Prediction of bypass and separation-induced transition with an algebraic intermittency model

The paper discusses an algebraic intermittency model for prediction of bypass and separation-induced boundary layer transition. The transition model is coupled with a k-omega turbulence model. The transition model uses only local variables and is tuned for turbomachinery flows. For bypass transition, two effects in an attached pre-transitional boundary layer are modelled: damping of small-scale disturbances induced by the free stream and breakdown of the near-wall perturbed flow with generation of fine-scale turbulence. For separated flow, the model describes breakdown of a laminar free shear layer

LEADER-4

Objective: As glucagon-like peptide-1 receptor agonists lower blood pressure (BP) in type 2 diabetes mellitus (T2DM), we examined BP control in relation to targets set by international bodies prior to randomization in the Liraglutide Effect and Action in Diabetes: Evaluation of cardiovascular outcome Results (LEADER) trial. Methods: We analyzed baseline data from LEADER (NCT01179048), an ongoing phase 3B, randomized, double-blind, placebo-controlled cardiovascular outcomes trial examining the cardiovascular safety of the glucagon-like peptide-1 receptor agonist liraglutide in 9340 people with T2DM from 32 countries [age (all mean +/- SD) 64 +/- 7.2 years, BMI 32.5 +/- 6.3 kg/m2, duration of diabetes 12.7 +/- 8.0 years], all of whom were at high risk for cardiovascular disease (CVD). Results: A total of 81% (n = 7592) of participants had prior CVD and 90% (n = 8408) had a prior history of hypertension. Despite prescription of multiple antihypertensive agents at baseline, only 51% were treated to a target BP of less than 140/85 mmHg and only 26% to the recommended baseline BP target of less than 130/80 mmHg. In univariate analyses, those with prior CVD were prescribed more agents (P < 0.001) and had lower BP than those without (137 +/- 18.8/78 +/- 10.6 mmHg versus 140 +/- 17.7/80 +/- 9.9 mmHg; P < 0.001). In logistic regression analyses, residency in North America (64% treated to <140/85 mmHg; 38% treated to <130/80 mmHg) was the strongest predictor of BP control. Conclusion: These contemporary data confirm that BP remains insufficiently controlled in a large proportion of individuals with T2DM at high cardiovascular risk, particularly outside North America. Longitudinal data from the LEADER trial may provide further insights into BP control in relation to cardiovascular outcomes in this condition

Loss of heterozygosity for Rb locus and pRb immunostaining in laryngeal cancer: a clinicopathologic, molecular and immunohistochemical study.

Several risk factors for the development of laryngeal cancer have been identified, such as smoking and alcohol consumption, but the molecular mechanisms related to the carcinogenesis in the larynx remain under investigation. In this context, deregulations of the cell-cycle-controling mechanisms, Rb-pathway in particular, have been suggested to be involved in the pathogenesis of laryngeal carcinoma. Our purpose was to investigate 13q14 LOH and the expression of Rb protein and their possible prognostic value in laryngeal cancer. The group of 67 patients with laryngeal cancer, surgically treated with minimum 5 years observation, was multi-variously analysed. LOH for Rb was investigated by PCR-based techniques using two microsatellite markers, D13S263 and D13S126, flanking the Rb locus. Amplification products from each polymorphism were fractionated by denaturing gel electrophoresis and detected by audioradiography. Immunohistochemical staining of paraffin specimens of laryngeal cancers was supervised by the use of monoclonal mouse antibodies IgG1 (Anti-Human Retinoblastoma Gene Product of Dako) in dilution of 1:50. Inactivation of Rb protein was assumed to represent the expression in 0.05). There was a strong association between the loss of Rb and supraglottic localisation of tumour in the larynx (p0.05 respectively). The genetic data were correlated with the expression of the Rb protein (p=0.001). All tumours with Rb-LOH were immunohistochemically Rb-negative. Inactivation of Rb protein was observed in 9/67 cases (13.49%) and was significantly correlated with the polymorphism of cancer cells, but not with the histological grading. We also found the correlation between reduction of Rb protein and the size of primary tumour (T) (p=0.03) and local recurrence (p=0.035). There was no significant dependence between the level of Rb protein and other histopathological and clinical features (p>0.05). To conclude, analysis of 13q14 LOH enables the assessment of biology of laryngeal cancer and it can be a prognostic factor in overall survival. Immunohistochemical analysis of Rb protein expression in neoplastic cells made it easier to evaluate the mechanisms of cancerogenesis in laryngeal cancer and is closely related to genetic alteration in Rb locus

