Simulation of Liquid Flow Permeability for Dendritic Structures during Solidification Process

status: Published onlin

False-positive troponin elevation due to an immunoglobulin-G-cardiac troponin T complex: a case report.

Background: Troponin is a crucial biomarker for the diagnosis of an acute coronary syndrome (ACS). It rises in response to myocardial injury from significant acute myocardial ischaemia caused by obstructive coronary artery disease ['classical' myocardial infarction (MI)]. However, raised levels have also been noted in conditions not recognized as classical ACS. This may include MI with non-obstructed coronary arteries such as takotsubo cardiomyopathy and other acute or chronic conditions such as pulmonary embolus or chronic kidney disease. This is commonly labelled as a 'falsely elevated' troponin although there is some myocardial strain to explain the rise, such as an increase in cardiac oxygen demand. True 'falsely elevated' troponin, characterized by a persistent elevation in the absence of cardiac injury does occur and thought to be secondary to an immunoglobulin-troponin complex (macrotroponin). Case summary: A 53-year-old gentleman with a background of diabetes, hypertension, hypercholesterolaemia, and hepatitis B was admitted with chest pain and persistently elevated cardiac troponin T (cTnT) levels. Investigations revealed unobstructed coronary arteries and a structurally normal, well-functioning heart. Subsequent biochemical analysis found the persistently elevated cTnT secondary to macrotroponin T. Discussion: Macrotroponin, an immunoglobulin-troponin bound complex should be considered as a differential diagnosis when the biochemistry is not reflective of the clinical picture. Early recognition requires effective collaboration with the biochemistry laboratory for accurate diagnosis

Outcomes of Midurethral Slings in Women with Concomitant Preoperative Severe Lower Urinary Tract Voiding Symptoms

BACKGROUND: Women with stress urinary incontinence and concomitant obstructive (voiding) lower urinary tract symptoms (LUTS) represent a challenging patient population. Furthermore, their diagnosis and management remain incompletely studied and controversial. We evaluated the outcomes of midurethral sling procedures in women with severe obstructive LUTS. METHODS: We performed a post hoc analysis of women who were part of an institutional review board-approved study of midurethral sling surgery. Preoperatively and at 4-6 weeks postoperatively, patients completed the American Urological Association Symptom Score (AUASS) questionnaire. A postvoid residual urine test was obtained preoperatively, at the time of the voiding trial, and 4-6 weeks postoperatively. Three groups of patients with severe LUTS were then defined: Group A (AUASS \u3e/=20), Group B (voiding subscale \u3e/=12), and Group C (urodynamic obstruction). Patients could be included in more than one group. AUASS was again obtained at a medium-term follow-up of 31.6 months. RESULTS: Of 106 women completing follow-up, 30, 23, and 11 subjects met the criteria for groups A, B, and C, respectively. All had statistically significant improvements in storage and voiding subscales, as well as their stress urinary incontinence. No subject presented with retention or voiding dysfunction at follow-up. These improvements continued at medium-term follow-up with the exception of Group C that failed to demonstrate persistence of statistical improvement in AUASS subscales. CONCLUSION: Patients with stress urinary incontinence and severe voiding LUTS can be treated safely with midurethral sling procedures. In both the short and medium term, these symptoms improve dramatically in the majority of patients

Examination of the Behavior of Gravity Quay Wall against Liquefaction under the Effect of Wall Width and Soil Improvement

Deformation of quay walls is one of the main sources of damage to port facility while liquefaction of backfill and base soil of the wall are the main reasons for failures of quay walls. During earthquakes, the most susceptible materials for liquefaction in seashore regions are loose saturated sand. In this study, effects of enhancing the wall width and the soil improvement on the behavior of gravity quay walls are examined in order to obtain the optimum improved region. The FLAC 2D software was used for analyzing and modeling progressed models of soil and loading under difference conditions. Also, the behavior of liquefiable soil is simulated by the use of “Finn” constitutive model in the analysis models. The “Finn” constitutive model is especially created to determine liquefaction phenomena and excess pore pressure generation

Extraction and identification of steroids in two species marine algae, Sargassum oligocystum and Nizamudiinia zanardinii in Persian Gulf and Oman Sea

Sargassum oligocystum and Nizamudiinia zanardinii are the most abundant algae distributed in the north of Persian Gulf and Oman Sea. In this study after sampling and preparation of S. oligocystum by Chroform-Etanol (3-1) solvent and N. zanardinii by methanol has been extract. Separation and purification of the compounds was carried out using thin layer, general and inverse column chromatography, Cephadex and high-performance liquid chromatography (HPLC ). Structural elucidation of the constituents was based on the data obtained from HNMR, 13C-NMR, HSQC, HMBC, DEPT and Cephadex LH-20. The steroids compounds separated from above algae were identified as 22-dehydrocholesterol (1) cholesterol (2) fucosterol (3) 29-hydroperoxystigmasta-5,24(28)-dien-3β-ol (4) 24-hydroperoxy-24- vinylcholesterol (5) a mixture of 24(S)-hydroxy-24-vinylcholesterol (6) and 24(R)-hydroxy-24- vinylcholesterol (7) and ostreasterol (8) based on their spectral data and from comparison with those previously reported in the literature

