Clinician and patient attitudes toward use of organs from hepatitis C viremic donors and their impact on acceptance: A contemporary review.

BACKGROUND: The use of Hepatitis C (HCV) NAT positive allografts remains unusual and is clustered at few centers. We conducted a contemporary literature review to assess whether patient and clinician attitudes toward viremic organs impact acceptance. METHODS: Databases including PubMed, MEDLINE, and SCOPUS databases were reviewed to identify studies focused on evaluating patient and provider perceptions of HCV NAT positive organ use within the DAA era (January 2015-April 2021). Search included MeSH terms related to Hepatitis C, transplantation, and patient and clinician attitudes. Two investigators extracted study characteristics including information on willingness to accept viremic organs, HCV-specific outcomes knowledge, HCV-specific concerns, and factors that contributed to acceptance or non-acceptance. RESULTS: Eight studies met all inclusion criteria. These included three pretransplant patient-directed studies, two post-transplant patient-directed studies, one pre- and post-transplant patient-directed study, and two clinician-directed studies. Common themes identified were concerns regarding HCV cure rates, viremic organ quality, DAA cost, stigma, and the possibility of HCV transmission to household members. The perception of decreased waitlist time was associated with viremic organ acceptance. Physician trust played a mixed role in acceptance patterns. CONCLUSIONS: Knowledge of high cure rates, shorter waitlist times, and higher organ quality appear to have the highest impact on organ acceptance.

Erratum: Quantum Criticality in Quasi-Two-Dimensional Itinerant Antiferromagnets [Phys. Rev. Lett. 115, 186405 (2015)].

This corrects the article DOI: 10.1103/PhysRevLett.115.186405.

The relationship of systemic markers of renal function and vascular function with retinal blood vessel responses.

PURPOSE: To test the hypothesis of a significant relationship between systemic markers of renal and vascular function (processes linked to cardiovascular disease and its development) and retinal microvascular function in diabetes and/or cardiovascular disease. METHODS: Ocular microcirculatory function was measured in 116 patients with diabetes and/or cardiovascular disease using static and continuous retinal vessel responses to three cycles of flickering light. Endothelial function was evaluated by von Willebrand factor (vWf), endothelial microparticles and soluble E selectin, renal function by serum creatinine, creatinine clearance and estimated glomerular filtration rate (eGFR). HbA1c was used as a control index. RESULTS: Central retinal vein equivalence and venous maximum dilation to flicker were linked to HbA1c (both p < 0.05). Arterial reaction time was linked to serum creatinine (p = 0.036) and eGFR (p = 0.039); venous reaction time was linked to creatinine clearance (p = 0.018). Creatinine clearance and eGFR were linked to arterial maximum dilatation (p < 0.001 and p = 0.003, respectively) and the dilatation amplitude (p = 0.038 and p = 0.048, respectively) responses in the third flicker cycle. Of venous responses to the first flicker cycle, HbA1c was linked to the maximum dilation response (p = 0.004) and dilatation amplitude (p = 0.017), vWf was linked to the maximum constriction response (p = 0.016), and creatinine clearance to the baseline diameter fluctuation (p = 0.029). In the second flicker cycle, dilatation amplitude was linked to serum creatinine (p = 0.022). CONCLUSIONS: Several retinal blood vessel responses to flickering light are linked to glycaemia and renal function, but only one index is linked to endothelial function. Renal function must be considered when interpreting retinal vessel responses.

Quantum Criticality in Quasi-Two-Dimensional Itinerant Antiferromagnets.

Quasi-two-dimensional itinerant fermions in the antiferromagnetic (AFM) quantum-critical region of their phase diagram, such as in the Fe-based superconductors or in some of the heavy-fermion compounds, exhibit a resistivity varying linearly with temperature and a contribution to specific heat or thermopower proportional to TlnT. It is shown, here, that a generic model of itinerant anti-ferromagnet can be canonically transformed so that its critical fluctuations around the AFM-vector Q can be obtained from the fluctuations in the long wavelength limit of a dissipative quantum XY model. The fluctuations of the dissipative quantum XY model in 2D have been evaluated recently, and in a large regime of parameters, they are determined, not by renormalized spin fluctuations, but by topological excitations. In this regime, the fluctuations are separable in their spatial and temporal dependence and have a spatial correlation length which is proportional to the logarithm of the temporal correlation length, i.e., for some purposes, the effective dynamic exponent z=∞. The time dependence gives ω/T scaling at criticality. The observed resistivity and entropy then follow. Several predictions to test the theory are also given.

