329 research outputs found
Evaluation Of Present Day Treatment Of Peptic Ulcer
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111139/1/j.1532-5415.1953.tb01110.x.pd
Novel Biomarkers in the Management of HPV-Positive & -Negative Oropharyngeal Carcinoma
Human Papillomavirus (HPV)-related oropharyngeal carcinoma is considered to be in the early stages of an epidemic. A marked rise in the incidence of this sexually-transmissible cancer has captured the public interest, and much debate exists over both the prophylactic and therapeutic strategies currently employed to manage this healthcare priority.
HPV-positive oropharyngeal carcinoma is associated with highly favourable oncological outcomes. Clinical attention over recent years has been paid to the potential de-escalation of therapy in order to account for the disease’s favourable prognosis, in addition to reducing therapeutic burden in a well-prognosticating, younger patient cohort, for which consequences of radical chemo-radiotherapy strategies may disproportionately impact on longer-term quality of life. Whilst optimising the management of the ever-increasing proportion of HPV-positive oropharyngeal carcinomas is desirable and highly justifiable, it appears the poorer prognosticating HPV-negative oropharyngeal carcinoma has at least in part become overlooked.
Oropharyngeal carcinoma is unique in comparison to many other established HPV-related cancers inasmuch as a clear HPV-negative subset exists, to which established aetiological factors (tobacco smoking and alcohol consumption) strongly correlate. For most other HPV-related carcinomas, such as cervical, anal and penile, tumours classified as HPV-negative are either regarded as potentially-virus containing, or else cannot be correlated to a definitive aetiological agent. Comparison of HPV-positive and -negative oropharyngeal carcinoma therefore offers unprecedented insight into the biological significance of each aetiological agent, and how prognostication of each disease may relate to tumour behaviour at a molecular level. Whilst improved outcomes may be attributable in part to greater radio-sensitivity due to preservation of key wild-type genes in HPV-positive tumours, more comprehensive biological differences are likely to underpin the overall behaviour of disease – indeed, surgical outcomes are also favourable in HPV-positive disease.
This thesis explores the potential for the tumour microenvironment to differ between HPV-positive and -negative disease. We hypothesised that due to the strictly epitheliotropic nature of the Human Papillomavirus, activation of the tumour microenvironment would potentially be suppressed in order to avoid host clearance of pathogen during the natural history of viral infection, whereas penetrating carcinogens linked to tobacco smoking and alcohol consumption may either directly derange the stroma or, less contentiously, induce an increased mutational load which in turn in turn may offer greater opportunity for tumour evolution towards deranged microenvironmental signalling.
A 2D tissue culture model of the tumour microenvironment was created and used to test the hypothesis of a difference in microenvironmental interactions between HPV-positive versus HPV-negative disease, and normal stroma. Confirmation of an increase in migration-inducing signals from the modelled normal fibroblast stroma in HPV-negative disease led to further investigation at a molecular level using cytokine array technology. Further ELISA quantification and recombinant protein dose-response analysis ultimately identified Human Hepatocyte Growth Factor (HGF) as a primary candidate molecule for driving the additional migration observed in response to activated stroma. IL-6, co-secreted with HGF by stimulated fibroblasts, was also found to have a supporting role through the co-induction of STAT3. Final confirmation of HGF’s principal role in inducing HPV-negative tumour migration was undertaken using the clinically relevant c-Met inhibitors, foretinib & INCB28060 (recently rebranded as capmatinib)
The relationship of individual comorbid chronic conditions to diabetes care quality.
