[Changes of serum E2 and Otolin-1 levels in postmenopausal women with BPPV]

Objective:To investigate the changes of serum estradiol（E2） and otolith structural protein Otolin-1 levels in postmenopausal women with benign paroxysmal positional vertigo（BPPV）. Method:Forty postmenopausal women diagnosed as primary BPPV were selected as the experimental group. Meanwhile, 40 postmenopausal women without vertigo during the same time were selected as the control group. 4 ml of fasting peripheral venous blood was extracted in the morning, and E2 and Otolin-1 protein levels in serum of the two groups were detected by electrochemiluminescence（ECL） and ELISA, respectively. Result:①The serum level of E2 in the experimental group was（29.11±15.11） pg/ml, which was lower than that in the control group（37.18±12.24） pg/ml（P=0.010）. ②The serum level of Otolin-1 in the experimental group was（361.55±186.14） pg/ml, which was significantly higher than that in the control group（282.61±139.98） pg/ml（P=0.035）. ③Spearman correlation analysis was carried out on the serum levels of Otolin-1 and E2 in the experimental group and the control group, respectively, and no correlation was found between them（P=0.403 and 0.363, respectively）. ④In the control group, age was negatively correlated with serum E2 level（P=0.044, r=-0.320）, suggesting that age was only weakly correlated with E2 level. However, in the experimental group, there was no correlation between the two（P=0.148）. ⑤There was no correlation between age and serum Otolin-1 level in the two groups（P=0.705 and 0.076, respectively）. Conclusion:Compared with postmenopausal patients without vertigo, the level of E2 in postmenopausal BPPV patients decreased, but the level of Otolin-1 increased significantly. Therefore, the serum level of Otolin-1 may be used as a bio-marker to assist the diagnosis and efficacy evaluation of postmenopausal women with BPPV.

[Etiological analysis on patients in department of vertigo and dizziness oriented outpatient]

Objective: We aimed to explore the spectrum of causes for patients in department of vertigo and dizziness oriented outpatient, in order to provide a reference for diagnosis and treatment of patients with vertigo or dizziness. Methods: Retrospective analysis were carried out with clinical data of patients in our department of vertigo and dizziness oriented outpatient. The target group under study was diagnosed based on the uniform diagnostic criteria, and re-visiting patients were excluded. Results: This clinical study was conducted on 5 348 cases, who visited our vertigo and dizziness oriented outpatient from December 2012 to July 2015. The ratio of male to female was 1∶1.48, the age range was between 16 and 93. The frequencies of different etiology were: benign paroxysmal positional vertigo 1 902(35.56%), Chronic subjective dizziness 1 329(24.85%), vestibular migraine 624(11.67%), Meniere's disease 378(7.07%), multi-sensory neuropathy 231(4.32%), vestibular paroxysmia 177(3.31%), benign recurrent vestibulopathy 171(3.20%), presyncope 66(1.23%), posterior circulation ischemia 57(1.07%), vestibular neuritis 54(1.01%), sudden deafness complicated vertigo 36(0.67%), other reasons 68(1.27%), unknown 255(4.77%). Conclusions: Our study indicates that the precedent three causes for vertigo or dizziness are benign paroxysmal positional vertigo, chronic subjective dizziness and vestibular migraine, followed by Meniere's disease、multi-sensory neuropathy, vestibular paroxysmia and benign recurrent vestibulopathy. Presyncope, posterior circulation ischemia, vestibular neuritis and sudden deafness complicated vertigo are relatively infrequent. There are still a certain proportion of patients undetermined.

[Misdiagnosis and associated costs of benign paroxysmal positional vertigo]

