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61.
Emily Banks Grace Joshy Walter P. Abhayaratna Leonard Kritharides Peter S. Macdonald Rosemary J. Korda John P. Chalmers 《PLoS medicine》2013,10(1)
Background
Erectile dysfunction is an emerging risk marker for future cardiovascular disease (CVD) events; however, evidence on dose response and specific CVD outcomes is limited. This study investigates the relationship between severity of erectile dysfunction and specific CVD outcomes.Methods and Findings
We conducted a prospective population-based Australian study (the 45 and Up Study) linking questionnaire data from 2006–2009 with hospitalisation and death data to 30 June and 31 Dec 2010 respectively for 95,038 men aged ≥45 y. Cox proportional hazards models were used to examine the relationship of reported severity of erectile dysfunction to all-cause mortality and first CVD-related hospitalisation since baseline in men with and without previous CVD, adjusting for age, smoking, alcohol consumption, marital status, income, education, physical activity, body mass index, diabetes, and hypertension and/or hypercholesterolaemia treatment. There were 7,855 incident admissions for CVD and 2,304 deaths during follow-up (mean time from recruitment, 2.2 y for CVD admission and 2.8 y for mortality). Risks of CVD and death increased steadily with severity of erectile dysfunction. Among men without previous CVD, those with severe versus no erectile dysfunction had significantly increased risks of ischaemic heart disease (adjusted relative risk [RR] = 1.60, 95% CI 1.31–1.95), heart failure (8.00, 2.64–24.2), peripheral vascular disease (1.92, 1.12–3.29), “other” CVD (1.26, 1.05–1.51), all CVD combined (1.35, 1.19–1.53), and all-cause mortality (1.93, 1.52–2.44). For men with previous CVD, corresponding RRs (95% CI) were 1.70 (1.46–1.98), 4.40 (2.64–7.33), 2.46 (1.63–3.70), 1.40 (1.21–1.63), 1.64 (1.48–1.81), and 2.37 (1.87–3.01), respectively. Among men without previous CVD, RRs of more specific CVDs increased significantly with severe versus no erectile dysfunction, including acute myocardial infarction (1.66, 1.22–2.26), atrioventricular and left bundle branch block (6.62, 1.86–23.56), and (peripheral) atherosclerosis (2.47, 1.18–5.15), with no significant difference in risk for conditions such as primary hypertension (0.61, 0.16–2.35) and intracerebral haemorrhage (0.78, 0.20–2.97).Conclusions
These findings give support for CVD risk assessment in men with erectile dysfunction who have not already undergone assessment. The utility of erectile dysfunction as a clinical risk prediction tool requires specific testing. Please see later in the article for the Editors'' Summary 相似文献62.
Jason S. Long Wendy A. Howard Alejandro Nú?ez Olivier Moncorgé Samantha Lycett Jill Banks Wendy S. Barclay 《Journal of virology》2013,87(18):9983-9996
Clade 2.2 Eurasian-lineage H5N1 highly pathogenic avian influenza viruses (HPAIVs) were first detected in Qinghai Lake, China, in 2005 and subsequently spread through Asia, Europe, and Africa. Importantly, these viruses carried a lysine at amino acid position 627 of the PB2 protein (PB2 627K), a known mammalian adaptation motif. Previous avian influenza virus isolates have carried glutamic acid in this position (PB2 627E), commonly described to restrict virus polymerase function in the mammalian host. We sought to examine the effect of PB2 627K on viral maintenance in the avian reservoir. Viruses constructed by reverse genetics were engineered to contain converse PB2 627K/E mutations in a Eurasian H5N1 virus (A/turkey/Turkey/5/2005 [Ty/05]) and, for comparison, a historical pre-Asian H5N1 HPAIV that naturally bears PB2 627E (A/turkey/England/50-92/1991 [50-92]). The 50-92 PB2 627K was genetically unstable during virus propagation, resulting in reversion to PB2 627E or the accumulation of the additional mutation PB2 628R and/or a synonymous mutation from an A to a G nucleotide at nucleotide position 1869 (PB2 A1869G). Intriguingly, PB2 628R and/or A1869G appeared to improve the genetic stability of 50-92 PB2 627K. However, the replication of 50-92 PB2 627K in conjunction with these stabilizing mutations was significantly restricted in experimentally infected chickens, where reversion to PB2 627E occurred. In contrast, no significant effects on viral fitness were observed for Ty/05 PB2 627E or 627K in in vitro or in vivo experiments. Our observations suggest that PB2 627K is supported in Eurasian-lineage viruses; in contrast, PB2 627K carries a significant fitness cost in the historical pre-Asian 50-92 virus. 相似文献
63.