A cell-free SDKP-conjugated self-assembling peptide hydrogel sufficient for improvement of myocardial infarction

Biomaterials in conjunction with stem cell therapy have recently attracted attention as a new therapeutic approach for myocardial infarction (MI), with the aim to solve the delivery challenges that exist with transplanted cells. Self-assembling peptide (SAP) hydrogels comprise a promising class of synthetic biomaterials with cardiac-compatible properties such as mild gelation, injectability, rehealing ability, and potential for sequence modification. Herein, we developed an SAP hydrogel composed of a self-assembling gel-forming core sequence (RADA) modified with SDKP motif with pro-angiogenic and anti-fibrotic activity to be used as a cardioprotective scaffold. The RADA-SDKP hydrogel was intramyocardially injected into the infarct border zone of a rat model of MI induced by left anterior descending artery (LAD) ligation as a cell-free or a cell-delivering scaffold for bone marrow mesenchymal stem cells (BM-MSCs). The left ventricular ejection fraction (LVEF) was markedly improved after transplantation of either free hydrogel or cell-laden hydrogel. This cardiac functional repair coincided very well with substantially lower fibrotic tissue formation, expanded microvasculature, and lower inflammatory response in the infarct area. Interestingly, BM-MSCs alone or in combination with hydrogel could not surpass the cardiac repair effects of the SDKP-modified SAP hydrogel. Taken together, we suggest that the RADA-SDKP hydrogel can be a promising cell-free construct that has the capability for functional restoration in the instances of acute myocardial infarction (AMI) that might minimize the safety concerns of cardiac cell therapy and facilitate clinical extrapolation. © 2020 by the authors. Licensee MDPI, Basel, Switzerland

Patient-specific Computer Simulation: An Emerging Technology for Guiding the Transcatheter Treatment of Patients with Bicuspid Aortic Valve.

Transcatheter aortic valve implantation (TAVI) is increasingly being used to treat younger, lower-risk patients, many of whom have bicuspid aortic valve (BAV). As TAVI begins to enter these younger patient cohorts, it is critical that clinical outcomes from TAVI in BAV are matched to those achieved by surgery. Therefore, the identification of patients who, on an anatomical basis, may not be suitable for TAVI, would be desirable. Furthermore, clinical outcomes of TAVI in BAV might be improved through improved transcatheter heart valve sizing and positioning. One potential solution to these challenges is patient-specific computer simulation. This review presents the methodology and clinical evidence surrounding patient-specific computer simulation of TAVI in BAV

Clinical significance of intraventricular gradient during effort in an adolescent karate player

The authors report the case of a 16-year-old boy who practices karate, who underwent medical evaluation because of atypical chest discomfort, related to strenuous effort. The ECG and echocardiogram findings were normal. The young boy did a treadmill stress test which was positive for myocardial ischemia. Late during the investigation, he underwent treadmill stress echocardiography, during which he developed intraventricular gradient of over 130 mmHg with end-systolic peak and systolic anterior movement (SAM) of the mitral valve. These echocardiographic findings were not present at rest and disappeared shortly after termination of exercise. The authors discuss the significance of this event. This leads us to advise withdrawal from participation in competitive sport according to the recomendations of the European Society of Cardiology. A possible role of exercise stress echo for intraventricular pressure gradient assessment in symptomatic athletes with structurally normal hearts is suggested

Prior Coronary Artery Bypass Graft Surgery and Outcome After Percutaneous Coronary Intervention: An Observational Study From the Pan-London Percutaneous Coronary Intervention Registry.

Background Limited information exists regarding procedural success and clinical outcomes in patients with previous coronary artery bypass grafting (CABG) undergoing percutaneous coronary intervention (PCI). We sought to compare outcomes in patients undergoing PCI with or without CABG. Methods and Results This was an observational cohort study of 123 780 consecutive PCI procedures from the Pan-London (UK) PCI registry from 2005 to 2015. The primary end point was all-cause mortality at a median follow-up of 3.0 years (interquartile range, 1.2-4.6 years). A total of 12 641(10.2%) patients had a history of previous CABG, of whom 29.3% (n=3703) underwent PCI to native vessels and 70.7% (n=8938) to bypass grafts. There were significant differences in the demographic, clinical, and procedural characteristics of these groups. The risk of mortality during follow-up was significantly higher in patients with prior CABG (23.2%; P=0.0005) compared with patients with no prior CABG (12.1%) and was seen for patients who underwent either native vessel (20.1%) or bypass graft PCI (24.2%; P<0.0001). However, after adjustment for baseline characteristics, there was no significant difference in outcomes seen between the groups when PCI was performed in native vessels in patients with previous CABG (hazard ratio [HR],1.02; 95%CI, 0.77-1.34; P=0.89), but a significantly higher mortality was seen among patients with PCI to bypass grafts (HR,1.33; 95% CI, 1.03-1.71; P=0.026). This was seen after multivariate adjustment and propensity matching. Conclusions Patients with prior CABG were older with greater comorbidities and more complex procedural characteristics, but after adjustment for these differences, the clinical outcomes were similar to the patients undergoing PCI without prior CABG. In these patients, native-vessel PCI was associated with better outcomes compared with the treatment of vein grafts