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121.
Background
The kallikrein-kinin system (KKS) is an endogenous pathway involved in angiogenesis and tumourigenesis, both vital for cancer growth and progression.Objectives
To investigate the effect of two bradykinin receptor (B1R and B2R) agonists on growth and motility of prostate tumour (DU145) and micro-vascular endothelial cells (dMVECs).Methods
Increasing concentrations of selective B1R and B2R agonists were added to cultured cells. Cell proliferation and migration were assessed using the 3-[4,5 dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and modified Boyden Chamber assays, respectively. Where significant stimulation was found, the influence of an antagonist was also investigated.Results
Neither growth nor motility of endothelial cells was affected by either agonist. In DU145 cells, while the B2R agonist was without any significant effect, the B1R agonist stimulated proliferation and migration at concentrations of 10nM and 50nM respectively. Further, this effect was abrogated when cells were pre-incubated with a B1R antagonist.Conclusions
Unlike the physiologically-active B2R, the pathologically-inducible B1R may be implicated in prostate tumourigenic events. The involvement of the KKS in malignant prostate pathology supports on-going exploration of bradykinin receptor antagonists as target candidates in the development of alternate approaches to cancer therapy. 相似文献122.
KH Neppelenbroek RS Seó VM Urban S Silva LN Dovigo JH Jorge NH Campanha 《Oral diseases》2014,20(4):329-344
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species. 相似文献
123.
LL Patton 《Oral diseases》2014,20(3):223-225
Over the last 30 years, there have been significant advances in our scientific knowledge of HIV disease, including prevention, detection, medical management, and attempts at cure. Investigations and observations of the oral cavity in individuals with HIV disease have contributed substantially to scientific discovery and innovation. Challenges remain for managing existing and emerging oral diseases associated with HIV and understanding the contribution of latent oral mucosal reservoirs to HIV eradication. 相似文献
124.
125.
Cardiovascular implantable electronic device (CIED) implantation indications have greatly increased over the past decade, with use of pacemakers and implantable cardiac defibrillators now growing more common even in athletes. Management of CIEDs in this subgroup is of greater complexity due to augmented physical stressors, a longer exposure time to system components in a younger population, and less common, highly clinically variable underlying cardiac pathologies. We will review management issues specific to CIED therapy, sudden cardiac death, and consensus recommendations for physical activity. 相似文献
126.
127.
Sarah M. McDonald Kristin Davis John K. McAllen David J. Spiro John T. Patton 《Infection, genetics and evolution》2011,11(7):1586-1594
Group A human rotaviruses (RVs) remain the most frequently detected viral agents associated with acute gastroenteritis in infants and young children. Despite their medical importance, relatively few complete genome sequences have been determined for commonly circulating G/P-type strains (i.e., G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8]). In the current study, we sequenced the genomes of 11 G4P[8] isolates from stool specimens that were collected in Washington, DC during the years of 1974–1991. We found that the VP7–VP4–VP6–VP1–VP2–VP3–NSP1–NSP2–NSP3–NSP4–NSP5/6-encoding genes of all 11 G4P[8] RVs have the genotypes of G4-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1. By constructing phylogenetic trees for each gene, extensive intra-genotypic diversity was revealed among the G4P[8] RVs, and new sub-genotype gene alleles were identified. Several of these alleles are nearly identical to those of G3P[8] isolates previously sequenced from this same Washington, DC collection, strongly suggesting that the RVs underwent gene reassortment. On the other hand, we observed that some G4P[8] RVs exhibit completely different allele-based genome constellations, despite being collected during the same epidemic season; there was no evidence of gene reassortment between these strains. This observation extends our previous findings and supports the notion that stable, genetically-distinct clades of human RVs with the same G/P-type can co-circulate in a community. Interestingly, the sub-genotype gene alleles found in some of the DC RVs share a close evolutionary relationship with genes of more contemporary human strains. Thus, archival human RVs sequenced in this study might represent evolutionary precursors to modern-day strains. 相似文献
128.
Susana R. Patton Sally Eder Jennifer Schwab Christine M. Sisson 《Journal of pediatric health care》2010,24(6):365-371
ObjectiveInjection site rotation is an important component of insulin administration and is helpful in preventing lipodystrophy in type 1 diabetes (T1DM). We examined the number of injection/infusion sites (sites) used by youth with T1DM and their perceived barriers to using new sites for insulin.MethodsTwo hundred and one youth with T1DM completed a 24-item survey about site rotation practices and barriers to site rotation during a routine diabetes appointment.ResultsFifteen percent of youth reported using at least four distinct sites in their rotation plan, while 22% reported using only one site. A negative correlation was found between number of sites used and the number of perceived barriers endorsed by youth on multiple daily injections. Fear of pain was the most common barrier endorsed by youth.ConclusionMany youth with T1DM may not adhere to an adequate site rotation plan. Regular assessment of insulin sites and counseling regarding adequate site rotation is needed when managing diabetes in youth. Relaxation and distraction may help to reduce youths' fear of pain when rotating to new insulin sites. 相似文献
129.
