[Pulmonary vein stenosis with pulmonary infarction secondary to primary mediastinal seminoma: a case report]

Pulmonary vein stenosis is a rare condition that is often underdiagnosed and misdiagnosed. The clinical and radiologic manifestations are unspecific such as cough, hemoptysis and pulmonary lesions and are therefore difficult to distinguished with pneumonia and tuberculosis. The present study is a successful case report of pulmonary vein stenosis and pulmonary infraction secondary to mediastinal seminoma. This case suggested that pulmonary vein stenosis should be considered when a mediastinal mass is accompanied by pulmonary opacites that cannot be explained by common causes such as infection.

Cell cycle expression of FLJ25439, a cytokinesis-associated protein, is mediated by D-box recognition and APC/C-Cdc20 regulated degradation

The midbody is a transient structure forming out of the central spindle at late telophase. Both the midbody and central spindle have important functions ensuring completion of cytokinesis and defects in this process may lead to genetic diseases, including cancer. Thus, understanding the mechanisms that control cytokinesis during mitosis can reveal the key components taking part in some of the processes that promote accurate cell division. Our previous study showed that overexpression of FLJ25439 causes cytokinesis defect with midbody arrest and induces tetraploids with prolonged cell growth/cell cycle progression (Pan et al., 2015). Here, we extend our investigation with regard to the expression profile/regulation and cellular localization/function of FLJ25439 during mitosis/cytokinesis. Using a monoclonal antibody 2A4 we found that FLJ25439 expression is cell cycle-dependent and subjected to APC/C complex regulation. Furthermore, it is a novel substrate for the APC/C-Cdc20 complex and its degradation is proteasome-dependent through D-box recognition during mitotic exit. Immunofluorescence microscopy showed it is distributed at the central spindle and midbody, two structures considered important for completion of cell division, in telophase and cytokinesis, respectively, during cell cycle progression. Depletion of FLJ25439 expression revealed defects in chromosome alignment/segregation and delayed mitosis/cytokinesis progression. We thus conclude that FLJ25439 is a hitherto undiscovered factor involved in cytokinesis regulation.

Depletion of UXT, a novel TSG101 interaction protein, leads to enhanced CEP55 attenuation through lysosome degradation

The expression level of CEP55, a centrosome and midbody-associated protein is pivotal for cell cytokinesis and is significantly correlated with tumor stage. Our previous study demonstrated that ectopic expression of TSG101 can decrease androgen receptor expression level through the lysosome degradation pathway. Here, we further extended the investigation of TSG101 in modulating protein levels through lysosomes, and identified ubiquitously expressed transcript (UXT) to be a novel TSG101 interaction partner associated with TSG101-containing cytoplasmic vesicles. We also demonstrated that CEP55 can be recruited to TSG101 cytoplasmic vesicles resulting in downregulation of CEP55 through lysosome degradation. Moreover, UXT depletion promoted TSG101 vesicle-lysosome association and elevated autophagic carrier flux to enhance CEP55 degradation upon TSG101 overexpression. In summary, we identified a novel CEP55 regulation pathway mediated by TSG101 overexpression via lysosome degradation and revealed that UXT plays a role in the late endosome/autophagosome-lysosome fusion event, engaging in TSG101-mediated lysosome degradation.

Abstract B28: Cep55 regulates YAP/TAZ expression and localization during cell cycle progression

Cell cycle regulation plays a pivotal role in controlling cell proliferation and survival. Aberrant expression of cell cycle-associated genes generally afflicts cells with tumor-prone characteristics and promotes chromosome instability. Cep55 (Centrosome Protein 55kDa; also known as c10orf3 and FLJ10540) was identified as an important regulator of cytokinesis involved in cell growth and proliferation. It is associated with central spindle and midbody during cell cycle progression and cooperates with members of endosomal sorting complex required for transport (ESCRT) machinery to constrict intracellular bridge for cell abscission. In addition to cytokinesis, Cep55 is involved in regulating the PI3K/AKT pathway as well as promoting tumorigenesis. In search of novel Cep55 interplayers that may abrogate their expression upon loss of cep55 expression, we set out experiments with cultured cells exogenously expressed Flag-tagged wild type (wt) Cep 55 versus shRNAs against Cep55 and subjected immunoprecipitates to LC-MS/MS. The Hippo pathway components YAP and its paralogue TAZ were found to be diminished apparently in Cep55 null sample compared with wt counterpart. To confirm if Cep55 knockdown affects expression of Hippo pathway, we transfected 293T cells with Cep55 shRNAs and detected expression of Hippo core components with Western blots. Hippo components such as Merlin, Mst, and Lats are without effect in expression level, with the exception of YAP/TAZ whose expression was decreased extensively. Immunofluorescent microscopy reveals YAP/TAZ colocalized with Cep55 at central spindle and midbody during mitosis; however, depletion of Cep55 results in diffusion of YAP/TAZ at midbody, suggesting cep55 is required for midbody localization of YAP/TAZ. In contrast, knockdown of YAP/TAZ did not significantly alter Cep55 localization to the midbody ring but displays phenotype, such as multinuclear cells and micronuclei, similar to that observed in Cep55-depleted cells. Together our data provide evidence that Cep55-YAP/TAZ interaction plays an important role in cytokinesis and may support a biologic interplay between the Hippo-YAP and PI3K-AKT-mTOR pathways.

Note: This abstract was not presented at the conference.

Citation Format: Yen-Ming Lin, Chu-Han Wu, Pin Ouyang. Cep55 regulates YAP/TAZ expression and localization during cell cycle progression [abstract]. In: Proceedings of the AACR Special Conference on the Hippo Pathway: Signaling, Cancer, and Beyond; 2019 May 8-11; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(8_Suppl):Abstract nr B28.

4260Loss of Pnn in cardiomyocytes results in impairment of intercalated discs and arrhythmogenic cardiomyopathy in mice

Background

Pnn, a multiple functional protein that localizes within nucleus and in the cytoplasmic region of desmosome. Although recent studies have characterized the physiological role of nuclear Pnn in regulating pre-mRNA alternative splicing and gene transcription, the function of Pnn in desmosome, particularly in cardiomyocytes, remains unidentified.

Purpose and methods

In the present study, we applied an inducible cardiomyocyte-specific Pnn depletion mouse model (Myh6-CreERT2, Pnnflox/flox) to observe the impact of loss of Pnn on cardiac structure and function in adult mice.

Results

Six weeks after tamoxifen injection to induce cardiac Pnn depletion, the electrocardiographic abnormalities and decrease of left ventricular ejection fraction (LVEF) were observed. Histopathological examination showed that the proliferation of cardiac fibroblasts and expression of α-smooth muscle actin were increased with Pnn depletion, while the cell-cell connection among cardiomyocytes were impaired. In addition, cellular hypertrophy and decrease of capillary density were also found. Results from Immunofluorescent staining further showed that the distribution pattern of desmosomal proteins and adherent junctional proteins, including desmoglein, desmocollin, plakoglobin, plakophllin, desmoplakin and β-catenin were altered in the cardiomyocytes with Pnn depletion. Both desmosomal and adherent junctional proteins were translocated form cell-cell junction to cytoplasm, indicating the disruption of intercalated discs in Pnn-depleted cardiomyocytes. Microarray data also indicated that loss of cardiac Pnn regulated the mRNA expression of genes responsible for extracellular matrix-receptor interaction, ribosome, and integrin. In addition, expression levels of oxidative stress-associated proteins were significantly regulated by Pnn depletion.

