Structure and Oxygen Affinity of Crystalline des-His-146β Human Hemoglobin in the T State *

To correlate directly structure with function, the oxygen affinity and the three-dimensional structure of crystals of the T quaternary state of des-His-146beta human hemoglobin have been determined by polarized absorption microspectrophotometry and x-ray diffraction crystallography. In des-His-146beta, the COOH-terminal histidine residues of the beta chains of hemoglobin A have been removed. Oxygen binding to crystalline des-His hemoglobin is non-cooperative and independent of pH. The oxygen affinity is 1.7-fold greater than that of the crystalline state of hemoglobin A. Removal of His-146beta results in a small movement of the truncated COOH-terminal peptide and in a very small change in quaternary structure. Previously, similar studies on T state crystals of des-Arg-141alpha hemoglobin showed that removal of the COOH termini of the alpha chains results in much larger effects on oxygen affinity and on quaternary structure. Kinetic studies in solution reveal that at pH 7.0, the rates of CO combination with deoxygenated des-His-146beta in the absence and presence of inositol hexaphosphate are 2.5- and 1.3-fold, respectively, more rapid than for hemoglobin A. The values for des-Arg are 7.6- and 3.9-fold. The properties of the T state of hemoglobin both in the crystal and in solution are influenced to a greater degree by the interactions associated with Arg-141alpha than those associated with His-146beta

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Archivio storico per le province napoletane. A.18, n.1/4 (1893)

A.18, n.1 (1893): E. Nunziante, I primi anni di Ferdinando d’Aragona e l’invasione di Giovanni Angiò (continua), P. 3-40 ; M. Schipa, Il Ducato di Napoli (continua), P. 41-65 ; E. Celani, Documenti vaticani per la storia della contea di Celano (1184-1594) con un facsimile, P. 66-91 ; N. Barone, Lucio Giovanni Scoppa, grammatico napoletano nel secolo XVI, P. 92-103 ; B. Capasso, Pianta della città di Napoli nel secolo XI (continua), P. 104-125 ; Rassegna bibliografica 1891-1892, P. 126-182.A.18, n.2 (1893): E. Nunziante, I primi anni di Ferdinando d’Aragona e l’invasione di Giovanni Angiò (continua), P. 205-246 ; M. Schipa, Il Ducato di Napoli (continua), P. 247-277 ; E. Cocchia, Napoli e il Satyricon di petronio Arbitro, P. 278-315 ; B. Capasso, Pianta della città di Napoli nel secolo XI (continuazione e fine), P. 316-363 ; A. Sambon, Tre monete inedite di Carlo III di Durazzo e una moneta d’oro sconosciuta di pesto, P. 364-373 ; A. Sambon, statero d’oro di Posidonia, P. 374-379 ; N. Arnone, Le regie tombe del Duomo di Cosenza, P. 380-408.A.18, n.3 (1893): E. Nunziante, I primi anni di Ferdinando d’Aragona e l’invasione di Giovanni Angiò (continua), P. 411-462 ; M. Schipa, Il Ducato di Napoli (continua), P. 463-493 ; B. Maresca, Il cavaliere Antonio Micheroux nella reazione napoletana dell’anno 1799 (continua), P. 494-536 ; E. Percopo, Nuovi documenti su gli scrittori e gli artisti dei tempi aragonesi (continua), P. 527-537 ; Elenco pergamene già appartenenti alla famiglia Fusco, P. 538-555.A.18, n.4 (1893): E. Nunziante, I primi anni di Ferdinando d’Aragona e l’invasione di Giovanni Angiò (continua), P. 561-620 ; M. Schipa, Il Ducato di Napoli (continua), P. 621-651 ; B. Maresca, Il cavaliere Antonio Micheroux nella reazione napoletana dell’anno 1799 ( continua), P. 652-699 ; D. B., L’assedio di Capua nel 1743, P. 700-768 ; A. Sogliano Miscellanea epigrafica napoletana, Contributo alla storia e topografia antica di Napoli (continua), P. 769-783 ; E. Percopo, Nuovi documenti sugli scrittori e gli artisti dei tempi aragonesi (continua), P. 784-812