High-Performance Reversed-Phase Flash Chromatography Purification of Peptides and Chemically Modified Insulins.

Preparative reversed-phase HPLC is the established method for the purification of peptides, but has significant limitations. We systematically investigated the use of high-performance reversed-phase flash chromatography (HPFC) to rapidly purify laboratory-scale quantities of crude, synthetic peptides and chemically modified insulins. We demonstrated these methods for a diverse set of peptides, including short, medium, and long peptides. Depending on the purity profile of the peptide, HPFC can be used either as the sole purification method, or as a pre-purification method prior to final HPLC purification. Furthermore, HPFC is suitable for the purification of peptides that are not fully in solution. We provide guidelines for the HPFC of synthetic peptides and small proteins, including the choice of columns, eluents, and gradients. We believe that HPFC is a valuable alternative to HPLC purification of peptides and small proteins.

Role of Cardiac Magnetic Resonance Imaging in the Management and Treatment of Ventricular Tachycardia in Patients With Structural Heart Disease.

Treatment for ventricular tachycardia (VT) generally includes 1 or more of the following options: antiarrhythmic therapy, an implantable cardioverter-defibrillator and/or catheter ablation. Catheter ablation is performed with an electroanatomic mapping system to define the heart's 3D anatomy, as well as regions of scar. Radiofrequency energy is then applied to areas of abnormal substrate within which are located channels critical to the VT circuit. Cardiac magnetic resonance (CMR) imaging is a non-invasive modality that provides high-resolution images of cardiac structure and function. CMR has become a very useful tool for sudden cardiac death risk stratification and to facilitate successful radiofrequency ablation of VT in patients with abnormal cardiac substrate. The role of CMR in the management and treatment of VT in patients with structural heart disease is reviewed.

Real-time particle size analysis using focused beam reflectance measurement as a process analytical technology tool for a continuous granulation-drying-milling process.

Focused beam reflectance measurement (FBRM) was used as a process analytical technology tool to perform inline real-time particle size analysis of a proprietary granulation manufactured using a continuous twin-screw granulation-drying-milling process. A significant relationship between D20, D50, and D80 length-weighted chord length and sieve particle size was observed with a p value of <0.0001 and R(2) of 0.886. A central composite response surface statistical design was used to evaluate the effect of granulator screw speed and Comil® impeller speed on the length-weighted chord length distribution (CLD) and particle size distribution (PSD) determined by FBRM and nested sieve analysis, respectively. The effect of granulator speed and mill speed on bulk density, tapped density, Compressibility Index, and Flowability Index were also investigated. An inline FBRM probe placed below the Comil-generated chord lengths and CLD data at designated times. The collection of the milled samples for sieve analysis and PSD evaluation were coordinated with the timing of the FBRM determinations. Both FBRM and sieve analysis resulted in similar bimodal distributions for all ten manufactured batches studied. Within the experimental space studied, the granulator screw speed (650-850 rpm) and Comil® impeller speed (1,000-2,000 rpm) did not have a significant effect on CLD, PSD, bulk density, tapped density, Compressibility Index, and Flowability Index (p value > 0.05).

Pandemic within a pandemic! Policy Implications of community-based Interventions to mitigate violence against women during COVID-19 in Urban Slums of Lucknow, India.