Objective: The aims of this study were to investigate the misdiagnosis of benign paroxysmal positional vertigo (BPPV) and to estimate the associated costs. Methods: During October 2015 to December 2015, eighty patients were diagnosed with BPPV in the outpatient dizziness clinic of Shanghai Changzheng Hospital and the clinical data of all the 80 patients were collected including the demographic and clinical characteristics, the history of diagnosis, inappropriate diagnostic tests, costs of the medical tests, transportation and accommodation. All the data were investigated to estimate the misdiagnosis of benign paroxysmal positional vertigo and the associated costs in Shanghai, China. Results: This study showed that the misdiagnosis rate of BPPV was 60.0% (48/80) and the common inappropriate diagnostic tests for BPPV included Cranial CT and MRI test, cervical MRI, cervical and cerebrovascular investigations et al. There was no significant difference between the misdiagnosis patients (48) and patients without misdiagnosis (32) in gender, age, duration of symptom, involved canal and type of BPPV.Complications were significantly more frequent in the misdiagnosis group than for those without[81.3%(39 /48) vs 34.4%(11 /32)]. The estimated costs for each misdiagnosed individual were 8 502.98 China Yuan (CNY) and one-year economic burden associated with the misdiagnosis of BPPV in Shanghai was 13.184 7-78.862 1 million CNY. Conclusions: Our study suggests that the misdiagnosis rate of BPPV is high and the financial impact on patients and society with this disease is huge. The cost-effective Dix-Hallpike or supine roll test maneuver should be used before applying other expensive medical tests in order to minimize misdiagnosis and the waste of health care resources.

Comparative transcriptome analysis of self-incompatible flower stigmas and self-compatible bud stigmas following self-pollination in broccoli

DH07 is a DH line of Class I S-haplotype in broccoli (Brassica oleracea var. italica), in which stigmas of flowers show self-incompatibility (SI) and stigmas of buds show self-compatibility (SC). The molecular mechanisms that lead to stigmas at different developmental stages having different responses to self-pollination are yet unknown. In the present study, comparative transcriptome profiling of the stigmas of flowers and buds before and after self-pollination was performed by RNA-sequencing using an Illumina HiSeq^TM 2000. A total of 80,102,897 reads were generated for further analysis in four libraries. Comparisons of the transcriptome profiles before and after self-pollination revealed 579 differentially expressed genes (DEGs) in the stigmas of buds (SBs); of these, 431 DEGs showed increased and 148 DEGs showed decreased transcript abundance after self-pollination in SBs. There were a total of 686 DEGs between unpollinated stigmas of flowers (SFs) and pollinated SFs, among which, 517 DEGs were up regulated and 169 DEGs were down regulated. Following the self-pollination, 379 identified DEGs were common in both SBs and SFs. It was found that ARR7-like and oxysterol-binding family protein related DEGs could play key roles in SI or SC signal transduction. The results obtained in this study would form the foundation for further studies on investigating the molecular mechanisms of SI and SC in Brassica.

In-depth analysis of internal control genes for quantitative real-time PCR in Brassica oleracea var. botrytis

Quantitative reverse-transcription PCR (qRT-PCR) is a versatile technique for the analysis of gene expression. The selection of stable reference genes is essential for the application of this technique. Cauliflower (Brassica oleracea L. var. botrytis) is a commonly consumed vegetable that is rich in vitamin, calcium, and iron. Thus far, to our knowledge, there have been no reports on the validation of suitable reference genes for the data normalization of qRT-PCR in cauliflower. In the present study, we analyzed 12 candidate housekeeping genes in cauliflower subjected to different abiotic stresses, hormone treatment conditions, and accessions. geNorm and NormFinder algorithms were used to assess the expression stability of these genes. ACT2 and TIP41 were selected as suitable reference genes across all experimental samples in this study. When different accessions were compared, ACT2 and UNK3 were found to be the most suitable reference genes. In the hormone and abiotic stress treatments, ACT2, TIP41, and UNK2 were the most stably expressed. Our study also provided guidelines for selecting the best reference genes under various experimental conditions.

Cocaine produces conditioned place aversion in mice with a cocaine-insensitive dopamine transporter

Cocaine is an inhibitor of the dopamine, norepinephrine and serotonin reuptake transporters. Because its administration would elevate signaling of all these three neurotransmitters, many studies have been aimed at attributing individual effects of cocaine to specific transmitter systems. Using mice with a cocaine-insensitive dopamine transporter (DAT-CI mice), we previously showed that cocaine-induced dopamine elevations were necessary for its rewarding and stimulating effects. In this study, we observe that DAT-CI mice exhibit cocaine-conditioned place aversion (CPA), and that its expression depends on their genetic background. Specifically, DAT-CI mice backcrossed to the C57Bl/6J strain background did not display a preference or an aversion to cocaine, whereas DAT-CI mice that were on a mixed 129S1/SvImJ × C57Bl/6J (129B6) background had a robust CPA to cocaine. These results indicate that while inhibition of the DAT is necessary for cocaine reward, other cocaine targets and neurotransmitter systems may mediate the aversive properties of cocaine. Furthermore, the aversive effect of cocaine can be observed in the absence of a DAT-mediated rewarding effect, and it is affected by genomic differences between these two mouse strains.