Safety and efficacy of abciximab in older adults undergoing percutaneous coronary intervention.

BACKGROUND: As a result of increased cost and bleeding concerns, older patients receive abciximab during percutaneous coronary intervention (PCI) less often than younger patients. OBJECTIVE: The aim of this was to evaluate the safety and efficacy of abciximab in older adults undergoing PCI. DESIGN: Retrospective, observational single centre cohort study. METHODS: The British Cardiovascular Intervention Society (BCIS) database was used to establish the impact of abciximab in people with advanced age (≥ 75 years) on in-hospital bleeding and ischaemic events and all-cause mortality in 5727 consecutive patients undergoing PCI between January 2008 and June 2014. RESULTS: Older patients represented 23% of the study population (n = 1298). Abciximab was used in 198 (15%) older patients and 970 (22%) younger patients (p < 0.001). Unadjusted bleeding and mortality rates were 1.2% and 5.6%, respectively, vs. 0.4% and 1.7% in younger patients (p = 0.001 and p < 0.001 respectively). On multivariate analysis older subjects were at higher risk of bleeding [odds ratio (OR) 2.76, 95% confidence interval (CI) 1.26-6.04, p = 0.011] and had higher in-hospital mortality (OR 2.36, 95% CI 1.48-3.74, p < 0.001). The use of abciximab in older patients was not significantly associated with excess bleeding (adjusted OR 1.86, 95% CI 0.58-5.93, p = 0.3), ischaemic outcomes (adjusted OR, 95% CI, p = 0.12) or in-hospital mortality (adjusted OR, 95% CI, p = 0.11). Older patients having primary PCI had higher risk of bleeding irrespective of abciximab use (adjusted p = 0.042). CONCLUSION: Abciximab may not be associated with excess bleeding complications in older patients compared with younger individuals and may be safe to use in older people if indicated.

Single donor-derived strongyloidiasis in three solid organ transplant recipients: case series and review of the literature.

Donor-derived Strongyloides stercoralis infections in transplant recipients are a rare but recognized complication. In this case series, we report donor-derived allograft transmission of Strongyloides in three solid organ transplant recipients. Following detection of infection in heart and kidney-pancreas recipients at two different transplant centers, a third recipient from the same donor was identified and diagnosed. S. stercoralis larvae were detected in duodenal aspirates, bronchial washings, cerebrospinal fluid, urine and stool specimens. Treatment with ivermectin and albendazole was successful in two of the three patients identified. The Centers for Disease Control and Prevention was contacted and performed an epidemiologic investigation. Donor serology was strongly positive for S. stercoralis antibodies on retrospective testing while all pretransplant recipient serum was negative. There should be a high index of suspicion for parasitic infection in transplant recipients and donors from endemic regions of the world. This case series underscores the need for expanded transplant screening protocols for Strongyloides. Positive serologic or stool tests should prompt early treatment or prophylaxis in donors and recipients as well as timely notification of organ procurement organizations and transplant centers.

Phase diagram of a three-orbital model for high-Tc cuprate superconductors.

We study the phase diagram of an effective three-orbital model of the cuprates using variational Monte Carlo calculations on asymptotically large lattices and exact diagonalization on a 24-site cluster. States with ordered orbital current loops (LC), itinerant antiferromagnetism, d-wave superconductivity, and the Fermi liquid are investigated using appropriate Slater determinants refined by Jastrow functions for on-site and intersite correlations. We find an LC state stable in the thermodynamic limit for a range of parameters compatible with the Fermi surface of a typical hole doped superconductor provided the transfer integrals between the oxygen atoms have signs determined by the effects of indirect transfer through the Cu-4s orbitals as suggested by Andersen. The results of the calculations are that the LC phase gives way at lower dopings to an antiferromagnetism phase, and at larger dopings to superconductivity and Fermi liquid phases.

Landau renormalizations of superfluid density in the heavy-fermion superconductor CeCoIn5.