Impairment of intercalated disc

Conclusion

Results from present study indicated that Pnn plays an essential role in the maintenance of intercalated disc integrity of cardiomyocytes, while cardiomyocyte-specific loss of Pnn leads to arrhythmogenic cardiomyopathy in mice.

Acknowledgement/Funding

Ministry of Science and Technology Taiwan, MOST-106-2320-B-182A-010-MY3

Ablation of Bax and Bak protects skeletal muscle against pressure-induced injury

Pressure-induced injury (PI), such as a pressure ulcer, in patients with limited mobility is a healthcare issue worldwide. PI is an injury to skin and its underlying tissue such as skeletal muscle. Muscle compression, composed of mechanical deformation of muscle and external load, leads to localized ischemia and subsequent unloading reperfusion and, hence, a pressure ulcer in bed-bound patients. Although the gross factors involved in PI have been identified, little is known about the exact disease mechanism or its links to apoptosis, autophagy and inflammation. Here, we report that PI is mediated by intrinsic apoptosis and exacerbated by autophagy. Conditional ablation of Bax and Bak activates the Akt-mTOR pathway and Bnip3-mediated mitophagy and preserves mitochondrial contents in compressed muscle. Moreover, we find that the presence/absence of Bax and Bak alters the roles and functions of autophagy in PI. Our results suggest that manipulating apoptosis and autophagy are potential therapeutic targets for treatment and prevention of PI.

Bmp5 Regulates Neural Crest Cell Survival and Proliferation via Two Different Signaling Pathways

Neural crest progenitor cells, which give rise to many ectodermal and mesodermal derivatives, must maintain a delicate balance of apoptosis and proliferation for their final tissue contributions. Here we show that zebrafish bmp5 is expressed in neural crest progenitor cells and that it activates the Smad and Erk signaling pathways to regulate cell survival and proliferation, respectively. Loss-of-function analysis showed that Bmp5 was required for cell survival and this response is mediated by the Smad-Msxb signaling cascade. However, the Bmp5-Smad-Msxb signaling pathway had no effect on cell proliferation. In contrast, Bmp5 was sufficient to induce cell proliferation through the Mek-Erk-Id3 signaling cascade, whereas disruption of this signaling cascade had no effect on cell survival. Taken together, our results demonstrate an important regulatory mechanism for bone morphogenic protein-initiated signal transduction underlying the formation of neural crest progenitors. Stem Cells 2017;35:1003-1014.

Diet and adipose tissue distributions: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

Dietary quality affects cardiometabolic risk, yet its pathways of influence on regional adipose tissue depots involved in metabolic and diabetes risk are not well established. We aimed to investigate the relationship between dietary quality and regional adiposity.

METHODS AND RESULTS

We investigated 5079 individuals in the Multi-Ethnic Study of Atherosclerosis (MESA) who had food-frequency questionnaires and measurement of pericardial fat and hepatic attenuation at the baseline study visit in MESA, as well as a subgroup with imaging for visceral and subcutaneous fat (N = 1390). A dietary quality score (DietQuality) was constructed to include established food group constituents of a Mediterranean-type diet. Linear models estimated associations of dietary score as well as its constituents with regional adiposity. Baseline mean age was 61 (± 10) years, and approximately half of the participants (47%) were male. Those with a higher DietQuality score were generally older, female, with a lower body mass index, C-reactive protein, and markers of insulin resistance. After adjustment, a higher DietQuality score was associated with lower visceral fat (lowest vs. highest dietary score quartile: 523.6 vs. 460.5 cm(2)/m; P < 0.01 for trend), pericardial fat (47.5 vs. 41.3 cm(3)/m; P < 0.01 for trend), lesser hepatic steatosis (by hepatic attenuation; 58.6 vs. 60.7 Hounsfield units; P < 0.01 for trend), but not subcutaneous fat (P = 0.39). Greater fruits, vegetables, whole grains, seeds/nuts and yogurt intake were associated with decreased adiposity, while red/processed meats were associated with greater regional adiposity.

CONCLUSION

A higher quality diet pattern is associated with less regional adiposity, suggesting a potential mechanism of beneficial dietary effects on diabetes, metabolic, and cardiovascular risk.

Target disruption of ribosomal protein pNO40 accelerates aging and impairs osteogenic differentiation of mesenchymal stem cells

pNO40/PS1D, a novel nucleolar protein, has been characterized as a core protein of eukaryotic 60S ribosome and at least two splicing forms of pNO40 mRNAs with alternative starting sites have been identified. Through production of knockout (ko) mice with either exon 2 (△E2), exon 4 (△E4) or △E2+E4 targeted disruption we identified a cryptic splicing product occurring in the ko tissues examined which in general cannot be observed in regular RT-PCR detection of wild-type (wt) animals. Among ko animals, △E4 null embryos exhibited prominent senescence-associated β-galactosidase (SA-β-gal) staining, a marker for senescent cells, in notochord, forelimbs and heart while bone marrow-derived mesenchymal stem cells (MSCs) from △E4 null mice developed accelerated aging and osteogenic differentiation defects compared to those from wt and other isoform mutant mice. Examination of the causal relationship between pNO40 deficiency and MSC-accelerated aging revealed △E4 null disruption in MSCs elicits high levels of ROS and elevated expression levels of p16 and Rb but not p53. Further analysis with iTraq identified CYP1B1, a component of the cytochrome p450 system, as a potential molecule mediating ROS generation in pNO40 deficient MSCs. We herein established a mouse model of MSC aging through pNO40-targeted depletion and demonstrated the effects of loss of pNO40 on bone homeostasis.

Abstract LB-082: FLJ25439, a novel cytokinesis-associated protein, induces tetraploidization and maintains chromosomal stability via enhancing expression of endoplasmic reticulum stress chaperones

Purpose of the study: Identify and characterize a novel D box-containing protein, FLJ25439 for tetraploid induction and maintenance of genomic stability.

Pertinent experimental procedures: Immunofluorescent microscopy and flow cytometry for cell cycle determination. Proteomics and bioinformatics approaches for protein category profiling.

Summary of the data: Investigation of the mechanisms leading to aneuploidy and polyploidy is critical to cancer research. Previous studies have provided strong evidence of the importance of tetraploidization as an early step in tumorigenesis. In cancer cells, tetraploid cells may contribute to abnormal mitotic progression, which may be associated with cytokinesis failure. Tetraploidy leads to genomic instability due to centrosome and chromosome over-replication. Until now, the mechanism by which cells maintain tetraploid status has been unknown. Here, we identified a novel D box-containing protein, FLJ25439, which displays a dynamic expression profile during mitosis/cytokinesis with the midbody as the most prominent associated structure. To understand the function of FLJ25439, we established stable cell lines overexpressing FLJ25439. FLJ25439-overexpression cells grew slower and displayed a tetraploid DNA content in comparison with diploid parental cells. They also showed aberrant mitosis and dysregulated expression of p53, pRb and p21, suggesting a defect in cell cycle progression. To explore the molecular mechanisms responsible for FLJ25439-induced tetraploidization, we conducted a comparative analysis of the global protein expression patterns of wild type and overexpressors using proteomics and bioinformatics approaches. Protein category profiling indicated that FLJ25439 is involved in pathways related to anti-apoptosis, protein folding, the cell cycle, and cytoskeleton regulation. Specifically, genotoxic-stress- and ER stress-related chaperone proteins greatly contributed to the FLJ25439 overexpression phenotypes.

