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BACKGROUND: There is considerable debate about the hemodynamic effects of veno-arterial extracorporeal membrane oxygenation (VA-ECMO). AIMS: To evaluate the changes in left ventricular (LV) function, volumes, and work in patients treated with VA-ECMO using invasive LV catheterization and three-dimensional echocardiographic volumes. METHODS: Patients on VA-ECMO underwent invasive hemodynamic evaluation due to concerns regarding candidacy for decannulation. Hemodynamic parameters were reported as means±standard deviations or medians (interquartile ranges) after evaluating for normality. Paired comparisons were done to evaluate hemodynamics at the baseline (highest) and lowest tolerated levels of VA-ECMO support. RESULTS: Twenty patients aged 52.3 ± 15.8 years were included. All patients received VA-ECMO for refractory cardiogenic shock (5/20 SCAI stage D, 15/20 SCAI stage E). At 3.0 (2.0, 4.0) days after VA-ECMO cannulation, the baseline LV ejection fraction was 20% (15%, 27%). The baseline and lowest VA-ECMO flows were 4.0 ± 0.6 and 1.5 ± 0.6 L/min, respectively. Compared to the lowest flow, full VA-ECMO support reduced LV end-diastolic volume [109 ± 81 versus 134 ± 93 mL, p = 0.001], LV end-diastolic pressure (14 ± 9 vs. 19 ± 9 mmHg, p < 0.001), LV stroke work (1858 ± 1413 vs. 2550 ± 1486 mL*mmHg, p = 0.002), and LV pressure-volume area (PVA) (4507 ± 1910 vs. 5193 ± 2388, p = 0.03) respectively. Mean arterial pressure was stable at the highest and lowest flows (80 ± 16 vs. 75 ± 14, respectively; p = 0.08) but arterial elastance was higher at the highest VA-ECMO flow (4.9 ± 2.2 vs lowest flow 2.7 ± 1.6; p < 0.001). CONCLUSIONS: High flow VA-ECMO support significantly reduced LV end-diastolic pressure, end-diastolic volume, stroke work, and PVA compared to minimal support. The Ea was higher and MAP was stable or minimally elevated on high flow.

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Background: Pulmonary capillary wedge pressure (PCWP) is often used as a surrogate for left-ventricular end-diastolic pressure in patients (LVEDP) who are on veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support for cardiogenic shock and cardiac arrest. However, the correlation between PCWP and LVEDP is not clear in the setting of V-A ECMO usage. We sought to evaluate this correlation in this case series. Methods: Patients were referred to our cardiac catheterization laboratory for invasive hemodynamic studies to assess their readiness for VA-ECMO decannulation. All patients underwent simultaneous left and right heart catheterization. Using standard techniques, we measured PCWP and LVEDP simultaneously. Continuous variables were reported as medians with interquartile ranges. The correlation between PCWP and LVEDP was evaluated using simple linear regression and reported as R2. Results: Four patients underwent invasive hemodynamic studies 4 (2.5, 7) days after VA-ECMO cannulation. All four patients had suffered in-hospital cardiac arrest and had been put on VA-ECMO. At the baseline level of VA-ECMO flow of 4.1 (3.8, 4.4) L/min, the median LVEDP and PCWP were 6 (4, 7.5) mmHg and 12 (6.5, 16) mmHg, respectively. At the lowest level of VA-ECMO flow of 1.9 (1.6, 2.0) L/min, the median LVEDP and PCWP was 13.5 (8.5, 16) mmHg and 15 (13, 18) mmHg, respectively. There was a poor correlation between the simultaneously measured PCWP and LVEDP (R2 = 0.03, p = 0.66). Conclusions: The PCWP may not correlate well with LVEDP in patients treated with VA-ECMO, particularly at high levels of VA-ECMO support.

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AIMS: The long-term outcomes of patients treated with extracorporeal cardiopulmonary resuscitation (ECPR) for refractory ventricular tachycardia/ventricular fibrillation (VT/VF) out-of-hospital cardiac arrest (OHCA) remain poorly defined. The purpose of this study was to describe the hospital length of stay and long-term survival of patients who were successfully rescued with ECPR after refractory VT/VF OHCA. METHODS AND RESULTS: In this retrospective cohort study, the length of index admission and long-term survival of patients treated with ECPR after OHCA at a single centre were evaluated. In a sensitivity analysis, survival of patients managed with left ventricular assist device (LVAD) implantation or heart transplantation during the same period was also evaluated. Between 1 January 2016 and 12 January 2020, 193 patients were transferred for ECPR considerations and 160 underwent peripheral veno-arterial extracorporeal membrane oxygenation cannulation. Of these, 54 (33.7%) survived the index admission. These survivors required a median 16 days of intensive care and 24 days total hospital stay. The median follow-up time of the survivors was 1216 (683, 1461) days. Of all, 79.6 and 72.2% were alive at 1 and 4 years, respectively. Most deaths within the first year occurred among the patients requiring discharge to a long-term acute care facility. Overall survival rates at 4 years were similar in the ECPR and LVAD cohorts (P = 0.30) but were significantly higher for transplant recipients (P < 0.001). CONCLUSION: This data suggest that the lengthy index hospitalization required to manage OHCA patients with ECPR is rewarded by excellent long-term clinical outcomes in an expert ECPR programme.