Background: The COVID-19 pandemic has brought an unprecedented adverse impact on women's health. Evidence from the literature suggests that violence against women has increased multifold. Gender-based violence in urban slums has worsened due to a lack of water and sanitation services, overcrowding, deteriorating conditions and a lack of institutional frameworks to address gender inequities. Methods: The SAMBHAV (Synchronized Action for Marginalized to Improve Behaviors and Vulnerabilities) initiative was launched between June 2020 to December 2020 by collaborating with the Uttar Pradesh state government, UNICEF and UNDP. The program intended to reach 6000 families in 30 UPS (Urban Poor settlements) of 13 city wards. These 30 UPS were divided into 5 clusters. The survey was conducted in 760 households, 397 taken from randomly selected 15 interventions and 363 households from 15 control UPS. This paper utilized data from a baseline assessment of gender and decision-making from a household survey conducted in the selected UPS during July 03-15, 2020. A sample size of 360 completed interviews was calculated for intervention and control areas to measure changes attributable to the SAMBHAV intervention in the behaviours and service utilization (pre- and post-intervention). Results: The data analysis showed a significant difference (p-value < 0.001) between respondents regarding women's freedom to move alone in the control and intervention area. It also reflected a significant difference between control and intervention areas as the respondents in the intervention area chose to work for the cause of gender-based violence. Conclusion: The SAMBHAV initiative brought an intersectional lens to gender issues. The community volunteers were trained to approach issues based on gender-based violence with the local public, and various conferences and meetings were organized to sensitize the community. The initiative's overall impact was that it built momentum around the issue of applying the concept of intersectionality for gender issues and building resilience in the community. There is still a need to bring multi-layered and more aggressive approaches to reduce the prevalence of gender-based violence in the community.

Wellens syndrome: a life-saving diagnosis.

The diagnosis of acute coronary syndrome relies on clinical history, electrocardiographic (ECG) changes, and cardiac biomarkers; but within the spectrum of acute coronary syndrome, there exist subtle presentations that cannot afford to be overlooked. Wellens syndrome is one such example, in which a patient can present with both ECG changes that are not classic for myocardial ischemia and negative cardiac biomarkers. The characteristic ECG findings associated with Wellens syndrome consist of deep, symmetric T-wave inversions in the anterior precordial leads. However, Wellens syndrome can also present as biphasic T-wave inversions in those same ECG leads. The associated critical stenosis of the proximal left anterior descending artery carries an immediately life-threatening prognosis if not recognized promptly (Am Heart J. 1982;103[4 Pt 2]:730-736). We describe a case of a less common manifestation of Wellens syndrome (type 1) followed by a discussion of its implications and management.

Inline real-time near-infrared granule moisture measurements of a continuous granulation-drying-milling process.

The purpose of this research was to use inline real-time near-infrared (NIR) to measure the moisture content of granules manufactured using a commercial production scale continuous twin-screw granulator fluid-bed dryer milling process. A central composite response surface statistical design was used to study the effect of inlet air temperature and dew point on granule moisture content. The NIR moisture content was compared to Karl Fischer (KF) and loss on drying (LOD) moisture determinations. Using multivariate analysis, the data showed a statistically significant correlation between the conventional methods and NIR. The R(2) values for predicted moisture content by NIR versus KF and predicted moisture values by NIR versus LOD were 0.94 (p < 0.00001) and 0.85 (p < 0.0002), respectively. The adjusted R(2) for KF versus LOD correlation was 0.85 (p < 0.0001). Analysis of the response surface design data showed that inlet air temperature over a range of 35-55°C had a significant linear impact on granule moisture content as measured by predicted NIR (adjusted R(2) = 0.84, p < 0.02), KF (adjusted R(2) = 0.91, p < 0.0001), and LOD (adjusted R(2) = 0.85, p < 0.0006). The inlet air dew point range of 10-20°C did not have a significant impact on any of the moisture measurements.

Aggregate Filamentous Growth Responses in Yeast.

