Dizziness in peri- and postmenopausal women is associated with anxiety: a cross-sectional study

Background

Although dizziness is one of the most common symptoms of menopause, the underlying mechanism is not precisely known. Therefore, this study aimed to investigate the prevalence of, and the factors associated with, dizziness in peri- and postmenopausal women.

Methods

We conducted a cross-sectional study in which we analyzed the first-visit records of 471 Japanese women aged 40 to 65?years who enrolled in a health and nutrition education program at a menopause clinic. The prevalence of dizziness was estimated according to the participants’ responses to the Menopausal Health-Related Quality of Life Questionnaire. The background characteristics of age, menopause status, body composition, cardiovascular parameters, basal metabolism, and physical fitness; other menopausal symptoms, including vasomotor, insomnia, depression, and anxiety symptoms; and lifestyle characteristics were assessed for their associations with dizziness.

Results

The percentage of women who suffered from dizziness once a week or more frequently was 35.7%. Compared to the women without dizziness, those with the symptom were younger; had a higher body weight, body mass index, body fat percentage, muscle mass, and waist-to-hip ratio; had higher systolic pressure; were slower in reaction time; had higher physical and psychological symptom scores of menopause; exercised less regularly; and consumed less alcohol. A multivariate logistic regression analysis revealed that the anxiety symptom, which was evaluated by the Hospital Anxiety and Depression Scale, was the sole factor that was independently associated with dizziness (adjusted odds ratio 1.14; 95% confidence interval 1.08–1.20).

Conclusions

Dizziness is highly prevalent in Japanese peri- and postmenopausal women and it is associated with anxiety. The treatment of anxiety in this population might improve the symptom.

     

A Sialylated Voltage-Dependent Ca2+ Channel Binds Hemagglutinin and Mediates Influenza A Virus Entry into Mammalian Cells

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Enhancement of hypocotyl elongation by LOV KELCH PROTEIN2 production is mediated by auxin and phytochrome-interacting factors in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

Key message

Auxin and two phytochrome-interacting factors, PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PIF5, play crucial roles in the enhancement of hypocotyl elongation in transgenic Arabidopsis thaliana plants that overproduce LOV KELCH PROTEIN2 (LKP2).

Abstract

LOV KELCH PROTEIN2 (LKP2) is a positive regulator of hypocotyl elongation under white light in Arabidopsis thaliana. In this study, using microarray analysis, we compared the gene expression profiles of hypocotyls of wild-type Arabidopsis (Columbia accession), a transgenic line that produces green fluorescent protein (GFP), and two lines that produce GFP-tagged LKP2 (GFP-LKP2). We found that, in GFP-LKP2 hypocotyls, 775 genes were up-regulated, including 36 auxin-responsive genes, such as 27 SMALL AUXIN UP RNA (SAUR) and 6 AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) genes, and 21 genes involved in responses to red or far-red light, including PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PIF5; and 725 genes were down-regulated, including 15 flavonoid biosynthesis genes. Hypocotyls of GFP-LKP2 seedlings, but not cotyledons or roots, contained a higher level of indole-3-acetic acid (IAA) than those of control seedlings. Auxin inhibitors reduced the enhancement of hypocotyl elongation in GFP-LKP2 seedlings by inhibiting the increase in cortical cell number and elongation of the epidermal and cortical cells. The enhancement of hypocotyl elongation was completely suppressed in progeny of the crosses between GFP-LKP2 lines and dominant gain-of-function auxin-resistant mutants (axr2-1 and axr3-1) or loss-of-function mutants pif4, pif5, and pif4 pif5. Our results suggest that the enhancement of hypocotyl elongation in GFP-LKP2 seedlings is due to the elevated level of IAA and to the up-regulated expression of PIF4 and PIF5 in hypocotyls.

     

Molecular cloning and expression of human neurochondrin-1 and -2.