M. J. Cohen A. F. Yousef P. Massimi G. J. Fonseca B. Todorovic P. Pelka A. S. Turnell L. Banks J. S. Mymryk 《Journal of virology》2013,87(18):10348-10355
Human adenovirus E1A makes extensive connections with the cellular protein interaction network. By doing so, E1A can manipulate many cellular programs, including cell cycle progression. Through these reprogramming events, E1A functions as a growth-promoting oncogene and has been used extensively to investigate mechanisms contributing to oncogenesis. Nevertheless, it remains unclear how the C-terminal region of E1A contributes to oncogenic transformation. Although this region is required for transformation in cooperation with E1B, it paradoxically suppresses transformation in cooperation with activated Ras. Previous analysis has suggested that the interaction of E1A with CtBP plays a pivotal role in both activities. However, some C-terminal mutants of E1A retain CtBP binding and yet exhibit defects in transformation, suggesting that other targets of this region are also necessary. To explore the roles of these additional factors, we performed an extensive mutational analysis of the C terminus of E1A. We identified key residues that are specifically required for binding all known targets of the C terminus of E1A. We further tested each mutant for the ability to both localize to the nucleus and transform primary rat cells in cooperation with E1B-55K or Ras. Interaction of E1A with importin α3/Qip1, dual-specificity tyrosine-regulated kinase 1A (DYRK1A), HAN11, and CtBP influenced transformation with E1B-55K. Interestingly, the interaction of E1A with DYRK1A and HAN11 appeared to play a role in suppression of transformation by activated Ras whereas interaction with CtBP was not necessary. This unexpected result suggests a need for revision of current models and provides new insight into transformation by the C terminus of E1A. 相似文献
64.
Gul N. Shah Yoichi Morofuji William A. Banks Tulin O. Price 《Biochemical and biophysical research communications》2013
Hyperglycemia-induced oxidative stress leads to diabetes-associated damage to the microvasculature of the brain. Pericytes in close proximity to endothelial cells in the brain microvessels are vital to the integrity of the blood–brain barrier and are especially susceptible to oxidative stress. According to our recently published results, streptozotocin-diabetic mouse brain exhibits oxidative stress and loose pericytes by twelve weeks of diabetes, and cerebral pericytes cultured in high glucose media suffer intracellular oxidative stress and apoptosis. Oxidative stress in diabetes is hypothesized to be caused by reactive oxygen species (ROS) produced during hyperglycemia-induced enhanced oxidative metabolism of glucose (respiration). To test this hypothesis, we investigated the effect of high glucose on respiration rate and ROS production in mouse cerebral pericytes. Previously, we showed that pharmacological inhibition of mitochondrial carbonic anhydrases protects the brain from oxidative stress and pericyte loss. The high glucose-induced intracellular oxidative stress and apoptosis of pericytes in culture were also reversed by inhibition of mitochondrial carbonic anhydrases. Therefore, we extended our current study to determine the effect of these inhibitors on high glucose-induced increases in pericyte respiration and ROS. We now report that both the respiration and ROS are significantly increased in pericytes challenged with high glucose. Furthermore, inhibition of mitochondrial carbonic anhydrases significantly slowed down both the rate of respiration and ROS production. These data provide new evidence that pharmacological inhibitors of mitochondrial carbonic anhydrases, already in clinical use, may prove beneficial in protecting the brain from oxidative stress caused by ROS produced as a consequence of hyperglycemia-induced enhanced respiration. 相似文献
65.
