102 resultados para Disease and pest resistance - Genetic aspects
Resumo:
The relatively high elastic modulus coupled with the presence of toxic vanadium (V) in Ti6Al4 V alloy has long been a concern in orthopaedic applications. To solve the problem, a variety of non-toxic and low modulus beta-titanium (beta-Ti) alloys have been developed. Among the beta-Ti alloy family, the quaternary Ti-Nb-Zr-Ta (TNZT) alloys have received the highest attention as a promising replacement for Ti6Al4 V due to their lower elastic modulus and outstanding long term stability against corrosion in biological environments. However, the inferior wear resistance of TNZT is still a problem that must be resolved before commercialising in the orthopaedic market. In this work, a newly-developed laser surface treatment technique was employed to improve the surface properties of Ti-35.3Nb-7.3Zr-5.7Ta alloy. The surface structure and composition of the laser-treated TNZT surface were examined by grazing incidence x-ray diffraction (GI-XRD) and x-ray photoelectron spectroscopy (XPS). The wear and corrosion resistance were evaluated by pin-on-plate sliding test and anodic polarisation test in Hanks’ solution. The experimental results were compared with the untreated (or base) TNZT material. The research findings showed that the laser surface treatment technique reported in this work can effectively improve the wear and corrosion resistance of TNZT.
Resumo:
Anecdotal evidence has it that when Dublin’s venereal disease hospital closed its doors for the last time in the 1950s, its administrative staff began to burn its records, starting with the most recent. This attempt to conceal the results of sexual profligacy is perhaps understandable in the rarefied climate of mid-century Catholic Ireland. However, the sense of shame attached to this institution has been pervasive. For example, of all Dublin’s major hospitals, the lock hospital remains the only one without a dedicated history. And, throughout its two centuries of existence, the ‘lock’ had often been a site of controversy and approbation.
The institution began in the eighteenth century as the most peripatetic, poor relation of the city’s voluntary hospitals, wandering indiscriminately through a series of temporary premises before finally achieving a permanent home and official recognition as a military-sponsored medical hospital in 1792. It also gained architectural extensions by both Richard and Francis Johnston and in the following decades. This new-found status and a growing re-conceptualisation of venereal disease as a legitimate medical problem rather than a matter of morality was, however, somewhat compromised by the choice of site at Townsend Street. The institution occupied a hidden part of city, appropriating the vacated home of the Hospital for Incurables, another marginalised group whose presence in the city had been viewed through the lens of superstition and fear. For the rest of its existence, the lock hospital would share this experience occupying a nebulous position between medicine and morality; disease and sin.
Using what’s left of the hospital’s records and a series of original architectural drawings, this paper discusses the presence and role of the lock hospital in the city in the eighteenth and early nineteenth century, tracking how changes in its administration and architectural form reflected wider attitudes towards disease, sexuality and gender in Georgian Dublin.
Resumo:
The frog skin host-defense peptide tigerinin-1R stimulates insulin release in vitro and improves glucose tolerance and insulin sensitivity in animal models of type 2 diabetes. This study extends these observation by investigating the molecular mechanisms of action underlying the beneficial metabolic effects of the analogue [Arg4]tigerinin-1R in mice with diet induced obesity, glucose intolerance and insulin resistance. The study also investigates the electrophysiological effects of the peptide on KATP and L-type Ca2+ channels in BRINBD11 clonal β cells. Non-fasting plasma glucose and glucagon concentrations were significantly (P<0.05) decreased and plasma insulin increased by twice daily treatment with [Arg4]tigerinin-1R (75 nmol.kg-1 body weight) for 28 days. Oral and intraperitoneal glucose tolerance were significantly (P < 0.05) improved accompanied by enhanced secretion and action of insulin. The peptide blocked KATP channels and, consistent with this, improved beta cell responses of isolated islets to a range of secretagogues. Peptide administration resulted in up-regulation of key functional genes in islets involved insulin secretion (Abcc8, Kcnj11, Cacna1c and Slc2a2) and in skeletal muscle involved with insulin action (Insr, Irs1, Pdk1, Pik3ca, and Slc2a4). These observations encourage further development of tigerinin-1R analogues for the treatment of patients with type 2 diabetes.
Resumo:
Background A developing body of evidence has provided valuable insight into the experiences of caregivers of people with motor neuron disease; however, understandings of how best to support caregivers remain limited.
Aim This study sought to understand concepts related to the motor neuron disease caregiver experience which could inform the development of supportive interventions.
Design A qualitative thematic analysis of a one-off semistructured interview with caregivers was undertaken.
Setting/participants Caregivers of people with motor neuron disease were recruited from a progressive neurological diseases clinic in Melbourne, Australia.
Results 15 caregivers participated. Three key themes were identified: (1) The Thief: the experience of loss and grief across varied facets of life; (2) The Labyrinth: finding ways to address ever changing challenges as the disease progressed; (3) Defying fate: being resilient and hopeful as caregivers tried to make the most of the time remaining.