Human neurochondrins have been cloned from a brain cDNA library. The human neurochondrin-1 and -2 predict leucine-rich (15.8 and 15.9%) proteins of 729 and 712 amino acid residues, with molecular weights of 78.9 and 77.2 kDa, respectively. The deduced amino acid sequence indicates 98% identity among human, mouse and rat species. Northern analysis indicates that about 4 kb human neurochondrin mRNAs are abundant in the fetal and the adult brain.     

The expression of tobacco knotted1-type class 1 homeobox genes correspond to regions predicted by the cytohistological zonation model

We have isolated and characterized four tobacco homeobox genes, NTH1, NTH9, NTH20, NTH22 (Nicotiana tabacum homeobox) which belong to the class 1 knotted1-type family of homeobox genes. Comparison of the inferred amino acid sequences of the ELK homeodomains of these genes and previously reported kn1-type class 1 proteins has revealed that the four new tobacco genes belong to distinct subclasses, suggesting that each NTH gene may have distinct functions. Using in situ hybridization and by analysing the distribution of GUS activity in tobacco plants transformed with NTH promoter::GUS constructs, localized expression of the three NTH genes was observed in the shoot apical meristem (SAM). In the vegetative SAM, NTH1 and NTH15 showed overlapping expression in the corpus, NTH20 was expressed in the peripheral zone, and NTH9 was predominantly expressed in the rib zone. The expression patterns of the different NTH genes correspond to regions predicted by the cytohistological zonation model, suggesting that each NTH gene specifies the function of the SAM zone with which it is associated.     

Basic fibroblast growth factor induces osteoclast formation by reciprocally regulating the production of osteoclast differentiation factor and osteoclastogenesis inhibitory factor in mouse osteoblastic cells.

Basic fibroblast growth factor (bFGF) induced osteoclast formation in co-cultures of mouse spleen cells and osteoblasts. Osteoclastogenesis inhibitory factor (OCIF) and a selective cyclooxygenase-2 (COX-2) inhibitor, NS-398, abolished bFGF-induced osteoclast formation. bFGF did not affect spleen cells, but it did affect osteoblasts, to stimulate osteoclast formation. Northern blot analysis revealed that bFGF up-regulated the expression of osteoclast differentiation factor (ODF) and COX-2 and down-regulated the expression of OCIF in primary osteoblastic cells. NS-398 abolished the increase of ODF mRNA, but it had no effect on the decrease of OCIF mRNA. NS-398 suppressed the binding of (125)I-labeled OCIF to osteoblastic cells treated with bFGF. Enzyme-linked immunosorbent assay showed that bFGF inhibited OCIF production by osteoblastic cells, and the inhibition was not affected by NS-398. We conclude that bFGF induces osteoclast formation by stimulating ODF production through COX-2-mediated prostaglandin synthesis and by suppressing OCIF production through a mechanism independent of prostaglandin synthesis.     

Activation of C3G guanine nucleotide exchange factor for Rap1 by phosphorylation of tyrosine 504.

C3G is a guanine nucleotide exchange factor for Rap1 and is activated by the expression of Crk adaptor proteins. We found that expression of CrkI in COS cells induced significant tyrosine phosphorylation of C3G. To understand the mechanism by which C3G is phosphorylated and activated by Crk, we constructed a series of deletion mutants. Deletion of the amino terminus of C3G to amino acid 61 did not remarkably affect either tyrosine phosphorylation or Crk-dependent activation of C3G. When C3G was truncated to amino acid 390, C3G was still phosphorylated on tyrosine but was not effectively activated by CrkI. Deletion of the amino terminus of C3G to amino acid 579 significantly reduced the Crk-dependent tyrosine phosphorylation of C3G and increased GTP-bound Rap1 irrespective of the presence of CrkI. We substituted all seven tyrosine residues in this region, amino acids 391-579, for phenylalanine for identification of the phosphorylation site. Among the substitution mutants, the C3G-Y504F mutant, in which tyrosine 504 was substituted by phenylalanine, was remarkably less activated and phosphorylated than the wild type. All the other substitution mutants were activated and tyrosyl-phosphorylated by the expression of CrkI. Thus, CrkI activates C3G by the phosphorylation of tyrosine 504, which represses the cis-acting negative regulatory domain outside the catalytic region.     

