The Impact of Hypothyroidism on Clinical Outcomes in Patients Undergoing Percutaneous Coronary Intervention

Introduction: Hypothyroidism either subclinical (SCH) or overt is independently associated with an increased risk of coronary artery disease (CAD). The combined effects of SCH and overt hypothyroidism on clinical outcomes after percutaneous coronary intervention (PCI) are largely unknown. Aim: The aim of the study is to assess the impact of subclinical and overt hypothyroidism among patients presenting with CAD undergoing PCI. Materials and Methods: A total of 102 patients who were referred to the Madras Medical Mission Hospital for PCI from September 2020 to March 2021 were enrolled in the study. These patients were categorized into three groups. Each group has 34 patients and was followed for one year. Group 1: Patients with normal TSH levels (TSH-0.45 -5mlU/Liter) and euthyroid at T3, T4 levels. Group 2: Patients with subclinical hypothyroidism with elevated TSH levels (TSH=5-15mlU/liter) and normal thyroid with T3, T4 levels. Group 3: Patients with a family history of overt hypothyroidism or high TSH levels(<15mlU/liter) and low T3 and T4 levels [16]. Results: We applied ANOVA to find the PCI outcomes. A p-value of <0.05 was accepted as significant. Age (p-0.03), recent myocardial infarction (p-0.04), diabetes mellitus (p<0.001), HbA1C (p-0.012), and systolic blood pressure (p-0.04) were found to be significant. Post-PCI bleeding complications (p<0.001) during one month, six months, and one-year follow-up were the main observation of the study. Conclusion: The prior history of DM and elevated HbA1c levels observed in the overt hypothyroid group indicate that DM was one of the key factors associated with overt hypothyroidism. Despite the fact that PCI was safe for patients with hypothyroidism, the risk of early post-PCI bleeding was of concern

Crystallization and preliminary diffraction analysis of an engineered cephalosporin acylase

Crystallization conditions are reported for an engineered cephalosporin acylase based on the sequence of glutaryl-7-aminocephalosporanic acid acylase from Pseudomonas strain N176

Untersuchungen zur Bedeutung des präpartalen Progesteronentzugs in Hinblick auf die Steuerung der Geburt und die Ablösung der Nachgeburt beim Rind