Conclusions Caregivers are in need of more guidance and support to cope with experiences of loss and to adapt to changeable care giving duties associated with disease progression. Therapeutic interventions which target these experiences of loss and change are worth investigation.
Resumo:
Background: Adherence to treatment is low in bronchiectasis and is associated with poorer health outcomes. Factors affecting adherence decisions have not been explored in patients with bronchiectasis.
Objective: We aimed to explore patients' perspectives on adherence, factors affecting adherence decision making and to develop a conceptual model explaining this decision-making process in adults with bronchiectasis.
Methods: Adults with bronchiectasis participated in one-to-one semi-structured interviews. Interviews were audio-recorded, transcribed verbatim and analysed independently by two researchers using thematic analysis. Data from core themes were extracted, categorized into factors affecting adherence decision making and used to develop the conceptual model.
Results: Participants' beliefs about treatment, the practical aspects of managing treatment, their trust in health-care professionals and acceptance of disease and treatment were important aspects of treatment adherence. The conceptual model demonstrated that adherence decisions were influenced by participants' individual balance of barriers and motivating factors (treatment-related, disease-related, health-care-related, personal and social factors).
Conclusion: Adherence decision-making in bronchiectasis is complex, but there is the potential to enhance adherence by understanding patients' specific barriers and motivators to adherence and using this to tailor adherence strategies to individual patients and treatments. © 2014 John Wiley & Sons Ltd.
Resumo:
Compassion is at the forefront of national and international healthcare policy, practice and educational debates as a result of a series of recent reports (Mid Staffordshire NHS Foundation Trust Inquiry, 2010, Lown et al 2011, Mannion, 2014). Arguably, this emphasis on compassion is in juxtaposition to an increasingly complex technological healthcare system focused upon outcomes, efficiency, productivity and competence. Within this fast paced and time pressured environment innovative strategies are required to cultivate and sustain compassion among healthcare professionals.
Understanding the person’s experience of illness and making an emotional connection are key processes in cultivating compassion (Dewar, 2013). The exponential growth in unsolicited patient narratives has the potential to provide invaluable insight into what matters to patients and their experience of illness. For many patients these stories ‘reclaim’ their illnesses from the traditional biomedical model of disease and reveal otherwise hidden aspects of their experience. The content though freely accessible, is however unedited and lacks safeguards in relation to the quality or accuracy of the information provided. Despite these concerns, healthcare professionals are now challenged to pay attention to these unsolicited patient stories and to consider how they can inform and improve patient care.
This paper discusses the use of online patient narratives in undergraduate nurse education to cultivate compassion. Critical analysis of online patient narratives is advocated as a potential educational strategy to cultivate compassion among future health care professionals.
References
Dewar,B. (2013) Cultivating compassionate care Nursing Standard 27, (34) 48-55
Lown B, Rosen J, Martilla J.(2011) An agenda for improving compassionate care: a survey shows about half of patients say such care is missing. Health Affairs (Millwood) 30, 1772–8.
Mannion,R. (2014) Enabling compassionate healthcare: perils, prospects and perspectives International Journal of Health Policy and Management 2, 115-7
Mid Staffordshire NHS Foundation Trust Inquiry (2010). Independent Inquiry into care provided by Mid Staffordshire NHS Foundation London: Stationery Office.
Resumo:
There is growing evidence that insects in high-density populations invest relatively more in pathogen resistance than those in low-density populations (i.e. density-dependent prophylaxis). Such increases in resistance are often accompanied by cuticular melanism, which is characteristic of the high-density form of many phase polyphenic insects. Both melanism and pathogen resistance involve the prophenoloxidase enzyme system. In this paper the link between resistance, melanism and phenoloxidase activity is examined in Spodoptera lanae. In S. exempta, cuticular melanism was positively correlated with phenoloxidase activity in the cuticle, haemolymph and midgut. Melanic S. exempta larvae were found to melanize a greater proportion of eggs of the ectoparasitoid Euplectrus laphygmae than non-melanic larvae, and melanic S. littoralis were more resistant to the entomopathogenic fungus Beauveria bassiana (in S. exempta the association between melanism and fungal resistance was non-signficant). These results strengthen the link between melanism and disease resistance and implicate the involvement of phenoloxidase.
Resumo:
Diabetes is increasing at daunting rates worldwide, and approximately 40% of affected individuals will develop kidney complications. Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease, and there are significant healthcare costs providing appropriate renal replacement therapies to affected individuals. For several decades, investigators have sought to discover inherited risk factors and biomarkers for DKD. In recent years, advances in high-throughput laboratory techniques and computational analyses, coupled with the establishment of multicenter consortia, have helped to identify genetic loci that are replicated across multiple populations. Several genome-wide association studies (GWAS) have been conducted for DKD with further meta-analysis of GWAS and comprehensive ”single gene” meta-analyses now published. Despite these efforts, much of the inherited predisposition to DKD remains unexplained. Meta-analyses and integrated–omics pathway studies are being used to help elucidate underlying genetic risks. Epigenetic phenomena are increasingly recognized as important drivers of disease risk, and several epigenome-wide association studies have now been completed. This review describes key findings and ongoing genetic and epigenetic initiatives for DKD.