Conclusion: The results of this study pave the way to our further understanding of the role of FLJ25439, a novel cytokinesis-related protein in protecting cells from environmental stress and tetraploid formation.

Note: This abstract was not presented at the meeting.

Citation Format: Pin Ouyang. FLJ25439, a novel cytokinesis-associated protein, induces tetraploidization and maintains chromosomal stability via enhancing expression of endoplasmic reticulum stress chaperones. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-082. doi:10.1158/1538-7445.AM2015-LB-082

FLJ25439, a novel cytokinesis-associated protein, induces tetraploidization and maintains chromosomal stability via enhancing expression of endoplasmic reticulum stress chaperones

Investigation of the mechanisms leading to aneuploidy and polyploidy is critical to cancer research. Previous studies have provided strong evidence of the importance of tetraploidization as an early step in tumorigenesis. In cancer cells, tetraploid cells may contribute to abnormal mitotic progression, which may be associated with cytokinesis failure. Tetraploidy leads to genomic instability due to centrosome and chromosome over-replication. Until now, the mechanism by which cells maintain tetraploid status has been unknown. Here, we identified a novel D box-containing protein, FLJ25439, which displays a dynamic expression profile during mitosis/cytokinesis with the midbody as the most prominent associated structure. To understand the function of FLJ25439, we established stable cell lines overexpressing FLJ25439. FLJ25439-overexpression cells grew slower and displayed a tetraploid DNA content in comparison with diploid parental cells. They also showed aberrant mitosis and dysregulated expression of p53, pRb and p21, suggesting a defect in cell cycle progression. To explore the molecular mechanisms responsible for FLJ25439-induced tetraploidization, we conducted a comparative analysis of the global protein expression patterns of wild type and overexpressors using proteomics and bioinformatics approaches. Protein category profiling indicated that FLJ25439 is involved in pathways related to anti-apoptosis, protein folding, the cell cycle, and cytoskeleton regulation. Specifically, genotoxic-stress- and ER stress-related chaperone proteins greatly contributed to the FLJ25439 overexpression phenotypes. The results of this study pave the way to our further understanding of the role of this novel cytokinesis-related protein in protecting cells from environmental stress and tetraploid formation.

Abstract P1-08-11: Association of variants in candidate genes on lipid profiles in women with early breast cancer on adjuvant aromatase inhibitor therapy

Background

Aromatase inhibitors (AI) can exert unfavorable effects on lipid profiles, but previous studies have reported inconsistent results. Given the intricate biological relationship between estrogen and lipid profiles, these mixed results may be explained in part by variation in genes encoding proteins involved in the drug's target and in estrogen metabolism and signaling. The purpose of this study was to investigate associations of single-nucleotide polymorphisms (SNP) in candidate genes with AI-mediated changes in lipid profiles.

Methods

We completed a prospective multicenter randomized observational open-label study to test the association of SNPs in candidate genes on biomarkers of estrogenic and anti-estrogenic activity in post-menopausal women with early breast cancer who were recommended adjuvant AI therapy. Eligible women were randomly assigned to exemestane or letrozole, and were followed for 2 years. We genotyped 137 SNPs from germ line DNA in the following candidate genes: ARVCF, COMT, CYP19A1, ESR1, ESR2, PGR, EP300, EZH2, NCOA1-3, NCOR1-2, NRIP, and PELP1. Lipid profiles including total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides (TG) were measured at baseline and 3 months after initiating AI. We conducted genetic association data analysis and multivariate linear regressions to analyze the genetic effects using dominant, recessive, and additive models. Multivariate analysis included age, body mass index, prior hormone replacement therapy, and prior tamoxifen. To adjust for multiple comparisons, only SNPs with a p&lt;0.0003 were considered significant.

Results

We enrolled 502 women in to the study, but for this analysis we excluded women who did not have genetic data (n = 33), had incomplete data (n = 23), discontinued or crossed over AI therapy (n = 48), women not fasting at both time points (n = 89), or those on lipid-lowering medications (n = 162). A total of 200 women were evaluable (letrozole 107, exemestane 93). Lipid profiles in all patients (n = 200) at baseline and 3 months after initiating AI, respectively, were as follows: TC 204.9 and 203.3 (unchanged, p = 0.43); HDL 61.3 and 56.8 (decreased, p = 6.3E-10); LDL 122.2 and 124.6 (unchanged, p = 0.22); and TG 107.1 and 103.6 (unchanged, p = 0.26). Genetic association and multivariate analysis revealed that SNPs in ESR1 and NCOR1 are significantly associated with additional changes in lipid parameters as summarized in Table 1.

Table 1.Significant findings of multivariate linear regressions analyzing genetic associations between candidate gene SNPs and lipid profiles of AI-treated women.CohortNumberSNP (gene)Minor Allele FrequencyLipid ParameterModel UsedMean Absolute Change (mg/dL)P-valueAll patients184rs9340958 (ESR1)0.07TCRecessive-2.250.0003Letrozole96rs9340958 (ESR1)0.07TCRecessive5.280.00009 101rs3020368 (ESR1)0.09TCRecessive6.350.00007Exemestane93rs3798758 (ESR1)0.03HDLDominant, additive-7.970.00001 88rs926848 (ESR1)0.03HDLDominant, additive-7.970.00002 93rs61753150 (NCOR1)0.01TGDominant, additive-11.630.00003

Conclusions

Variants in genes involved in estrogen metabolism and signaling are associated with changes in lipid profiles in AI-treated women and should be validated in other studies.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-11.

Enhanced cadmium resistance and accumulation in Pseudomonas putida KT2440 expressing the phytochelatin synthase gene of Schizosaccharomyces pombe

Phytochelatins (PCs) are cysteine-rich peptides with high binding affinity for toxic metals. Expressing the PC synthase gene (PCS) in plant growth-promoting bacteria may enhance its metal resistance and accumulation, consequently increasing phytoremediation efficiency in heavy metal pollution. In this study, PCS from Schizosaccharomyces pombe was cloned and expressed in Pseudomonas putida KT2440, which was confirmed by real-time RT-PCR through an increase in SpPCS mRNA expression level when induced by 20 μmol of CdCl2 in the transformed Ps. putida cells. The recombined strain KT2440-SpPCS exhibited enhanced Cd, Ag and Hg resistance. Compared with the original strain, KT2440-SpPCS also displayed a threefold to fivefold increase in Cd accumulation (14·32 μmol g(-1) to 17·38 μmol g(-1) ; dry weight) when grown in 30 and 50 μmol CdCl2 , along with an increase in nonprotein thiols. Further experiments showed significantly enhanced germination rates and growth of wheat seeds in 0·1 mmol to 1·0 mmol Cd when inoculated with KT2440-SpPCS. This study shows potential use of Ps. putida KT2440-SpPCS in plants to construct a symbiotic system for an enhanced phytoremediation of heavy metal-contaminated environments.