Few species of plant‐parasitic nematodes (PPN) are currently recognised as invasive but this is largely because of insufficient investigation and recognition. We compared the characteristics of PPN with those of invasive species generally, using the propagule pressure, abiotic and biotic factors (PAB) framework. Most PPN had many of the characteristics of invasive species and hence have the potential to become invasive. The most common characteristics included: adaptations for human mediated dispersal; multiple entry pathways; microscopic size; large number of propagules; high fecundity; many or cosmopolitan hosts; short lifecycle; ability to survive harsh or unfavourable conditions; ability to vary sex ratios; and ability to overcome host plant resistance. Information is lacking for many characteristics of many species and their impacts remain unquantified, which leaves some important unanswered questions and challenges for assessing PPN as invasive species. However many economically important PPN species have not been recognised as invasive, even when most of the known characteristics and data suggests they should be. 相似文献
66.
The diverse pollen morphology of fourteen species of the genus Eperua is described and illustrated using light, scanning electron and transmission electron microscopy. Six pollen types are described and a key for their identification is provided. A cladistic analysis was carried out using macromorphological and palynological characters to form a hypothesis of relationships between taxa. The pollen morphology is discussed with regard to systematic relationships, function and phylogenetic significance of certain pollen morphological structures within the genus. 相似文献
67.
The Burseraceae are a medium‐sized family in which 18 genera are currently recognised. They are the subject of a long‐term project to describe the pollen morphology from light, scanning electron and transmission electron microscopy. The pollen morphology of tribe Protieae has been published, as well as an account of the pollen of the African taxa in the family. Pollen data for the other two tribes, Bursereae and Canarieae, are more or less complete. The pollen of all the genera have been examined, with the exception of the recently described Pseudodacryodes Pierlot for which, currently, there is no pollen material available. This paper summarises the results. There is considerable variation in exine and aperture features between, and occasionally within, the genera and 14 major pollen types are defined, including two previously undescribed types: ‘Canarium oleiferum’ and ‘Canarium gracile’. The distribution of pollen characteristics throughout the family is compared with previously published tribal and subtribal groupings, as well as with current ideas of generic relationships from molecular analyses. Comparisons show notable congruence of pollen data with molecular data. To some extent pollen morphology is different for each of the subtribes. Nevertheless, there are some notable exceptions, for example, the pollen of Garuga and Boswellia are remarkably similar, although Garuga has been included, somewhat tenuously, in tribe Protieae, and Boswellia is included in tribe Bursereae, subtribe Boswelliinae. In a recent molecular tree Garuga and Boswellia appear to be closely related, and this supports the conclusion, based on several macromorphological characters as well as pollen, that Garuga should be transferred to tribe Bursereae. 相似文献
68.
69.
G M Matthews M Lefebure M A Doyle J Shortt J Ellul M Chesi K-M Banks E Vidacs D Faulkner P Atadja P L Bergsagel R W Johnstone 《Cell death & disease》2013,4(9):e798
Multiple myeloma (MM) is an incurable malignancy with an unmet need for innovative treatment options. Histone deacetylase inhibitors (HDACi) are a new class of anticancer agent that have demonstrated activity in hematological malignancies. Here, we investigated the efficacy and safety of HDACi (vorinostat, panobinostat, romidepsin) and novel combination therapies using in vitro human MM cell lines and in vivo preclinical screening utilizing syngeneic transplanted Vk*MYC MM. HDACi were combined with ABT-737, which targets the intrinsic apoptosis pathway, recombinant human tumour necrosis factor-related apoptosis-inducing ligand (rhTRAIL/MD5-1), that activates the extrinsic apoptosis pathway or the DNA methyl transferase inhibitor 5-azacytidine. We demonstrate that in vitro cell line-based studies provide some insight into drug activity and combination therapies that synergistically kill MM cells; however, they do not always predict in vivo preclinical efficacy or toxicity. Importantly, utilizing transplanted Vk*MYC MM, we report that panobinostat and 5-azacytidine synergize to prolong the survival of tumor-bearing mice. In contrast, combined HDACi/rhTRAIL-based strategies, while efficacious, demonstrated on-target dose-limiting toxicities that precluded prolonged treatment. Taken together, our studies provide evidence that the transplanted Vk*MYC model of MM is a useful screening tool for anti-MM drugs and should aid in the prioritization of novel drug testing in the clinic. 相似文献
70.
Janaka?WeragodaEmail author Rohini?Seneviratne Manuj?C.?Weerasinghe SM?Wijeyaratne 《BMC research notes》2016,9(1):508