanent Teeth Extraction.

AIM: The study aims to evaluate the patients' compliance with post-extraction instructions to prevent the development of alveolar osteitis and keep the health of the socket. Alveolar osteitis "Dry socket" is considered one of the most common complications after extraction. MATERIALS AND METHODS: Study was based on an observational cross-sectional design involving 201 subjects (individuals). The subjects were evaluated via a survey questionnaire and clinical examination after obtaining their verbal and written consent. The study questionnaire was divided into the following sections; section one records the demographic data about the subject while the second section focuses on self-assessment mainly regarding compliance with post-extraction instructions and pain. RESULTS: A total number of patients included in the study was 201, 122 (60.7%) male and 79 (39.3%) female with an age of more than 18 years. No statistically significant association was reported between a medical condition and dry socket. Out of 201 patients came for clinical examination, 89 felt pain at the site of extraction at different period started from the day of extraction till the day of examination with various pain intensity. Females were the most to feel pain after tooth extraction with 78%. Regarding prevalence, 14 (7%) patients reported having dry socket and poor socket status. A statistically significant association of non-complying patients with the incidence of the dry socket was observed for a wide range of age (18 to 40 years) Conclusion: The study showed a high degree of association between the incidence of dry socket cases for patients with poor compliance with post-extraction instruction. A strong relation was observed between the patients who felt pain and their gender (females) Clinical significance: Based on the findings of the present study, we recommend the need to properly educate patients on the effect of compliance and the various complications and factors affecting the socket status after tooth extraction due to non-compliance.