Crystal structure of human serum albumin at 2.5 A resolution.

A new triclinic crystal form of human serum albumin (HSA), derived either from pool plasma (pHSA) or from a Pichia pastoris expression system (rHSA), was obtained from polyethylene glycol 4000 solution. Three-dimensional structures of pHSA and rHSA were determined at 2.5 A resolution from the new triclinic crystal form by molecular replacement, using atomic coordinates derived from a multiple isomorphous replacement work with a known tetragonal crystal form. The structures of pHSA and rHSA are virtually identical, with an r.m. s. deviation of 0.24 A for all Calpha atoms. The two HSA molecules involved in the asymmetric unit are related by a strict local twofold symmetry such that the Calpha atoms of the two molecules can be superimposed with an r.m.s. deviation of 0.28 A in pHSA. Cys34 is the only cysteine with a free sulfhydryl group which does not participate in a disulfide linkage with any external ligand. Domains II and III both have a pocket formed mostly of hydrophobic and positively charged residues and in which a very wide range of compounds may be accommodated. Three tentative binding sites for long-chain fatty acids, each with different surroundings, are located at the surface of each domain.     

Production of bleomycin N-acetyltransferase in Escherichia coli and Streptomyces verticillus

Bleomycin-producing Streptomyces verticillus ATCC 15003 has two bleomycin resistance genes, designated blmA and blmB. Bleomycin N-acetyltransferase, encoded by blmB, was overproduced in Escherichia coli as a protein fused to the maltose-binding protein. The protein (fBAT), purified to homogeneity after digestion of the fusion product with blood coagulation factor X_a protease, had an additional 6 N-terminal amino acid residues, but retained its bleomycin-acetylating activity, as did the entire fusion protein. The K_m and V_max values of purified fBAT for the substrate bleomycin were 13.0 μM and 3.4 pmol min⁻¹ ml⁻¹, respectively. The optimal pH for the acetylating activity was 6.0 in 10 mM phosphate buffer. The molecular mass and pI value of fBAT were estimated by polyacrylamide gel electrophoresis to be about 34 500 and 6.13, respectively. An anti-fBAT monoclonal antibody was generated and used to show that bleomycin N-acetyltransferase is expressed simultaneously with bleomycin production in S. verticillus.     

Practical methods for handling human periodontal ligament stem cells in serum-free and serum-containing culture conditions under hypoxia: implications for regenerative medicine

Stem cell-based therapies depend on the reliable expansion of patient-derived mesenchymal stem cells (MSCs) in vitro. The supplementation of cell culture media with serum is associated with several risks; accordingly, serum-free media are commercially available for cell culture. Furthermore, hypoxia is known to accelerate the expansion of MSCs. The present study aimed to characterize the properties of periodontal ligament-derived MSCs (PDLSCs) cultivated in serum-free and serum-containing media, under hypoxic and normoxic conditions. Cell growth, gene and protein expression, cytodifferentiation potential, genomic stability, cytotoxic response, and in vivo hard tissue generation of PDLSCs were examined. Our findings indicated that cultivation in serum-free medium does not affect the MSC phenotype or chromosomal stability of PDLSCs. PDLSCs expanded in serum-free medium exhibited more active growth than in fetal bovine serum-containing medium. We found that hypoxia does not alter the cell growth of PDLSCs under serum-free conditions, but inhibits their osteogenic and adipogenic cytodifferentiation while enabling maintenance of their multidifferentiation potential regardless of the presence of serum. PDLSCs expanded in serum-free medium were found to retain common MSC characteristics, including the capacity for hard tissue formation in vivo. However, PDLSCs cultured in serum-free culture conditions were more susceptible to damage following exposure to extrinsic cytotoxic stimuli than those cultured in medium supplemented with serum, suggesting that serum-free culture conditions do not exert protective effects against cytotoxicity on PDLSC cultures. The present work provides a comparative evaluation of cell culture in serum-free and serum-containing media, under hypoxic and normoxic conditions, for applications in regenerative medicine.