The role of serotonin in memory: interactions with neurotransmitters and downstream signaling

Abstract Serotonin, or 5-hydroxytryptamine (5-HT), is found to be involved in many physiological or pathophysiological processes including cognitive function. Seven distinct receptors (5-HT1–7), each with several subpopulations, have been identified for serotonin, which are different in terms of localization and downstream signaling. Because of the development of selective agonists and antagonists for these receptors as well as transgenic animal models of cognitive disorders, our understanding of the role of serotonergic transmission in learning and memory has improved in recent years. A large body of evidence indicates the interplay between serotonergic transmission and other neurotransmitters including acetylcholine, dopamine, γ-aminobutyric acid (GABA) and glutamate, in the neurobiological control of learning and memory. In addition,there has been an alteration in the density of serotonergic receptors in aging and Alzheimer’s disease, and serotonin modulators are found to alter the process of amyloidogenesis and exert cognitive-enhancing properties. Here, we discuss the serotonin-induced modulation of various systems involved in mnesic function including cholinergic, dopaminergic, GABAergic, glutamatergic transmissions as well as amyloidogenesis and intracellular pathways

Evaluation of Rigid Ryegrass (Lolium rigidum) accessions for clodinafop-propargyl Resistance using bioassay in Petri dish and pot

Three rigid ryegrass accessions with possible resistance to clodinafop-propargyl, anacetyl-CoA carboxylase (ACCase) inhibitor (group 1) herbicide were identified in Farsprovince fields. Greenhouse studies and seed bioassay experiments were conducted toconfirm clodinafop-propargyl resistance in Lolium rigidum L. In Petri dish seed bioassay testwere determined the coleoptiles length of accessions (as % of untreated control), ID50(dosage required to inhibit coleoptile length by 50%), the degree of resistance in S and Raccessions. In greenhouse experiments to determine the degree of resistance, accessions wereexposed to clodinafop-propargyl at 4-leaf stage. Four weeks after spraying was calculated thedry weight of accessions (%), plant survival of each accession (% of untreated control) andevaluation was performed according to EWRC. Then, the responses of accessions exposed to0.25 to 32 times the recommended dosage of clodinafop-propargyl was measured and thedegree of resistance in S and R accessions was identified. Results of bioassay andgreenhouse studies revealed that in both experiments and for parameters measured FR1accession showed more resistance than the other accessions, followed by FR7 and Saccessions, respectively. So these two methods tested can be used to help assess the degree ofresistance and reached the same result with two methods

Dental caries status and its associated factors in pregnant women, Shiraz, Iran, 2014

BACKGROUND AND AIM: Dental caries is a common problem in pregnant women which has negative impacts on their quality of life. The aim of this study was to evaluate pregnant women’s dental caries status and its associated risk factors in Shiraz, Iran, in 2014. METHODS: In this cross-sectional study, we selected 423 pregnant women attending Shiraz governmental health centers for routine obstetric examinations by randomized cluster sampling. The women's dental caries status was assessed using decayed, missed, and filled tooth (DMFT) index. The women’s demographic characteristics and their oral hygiene habits were evaluated using a valid and reliable questionnaire. The relationship between women's DMFT index and their demographic and oral hygiene characteristics was evaluated using Pearson correlation, analysis of variance, independent sample t-tests, and multiple linear regression models. RESULTS: The mean DMFT index was 5.8 ± 3.6. We found lower scores of DMFT index in women who were younger (P < 0.001), brushed their teeth more (P = 0.014), and used home preventive measures such as mouthwash (P = 0.003) and toothpick (P = 0.006). CONCLUSION: Dental caries status of the pregnant women was unacceptably lower than optimal. Interventions focusing on holding educational programs and taking office-based preventive measures for pregnant women or women who intend to be pregnant are recommended. The interventions are more necessary for older pregnant women and those who use fewer home preventive measures. KEYWORDS: Dental Caries; Iran; Pregnanc

i-SNAREs: inhibitory SNAREs that fine-tune the specificity of membrane fusion

A new functional class of SNAREs, designated inhibitory SNAREs (i-SNAREs), is described here. An i-SNARE inhibits fusion by substituting for or binding to a subunit of a fusogenic SNAREpin to form a nonfusogenic complex. Golgi-localized SNAREs were tested for i-SNARE activity by adding them as a fifth SNARE together with four other SNAREs that mediate Golgi fusion reactions. A striking pattern emerges in which certain subunits of the cis-Golgi SNAREpin function as i-SNAREs that inhibit fusion mediated by the trans-Golgi SNAREpin, and vice versa. Although the opposing distributions of the cis- and trans-Golgi SNAREs themselves could provide for a countercurrent fusion pattern in the Golgi stack, the gradients involved would be strongly sharpened by the complementary countercurrent distributions of the i-SNAREs