The formation of heavy-fermion bands can occur by means of the conversion of a periodic array of local moments into itinerant electrons via the Kondo effect and the huge consequent Fermi-liquid renormalizations. Leggett predicted for liquid (3)He that Fermi-liquid renormalizations change in the superconducting state, leading to a temperature dependence of the London penetration depth Λ quite different from that in BCS theory. Using Leggett's theory, as modified for heavy fermions, it is possible to extract from the measured temperature dependence of Λ in high quality samples both Landau parameters F(0)(s) and F(1)(s); this has never been accomplished before. A modification of the temperature dependence of the electronic specific heat C(el), related to that of Λ, is also expected. We have carefully determined the magnitude and temperature dependence of Λ in CeCoIn(5) by muon spin relaxation rate measurements to obtain F(0)(s) = 36 ± 1 and F(1)(s) = 1.2 ± 0.3, and we find a consistent change in the temperature dependence of C(el). This, the first determination of F(1)(s) with a value ≪ F(0)(s) in a heavy-fermion compound, tests the basic assumption of the theory of heavy fermions, that the frequency dependence of the self-energy is much more important than its momentum dependence.

Sharp low-energy feature in single-particle spectra due to forward scattering in d-wave cuprate superconductors.

There is an enormous interest in the renormalization of the quasiparticle (qp) dispersion relation of cuprate superconductors both below and above the critical temperature T_{c} because it enables the determination of the fluctuation spectrum to which the qp's are coupled. A remarkable discovery by angle-resolved photoemission spectroscopy (ARPES) is a sharp low-energy feature (LEF) in qp spectra well below the superconducting energy gap but with its energy increasing in proportion to T_{c} and its intensity increasing sharply below T_{c}. This unexpected feature needs to be reconciled with d-wave superconductivity. Here, we present a quantitative analysis of ARPES data from Bi_{2}Sr_{2}CaCu_{2}O_{8+δ} (Bi2212) using Eliashberg equations to show that the qp scattering rate due to the forward scattering impurities far from the Cu-O planes is modified by the energy gap below T_{c} and shows up as the LEF. This is also a necessary step to analyze ARPES data to reveal the spectrum of fluctuations promoting superconductivity.

Coexistence of two sharp-mode couplings and their unusual momentum dependence in the superconducting state of Bi2Sr2CaCu2O(8+δ) revealed by laser-based angle-resolved photoemission.

High-resolution laser-based angle-resolved photoemission measurements have been carried out on Bi2Sr2CaCu2O(8+δ) (Bi2212) superconductors to investigate momentum dependence of electron coupling with collective excitations (modes). Two coexisting energy scales are clearly revealed over a large momentum space for the first time in the superconducting state of the overdoped Bi2212 superconductor. These two energy scales exhibit distinct momentum dependence: one keeps its energy near 78 meV over a large momentum space while the other changes its energy from ∼40 meV near the antinodal region to ∼70 meV near the nodal region. These observations provide a new picture on momentum evolution of electron-boson coupling in Bi2212 that electrons are coupled with two sharp modes simultaneously over a large momentum space in the superconducting states. Their unusual momentum dependence poses a challenge to our current understanding of electron-mode-coupling and its role for high-temperature superconductivity in cuprate superconductors.

Digital infrared thermal imaging of udder skin surface temperature: a novel non-invasive technology to monitor calving process in Murrah buffalo (Bubalus bubalis).

Quantifiable decline in the maternal body temperature during the pre-calving offers the possibilities for predicting the calving that can improve the calving management. As infrared thermography (IRT) is a simple non-contact tool for precise measurement of surface temperature, we investigated the use of IRT to establish thermal signatures around calving in the Murrah buffalo. The IRT of eye, right lateral, left lateral and rear side of udder skin surface temperature (USST) were recorded at 6 h interval from 96 h before the expected date of calving, at the time of calving and 24 h post-calving in Murrah buffaloes (n = 28). In parallel, blood samples were collected for progesterone (P4) assay. The results revealed that the IRT of the eye, right and left lateral and rear side of USST showed a significant decrease in the temperature from 48 h pre-calving till the onset of calving with a ΔT (°C) of 0.56, 0.91, 0.70, and 0.90, respectively. Mean USST significantly declined from 48 h pre-calving with a ΔT of 0.85 °C. The residual temperature of both eye and various ROI of the udder also followed a similar and significant declining trend from 48 to 0 h of calving indicating that circadian influence on the USST was minimum. Plasma P4 concentration significantly decreased from 72 h pre-calving till calving. It is concluded that a marked reduction in the IRT of the USST at 6-12 h pre-calving would be useful in predicting the onset of calving in the Murrah buffalo.