Beim Rind ist der präpartale Abfall der maternalen Progesteron (P4)-Konzentration Voraussetzung für den Eintritt der Geburt. Der P4-Abfall spiegelt beim Rind primär den Funktionsverlust des Trächtigkeitsgelbkörpers wider. Über die Bedeutung der plazentaren P4-Produktion lagen bisher praktisch keine Informa¬tionen vor. Die Rinder¬plazenta trägt in der Endphase der Gravidität zwar nur minimal zu den maternalen P4-Spiegeln bei, jedoch bildet sie hohe lokale P4-Konzentrationen im Bereich der feto-maternalen Kontakt¬zone. Diese könnten, vermittelt über P4-Rezeptoren (PR) in den maternalen Karunkeln, ein wesentlicher Faktor für die Differenzie¬rung und Funktion der Plazentome sein. Es wurde die Arbeits¬hypothese ent¬wickelt, dass der Entzug hoher lokaler P4-Konzentrationen ein wesentliches Signal für die Vorbereitung eines termin¬gerechten Nachgeburtsabganges darstellt. Entsprechend könnte ein unvollständiges Sistieren der plazentaren P4-Produktion vor der Geburt eine wesentliche Ursache für das Auftreten idiopathischer Nachge-burts¬verhaltungen sein. Zur Überprüfung dieser Hypo¬these wurden drei gravide Kühe am 270. und 271. Graviditätstag mit dem Antigestagen Aglepriston (Ap) behandelt (Gruppe D272+Ap). Dieser PR-Blocker ermöglicht die Ausschaltung aller rezeptor¬vermittelten P4-Wirkungen unabhängig von der P4-Quelle. Als Kontrollen dienten Tiere mit termin¬gerechter spontaner Geburt und termingerechtem Nachgeburts¬abgang (Gruppe Normalgeburt, n = 4, Trächtigkeitsdauer: 280,5 ± 1,7 Tage) sowie unbehan¬delte Tiere mit Schnitt¬entbindung am Tag 272 (Gruppe D272-Ap, n = 3). Die Kühe wurden klinisch überwacht und der Geburtsverlauf dokumentiert. Von allen Tieren wurden Blutproben in regelmäßigen Abständen sowie Plazentome unmittelbar im Anschluss an die Geburt (Gruppen D272+Ap und Normalgeburt) bzw. während der Schnittentbindungen (Gruppe D272-Ap) entnommen. In den Blutproben wurden die Konzentrationen von Progesteron und Östrogenen mittels radioimmuno¬logischer Verfahren und die 13, 14-Di¬hydro-15-Keto-PGF2α (PGFM)-Konzentrationen mittels ELISA gemessen. Als Parameter für die präpartale Umstrukturierung der Plazentome wurde der prozen¬tuale Anteil der Trophoblast-riesenzellen (TGC) an den Trophoblastzellen und die Reduktion des Karunkelepithels erfasst. Weiterhin wurde die Expression von Cyclooxygenase II (Cox II), PR und Glucocorticoidrezeptor (GR) auf Protein- und mRNA-Ebene beurteilt. Die Aglepristonbehandlung führte bei allen drei Kühen zu einer vorzeitigen Terminie¬rung der Gravidität. Erste Geburtsanzeichen traten 46,3 ± 6,0 Stunden nach Be¬handlungsbeginn auf. Es kam zur vollständigen Öffnung der Zervix, eine adäquate Wehentätigkeit setzte jedoch innerhalb der folgenden zwei Stunden nicht ein. So wurde ein manueller Auszug der Kälber durchgeführt. Neben der Öffnung der Zervix wurde durch die Antigestagenbehandlung die Laktogenese induziert. Entge¬gen der eigenen Hypothese wiesen alle drei Kühe der Gruppe D272+Ap, wie die Tiere der Gruppe D272-Ap, eine komplette Nachgeburts¬ver¬haltung auf und die Kälber beider Gruppen waren gleichermaßen prämatur. Die histo¬morphologischen Unter¬suchungen bestätigten, dass durch die Aglepriston¬behand¬lung die präpartale „Plazentareifung“ nicht induziert wurde. So waren, im Gegensatz zur Normalgeburtsgruppe, in den unreifen Plazentomen der Gruppen D272+Ap und D272−Ap weder ein Rück¬gang des relativen Anteils der TGC noch eine Reduktion des Karunkelepithels nach¬weisbar. Überraschenderweise wurde durch die Antigestagenbehandlung die Luteolyse induziert, erkennbar an einem steilen Abfall der P4-Werte vor bzw. während des Auszugs der Kälber. Korrespondierend mit dem Abfall der P4-Konzen¬tra¬tionen wurde bei den Tieren der Gruppe D272+Ap bereits präpartal ein schwacher Anstieg der PGFM-Werte beobachtet. Da bei diesen Tieren, im Gegensatz zur Normal¬geburtsgruppe, keine Aufregulation der plazentaren Cox II-Expression nach¬weisbar war, ist anzunehmen, dass die Antigestagen-induzierte Luteolyse indirekt durch Prostaglandine extraplazentaren, vermutlich endometrialen, Ursprungs aus¬gelöst wurde. Zum Zeitpunkt des Auszugs waren die PGFM-Plasma¬konzentrationen im Vergleich zur Normalgeburtsgruppe jedoch relativ gering (2,14 ± 1,40 ng/ml vs. 8,70 ± 2,20 ng/ml). Somit erklärt vermutlich ein Mangel an uterotonem PGF2α die Wehen¬schwäche bei den Aglepriston-behandelten Tieren. Die Östrogen¬synthese im Trophoblasten sowie die GR- bzw. PR-Expression in den Plazentomen wurden durch das Antigestagen nicht beeinflusst. Insgesamt lassen die Ergebnisse dieser Arbeit darauf schließen, dass nur ein relativ geringer Anteil der geburtsassoziierten Veränderungen direkt durch den präpartalen Progesteronentzug ausgelöst wird, nämlich die Öffnung der Zervix und das Einsetzen der Laktation. Dagegen erfordern andere wesentliche geburtsassoziierte Vorgänge, wie eine adäquate Wehentätigkeit und die Ablö¬sung der Plazenta, offensichtlich primär Signale aus dem fetalen Kompartiment. Die eigenständige Bedeutung der plazentaren P4¬-Produktion bleibt unklar.In cattle the prepartal decline in maternal progesterone (P4) levels is a