SIGNIFICANCE AND IMPACT OF THE STUDY

The symbiotic system of using plant growth-promoting bacteria Pseudomonas putida to express phytochelatin synthase gene of Schizosaccharomyces pombe together in plants resulted in high heavy metal resistance and high accumulation capacity, suggesting potential enhancement in phytoremediation of heavy metal-contaminated environments.

Dissection of the role of Pinin in the development of zebrafish posterior pharyngeal cartilages

Pinin (pnn), a nuclear and desmosome-associated SR-like protein, has been shown to play multiple roles in cell adhesion, transcriptional regulation, pre-mRNA splicing and mRNA export. Because of the embryonic lethality of pnn-deficient mice, here we used the zebrafish system to investigate the functions of pnn. Injection of morpholinos into zebrafish to knockdown pnn resulted in several obvious defective phenotypes, such as short body, bent tail, and an abnormal pigment distribution pattern. Moreover, aberrant blood vessels were formed, and most of the cartilages of pharyngeal arches 3-7 were reduced or absent in pnn morphants. Because most of the defects manifested by pnn morphants were reminiscent of those caused by neural crest-derived malformation, we investigated the effects of pnn deficiency in the development of neural crest cells. Neural crest induction and specification were not hindered in pnn morphants, as revealed by normal expression of early crest gene, sox10. However, the morphants failed to express the pre-chondrogenic gene, sox9a, in cells populating the posterior pharyngeal arches. The reduction of chondrogenic precursors resulted from inhibition of proliferation of neural crest cells, but not from cellular apoptosis or premature differentiation in pnn morphants. These data demonstrate that pnn is essential for the maintenance of subsets of neural crest cells, and that in zebrafish proper cranial neural crest proliferation and differentiation are dependent on pnn expression.

Centrosomal protein 55 (Cep55) stability is negatively regulated by p53 protein through Polo-like kinase 1 (Plk1)

Centrosomal protein 55 (Cep55), which is localized to the centrosome in interphase cells and recruited to the midbody during cytokinesis, is a regulator required for the completion of cell abscission. Up-regulation of Cep55 and inactivation of p53 occur in the majority of human cancers, raising the possibility of a link between these two genes. In this study we evaluated the role of p53 in Cep55 regulation. We demonstrated that Cep55 expression levels are well correlated with cancer cell growth rate and that p53 is able to negatively regulate Cep55 protein and promoter activity. Down-regulation of expression of Cep55 was accompanied by repression of polo-like kinase 1 (Plk1) levels due to p53 induction. Overexpression of Plk1 and knockdown of p53 expression both enhanced the post-translational protein stability of Cep55. BI 2356, a selective Plk1 inhibitor, however, prevented Cep55 accumulation in p53 knockdown cells while persistently keeping Plk1 levels elevated. Our results, therefore, indicate the existence of a p53-Plk1-Cep55 axis in which p53 negatively regulates expression of Cep55, through Plk1 which, in turn, is a positive regulator of Cep55 protein stability.

Loss of Pnn expression results in mouse early embryonic lethality and cellular apoptosis through SRSF1-mediated alternative expression of Bcl-xS and ICA**

Pinin (Pnn), a serine/arginine-rich (SR)-related protein, has been shown to play multiple roles within eukaryotic cells including in cell-cell adhesion, cell migration, regulation of gene transcription, mRNA export, and alternative splicing. In this study, an attempt to generate mice homozygously deficient in Pnn failed due to early embryonic lethality. To evaluate the effects of loss of Pnn expression on cell survival, RNA interference experiments were performed in MCF-7 cells. With Pnn-depletion, cellular apoptosis and nuclear condensation were observed. In addition, nuclear speckles were disrupted, and expression levels of SR proteins were diminished. RT-PCR analysis showed that alternative splicing patterns of SRSF1 as well as of apoptosis-related genes Bcl-x and ICAD were altered and expression levels of Bim isoforms were modulated in Pnn-depleted cells. Cellular apoptosis induced by Pnn depletion was rescued by overexpression of SRSF1 which also restored generation of Bcl-xL and functionless ICAD. Pnn expression is, therefore, essential for survival of mouse embryos and the breast carcinoma cell line MCF-7. Moreover, Pnn-depletion, modulated by SRSF1, determines cellular apoptosis through activation of expression of pro-apoptotic Bcl-xS transcripts.

Association of endothelial and oxidative stress with metabolic syndrome and subclinical atherosclerosis: multi-ethnic study of atherosclerosis

Objectives

A cluster of metabolic abnormalities termed metabolic syndrome (MetS) is associated with vascular endothelial dysfunction and oxidative internal milieu. We examined whether the association of MetS with subclinical atherosclerosis is explained by biomarkers of endothelial damage and oxidative stress.

Methods

MESA is a population based study of 45-84 year old individuals of four US ethnicities without clinical cardiovascular disease. A random sample of 997 MESA participants had data on the following biomarkers: von Willebrand Factor, soluble intercellular adhesion molecule-1 (sICAM1), CD40 ligand, soluble thrombomodulin, E-selectin, and oxidized LDL (oxLDL). We examined whether the associations of MetS with B-mode ultrasound-defined common and internal carotid intimal medial thickness (IMT) and coronary artery calcium (CAC) measured using computerized tomography were explained by the biomarkers using multiple regression methods.

Results

MetS was associated with higher levels of each of the biomarkers (p<0.001, CD40L suggestive association p=0.004), with greater IMT (p<0.001), and with greater extent of CAC in those in whom CAC was detectable (p=0.01). The association of MetS with measures of subclinical atherosclerosis remained unchanged after adjustment for the biomarkers. After adjusting for MetS, oxLDL was suggestively associated with greater prevalence of detectable CAC (p=0.005) and thicker internal carotid IMT (p=0.002), while sICAM-1was significantly associated with greater prevalence of detectable CAC (p=0.001).

Conclusions

The association of MetS with subclinical atherosclerosis was independent of its association with biomarkers of endothelial damage and oxidative stress, suggesting that metabolic abnormalities and oxidative endothelial damage may lead to atherosclerotic disease through distinct mechanisms.

Characterization of centrosomal proteins Cep55 and pericentrin in intercellular bridges of mouse testes

Centrosomal protein 55 (Cep55), located in the centrosome in interphase cells and recruited to the midbody during cytokinesis, is essential for completion of cell abscission. Northern blot previously showed that a high level of Cep55 is predominantly expressed in the testis. In the present study, we examined the spatial and temporal expression patterns of Cep55 during mouse testis maturation. We found that Cep55, together with pericentrin, another centrosomal protein, were localized to the intercellular bridges (IBs) interconnecting spermatogenic cells in a syncytium. The IBs were elaborated as a double ring structure formed by an inner ring decorated by Cep55 or pericentrin and an outer ring of mitotic kinesin-like protein 1 (MKLP1) in the male germ cell in early postnatal stages and adulthood. In addition, Cep55 and pericentrin were also localized to the acrosome region and flagellum neck and middle piece in elongated spermatids, respectively. These results suggest that Cep55 and pericentrin are required for the stable bridge between germ cells during spermatogenesis and spermiogenesis.