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In mammograms, a calcification is represented as small but brilliant white region of the digital image. Earlier detection of malignant calcifications in patients provides high expectation of surviving to this disease. Nevertheless, white regions are difficult to see by visual inspection because a mammogram is a gray-scale image of the breast. To help radiologists in detecting abnormal calcification, computer-inspection methods of mammograms have been proposed; however, it remains an open important issue. In this context, we propose a strategy for detecting calcifications in mammograms based on the analysis of the cluster prominence (cp) feature histogram. The highest frequencies of the cp histogram describe the calcifications on the mammography. Therefore, we obtain a function that models the behaviour of the cp histogram using the Vandermonde interpolation twice. The first interpolation yields a global representation, and the second models the highest frequencies of the histogram. A weak classifier is used for obtaining a final classification of the mammography, that is, with or without calcifications. Experimental results are compared with real DICOM images and their corresponding diagnosis provided by expert radiologists, showing that the cp feature is highly discriminative.

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Pseudomonas aeruginosa is an opportunistic bacterial pathogen and a primary cause of nosocomial infection in humans. The rate of antibiotic resistance in P. aeruginosa is increasing worldwide leading to an unmet need for discovery of new chemical compounds distinctly different from present antimicrobials. Protein synthesis is an essential metabolic process and a validated target for the development of new antibiotics. Initiation factor 1 from P. aeruginosa (Pa-IF1) is the smallest of the three initiation factors that act to establish the 30S initiation complex during initiation of protein biosynthesis. Here we report the characterization and solution NMR structure of Pa-IF1. Pa-IF1 consists of a five-stranded ß-sheet with an unusual extended ß-strand at the C-terminus and one short α-helix arranged in the sequential order ß1-ß2-ß3-α1-ß4-ß5. The structure adopts a typical ß-barrel fold and contains an oligomer-binding motif. A cluster of basic residues (K39, R41, K42, K64, R66, R70, and R72) located on the surface of strands ß4 and ß5 near the short α-helix may compose the binding interface with the 30S subunit.

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Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen and a primary cause of infection in humans. P. aeruginosa can acquire resistance against multiple groups of antimicrobial agents, including ß-lactams, aminoglycosides and fluoroquinolones, and multidrug resistance is increasing in this organism which makes treatment of the infections difficult and expensive. This has led to the unmet need for discovery of new compounds distinctly different from present antimicrobials. Protein synthesis is an essential metabolic process and a validated target for the development of new antibiotics. Translation initiation factor 1 from P. aeruginosa (Pa-IF1) is the smallest of the three initiation factors that acts to establish the 30S initiation complex to initiate translation during protein biosynthesis, and its structure is unknown. Here we report the (1)H, (13)C and (15)N chemical shift assignments of Pa-IF1 as the basis for NMR structure determination and interaction studies. Secondary structure analyses deduced from the NMR chemical shift data have identified five ß-strands with an unusually extended ß-strand at the C-terminal end of the protein and one short α-helix arranged in the sequential order ß1-ß2-ß3-α1-ß4-ß5. This is further supported by (15)N-{(1)H} hetero NOEs. These secondary structure elements suggest the Pa-IF1 adopts the typical ß-barrel structure and is composed of an oligomer-binding motif.

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To determine the impact of multiple micromanipulation procedures for preimplantation genetic diagnosis (PGD) on embryo development, a retrospective analysis was performed of 9,925 embryos (862 PGD cycles), which were compared with 28,126 nonbiopsied embryos (2,751 consecutive intracytoplasmic sperm injection [ICSI] cycles) from the same time period. Because fertilization rates, the proportion of embryos with > or = 6 cells on day 3, and blastocyst rates were similar in the PGD and control groups, we conclude that multiple micromanipulations on oocytes and embryos can be performed safely for PGD.

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The World Health Organization (WHO) estimates that 50-80 x 10(6) couples in the world are infertile, i.e. 7-15% of all couples of reproductive age (15-45 years old). The term infertility refers to couples who have been unable to conceive children for at least 1 year of regular unprotected intercourse. Although the frequency and origin of infertility varies, approximately 40-60% of the aetiology of infertility in the population studied is due to female causes. The introduction of assisted reproduction techniques, which offer couples the best opportunities for pregnancy, has opened a vast field of knowledge in reproductive biology. The medical history must be taken meticulously, with enough time to obtain the largest possible amount of relevant information. It is recommended that both partners be included in the initial work-up. In recent decades, technological progress has been favoured with the development of a great variety of diagnostic tests. Moreover, a very valuable tool helping to solve this problem has gained strength and is available to everybody - so-called 'evidence-based medicine'. There are three categories in infertility diagnostic tests. The first category includes tests showing a well-established correlation with pregnancy, e.g. semen analysis, tubal patency with hysterosalpingography or laparoscopy, and ovulation detection. The second category includes patients whose results are not consistently related to pregnancy. Here, these tests include sperm penetration assay in the zona-free hamster oocyte, post-coital tests, sperm penetration into cervical mucus, and tests to detect anti-sperm antibodies. The third group includes patients whose tests are not correlated with pregnancy. The relevant tests include endometrial biopsy, the presence of varicocele, and Chlamydia detection tests. Tests for infertility are often expensive. Since these patients are usually anxious and eager and will do almost anything to have a child, care must be taken to avoid exploitation of their hopes with unnecessary procedures. This text now reviews and updates the procedures used to investigate infertility.

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