The NH(2)-terminus of norepinephrine transporter contains a basolateral localization signal for epithelial cells

When expressed in epithelial cells, dopamine transporter (DAT) was detected predominantly in the apical plasma membrane, whereas norepinephrine transporter (NET) was found in the basolateral membrane, despite 67% overall amino acid sequence identity. To identify possible localization signals responsible for this difference, DAT-NET chimeras were expressed in MDCK cells and localized by immunocytochemistry and transport assays. The results suggested that localization of these transporters in MDCK cells depends on their highly divergent NH(2)-terminal regions. Deletion of the first 58 amino acids of DAT (preceding TM1) did not change its apical localization. However, the replacement of that region with corresponding sequence from NET resulted in localization of the chimeric protein to the basolateral membrane, suggesting that the NH(2)-terminus of NET, which contains two dileucine motifs, contains a basolateral localization signal. Mutation of these leucines to alanines in the context of a basolaterally localized NET/DAT chimera restored transporter localization to the apical membrane, indicating that the dileucine motifs are critical to the basolateral localization signal embodied within the NET NH(2)-terminal region. However, the same mutation in the context of wild-type NET did not disrupt basolateral localization, indicating the presence of additional signals in NET directing its basolateral localization within the plasma membrane.

[Epstein-Barr virus latent membrane protein 1 induces the telomerase activity in human nasopharyngeal epithelial cells]

Telomerase activation has been linked to cell immortalization in vitro and tumorigenicity in vivo. In this study, for the first, we reported that Epstein-Barr virus activated the telomerase activity of human nasopharyngeal epithelial cells in the early stage of immortalization as tested by the PCR-ELISA. The telomerase activity in nasopharyngeal epithelial cells was only observed in presenescent cells. It was implicated that Epstein-Barr virus induced the escape of nasopharyngeal epithelial cells from senescence via the activation of telomerase. We further showed that telomerase activation in infected cells was dependent on the protein level of latent membrane protein 1 (LMP1) encoded by Epstein-Barr virus using a Tetracycline regulatory cell line expressing LMP1, pTet-on-LMP1-HNE2. The activity of telomerase in nasopharyngeal cells was decreased when the protein level of LMP1 was blocked by antisense LMP1 plasmid DNA. And the activity of telmerase was also related to the carboxyl terminus of LMP1. It was implicated that the ability of Epstein-Barr virus to suppress senescence is associated with telomerase activation by LMP1.

[Observation of the biological characterizations of nasopharyngeal epithelial cells by EB virus infection in early phase of immortalization]

The multi-stage cell model of the nasopharyngeal carcinoma development in vitro by Epstein-Barr virus transformation is beneficial for the elucidation of the mechanism of nasopharyngeal cancer. To observe the biological changes of primary human nasopharyngeal epithelial cells in early phase of immortalization, in this study, we have detected the morphological changes and the expression profile of senescence-associated beta-galactosidase (SA-beta-Gal) in primary culture. In addition, the expression of EB virus latent membrane protein 1 (LMP1) and the growth curve of primary cells were also detected. Our results showed a low percentage of cells infected with EB virus expressing SA-beta-Gal activity at the late primary culture. In morphology, the cells also formed multilayer foci, and the cell population doubling time was showed. These results demonstrated that the nasopharyngeal epithelial cells by EB virus infection have passed through the senescence and entered the early phase of immortalization. These cells have some of the transformed characteristics. Our results provided the data for further study on the mechanism of immortalization and the establishment of human nasopharyngeal epithelial cell line.