Chitosan production from hemicellulose hydrolysate of corn straw: impact of degradation products on Rhizopus oryzae growth and chitosan fermentation

AIMS

To examine the potential use of hemicellulose hydrolysate (HH) for the production of chitosan by Rhizopus oryzae and investigate the influence of contents in HH on mycelia growth and chitosan synthesis.

METHODS AND RESULTS

Compared to xylose medium, HH enhanced mycelia growth, chitosan content and production of R. oryzae by 10.2, 64.5 and 82.1%, respectively. During sulfuric acid hydrolysis of corn straw, sugars (glucose, galactose, etc) and inhibitors (formic acid, acetic acid and furfural) were generated. Acetic acid (2.14 g l(-1)) and formic acid (0.83 g l(-1)) were stimulative, while furfural (0.55 g l(-1)) was inhibitory. Inhibitors, at different concentrations, increased the mycelia growth and chitosan production by 24.5-37.8 and 60.1-207.1%.

CONCLUSIONS

HH of corn straw is a good source for chitosan production. Inhibitors in HH, at proper concentrations, can enhance chitosan production greatly.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work for the first time reported chitosan production from HH. Chitosan production can be greatly enhanced by cheap chemicals such as inhibitors in HH.

Polyglutamine-expanded ataxin-3 causes cerebellar dysfunction of SCA3 transgenic mice by inducing transcriptional dysregulation

In the present study, we prepared a SCA3 animal model by generating transgenic mice expressing polyglutamine-expanded ataxin-3-Q79. Ataxin-3-Q79 was expressed in brain areas implicated in SCA3 neurodegeneration, including cerebellum, pontine nucleus and substantia nigra. Ataxin-3-Q79 transgenic mice displayed motor dysfunction with an onset age of 5-6 months, and neurological symptoms deteriorated in the following months. A prominent neuronal loss was not found in the cerebellum of 10 to 11-month-old ataxin-3-Q79 mice displaying pronounced ataxic symptoms, suggesting that instead of neuronal demise, ataxin-3-Q79 causes neuronal dysfunction of the cerebellum and resulting ataxia. To test the involvement of transcriptional dysregulation in ataxin-3-Q79-induced cerebellar malfunction, microarray analysis and real-time RT-PCR assays were performed to identify altered cerebellar mRNA expressions of ataxin-3-Q79 mice. Compared to non-transgenic mice or mice expressing wild-type ataxin-3-Q22, 10 to 11-month-old ataxin-3-Q79 mice exhibited downregulated mRNA expressions of proteins involved in glutamatergic neurotransmission, intracellular calcium signaling/mobilization or MAP kinase pathways, GABA(A/B) receptor subunits, heat shock proteins and transcription factor regulating neuronal survival and differentiation. Upregulated expressions of Bax, cyclin D1 and CDK5-p39, which may mediate neuronal death, were also observed in ataxin-3-Q79 transgenic mice. The involvement of transcriptional abnormality in initiating the pathological process of SCA3 was indicated by the finding that 4 to 5-month-old ataxin-3-Q79 mice, which did not display neurological phenotype, exhibited downregulated mRNA levels of genes involved in glutamatergic signaling and signal transduction. Our study suggests that polyglutamine-expanded ataxin-3 causes cerebellar dysfunction and ataxia by disrupting the normal pattern of gene transcriptions.

Plasma hemostatic factors and endothelial markers in four racial/ethnic groups: the MESA study

BACKGROUND

Hemostatic factors and endothelial markers may play some role in racial/ethnic differences in cardiovascular disease (CVD) rates. However, little information exists on hemostatic factors and endothelial markers across racial/ethnic groups.

OBJECTIVES

To describe, in four American racial/ethnic groups (Caucasian, Black, Hispanic, and Chinese), mean levels of selected hemostatic factors and endothelial markers.

PATIENTS AND METHODS

Multi-ethnic Study of Atherosclerosis baseline data were used (participant age: 45-84 years). Sex-specific analysis of covariance models, and t-tests for pairwise comparisons, were used to compare means of factors and markers. Adjustments were made for demographics and traditional CVD risk factors. Differences were significant at P < 0.05.

RESULTS

Blacks had the highest levels of factor VIII, D-Dimer, plasmin-antiplasmin (PAP), and von Willebrand factor, among the highest levels of fibrinogen and E-selectin (women only), but among the lowest levels of intercellular adhesion molecule 1 (ICAM-1), and, in men, the lowest levels of plasminogen activator inhibitor-1 (PAI-1). Whites and Hispanics tended to have intermediate levels of factors and markers, although they had the highest levels of ICAM-1, and Hispanics had the highest mean levels of fibrinogen and E-selectin (women only). Chinese participants had among the highest levels of PAI-1, but the lowest, or among the lowest, of all other factors and markers. No soluble thrombomodulin differences were observed.

CONCLUSIONS

In this large cohort, hemostatic factor and endothelial marker mean levels varied by race/ethnicity, even after adjustment for traditional CVD risk factors.

Spatial and temporal expression profile of pinin during mouse development

SR and SR-related proteins are splicing regulators involved in embryo development in higher eukaryotes. Pinin (pnn) is a SR-related protein localized both within nucleus (nuclear pnn, N-pnn) and at desmosome of cell-cell adhesion (desmosomal pnn, D-pnn). To investigate the role of N-pnn during mouse embryo development, we examined its expression using Northern blot, real-time RT-PCR, immunostaining, and mRNA in situ hybridization (ISH). On Northern analysis, we found that pnn transcripts display two isoforms due to differential utilization of a polyadenylation site and exhibit tissue variable expression with thymus expressing the highest level of transcript. Analysis of pnn expression in mouse embryos revealed N-pnn expression starts from the two-cell fertilized egg stage and is ubiquitous at all stages of mouse embryo development. ISH and immunofluorescent staining of embryo cryosections showed that during mouse organogenesis N-pnn is highly expressed in the central nervous system. In addition, N-pnn was found to be highly expressed in the cortex region of thymus of E16.5 mouse fetus, while in the hepatic primordium the strongest signals were noted at E13.5 to E14.5 rather than at later developmental stages. Finally, we also determined the subcellular location of N-pnn in photoreceptors of developing retinas by nuclear fractionation and Western blot, because N-pnn displayed a staining pattern reminiscent of cytoplasmic proteins at the microscopic level in developing mouse photoreceptors. Altogether these data provide us with a better understanding of the tissue distribution pattern of N-pnn during mouse development.