Dental caries status and its associated factors in pregnant women, Shiraz, Iran, 2014

BACKGROUND AND AIM: Dental caries is a common problem in pregnant women which has negative impacts on their quality of life. The aim of this study was to evaluate pregnant women’s dental caries status and its associated risk factors in Shiraz, Iran, in 2014. METHODS: In this cross-sectional study, we selected 423 pregnant women attending Shiraz governmental health centers for routine obstetric examinations by randomized cluster sampling. The women's dental caries status was assessed using decayed, missed, and filled tooth (DMFT) index. The women’s demographic characteristics and their oral hygiene habits were evaluated using a valid and reliable questionnaire. The relationship between women's DMFT index and their demographic and oral hygiene characteristics was evaluated using Pearson correlation, analysis of variance, independent sample t-tests, and multiple linear regression models. RESULTS: The mean DMFT index was 5.8 ± 3.6. We found lower scores of DMFT index in women who were younger (P < 0.001), brushed their teeth more (P = 0.014), and used home preventive measures such as mouthwash (P = 0.003) and toothpick (P = 0.006). CONCLUSION: Dental caries status of the pregnant women was unacceptably lower than optimal. Interventions focusing on holding educational programs and taking office-based preventive measures for pregnant women or women who intend to be pregnant are recommended. The interventions are more necessary for older pregnant women and those who use fewer home preventive measures

SARS-CoV-2 and Acute Cerebrovascular Events: An Overview

Since the coronavirus disease 2019 (COVID-19) pandemic, due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, accumulating evidence indicates that SARS-CoV-2 infection may be associated with various neurological manifestations, including acute cerebrovascular events (i.e., stroke and cerebral venous thrombosis). These events can occur prior to, during and even after the onset of COVID-19\u27s general symptoms. Although the mechanisms underlying the cerebrovascular complications in patients with COVID-19 are yet to be fully elucidated, the hypercoagulability state, inflammation and altered angiotensin-converting enzyme 2 (ACE-2) signaling in association with SARS-CoV-2 may play key roles. ACE-2 plays a critical role in preserving heart and brain homeostasis. In this review, we discuss the current state of knowledge of the possible mechanisms underlying the acute cerebrovascular events in patients with COVID-19, and we review the current epidemiological studies and case reports of neurovascular complications in association with SARS-CoV-2, as well as the relevant therapeutic approaches that have been considered worldwide. As the number of published COVID-19 cases with cerebrovascular events is growing, prospective studies would help gather more valuable insights into the pathophysiology of cerebrovascular events, effective therapies, and the factors predicting poor functional outcomes related to such events in COVID-19 patients

Identification of viruses infecting cucurbits and determination of genetic diversity of Cucumber mosaic virus in Lorestan province, Iran

Various viral pathogens infect Cucurbitaceae and cause economic losses. Th e aim of the present study was to detect plant viral pathogens including Cucumber mosaic virus (CMV), Cucumber green mottle mosaic virus (CGMMV), Zucchini yellow mosaic virus (ZYMV), Cucurbit yellow stunting disorder virus (CYSDV) and Cucurbit chlorotic yellows virus (CCYV) in Lorestan province, in western Iran, and also to determine CMV genetic diversity in Iranian populations. A total of 569 symptomatic leaf samples were collected in 2013 and 2014 from cucurbits growing regions in Lorestan province. Th e collected samples were assessed for viral diseases by ELISA. Th e results showed virus incidences in most regions. Th en, the infection of 40 samples to CMV was confi rmed by RT-PCR. Moreover, to distinguish between the two groups (I and II) of CMV, PCR products were digested by two restriction enzymes XhoI and EcoRI. Results of the digestion showed that the isolates of Lorestan belonged to group I. Th e CMV-coat protein gene of eight isolates from diff erent regions and hosts was sequenced and phylogenetic analysis was performed. Subsequent analyses showed even more genetic variation among Lorestan isolates. Th e phylogenetic tree revealed that Lorestan province isolates belonged to two IA and IB subgroups and could be classifi ed together with East Azerbaijan province isolates. Th e results of the present study indicate a wide distribution of CMV, ZYMV, CGMMV, CYSDV and CCYV viruses in cucurbits fi elds of Lorestan province and for the fi rst time subgroup IB of CMV was reported on melon from Iran