Many fungal species, including pathogens, undergo a morphogenetic response called filamentous growth, where cells differentiate into a specialized cell type to promote nutrient foraging and surface colonization. Despite the fact that filamentous growth is required for virulence in some plant and animal pathogens, certain aspects of this behavior remain poorly understood. By examining filamentous growth in the budding yeast Saccharomyces cerevisiae and the opportunistic pathogen Candida albicans, we identify responses where cells undergo filamentous growth in groups of cells or aggregates. In S. cerevisiae, aggregate invasive growth was regulated by signaling pathways that control normal filamentous growth. These pathways promoted aggregation in part by fostering aspects of microbial cooperation. For example, aggregate invasive growth required cellular contacts mediated by the flocculin Flo11p, which was produced at higher levels in aggregates than cells undergoing regular invasive growth. Aggregate invasive growth was also stimulated by secreted enzymes, like invertase, which produce metabolites that are shared among cells. Aggregate invasive growth was also induced by alcohols that promote density-dependent filamentous growth in yeast. Aggregate invasive growth also required highly polarized cell morphologies, which may affect the packing or organization of cells. A directed selection experiment for aggregating phenotypes uncovered roles for the fMAPK and RAS pathways, which indicates that these pathways play a general role in regulating aggregate-based responses in yeast. Our study extends the range of responses controlled by filamentation regulatory pathways and has implications in understanding aspects of fungal biology that may be relevant to fungal pathogenesis.IMPORTANCE Filamentous growth is a fungal morphogenetic response that is critical for virulence in some fungal species. Many aspects of filamentous growth remain poorly understood. We have identified an aspect of filamentous growth in the budding yeast Saccharomyces cerevisiae and the human pathogen Candida albicans where cells behave collectively to invade surfaces in aggregates. These responses may reflect an extension of normal filamentous growth, as they share the same signaling pathways and effector processes. Aggregate responses may involve cooperation among individual cells, because aggregation was stimulated by cell adhesion molecules, secreted enzymes, and diffusible molecules that promote quorum sensing. Our study may provide insights into the genetic basis of collective cellular responses in fungi. The study may have ramifications in fungal pathogenesis, in situations where collective responses occur to promote virulence.

Spontaneous separation of charged grains.

In 1867, Lord Kelvin described an experiment in which two streams of water droplets were connected so that each stream amplified the charge on the second stream [W. Thomson, Proc. R. Soc. London 16, 67 (1867)]. We present here a complementary effect in flowing grains that spontaneously separates similar and well-mixed grains into two charged streams of demixed grains. This effect has important consequences for industrial and natural processes.

Influence of shear intensity and total shear on properties of blends and tablets of lactose and cellulose lubricated with magnesium stearate.

A new technique to quantify the effects of shear intensity and total shear on the homogeneity, flowability and bulk density of a lubricated free-flowing pharmaceutical blend and on properties of resulting tablets is presented. A modified Couette cylindrical cell with uniformly spaced pins is used to create a uniform shear environment. The range of lubricant concentrations explored is 0-2% (on a mass basis). Sheared blends are used to produce tablets in the Presster (a simulator of an actual tablet press), allowing us to correlate the shear history of the blend (shear intensity and total shear) with the crushing hardness of tablets. The results show that the larger the total shear, the more homogeneous the blend. Bulk density increases with total shear until reaching a distinctive plateau. Results also indicate that high total shear affects the blend flow properties. For tablets, crushing hardness decreases as concentration of lubricant and total shear increase. Interestingly, and unexpectedly, under constant total shear, shear intensity affects the crushing hardness of tablets only slightly.

Effect of moisture and magnesium stearate concentration on flow properties of cohesive granular materials.

In this article the gravitational displacement rheometer (GDR) is used to characterize the effects of formulation composition and environmental conditions (moisture) on flow properties of cohesive pharmaceutical powders under unconfined conditions. The amount of moisture in the sample often has important effects on the physical and chemical properties of pharmaceutical solids. Properties such as flow, compaction, disintegration, dissolution, hardness and chemical stability are all influenced by moisture. In the case of lactose, as moisture content increases in the powder bed, the flowability becomes poorer as the moisture condenses on the surface and increases cohesion. The celluloses show opposite effect as compared to lactose. Here, as moisture content increases, the flow properties improve dramatically. The GDR also captures the effect of lubricant concentration on the cohesion of powders. The presence of lubricant does not play any significant impact for free flowing powders, but as powder cohesion increases, the lubricants allow for improved flowability of powders. The GDR was also used for a case study of real drug formulation. The methodology was able to evaluate the impact of humidity and lubricant concentration on the flow properties of the formulation.

Elevated S100A12 and sRAGE are associated with increased length of hospitalization after non-urgent coronary artery bypass grafting surgery.