Wendy Swift Carolyn Coffey John B. Carlin Louisa Degenhardt Bianca Calabria & George C. Patton 《Addiction (Abingdon, England)》2009,104(5):806-814
Aims To examine whether moderation of cannabis use among adolescent cannabis users is associated with reductions in cannabis use frequency and risk of dependence in young adulthood.
Design Ten-year representative cohort study with six surveys in adolescence (mean age 14.9–17.4 years) and two in young adulthood (mean age 20.7 and 24.1 years).
Participants Inception cohort of 1943 Victorian secondary school students (96% response rate), with 1520 (78% of adolescent participants) interviewed in the final wave.
Measurements Participants were classified into six groups according to the maximum level of adolescent use and the extent of subsequent moderation in such use: non-users, occasional to abstinence, occasional persisting, weekly to abstinence, weekly to occasional and weekly persisting. Outcome measures were weekly+ cannabis use and DSM-IV cannabis dependence at 20 and 24 years.
Findings Thirty-one per cent reported cannabis use during adolescence. Most adolescent users had moderated their use: from occasional to abstinence (71% of occasional users), weekly to abstinence or weekly to occasional (28% and 48% of weekly+ users, respectively). By age 24, both occasional use groups were at similar, elevated risk of regular and dependent cannabis use compared to non-users. Weekly+ adolescent users were at greatest risk of these outcomes, although the weekly to abstinence group exhibited lower risk than those in the weekly persisting and weekly to occasional groups, who were at similar risk.
Conclusions While many young people have dynamic cannabis use patterns, a pattern of moderating adolescent cannabis use was associated with less risk of later problematic use than among those persisting, but risks were still elevated substantially compared with never-users. 相似文献
Design Ten-year representative cohort study with six surveys in adolescence (mean age 14.9–17.4 years) and two in young adulthood (mean age 20.7 and 24.1 years).
Participants Inception cohort of 1943 Victorian secondary school students (96% response rate), with 1520 (78% of adolescent participants) interviewed in the final wave.
Measurements Participants were classified into six groups according to the maximum level of adolescent use and the extent of subsequent moderation in such use: non-users, occasional to abstinence, occasional persisting, weekly to abstinence, weekly to occasional and weekly persisting. Outcome measures were weekly+ cannabis use and DSM-IV cannabis dependence at 20 and 24 years.
Findings Thirty-one per cent reported cannabis use during adolescence. Most adolescent users had moderated their use: from occasional to abstinence (71% of occasional users), weekly to abstinence or weekly to occasional (28% and 48% of weekly+ users, respectively). By age 24, both occasional use groups were at similar, elevated risk of regular and dependent cannabis use compared to non-users. Weekly+ adolescent users were at greatest risk of these outcomes, although the weekly to abstinence group exhibited lower risk than those in the weekly persisting and weekly to occasional groups, who were at similar risk.
Conclusions While many young people have dynamic cannabis use patterns, a pattern of moderating adolescent cannabis use was associated with less risk of later problematic use than among those persisting, but risks were still elevated substantially compared with never-users. 相似文献
130.
C. H. Shiboski L. L. Patton J. Y. Webster-Cyriaque D. Greenspan R. S. Traboulsi M. Ghannoum R. Jurevic J. A. Phelan D. Reznik J. S. Greenspan The Oral HIV/AIDS Research Alliance Subcommittee of the AIDS Clinical Trial Group 《Journal of oral pathology & medicine》2009,38(6):481-488
The Oral HIV/AIDS Research Alliance (OHARA) is part of the AIDS Clinical Trials Group (ACTG), the largest HIV clinical trials organization in the world. Its main objective is to investigate oral complications associated with HIV/AIDS as the epidemic is evolving, in particular, the effects of antiretrovirals on oral mucosal lesion development and associated fungal and viral pathogens. The OHARA infrastructure comprises: the Epidemiologic Research Unit (at the University of California San Francisco), the Medical Mycology Unit (at Case Western Reserve University) and the Virology/Specimen Banking Unit (at the University of North Carolina). The team includes dentists, physicians, virologists, mycologists, immunologists, epidemiologists and statisticians. Observational studies and clinical trials are being implemented at ACTG-affiliated sites in the US and resource-poor countries. Many studies have shared end-points, which include oral diseases known to be associated with HIV/AIDS measured by trained and calibrated ACTG study nurses. In preparation for future protocols, we have updated existing diagnostic criteria of the oral manifestations of HIV published in 1992 and 1993. The proposed case definitions are designed to be used in large-scale epidemiologic studies and clinical trials, in both US and resource-poor settings, where diagnoses may be made by non-dental healthcare providers. The objective of this article is to present updated case definitions for HIV-related oral diseases that will be used to measure standardized clinical end-points in OHARA studies, and that can be used by any investigator outside of OHARA/ACTG conducting clinical research that pertains to these end-points. 相似文献