Considerations on the mechanisms and transition temperatures of superconductivity induced by electronic fluctuations.

An overview of the momentum and frequency dependence of effective electron-electron interactions which favor electronic instability to a superconducting state in the angular-momentum channel ℓ and the properties of the interactions which determine the magnitude of the temperature T(c) of the instability is provided. Interactions induced through exchange of electronic fluctuations of spin density, charge density or current density are considered. Special attention is paid to the role of quantum-critical fluctuations (QCFs) including pairing due to their virtual exchange as well as de-pairing due to inelastic scattering. Additional insight is gained by reviewing empirical data and theory specific to superfluidity in liquid He(3), superconductivity in some of the heavy-fermion compounds, in cuprates, in pncitides and the valence skipping compound. The physical basis for the following observation is provided: the ratio of the maximum T(c) to the typical phonon frequency in phonon induced s-wave superconductivity is O(10(-1)); the ratio of p-wave T(c) to the renormalized Fermi energy in liquid He(3), a very strongly correlated Fermi liquid near its melting pressure, is only O(10(-3)); in the cuprates and the heavy fermions where d-wave superconductivity occurs in a region governed by QCFs, this ratio rises to O(10(-2)). These discussions also suggest factors important for obtaining higher T(c). Experiments and theoretical investigations are suggested to clarify the many unresolved issues.

Collective modes in the loop ordered phase of cuprate superconductors.

We show that the two branches of collective modes discovered recently in underdoped cuprates with a large spectral weight are a necessary consequence of the loop-current state. Such a state has been shown in earlier experiments to be consistent with the symmetry of the order parameter competing with superconductivity in four families of cuprates. We also predict a third branch of excitations which cannot be discovered by neutron scattering but may be discovered by other techniques. Using parameters to fit the observed modes, we show that quantum fluctuations change the direction of the effective moments in the ground state to lie at an angle to the c axis as observed in experiments.

Differences between South Asians and White Europeans in five year outcome following percutaneous coronary intervention.

AIMS: The aim of this study was to compare rates of target lesion revascularisation (TLR) and total mortality between South Asians (SAs) and White Europeans (WEs) following percutaneous coronary intervention (PCI). METHODS: We followed a cohort of 293 SAs and 865 WEs patients admitted for elective or urgent PCI to de novo lesions. For each patient, baseline cardiovascular risk factors and angiographic data were obtained. Patients had long-term follow-up for all-cause mortality and TLR. RESULTS: Patients were followed up over a median period of 54 months (inter-quartile range: 47-65). SAs were younger (62 ± 12 years vs. 66 ± 11 years; p < 0.0001), with a higher prevalence of diabetes, greater social deprivation [Carstairs score: 10.2 (IQR 6.5-12.1) vs. 3.3 (IQR 0.9-6.5); p < 0.0001] and presented more acutely (urgent PCI procedure). During the follow-up period, a total of 119 deaths and 111 TLR [94 repeat PCI and 17 coronary artery bypass grafting (CABG)] occurred. There was no significant difference in the rate of long-term all-cause mortality between SA and WE [31 (10.6%) vs. 107 (12.4%); OR: 0.84 (0.55-1.28); p = 0.47]. However, SA ethnicity was an independent predictor of long-term TLR, after adjusting for baseline clinical and procedural characteristics [54 (18.4%) vs. 57 (6.6%); OR: 2.83 (1.87-4.29); p < 0.0001]. CONCLUSIONS: South Asian patients were more likely to require re-admission to treat clinical restenosis of the index lesion. There was no significant long-term difference in all-cause mortality between SA and WE patients.

Effects of atorvastatin on circulating CD34+/CD133+/ CD45- progenitor cells and indices of angiogenesis (vascular endothelial growth factor and the angiopoietins 1 and 2) in atherosclerotic vascular disease and diabetes mellitus.