UNLABELLED: Study's purpose: Plasma levels of soluble receptor for advanced glycation endproducts (sRAGE) and S100A12 are increased in young children after cardiac surgery and correlate with the time spent on cardiopulmonary bypass (CPB). This study was performed to investigate whether plasma levels of sRAGE and S100A12 are affected by the use of CPB. Levels of S100A12 and sRAGE, along with of interleukin-6, tumor necrosis factor-α, myeloperoxidase, and C-reactive protein were measured in 25 adults undergoing non-urgent coronary artery bypass grafting with and without the use of CPB. Significant finding: Plasma levels of S100A12, sRAGE, IL-6, TNF-α and MPO 4h after cardiac surgery were elevated compared to baseline; this increase was equally observed in patients undergoing traditional coronary artery bypass grafting on cardiopulmonary bypass (n = 16), and in patients undergoing robot-assisted coronary artery bypass grafting off pump (OPCAB, n = 9). Patients with prolonged hospitalization of 7 days or longer had significantly higher S100A12 and sRAGE 4 hours post surgery compared to patients hospitalized ≤ 6 days. CONCLUSION: Increased sRAGE and S100A12 after cardiac surgery is associated with prolonged length of hospitalization in patients after coronary artery bypass grafting; however, we did not observe an intrinsic effect of cardiopulmonary bypass on S100A12 or sRAGE plasma levels in our small pilot study. Further studies are required to confirm the value of sRAGE and S100A12 in predicting postoperative complications after cardiac surgery in a larger study.

Percutaneous transcatheter aortic valve closure successfully treats left ventricular assist device-associated aortic insufficiency and improves cardiac hemodynamics.

OBJECTIVES: This study sought to assess the effectiveness of a novel percutaneous method to treat left ventricular assist device (LVAD)-associated severe aortic insufficiency (AI) in a series of patients determined to be poor reoperative candidates. BACKGROUND: The increased use of continuous-flow LVAD in advanced heart failure has led to marked changes in the management of patients with this condition. However, secondary AI can become a significant complication. METHODS: Five patients with continuous-flow LVAD and severe post-LVAD AI underwent percutaneous transcatheter aortic valve closure from September to October 2011 at a single quaternary care academic medical center. All patients had LVAD implanted as destination therapy. LVAD parameters, hemodynamics, and echocardiographic measurements were obtained before and after aortic valve closure. RESULTS: All patients underwent successful closure with the Amplatzer cribriform device (AGA Medical, Plymouth, Minnesota) via a percutaneous transcatheter femoral approach with a significant reduction of AI from severe to trivial. Cardiac hemodynamics improved, and the pulmonary capillary wedge pressure was reduced in all patients. There was no change in mitral or tricuspid regurgitation, LVAD power, or pulsatility index. CONCLUSIONS: Percutaneous transcatheter closure of the aortic valve effectively treats LVAD-associated AI and reduces pulmonary capillary wedge pressure. This procedure should be considered to treat LVAD-associated AI in patients who are poor candidates for repeat operation. Further data are needed to assess long-term results.

Takotsubo cardiomyopathy after treatment of pulmonary arterial hypertension.

Pulmonary arterial hypertension is a fatal disease. Intravenous prostanoids are often utilized for long-term management of patients. The therapy requires a significant commitment and change in lifestyle for both the patient and family. Takotsubo cardiomyopathy, transient apical ballooning syndrome, has been reported in association with emotional and physical stress. This case report describes a patient with pulmonary arterial hypertension who developed Takotsubo cardiomyopathy after treatment initiation with intravenous treprostinil. Over time, the syndrome resolved and the patient had return of normal left ventricular function. Takotsubo cardiomyopathy should be recognized as a potential, rare complication of therapy initiation due to the severity of the illness and the emotional stress of the disease.

Dramatic improvement in hypoxemic respiratory failure after patent foramen ovale closure in a patient with obesity hypoventilation syndrome.

We report a case of a patient with pulmonary hypertension who presented with acute hypoxemic respiratory failure. The patient had continued refractory hypoxemia despite a prolonged ICU admission that included ventilatory support, and empiric therapy for pulmonary embolism and pneumonia. Transthoracic echocardiography (TTE) revealed a patent foramen ovale (PFO), which after percutaneous closure resulted in profound improvement in hypoxemia and clinical status.