Loss of Pnn expression attenuates expression levels of SR family splicing factors and modulates alternative pre-mRNA splicing in vivo

SR and SR-related proteins have been implicated as trans-acting factors that play an important role in splice selection and are involved at specific stages of spliceosome formation. A well-established property of SR protein splicing factors is their ability to influence selection of alternative splice sites in a concentration-dependent manner. Identification of molecules that regulate SR family protein expression is therefore of vital importance in RNA biology. Here we report that depletion of Pnn expression, a SR-related protein with functions involved in pre-mRNA splicing and mRNA export, induces reduced expression of a subset of cellular proteins, especially that of SR family proteins, including SC35, SRm300, SRp55, and SRp40, but not that of other nuclear proteins, such as p53, Mdm2, and ki67. Knocking down Pnn expression was achieved in vitro by siRNA transfection. Expression levels of SR and SR-related proteins in Pnn-depleted cells as compared to those in control cells were evaluated by immunofluorescent staining and Western blot with specific antibodies. In addition, we also demonstrate that loss of Pnn expression could modulate splice site selection of model reporter gene in vivo. Our finding is significant in terms of regulation of SR protein cellular concentration because it reveals that Pnn may play a general role in the control of the cellular amount of family SR proteins through down-regulation of its own expression, thereby providing us with a better understanding of the cellular mechanism by which Pnn fulfills its biological function.

Exercise effects on cardiac size and left ventricular diastolic function: relationships to changes in fitness, fatness, blood pressure and insulin resistance

OBJECTIVES

To determine exercise training effects on cardiac size and left ventricular (LV) diastolic function and relationships of exercise induced changes in physiological and body composition parameters with cardiac parameters.

DESIGN

Prospective, randomised controlled trial.

SUBJECTS

Men and women (63.6 (5.7) years, body mass index 29.5 (4.4) kg/m(2)) with untreated hypertension (systolic blood pressure (BP) 130-159 or diastolic BP 85-99 mm Hg).

MAIN OUTCOME MEASURES

Cardiac size and LV diastolic function, peak oxygen uptake (Vo(2)), muscle strength, general and abdominal fatness, and insulin resistance.

INTERVENTIONS

6 months of exercise training versus usual care.

RESULTS

When analysed by group at six months, cardiac size and LV diastolic function did not differ between exercisers (n = 51) and controls (n = 53), whereas exercisers had significantly higher peak Vo(2) (28 v 24 ml/kg/min) and strength (383 v 329 kg), and lower fatness (34% v 37%), diastolic BP (73 v 75 mm Hg) and insulin resistance (quantitative insulin sensitivity check index 0.35 v 0.34) versus controls (all p <or= 0.05). By regression analysis, among six month changes, increased peak Vo(2) and reduced abdominal fat were associated with increased cardiac size. Increased peak Vo(2) and reduced abdominal fat, BP and insulin resistance were associated with improved LV diastolic function. r Values ranged from 0.20 to 0.32 (p <or= 0.05).

CONCLUSIONS

When examined by group assignment, exercise had no effect on cardiac size or LV diastolic function. When individual variations in six month changes were examined, participants attaining the greatest increases in fitness and reductions in abdominal fatness, insulin resistance and BP showed a modest trend towards physiological hypertrophy characterised by increased cardiac size and improved LV diastolic function. These results suggest that decreased abdominal fatness may have a role in improving cardiovascular health.

Over-expression of SR-cyclophilin, an interaction partner of nuclear pinin, releases SR family splicing factors from nuclear speckles

Pre-mRNA splicing takes place within a dynamic ribonucleoprotein particle called the spliceosome and occurs in an ordered pathway. Although it is known that spliceosome consists of five small nuclear RNAs and at least 50 proteins, little is known about how the interaction among the proteins changes during splicing. Here we identify that SR-cyp, a Moca family of nuclear cyclophilin, interacts and colocalizes with nuclear pinin (pnn), a SR-related protein involving in pre-mRNA splicing. Nuclear pnn interacts with SR-cyp via its C-terminal RS domain. Upon SR-cyp over-expression, however, the subnuclear distribution of nuclear pnn is altered, resulting in its redistribution from nuclear speckles to a diffuse nucleoplasmic form. The diffuse subnuclear distribution of nuclear pnn is not due to epitope masking, accelerated protein turnover or post-translational modification. Furthermore, we find that SR-cyp regulates the subnuclear distribution of other SR family proteins, including SC35 and SRm300, in a similar manner as it does on nuclear pnn. This result is significant because it suggests that SR-cyp plays a general role in modulating the distribution pattern of SR-like and SR proteins, similar to that of Clk (cdc2-like kinase)/STY on SR family splicing factors. SR-cyp might direct its effect via either alteration of protein folding/conformation or of protein-protein interaction and thus may add another control level of regulation of SR family proteins and modification of their functions.

Nuclear Pnn/DRS protein binds to spliced mRNPs and participates in mRNA processing and export via interaction with RNPS1

Pnn/DRS protein is associated with desmosomes and colocalizes with splicing factors in nuclear speckled domains. The potential interaction of Pnn with RNPS1, a pre-mRNA splicing factor and a component of the exon-exon junction complex, prompted us to examine whether Pnn is involved in nuclear mRNA processing. By immunoprecipitation, we found that Pnn associates preferentially with mRNAs produced by splicing in vitro. Oligonucleotide-directed RNase H digestion revealed that Pnn binds to the spliced mRNAs at a position immediately upstream of the splice junction and that 5' splice site utilization determines the location of Pnn in alternatively spliced mRNAs. Immunoprecipitation further showed that Pnn binds to mRNAs produced from a transiently expressed reporter in vivo. Although associated with mRNPs, Pnn is a nuclear-restricted protein as revealed by the heterokaryon assay. Overexpression of an amino-terminal fragment of Pnn that directly interacts with RNPS1 leads to blockage of pre-mRNA splicing. However, although suppression of Pnn expression shows no significant effect on splicing, it leads to some extent to nuclear accumulation of bulk poly(A)(+) RNA. Therefore, Pnn may participate, via its interaction with RNPS1, in mRNA metabolism in the nucleus, including mRNA splicing and export.

Molecular characterization of a novel nucleolar protein, pNO40

We report the discovery and characterization of a novel nucleolar protein. This protein, referred to as pNO40 based on its molecular weight on SDS-PAGE, was identified through yeast two hybrid interaction screen of a human kidney cDNA library using pinin (pnn) protein as the bait. The deduced amino acids of pNO40 derived from cDNA cloning of diverse species display high conservation; 95% identify between human and mouse and 57.3% identity for human and zebrafish. Several distinct domains are discernable in the ORF of pNO40, including a ribosomal protein S1 RNA binding region, a CCHC type zinc finger, and clusters of basic amino acid representing potential nucleolar targeting signal. Immunostaining of endogenous or transfected pNO40 indicated that it is localized to nucleoli of diverse cultured cells, with some concentration in the granular component of nucleoli. Northern blot analysis demonstrated that pNO40 message is expressed ubiquitously across all tissues examined. Characterization of human and mouse pNO40 gene revealed that mouse gene spans 44 kb in length and contains 8 exons, while that of human is 68 kb in length and displays two isoforms generated by alternative splicing of the 5(')-untranslated region and differential usage of translation start site. Based on sequence features and its subcellular location, we predict that pNO40 is a novel nucleolar protein with function related to ribosome maturation and/or biogenesis.