ObjectiveMultimorbidity affects 26 million persons with diabetes, and care for comorbid chronic conditions may impact diabetes care quality. The aim of this study was to determine which chronic conditions were related to lack of achievement or achievement of diabetes care quality goals to determine potential targets for future interventions.Research design and methodsThis is an exploratory retrospective analysis of electronic health record data for 23 430 adults, aged 18-75, with diabetes who were seen at seven Midwestern US health systems. The main outcome measures were achievement of six diabetes quality metrics in the reporting year, 2011 (glycated haemoglobin (HbA1c) control and testing, low-density lipoprotein control and testing, blood pressure control, kidney testing). Explanatory variables were 62 chronic condition indicators. Analyses were adjusted for baseline patient sociodemographic and healthcare utilization factors.ResultsThe 62 chronic conditions varied in their relationships to diabetes care goal achievement for specific care goals. Congestive heart failure was related to lack of achievement of cholesterol management goals. Obesity was related to lack of HbA1c and BP control. Mental health conditions were related to both lack of achievement and achievement of different care goals. Three conditions were related to lack of cholesterol testing, including congestive heart failure and substance-use disorders. Of 17 conditions related to achieving control goals, 16 were related to achieving HbA1c control. One-half of the comorbid conditions did not predict diabetes care quality.ConclusionsFuture interventions could target patients at risk for not achieving diabetes care for specific care goals based on their individual comorbidities
Replication fork regression in vitro by the Werner syndrome protein (WRN): Holliday junction formation, the effect of leading arm structure and a potential role for WRN exonuclease activity
The premature aging and cancer-prone disease Werner syndrome stems from loss of WRN protein function. WRN deficiency causes replication abnormalities, sensitivity to certain genotoxic agents, genomic instability and early replicative senescence in primary fibroblasts. As a RecQ helicase family member, WRN is a DNA-dependent ATPase and unwinding enzyme, but also possesses strand annealing and exonuclease activities. RecQ helicases are postulated to participate in pathways responding to replication blockage, pathways possibly initiated by fork regression. In this study, a series of model replication fork substrates were used to examine the fork regression capability of WRN. Our results demonstrate that WRN catalyzes fork regression and Holliday junction formation. This process is an ATP-dependent reaction that is particularly efficient on forks containing single-stranded gaps of at least 11–13 nt on the leading arm at the fork junction. Importantly, WRN exonuclease activity, by digesting the leading daughter strand, enhances regression of forks with smaller gaps on the leading arm, thus creating an optimal structure for regression. Our results suggest that the multiple activities of WRN cooperate to promote replication fork regression. These findings, along with the established cellular consequences of WRN deficiency, strongly support a role for WRN in regression of blocked replication forks
Replication Fork Regression \u3cem\u3eIn Vitro\u3c/em\u3e by the Werner Syndrome Protein (WRN): Holliday Junction Formation, the Effect of Leading Arm Structure and a Potential Role for WRN Exonuclease Activity
The premature aging and cancer-prone disease Werner syndrome stems from loss of WRN protein function. WRN deficiency causes replication abnormalities, sensitivity to certain genotoxic agents, genomic instability and early replicative senescence in primary fibroblasts. As a RecQ helicase family member, WRN is a DNA-dependent ATPase and unwinding enzyme, but also possesses strand annealing and exonuclease activities. RecQ helicases are postulated to participate in pathways responding to replication blockage, pathways possibly initiated by fork regression. In this study, a series of model replication fork substrates were used to examine the fork regression capability of WRN. Our results demonstrate that WRN catalyzes fork regression and Holliday junction formation. This process is an ATP-dependent reaction that is particularly efficient on forks containing single-stranded gaps of at least 11–13 nt on the leading arm at the fork junction. Importantly, WRN exonuclease activity, by digesting the leading daughter strand, enhances regression of forks with smaller gaps on the leading arm, thus creating an optimal structure for regression. Our results suggest that the multiple activities of WRN cooperate to promote replication fork regression. These findings, along with the established cellular consequences of WRN deficiency, strongly support a role for WRN in regression of blocked replication forks
Temperature-Controlled Mechanochemistry for the Nickel-Catalyzed Suzuki-Miyaura-Type Coupling of Aryl Sulfamates via Ball Milling and Twin-Screw Extrusion
The use of temperature-controlled mechanochemistry to enable the mechanochemical nickel-catalyzed Suzuki-Miyaura coupling is herein described. Transitioning from a capricious room-temperature protocol, through to a heated, PID-controlled programmable jar heater manifold was required to deliver an efficient method for the coupling of aryl sulfamates (derived from ubiquitous phenols) and aryl boronic acid species. Furthermore, this process is conducted using a base-metal nickel catalyst, in the absence of bulk solvent, and in the absence of air/moisture sensitive reaction set-ups. This methodology is showcased through translation to large-scale twin-screw extrusion methodology enabling 200-fold scale increase, producing decagram quantities of C-C coupled material
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