Dilution enhancement of COS cell expression cloning

To search for an efficient expression cloning method, we mixed plasmid pmDATsv, which contains the mouse dopamine transporter (mDAT) cDNA, with a large amount of another plasmid prGlyTsv to mimic the situation of a cDNA library and examined COS cell expression. Both plasmids have an SV40 replication origin and thus will be replicated to high copy numbers in COS cells. After transfecting COS-7 cells with pmDATsv/prGlyTsv mixture at 1/1000 ratio, we could not detect any cells expressing strong mDAT activity. In contrast, when prGlyTsv was replaced by prSERTsk (no SV40 origin) in the transfection mixture, we observed hundreds of cells expressing strong mDAT activity. The results suggested that in many cells low mDAT expression was not due to the lack of pmDATsv plasmid but due to the presence of large numbers of replicable prGlyTsv. Analysis with a mathematical model suggests that diluting cDNA libraries with other plasmids without the SV40 origin should improve the detection of COS cells expressing target cDNAs. We tested this conclusion with pmDATsv/prGlyTsv mixture. When the mixture at 1/1000 ratio was diluted with prSERTsk and used for transfection, we could now easily detect cells expressing strong mDAT activity.

Molecular cloning of the mouse dopamine transporter and pharmacological comparison with the human homologue

Drug abuse is a serious problem in the United States and in the world. Cocaine and amphetamines, widely used drugs of abuse, bind to dopamine (DA), serotonin, and norepinephrine transporters with high affinity and block their functions. It is believed that the dopamine transporter plays a key role in the mechanism of cocaine addiction. Because a good portion of our knowledge about drug addiction is derived from studying mouse as an animal model, it is essential to compare the properties of dopamine transporter from human and mouse. We report here the cloning of the mouse dopamine transporter (mDAT) cDNA and its expression and comparison with the human DAT. The 3.4 kilobase (kb) cDNA encodes a polypeptide that is 93.5% identical to the hDAT, with 619 amino acid residues and a calculated molecular weight of 68.8kDa. Dopamine transporters from mouse and human were stably expressed in the same parental MDCK cells and their properties were compared. The Michaelis-Menten constant Km values are 2.0 microM for mDAT and 2.4 microM for hDAT. Mouse and human DAT were also compared for drug inhibition profiles. Dopamine transporters from the two species have the same sensitivity to amphetamine (Kd: 0.75 microM) and bupropion (Kd: 1.5 microM). However, hDAT is more sensitive than mDAT to cocaine (Kd: 0.14 microM and 0. 29 microM respectively) and to ritalin (Kd: 0.038 microM and 0. 12 microM respectively). The cloning of mDAT cDNA provides an important tool for further study of the mechanism of drug addiction using mouse as an animal model.

Cell-specific sorting of biogenic amine transporters expressed in epithelial cells

We have utilized polarized epithelial cells stably expressing neurotransmitter transporters to analyze the sorting behavior of these membrane proteins. The transporters for serotonin (5-HT), dopamine (DA), and norepinephrine (NE) are expected to be present in situ in the most distal extremities of axonal membranes, where they terminate the action of their biogenic amine substrates. Both Madin-Darby canine kidney (MDCK) and LLC-PK1 cells were stably transfected with cDNAs encoding either the rat 5-HT transporter (SERT), the human NE transporter (NET), or the rat or human DA transporter (DAT). These cells were grown on permeable filter supports, and the transporters were localized by three independent techniques. Confocal immunofluorescence microscopy indicated that each of the transporters expressed in LLC-PK1 cells was sorted to the basolateral membrane, co-localizing with the Na+/K+-ATPase. In MDCK cells, however, DAT was located primarily on the apical surface, while SERT and NET were found on the basolateral membranes. Cell surface biotinylation using an impermeant biotinylating reagent confirmed the immunocytochemistry results. Thus, SERT and NET in MDCK cells were labeled more efficiently from the basolateral medium than the apical medium, and DAT in MDCK cells was labeled more efficiently from the apical side than the basolateral side. Transport measurements in transfected MDCK cells agreed with the immunocytochemistry and biotinylation results. These results suggest the existence of cell-specific mechanisms that discriminate between neurotransmitter transporters for surface expression and render unlikely any simple hypothesis that sorting mechanisms in neurons and epithelia are identical.