The epidemiology and management of severe hypertension

Hypertension guidelines stress that patients with severe hypertension (systolic blood pressure (BP)⩾180 or diastolic BP⩾110 mm Hg) require multiple drugs to achieve control and should have close follow-up to prevent adverse outcomes. However, little is known about the epidemiology or actual management of these patients. We retrospectively studied 59 207 veterans with hypertension. Patients were categorized based on their highest average BP over an 18-month period (1 July 1999 to 31 December 2000) as controlled (<140/90 mm Hg), mild (140–159/90–99 mm Hg), moderate (160–179/100–109 mm Hg) and severe hypertension. We examined severe hypertension prevalence, pattern, duration, associated patient characteristics, time to subsequent visit, percentage of visits with a medication increase, and final BP control and antihypertensive medication adequacy. Twenty-three per cent had ⩾1 visit with severe hypertension, 42% of whom had at least two such visits; median day with severe hypertension was 80 (range 1–548). These subjects were significantly older, more likely black, and with more comorbidities than other hypertension subjects. Medication increases occurred at 20% of visits with mild hypertension compared to 40% with severe hypertension; P<0.05). At study end, 76% of patients with severe hypertension remained uncontrolled; severe hypertension subjects with uncontrolled BP were less likely to be on adequate therapy than those with controlled BP (43.7 vs 45.4%). Among hypertensive veterans, severe hypertension episodes are common. Many subjects had relatively prolonged elevations, with older, sicker subjects at highest risk. Although, follow-up times are shorter and antihypertensive medication use greater in severe hypertension subjects, they are still not being managed aggressively enough. Interventions to improve providers' management of these high-risk patients are needed

Variations and inter-relationship in outcome from emergency admissions in England: a retrospective analysis of Hospital Episode Statistics from 2005-2010.

BACKGROUND: The quality of care delivered and clinical outcomes of care are of paramount importance. Wide variations in the outcome of emergency care have been suggested, but the scale of variation, and the way in which outcomes are inter-related are poorly defined and are critical to understand how best to improve services. This study quantifies the scale of variation in three outcomes for a contemporary cohort of patients undergoing emergency medical and surgical admissions. The way in which the outcomes of different diagnoses relate to each other is investigated. METHODS: A retrospective study using the English Hospital Episode Statistics 2005-2010 with one-year follow-up for all patients with one of 20 of the commonest and highest-risk emergency medical or surgical conditions. The primary outcome was in-hospital all-cause risk-standardised mortality rate (in-RSMR). Secondary outcomes were 1-year all-cause risk-standardised mortality rate (1 yr-RSMR) and 28-day all-cause emergency readmission rate (RSRR). RESULTS: 2,406,709 adult patients underwent emergency medical or surgical admissions in the groups of interest. Clinically and statistically significant variations in outcome were observed between providers for all three outcomes (p < 0.001). For some diagnoses including heart failure, acute myocardial infarction, stroke and fractured neck of femur, more than 20% of hospitals lay above the upper 95% control limit and were statistical outliers. The risk-standardised outcomes within a given hospital for an individual diagnostic group were significantly associated with the aggregated outcome of the other clinical groups. CONCLUSIONS: Hospital-level risk-standardised outcomes for emergency admissions across a range of specialties vary considerably and cross traditional speciality boundaries. This suggests that global institutional infra-structure and processes of care influence outcomes. The implications are far reaching, both in terms of investigating performance at individual hospitals and in understanding how hospitals can learn from the best performers to improve outcomes

Determinants of racial/ethnic differences in blood pressure management among hypertensive patients

BACKGROUND: Prior literature has shown that racial/ethnic minorities with hypertension may receive less aggressive treatment for their high blood pressure. However, to date there are few data available regarding the confounders of racial/ethnic disparities in the intensity of hypertension treatment. METHODS: We reviewed the medical records of 1,205 patients who had a minimum of two hypertension-related outpatient visits to 12 general internal medicine clinics during 7/1/01-6/30/02. Using logistic regression, we determined the odds of having therapy intensified by patient race/ethnicity after adjustment for clinical characteristics. RESULTS: Blacks (81.9%) and Whites (80.3%) were more likely than Latinos (71.5%) to have therapy intensified (P = 0.03). After adjustment for racial differences in the number of outpatient visits and presence of diabetes, there were no racial differences in rates of intensification. CONCLUSION: We found that racial/ethnic differences in therapy intensification were largely accounted for by differences in frequency of clinic visits and in the prevalence of diabetes. Given the higher rates of diabetes and hypertension related mortality among Hispanics in the U.S., future interventions to reduce disparities in cardiovascular outcomes should increase physician awareness of the need to intensify drug therapy more agressively in patients without waiting for multiple clinic visits, and should remind providers to treat hypertension more aggressively among diabetic patients