Resumo:
Background: Late-onset Alzheimer's disease (AD) is heritable with 20 genes showing genome-wide association in the International Genomics of Alzheimer's Project (IGAP). To identify the biology underlying the disease, we extended these genetic data in a pathway analysis.
Methods: The ALIGATOR and GSEA algorithms were used in the IGAP data to identify associated functional pathways and correlated gene expression networks in human brain.
Results: ALIGATOR identified an excess of curated biological pathways showing enrichment of association. Enriched areas of biology included the immune response (P = 3.27 X 10(-12) after multiple testing correction for pathways), regulation of endocytosis (P = 1.31 X 10(-11)), cholesterol transport (P = 2.96 X 10(-9)), and proteasome-ubiquitin activity (P = 1.34 X 10(-6)). Correlated gene expression analysis identified four significant network modules, all related to the immune response (corrected P = .002-.05).
Conclusions: The immime response, regulation of endocytosis, cholesterol transport, and protein ubiquitination represent prime targets for AD therapeutics. (C) 2015 Published by Elsevier Inc. on behalf of The Alzheimer's Association.
Resumo:
The biological role of steroid 5 alpha-reductase isozymes (encoded by the SRD5A1 and SRD5A2 genes) and angiogenic factors that play important roles in the pathogenesis and vascularization of prostate cancer (PC) is poorly understood. The sub-cellular expression of these isozymes and vascular endothelial growth factor (VEGF) in PC tissue microarrays (n=62) was examined using immunohistochemistry. The effect of SRD5A inhibition on the angiogenesis pathway genes in PC was also examined in prostate cell lines, LNCaP, PC3, and RWPE-1, by treating them with the SRD5A inhibitors finasteride and dutasteride, followed by western blot, quantitative PCR, and ELISA chip array techniques. In PC tissues, nuclear SRD5A1 expression was strongly associated with higher cancer Gleason scores (P=0.02), higher cancer stage (P=0.01), and higher serum prostate specific antigen (PSA) levels (P=0.01), whereas nuclear SRD5A2 expression was correlated with VEGF expression (P=0.01). Prostate tumor cell viability was significantly reduced in dutasteride-treated PC3 and RWPE-1 cells compared with finasteride-treated groups. Expression of the angiogenesis pathway genes transforming growth factor beta 1 (TGFB1), endothelin (EDN1), TGF alpha (TGFA), and VEGFR1 was upregulated in LNCaP cells, and at least 7 out of 21 genes were upregulated in PC3 cells treated with finasteride (25 mu M). Our findings suggest that SRD5A1 expression predominates in advanced PC, and that inhibition of SRD5A1 and SRD5A2 together was more effective in reducing cell numbers than inhibition of SRD5A2 alone. However, these inhibitors did not show any significant difference in prostate cell angiogenic response. Interestingly, some angiogenic genes remained activated after treatment, possibly due to the duration of treatment and tumor resistance to inhibitors. Endocrine-Related Cancer (2010) 17 757-770
Resumo:
PURPOSE To characterise subtypes of fundus autofluorescence (AF), the progression of retinal atrophy and correlate these findings with genotype in Stargardt Disease. METHODS Full clinical examination and AF imaging was undertaken in 68 patients with Stargardt Disease. The baseline data were compared with those at follow-up. Patients were classified into three AF subtypes: type 1 had a localised low signal at the fovea surrounded by a homogeneous background; type 2 had a localised low signal at the macula surrounded by a heterogeneous background with numerous foci of abnormal signal; type 3 had multiple low signal areas at the posterior pole with a heterogeneous background. At baseline, there were 19 patients with type 1, 41 with type 2, and 8 with type 3. The areas of reduced AF signal were measured and rate of atrophy enlargement (RAE) was calculated as the difference of the atrophy size over time (mm2) divided by the follow-up interval (yrs). Molecular screening of ABCA4 was undertaken. RESULTS The mean follow-up interval was 9.1 years. 42% of type 1 progressed to type 2, and 12% of type 2 progressed to type 3. RAE (mm2/yr) based upon baseline AF subtypes was significantly different; 0.06 in type 1, 0.67 in type 2, and 4.37 in type 3. ABCA4 variants were identified in 57 patients. There was a significant association between AF subtype and genotype. CONCLUSIONS The AF pattern at baseline influences the enlargement of atrophy over time and has genetic correlates. These data are likely to assist in the provision of counselling on prognosis in Stargardt Disease and be valuable for future clinical trials.