Ion coupling stoichiometry for the norepinephrine transporter in membrane vesicles from stably transfected cells

We prepared membrane vesicles from stable LLC-PK1 cells expressing serotonin (5-HT) gamma-aminobutyric acid (GABA) and norepinephrine (NE) transporters (SERT, GAT-1, and NET). These vesicles accumulate transport substrates when the appropriate transmembrane ion gradients are imposed. For NET, accumulation of [3H]dopamine (DA) was stimulated by imposition of Na+ and Cl- gradients (out > in) and of a K+ gradient (in > out). The presence of Na+ or Cl-, even in the absence of a gradient, stimulated DA accumulation by NET, but K+ had little or no effect in the absence of a K+ gradient. Stimulation by a K+ gradient was markedly enhanced by increasing the K+ permeability with valinomycin, suggesting that net positive charge is transported together with DA. Cationic DA is likely to be the major substrate for NET, since varying pH did not affect Km. We estimated the Na+:DA stoichiometry by measuring the effect of the transmembrane Na+ gradient on peak DA accumulation. The results suggest a 1:1 cotransport of Na+ with DA. Taken together, the results suggest that NET catalyzes cotransport of one cationic substrate molecule with one Na+ ion, and one Cl- ion, and that K+ does not participate directly in the transport process.

Saccharomyces cerevisiae expression of exogenous vacuolar ATPase subunits B

The precise function of subunit B of the vacuolar H(+)-ATPase class is unknown, but it is essential for proton pumping. We have previously reported the DNA sequence and predicted protein sequence of the vacuolar ATPase subunit B for Candida tropicalis (Gu, H.H., Gallagher, M.J., Rupkey, S. and Dean, G.E. (1990) Nucleic Acids Res. 18, 7446). When the Candida gene was expressed in a Saccharomyce cerevisiae delta vat2 mutant from which the homologous gene had been deleted, viability and vacuolar acidification was restored to apparently wild-type levels. The predicted identity between these two proteins is 90%. We have searched for vacuolar ATPase subunits B from other species that might show a difference in function, when expressed in yeast, relative to the endogenous gene. We have cloned an apparently full-length 1.8-kb bovine subunit B cDNA from adrenal medulla that is about 1 kb shorter than the previously reported bovine brain cDNA (Puopolo, K., Kumamoto, C., Adachi, I., Magner, R. and Forgac, M. (1992) J. Biol. Chem. 267, 3696-3706; Nelson, R.D., Guo, X.L., Masood, K., Brown, D., Kalkbrenner, M. and Gluck, S. (1992) Proc. Natl. Acad. Sci. USA 89, 3541-3545), but nearly identical throughout the coding nucleotide and protein sequences; it is only 74% identical to the Saccharomyces subunit B protein sequence. Upon expression of this cDNA in two different delta vat2 deletion strains, the bovine cDNA restored function only partially, as judged by both viability at high pH and vacuolar acidification. Current work is aimed at determining which regions of the bovine protein require alteration in order to fully restore the delta vat2 strain to wild-type acidification, with the eventual goal of identifying interactive residues between subunit B and other proteins required for pump function.

Peptide splicing in the vacuolar ATPase subunit A from Candida tropicalis

Subunit A of the vacuolar proton pump appears to be responsible for the ATP hydrolysis which is coupled to the pumping of protons into a variety of intracellular acid compartments, including the fungal vacuole. We report here the cloning and sequence determination of the gene encoding subunit A from Candida tropicalis. Southern blot hybridization analysis indicates that there is a single gene which encodes this protein. The gene contains a single intron at the extreme 5'-end of the coding region. The gene is predicted to encode a polypeptide of 1088 residues with a calculated molecular mass of 119,019 daltons, yet the mature polypeptide appears to be approximately 67 kDa, indicating that this protein probably undergoes the same sort of processing that is evidenced in the homologous protein from Saccharomyces cerevisiae in which an approximately 50-kDa polypeptide (the spacer) is spliced out of the mature protein. The Candida gene, with and without this middle portion, has been expressed in S. cerevisiae and found to restore a Saccharomyces subunit A deletion mutant (tfp1-delta 8) to apparently wild-type growth at pH 7.6, and normal vacuolar acidification. The peptide sequence of the two predicted mature ends is very similar to the sequences of the analogous proteins from Daucus carota, S. cerevisiae, and Neurospora crassa (60.5, 87.4, and 72.9% identity, respectively), but the middle portion bears only very limited homology with the Saccharomyces protein sequence. Processing of the gene product occurs in S. cerevisiae, Escherichia coli, and in rabbit reticulocyte-mediated in vitro translation, indicating that the excision is probably autocatalytic. The limited sequence identity seen between the Saccharomyces and Candida spacer domains may considerably narrow the functionally important regions responsible for the excision event.