Exercise blood pressure response is related to left ventricular mass

An exaggerated SBP response to exercise has been associated with increased left ventricular (LV) mass in some but not all studies. A total of 43 women and 34 men, aged 55-75 years, without evidence of cardiovascular disease, with a mean resting BP of 142+/-9/77+/-8 mmHg had their BP measured at rest and during maximal treadmill exercise. LV mass was measured using magnetic resonance imaging. LV mass was adjusted for lean body mass, which was assessed by dual energy X-ray absorptiometry. LV mass was within the normal range for the majority of the subjects. Among the resting and exercise BP indices, maximal SBP was the strongest correlate of LV mass (r=0.41, P<0.05). In multivariate analysis, maximal SBP was independently associated with LV mass after adjustment for lean body mass and gender, explaining 3% of the variance (P<0.05). Maximal exercise SBP is a modest but still independent predictor of LV mass in older persons with normal LV mass. These results raise the possibility that the SBP response to maximal exercise is an early marker of LV hypertrophy.

Fitness, fatness and activity as predictors of bone mineral density in older persons

OBJECTIVES

To determine relationships of bone mineral density (BMD) with fitness, physical activity, and body composition and fat distribution.

DESIGN

Cross-sectional.

SETTING

General Clinical Research Center, Johns Hopkins Bayview Medical Center, Baltimore, Maryland.

SUBJECTS

Men (n = 38) and women (n = 46), aged 55-75 years with high normal blood pressure or mild hypertension but otherwise healthy.

METHODS

Aerobic fitness (oxygen uptake) on a treadmill, muscle strength by one-repetition maximum, activity by questionnaire, abdominal obesity by magnetic resonance imaging; anthropometrics, and body composition by dual energy X-ray absorptiometry (DXA) which measured total fat and lean mass, and BMD for the total skeleton, lumbar spine (L1-L4) and total hip.

RESULTS

Aerobic fitness did not correlate with BMD. Using multivariate analysis to ascertain independent contributions to the variance in BMD, in women, with adjustment for hormone replacement therapy (HRT), total skeleton BMD was independently related to muscle strength and abdominal total fat; total hip BMD to body weight; lumbar spine BMD to abdominal total fat. HRT also influenced BMD in the lumbar spine. In men, lumbar spine BMD was independently related to abdominal total fat physical activity and total hip BMD related to lower body strength. P < 0.05 for all of these correlations.

CONCLUSIONS

Abdominal obesity and muscle strength emerge as predominant correlates of BMD in older persons with stronger relationships seen in women. Body weight and HRT also explained portions of the variance in BMD in women. Whether abdominal obesity is simply a marker for general obesity or has independent protective effects on bone is yet to be determined.

Modulation of alternative pre-mRNA splicing in vivo by pinin

Pre-mRNA splicing occurs in a large macromolecular RNA-protein complex called the spliceosome. The major components of the spliceosome include snRNP and SR proteins. We have previously identified an SR-like protein, pinin (pnn), which is localized not only in nuclear speckles but also at desmosomes. The nuclear localization of pnn is a dynamic process because pnn can be found not only with SR proteins in nuclear speckles but also in enlarged speckles following treatment of cells with RNA polymerase II inhibitors, DRB, and alpha-amanitin. Using adenovirus E1A and chimeric calcitonin/dhfr construct as a splicing reporter minigene in combination with cellular cotransfection, we found that pnn regulates alternative 5(') and 3(') splicing by decreasing the use of distal splice sites. Regulation of 5(') splice site choice was also observed for RNPS1, a general splicing activator that interacts with pnn in nuclear speckles. The regulatory ability of pnn in alternative 5(') splicing, however, was not dependent on RNPS1 and a pnn mutant, lacking the N-terminal 167 amino acids, behaved like a dominant negative species, inhibiting E1A splicing when applied in splicing assays. These results provide direct evidence that pnn functions as a splicing regulator which participates itself directly in splicing reaction or indirectly via other components of splicing machinery.

The relationship between vascular wall shear stress and flow-mediated dilation: endothelial function assessed by phase-contrast magnetic resonance angiography

OBJECTIVES

We sought: 1) to investigate the relationship between vascular wall shear stress and flow-mediated dilation (FMD) in humans, and 2) to investigate whether this relationship could explain why FMD is greater in small arteries.

BACKGROUND

Arterial wall shear stress (WSS) is considered to be the primary stimulus for the endothelial-dependent FMD response. However, the relationship between WSS and FMD has not been investigated in humans. Furthermore, FMD is greater in small arteries, though the reasons for this phenomenon are unclear.

METHODS

Using phase-contrast magnetic resonance angiography (PMRCA), we measured hyperemic WSS and FMD in 18 healthy volunteers. Peak systolic WSS was calculated assuming a blunted parabolic velocity profile. Diameter by PCMRA and by ultrasound was compared in nine subjects.

RESULTS

Flow-mediated dilation was linearly proportional to hyperemic peak systolic WSS (r = 0.79, p = 0.0001). Flow-mediated dilation was inversely related to baseline diameter (r = 0.62, p = 0.006), but the hyperemic peak WSS stimulus was also inversely related to baseline diameter (r = 0.47, p = 0.049). Phase-contrast magnetic resonance angiography and ultrasound diameters were compared in nine subjects and correlated well (r = 0.84, p < 0.0001), but diameter by PCMRA was greater (4.1 +/- 0.7 mm vs. 3.7 +/- 0.5 mm, p = 0.009).

CONCLUSION

Arterial FMD is linearly proportional to peak hyperemic WSS in normal subjects. Thus, the endothelial response is linearly proportional to the stimulus. Furthermore, the greater FMD response in small arteries is accounted for, at least partially, by a greater hyperemic WSS stimulus in small arteries. By allowing the calculation of vascular WSS, which is the stimulus for FMD, and by imaging a fixed arterial cross-section, thus reducing operator dependence, PCMRA enhances the assessment of vascular endothelial function.

A model of interfacial inactivation for papain in aqueous organic biphasic systems

A model was proposed to describe the effects of the main factors in aqueous-organic two-liquid-phase media on the stability of papain. The relationships between the half-life of papain activity and these factors including interfacial tension, stirring rate, phase volume ratio and temperature were investigated. The results showed that these factors had notable effects on papain stability except temperature. The correlation coefficient between the model and the experimental data were 0.829, which indicated the model is practicable.

ChoICE PT wire for recanalization of chronically occluded coronary arteries: multiple wires in one?