Association between mental health conditions and rehospitalization, mortality, and functional outcomes in patients with stroke following inpatient rehabilitation

<p>Abstract</p> <p>Background</p> <p>Limited evidence exists regarding the association of pre-existing mental health conditions in patients with stroke and stroke outcomes such as rehospitalization, mortality, and function. We examined the association between mental health conditions and rehospitalization, mortality, and functional outcomes in patients with stroke following inpatient rehabilitation.</p> <p>Methods</p> <p>Our observational study used the 2001 VA Integrated Stroke Outcomes database of 2162 patients with stroke who underwent rehabilitation at a Veterans Affairs Medical Center.</p> <p>Separate models were fit to our outcome measures that included 6-month rehospitalization or death, 6-month mortality post-discharge, and functional outcomes post inpatient rehabilitation as a function of number and type of mental health conditions. The models controlled for patient socio-demographics, length of stay, functional status, and rehabilitation setting.</p> <p>Results</p> <p>Patients had an average age of 68 years. Patients with stroke and two or more mental health conditions were more likely to be readmitted or die compared to patients with no conditions (OR: 1.44, p = 0.04). Depression and anxiety were associated with a greater likelihood of rehospitalization or death (OR: 1.33, p = 0.04; OR:1.47, p = 0.03). Patients with anxiety were more likely to die at six months (OR: 2.49, p = 0.001).</p> <p>Conclusions</p> <p>Patients with stroke with pre-existing mental health conditions may need additional psychotherapy interventions, which may potentially improve stroke outcomes post-hospitalization.</p

Part II, Provider perspectives: should patients be activated to request evidence-based medicine? a qualitative study of the VA project to implement diuretics (VAPID)

<p>Abstract</p> <p>Background</p> <p>Hypertension guidelines recommend the use of thiazide diuretics as first-line therapy for uncomplicated hypertension, yet diuretics are under-prescribed, and hypertension is frequently inadequately treated. This qualitative evaluation of provider attitudes follows a randomized controlled trial of a patient activation strategy in which hypertensive patients received letters and incentives to discuss thiazides with their provider. The strategy prompted high discussion rates and enhanced thiazide-prescribing rates. Our objective was to interview providers to understand the effectiveness and acceptability of the intervention from their perspective, as well as the suitability of patient activation for more widespread guideline implementation.</p> <p>Methods</p> <p>Semi-structured phone interviews were conducted with 21 primary care providers. Interviews were transcribed verbatim and reviewed by the interviewer before being analyzed for content. Interviews were coded, and relevant themes and specific responses were identified, grouped, and compared.</p> <p>Results</p> <p>Of the 21 providers interviewed, 20 (95%) had a positive opinion of the intervention, and 18 of 20 (90%) thought the strategy was suitable for wider use. In explaining their opinions of the intervention, many providers discussed a positive effect on treatment, but they more often focused on the process of patient activation itself, describing how the intervention facilitated discussions by informing patients and making them more pro-active. Regarding effectiveness, providers suggested the intervention worked like a reminder, highlighted oversights, or changed their approach to hypertension management. Many providers also explained that the intervention 'aligned' patients' objectives with theirs, or made patients more likely to accept a change in medications. Negative aspects were mentioned infrequently, but concerns about the use of financial incentives were most common. Relevant barriers to initiating thiazide treatment included a hesitancy to switch medications if the patient was at or near goal blood pressure on a different anti-hypertensive.</p> <p>Conclusions</p> <p>Patient activation was acceptable to providers as a guideline implementation strategy, with considerable value placed on the activation process itself. By 'aligning' patients' objectives with those of their providers, this process also facilitated part of the effectiveness of the intervention. Patient activation shows promise for wider use as an implementation strategy, and should be tested in other areas of evidence-based medicine.</p> <p>Trial registration</p> <p>National Clinical Trial Registry number NCT00265538</p