BACKGROUND: Cardiovascular disease (CVD) remains a major cause of morbidity and mortality, especially in the presence of diabetes, possibly because of endothelial damage. Increased circulating progenitor cells (CPCs) and increased plasma markers of angiogenesis [vascular endothelial growth factor (VEGF) and the angiopoietins (Ang-1 and -2)] may be evidence of this damage. Treatment with hydroxy-methyl-glutaryl (HMG-CoA) reductase inhibitors ('statins') improves outcomes in patients with vascular disease, including diabetic patients. We hypothesized that 80 mg per day atorvastatin influences CPC counts of VEGF and the angiopoietins in patients with atherosclerotic CVD with or without diabetes mellitus. METHODS: Cardiovascular disease patients with diabetes mellitus (Group A, n = 14) and nondiabetic patients with CVD only (Group B, n = 10) took atorvastatin 80 mg per day for a period of 8-10 weeks. CPCs (CD34+/CD133+/CD45-) were defined by flow cytometry, plasma levels VEGF and Ang-1 and Ang-2 by ELISA). RESULTS: Circulating progenitor cell counts increased (P < 0.001) in Group A compared with a nonsignificant change in Group B (P = 0.37). VEGF levels fell significantly in Group A (P = 0.04) but no significant change was seen in Group B (P = 0.16). Whilst Ang-1 remained unchanged (P = 0.41), Ang-2 levels increased markedly in both groups (P < 0.05). These effects were independent of LDL and total cholesterol changes but were associated with HDL changes. CONCLUSION: High-dose atorvastatin increased circulating CPCs, reduced VEGF and increased Ang-2 in patients with diabetes and CVD, providing another possible pathophysiological mechanism for the beneficial effects of statins in CVD.

Normal coronary angiography and primary percutaneous coronary intervention for ST elevation myocardial infarction: a literature review and audit findings.

It is becoming increasingly common to offer primary percutaneous coronary intervention as first line treatment for ST elevation myocardial infarction (STEMI). In a subset of patients presenting with suspected STEMI, coronary arteries appear normal at coronary angiography. In this article, the current literature of this group of patients is reviewed. The incidence of 'normal' angiography, the clinical and electrocardiographic features of this group of patients and the alternative diagnoses for presentation are discussed. This article reviews the factors leading to such presentation, the clinical characteristics of such patients and the implications, clinical and economic.

Effects of coronary artery disease and percutaneous intervention on the cardiac metabolism of nonesterified fatty acids and insulin: Implications of diabetes mellitus.

BACKGROUND: Nonesterified fatty acids (NEFA) and insulin have been implicated in the pathogenesis of diabetes mellitus (Type 2 diabetes) and coronary artery disease (CAD). We hypothesized that intracardiac levels of insulin and NEFA within the aortic root, coronary sinus and systemic venous levels would be different in patients with coronary atherosclerosis and/or diabetes. We also studied the metabolic cardiac response following percutaneous coronary intervention (PCI). METHODS: A total of 67 subjects (42 males; mean age 60 +/- 11 years) were recruited, of which three groups were identified: Group I - those with no CAD or Type 2 diabetes (n = 17); Group II - those with CAD but no Type 2 diabetes (n = 40); and Group III - patients with Type 2 diabetes and CAD (n = 10). Of the whole cohort, 34 patients (51%) proceeded to PCI. NEFA and insulin levels were analysed using enzymatic colorimetric and a monoclonal immuno-autoanalyser techniques, respectively. Subsequently, fractional extraction (FFE) of both variables was calculated. RESULTS: Nonesterified fatty acids and insulin concentrations were lower in the aortic root versus coronary sinus (both P < 0.05). FFE of NEFA was 2x higher in Group I (P < 0.01) with a sevenfold reduction in insulin FFE in Group III. Following PCI, systemic NEFA levels increased significantly (P < 0.05) with no significant change seen within the coronary sinus (P = NS), whilst a reduction in insulin concentrations at all three sites was observed (all P < 0.01). No significant difference in FFE of NEFA was seen after PCI when comparing Groups II and III. There was a drop in insulin extraction in Group II (nondiabetic subjects, from 12% to -4%, P = 0.04), compared with an increase seen in Group III (Type 2 diabetes patients, from -4% to 3%, P = 0.03). CONCLUSION: There is an intracardiac gradient of NEFA and insulin in Groups I-III. Cardiac NEFA metabolism was higher in those with mild CAD compared with those with obstructive CAD whereas intracardiac insulin extraction was lower in Group III (diabetic) patients. PCI was associated with a systemic rise in NEFA, with a reduction in insulin levels and cardiac utilization, but these effects were blunted in diabetic patients.