Percutaneous transluminal coronary angioplasty (PTCA) of chronic total occlusions may be technically difficult and the success rate is limited despite increasing operator experience and improvements in PTCA hardware. The number of guidewires required to cross totally occluded lesions is higher than that for stenotic lesions. The ChoICE polymer-tip (PT) wire (Boston Scientific/Scimed, Inc., Maple Grove, Minnesota) is a relatively new stainless-steel core wire with a hydrophilic-coated polyurethane tip. Though never described in the literature, we found that the distal 4 cm of the wire can be cut and reshaped according to the operator's needs. Thus, instead of reshaping a kinked tip or using another new wire, the former being time-consuming and the latter expensive, one can simply cut off the kinked tip and start again with a "new wire." As the tip is resected, the wire becomes progressively more "intermediate-like" and "standard-like." We report our experience with the ChoICE PT wire in 50 consecutive cases of chronic total occlusions. The cumulative crossing success rates were 13/50 (26%) before any resections, 24/50 (48%) after 1 resection, 41/50 (82%) after 2 resections and 42/50 (84%) after 3 resections. There were no perforations, deaths, myocardial infarctions or need for bypass surgery. Our findings suggest that successful recanalization of chronic total occlusions can be achieved with a high success rate using the ChoICE PT wire. A strategy of progressively resecting the more floppy and kinked distal end can provide multiple uses from a single wire, optimizing recanalization success and obviating the need for additional wires.

Awareness, perception, and knowledge of heart disease risk and prevention among women in the United States. American Heart Association Women's Heart Disease and Stroke Campaign Task Force

CONTEXT

One of 2 women in the United States dies of heart disease or stroke, yet women are underdiagnosed and undertreated for these diseases and their risk factors. Informed decisions to prevent heart disease and stroke depend on awareness of risk factors and knowledge of behaviors to prevent or detect these diseases.

OBJECTIVE

Assess (1) knowledge of risks of heart disease and stroke and (2) perceptions of heart disease and its prevention among women in the United States.

DESIGN AND SETTING

Telephone survey conducted in 1997 of US households, including an oversample of African American and Hispanic women.

PARTICIPANTS

One thousand respondents 25 years or older; 65.8% white, 13.0% African American, and 12.6% Hispanic.

MAIN OUTCOME MEASURES

Knowledge of heart disease and stroke risks, perceptions of heart disease, and knowledge of symptoms and preventive measures.

RESULTS

Only 8% of the respondents identified heart disease and stroke as their greatest health concerns; less than 33% identified heart disease as the leading cause of death. More women aged 25 to 44 years identified breast cancer as the leading cause of death than women 65 years or older. Women aged 25 to 44 years indicated they were not well informed about heart disease and stroke. Although 90% of the women reported that they would like to discuss heart disease or risk reduction with their physicians, more than 70% reported that they had not.

CONCLUSIONS

Most women do not perceive that heart disease is a substantial health concern and report that they are not well informed about their risk. Age influenced knowledge to a greater extent than ethnicity. Programs directed at young women that address the effects of lifestyle behaviors on long-term health are needed. Better communication between physicians and patients is also warranted.

Characterization of the gene encoding pinin/DRS/memA and evidence for its potential tumor suppressor function

Several cell adhesion-related proteins have been shown to act as tumor-suppressors (TS) in the neoplastic progression of epithelial-derived tumors. Pinin/DRS/memA was first identified in our laboratory and it was shown to be a cell adhesion-related molecule. Our previous study demonstrated that restoration of pinin expression in transformed cells not only positively influenced cellular adhesive properties but also reversed the transformed phenotype to more epithelial-like. Here, we show by FISH analysis that the gene locus for pinin is within 14q13. The alignment of the pinin gene with STS markers localized the gene to the previously identified TS locus D14S75-D14S288. Northern analyses revealed diminished pinin mRNA in renal cell carcinomas (RCC) and certain cancer cell lines. Immunohistochemical examination of tumor samples demonstrated absent or greatly reduced pinin in transitional cell carcinoma (TCC) and RCC tumors. TCC-derived J82 cells as well as EcR-293 cells transfected with full-length pinin cDNA demonstrated inhibition of anchorage-independent growth of cells in soft agar. Furthermore, methylation analyses revealed that aberrant methylation of pinin CpG islands was correlated with decreased/absent pinin expression in a subset of tumor tissues. These data lend significant support to the hypothesis that pinin/DRS/memA may act as a tumor suppressor in certain types of cancers.

Antibodies differentiate desmosome-form and nucleus-form pinin: evidence that pinin is a moonlighting protein with dual location at the desmosome and within the nucleus

Pinin is a desmosome-associated protein occurring in epithelia, cardiac muscle, and meninges. This molecule was found to be capable of enhancing cell junction formation and thought to play a key role in reorganization and stabilization of the desmosome-intermediate filament complex in epithelial cells (J. Cell Biol. (1996) 135, 1027-1042). Recently a protein, claimed to be localized exclusively in the nucleus, however, with amino acid sequence identical to pinin, was reported (E. J. Cell Biol. (1998) 75, 295-298). Here I present evidence that pinin exists simultaneously at the desmosome and within the nucleus by generating location-specific monoclonal antibodies. Although the desmosome-form (d-form) and the nucleus-form (n-form) pinin share identical amino acid sequences as demonstrated by cDNA library screening and DNA sequencing, they exhibit remarkably different biochemical properties, reflecting the apparent different multiprotein nature of their differential cellular locations. In addition, the d-form pinin is characterized by a dynamic transport process which involves the gradual diminishing of nuclear materials relative to enhanced anchoring of pinin to the desmosome upon mature cells. Finally I demonstrate that pinin exists in two forms of different gene product: pinin1 and pinin2. These data argue strongly against the statement that pinin is an exclusive nuclear protein and support the notion that pinin is a moonlighting protein with more than one function as a consequence of its dual cellular location.

Methylation of the estrogen receptor gene is associated with aging and atherosclerosis in the cardiovascular system

OBJECTIVE

Methylation of the promoter region of the estrogen receptor gene alpha (ER alpha) occurs as a function of age in human colon, and results in inactivation of gene transcription. In this study, we sought to determine whether such age-related methylation occurs in the cardiovascular system, and whether it is associated with atherosclerotic disease.

METHODS

We used Southern blot analysis to determine the methylation state of the ER alpha gene in human right atrium, aorta, internal mammary artery, saphenous vein, coronary atherectomy samples, as well as cultured aortic endothelial cells and smooth muscle cells.

RESULTS

An age related increase in ER alpha gene methylation occurs in the right atrium (range 6 to 19%, R = 0.36, P < 0.05). Significant levels of ER alpha methylation were detected in both veins and arteries. In addition, ER alpha gene methylation appears to be increased in coronary atherosclerotic plaques when compared to normal proximal aorta (10 +/- 2% versus 4 +/- 1%, P < 0.01). In endothelial cells explanted from human aorta and grown in vitro, ER alpha gene methylation remains low. In contrast, cultured aortic smooth muscle cells contain a high level of ER alpha gene methylation (19-99%).

CONCLUSIONS

Methylation associated inactivation of the ER alpha gene in vascular tissue may play a role in atherogenesis and aging of the vascular system. This potentially reversible defect may provide a new target for intervention in heart disease.

[Studies on preparation of L-phenylalanine from phenylpyruvic acid by E. coli EP8-10]

E. coli EP8-10 was selected from the soil. It was able to produce the transaminase with high activity when it was cultivated on the medium containing peptone and beef extract. Optimum conditions of enzyme reaction was: phenylpyruvic acid's concentration of 0.3-0.5 mol/L, L-Asptaric acid used as amino donor, pH 8.5 37 degrees C. When phenylpyruvic acid was 0.3 mol/L, 48 g/L L-phenylalanine was produced after 6 h with 97% conversion rate.