Medtronic Sprint Fidelis lead recall: determining the initial 5-year management cost to Medicare.

BACKGROUND: The Medtronic Sprint Fidelis defibrillator lead has a high failure rate and was recalled in October 2007. OBJECTIVE: The purpose of this study was to determine the incremental cost of the management of this lead to Medicare. METHODS: Real hospital cost data in U.S. dollars were collected on 32 patients with a Medtronic Sprint Fidelis lead who underwent lead revision. Of these patients, 15 were excluded because they had insurance coverage other than that provided by the Centers for Medicare & Medicaid Services. Seventeen patients with Medicare or Medicaid coverage underwent lead revision either electively (n = 6) or after being hospitalized for multiple shocks caused by a lead fracture (n = 11). Eighty-eight percent of the patients underwent extraction of the Fidelis lead at the time of lead revision. A decision model was made that outlines the potential management of the lead recall over time. The existing literature and Medtronic data were reviewed for parameters included in the decision model. The model assumed that 175,000 patients were alive with an implanted Fidelis lead at the time of the recall and that the annual failure rate will be 1.8% over the first 5 years. It was also assumed that 1% of patients without a lead fracture would also undergo elective lead revision each year and that the proportion of patients who would have the Fidelis lead extracted rather than abandoned would be 20:80. Estimates with ranges were used for parameters for which no data are available. The industry standard rate of lead failure was estimated based on the Sprint Quattro model 6947 lead, and this was subtracted from the estimated rates for the Sprint Fidelis lead such that the incremental cost of the lead failure could be estimated. RESULTS: The cost of lead revision trended higher when the Fidelis lead was extracted rather than abandoned ($45,077 ± $11,693 vs $33,802 ± $33, P = .20). In 5 years, the estimated cost impact of the Medtronic Sprint Fidelis lead recall to Medicare will be $287,000,000 (range $176,000,000-$1,186,000,000, October 2007 USD). CONCLUSION: The cost impact of managing a defibrillator lead with a high failure rate to Medicare will be substantial.

Usefulness of red cell distribution width as a prognostic marker in pulmonary hypertension.

Red blood cell distribution width (RDW), a widely available biomarker, independently predicts adverse outcomes in left-sided heart failure. The relation between RDW and death in pulmonary hypertension (PH) is unknown. In a prospective study of 162 consecutive patients with PH, RDW was recorded during initial diagnostic right-sided cardiac catheterization, and patients were followed for 2.1 +/- 0.8 years to determine vital status. Demographic, clinical, laboratory, and hemodynamic variables were compared by tertile of RDW. Cox proportional-hazards models were used to determine whether RDW was independently associated with death, and the prognostic utility of RDW was compared to that of other laboratory predictors, including N-terminal-pro-B-type natriuretic peptide (NT-pro-BNP). Of the 162 study patients, 78% were women, and 62% had pulmonary arterial hypertension. The mean age was 53 +/- 15 years, and most patients had severe PH (mean pulmonary artery pressure 48 +/- 13 mm Hg). The highest tertile of RDW predicted death (univariate hazard ratio 4.86, 95% confidence interval 1.37 to 17.29, p = 0.015; multivariate hazard ratio 2.4, 95% confidence interval 1.02 to 5.84, p = 0.045, after adjusting for age, gender, diabetes mellitus, connective tissue disease, diuretic use, phosphodiesterase inhibitor use, hemoglobin, mean corpuscular volume, and blood urea nitrogen [BUN]). Of the laboratory data, only RDW, BUN, and NT-pro-BNP were associated with death on univariate analysis. When RDW, BUN, and NT-pro-BNP were entered into a multivariate model, only RDW was still associated with death (p = 0.037 for RDW, p = 0.18 for BUN, and p = 0.39 for NT-pro-BNP). Adding NT-pro-BNP to RDW did not improve the prediction of mortality. In conclusion, RDW is independently associated with death in patients with PH and performs better as a prognostic indicator than NT-pro-BNP.