Superconductivity in the fullerenes.

Intramolecular vibrations strongly scatter electrons near the Fermi-surface in doped fullerenes. A simple expression for the electron-phonon coupling parameters for this case is derived and evaluated by quantum-chemical calculations. The observed superconducting transition temperatures and their variation with lattice constants can be understood on this basis. To test the ideas and calculations presented here, we predict that high frequency H(2) modes acquire a width of about 20% of their frequency in superconductive fullerenes, and soften by about 5% compared to the insulating fullerenes.

High-risk myocardial infarction patients appear to derive more mortality benefit from short door-to-balloon time than low-risk patients.

OBJECTIVES: To evaluate reduction of door-to-balloon (DTB) time and its impact on in-hospital mortality of high-risk infarct patients in a collaboration of district general hospitals (DGH) with a physician-to-patient model. METHODS: Primary percutaneous coronary interventions (PPCI) with short DTB time offer mortality benefit for ST-segment elevation myocardial infarction but literatures are conflicting on this benefit for high- vs. low-risk patients. In a unique model at Sandwell and West Birmingham Hospitals, five interventional cardiologists provide 24-h PPCI at whichever one of its two DGH that patients present to. A retrospective audit was performed on 3 years (July 2005-June 2008) of PPCI data in the British Cardiovascular Intervention Society database. Data were analysed in four periods corresponding to change from daytime-only to 24-h PPCI. DTB time and in-hospital mortality were the main outcome measures. RESULTS: Of the 459 patients, median DTB time improved from 89 min (interquartile range: 49-120) to 68 min (50-91) (p = 0.005) and proportion of patients achieving target 90-min DTB time increased from 53% (21/40) to 75% (93/124) (p = 0.005). In-hospital mortality was less for short DTB time [4.6% (13/284) vs. 11.5% (20/174); odds ratio (OR) 0.37, 95% confidence interval (CI): 0.18-0.75; p = 0.008]. With the proviso that our study was limited in power, long DTB time (> 90 min vs. < or = 90 min) was associated with higher in-hospital mortality in high-risk patients [15.6% (20/128) vs. 7.1% (12/168); OR 2.41, 95% CI: 1.14-5.06; p = 0.024] and not in low-risk patients [0% (0/46) vs. 0.9% (1/117); OR 0, 95% CI: 0-9.88; p = 1.000]. CONCLUSIONS: A collaboration of DGH with a physician-to-patient model can deliver timely PPCI that appear to translate into mortality benefit more so in high-risk patients. Low-risk patients would therefore probably tolerate delays associated with transfer to large centres while high-risk patients would not and need alternative strategy. A collaboration of smaller hospitals with a pool of mobile interventional cardiologists could be such an alternative.

Transcatheter device closure of atrial septal defects in the elderly: technical considerations and short-term outcomes.

BACKGROUND: Device closure of an atrial septal defect (ASD) results in symptom-reduction, right heart remodelling and lower pulmonary artery pressures. However it is unclear if there is a chronological limit to these benefits and whether device closure is safe in elderly subjects. The aim of this study was, therefore, to assess the safety and efficacy of device closure in patients >60 years. METHODS: Retrospective study of Amplatzer Septal Occluder device closures from a single institution (May 1999-August 2002). RESULTS: Fifty subjects aged >60 years (range 60-85 years) had ASD device closure (27% of the total cohort). Defect size and shunt size were similar for both younger and older groups (2.2:1 in both groups, p=0.9) as were procedural duration, fluoroscopy time and device size deployed. Baseline right ventricular (RV) systolic pressure ((younger vs. older) 39 vs. 49 mmHg, p<0.001) and right ventricular size (45 vs. 51 mm, p<0.001) were greater in the older group. Following closure RV systolic pressure (49 vs. 45 mmHg, p<0.01) and RV size (51 vs. 44 mm, p=0.01) decreased in the older group. CONCLUSION: Device closure of an ASD can be performed safely in older patients. The right heart shows signs of remodelling even in elderly subjects.