prerequisite for the onset of parturition. This P4 withdrawal predominantly reflects the loss of luteal function, and virtually no information on the importance of placental P4 production is available. Despite its minimal contribution to maternal P4 levels in late gestation the bovine placenta is capable of producing high P4 levels locally at the feto-maternal interface, which – mediated by progesterone receptors (PR) previously detected in the maternal caruncles – could be an essential factor in placental differentiation and function. Thus, the hypothesis was put forward that a well-timed and complete withdrawal of high local P4 concentrations is a crucial signal for the timely release of the placenta. According to this concept, an incomplete cessation of placental P4 production during the initiation of parturition could be an important factor in the etiology of placental retention. To test for this hypothesis, three cows were treated with the antiprogestin aglepristone (Ap) on days 270 and 271 of gestation to abolish receptor mediated effects of P4 irrespective of its origin (group D272+Ap). As controls, four cows giving spontaneous birth at normal term (280.5 ± 1.7 days, group NT) with timely release of fetal membranes and three cows undergoing cesarean section on day 272 (group D272-Ap) were included into the study. The cows were monitored clinically, and the progress of birth was registered. From all animals, blood samples were taken regularly during the experimental period, and placentomes were removed per vaginam immediately after birth (groups D272+Ap and NT) or during cesarean section (group D272-Ap). In blood samples, con-centrations of P4 and estrogens were measured by radioimmunological methods, and for the measurement of 13, 14-dihydro-15-keto prostaglandin F2α (PGFM)-concentrations a commercial ELISA kit was used. To characterize the prepartal remodeling of placentomal microarchitecture, the percentage of trophoblast giant cells (TGC) relative to the total number of trophoblast cells and the reduction of caruncular epithelium were determined. Moreover, the expression of cyclo-oxygenase II (Cox II), PR and glucocorticoid receptor (GR) was investigated at protein and mRNA level. The application of aglepristone significantly reduced gestational length. First signs of impending parturition occurred 46.3 ± 6.0 hours after the start of treatment, and vaginal exploration confirmed that the cervix was fully open during this time. However, no progress in the expulsion of the calves could be observed during the following two hours, obviously due to insufficient myometrial activity. Consequently the calves were extracted. Besides a complete opening of the cervix, antiprogestin treatment induced the onset of lactation. Inconsistent with the working hypothesis, in all cows of the treatment group a severe retention of fetal membranes was observed. Similar cases of retained fetal membrane were also observed in all D272-Ap cows, and calves of both groups were slightly premature to a similar extent. Consistent with clinical observations histological investigations of placentomes showed that antiprogestin treatment did not induce placental maturation, whereas for the placentomes of NT cows the prepartal decline in TGC numbers and the reduction of caruncular epithelium was confirmed. Surprisingly, antiprogestin treatment induced luteolysis, as a significant decline of progesterone concentrations started before or during the expulsion of the calf. Con¬comitant with the decline in P4 concentrations in D272+Ap cows an increase of PGFM levels became detectable. The fact that, different from NT animals, no up-regu¬lation of placental Cox II was found suggests that the antiprogestin induced luteolysis indirectly stimulated prostaglandin pro¬duction from an extraplacental source, presumably the intercaruncular endometrium. However, at parturition PGFM levels in D272+Ap cows were clearly lower in comparison to NT cows (2.14 ± 1.40 ng/ml vs. 8.70 ± 2.20 ng/ml), which suggests that insufficient myometrial activity observed in antiprogestin treated cows was related to a reduced availability of uterotonic PGF2α. Placental estrogen production and the expression of PR or GR were not affected by antiprogestin treatment. In conclusion, the results demonstrate that only a minor part of the processes related to bovine parturition is directly dependent on P4 withdrawal, in particular the opening of the cervix and the onset of lactation. Moreover, they suggest that other important processes such as adequate myometrial activity and timely release of the placenta are predominantly dependent on signals from the fetal compartment. The importance of placental P4 production in cattle remains unknown

Structure of a lipid A phosphoethanolamine transferase suggests how conformational changes govern substrate binding

Multidrug-resistant (MDR) gram-negative bacteria have increased the prevalence of fatal sepsis in modern times. Colistin is a cationic antimicrobial peptide (CAMP) antibiotic that permeabilizes the bacterial outer membrane (OM) and has been used to treat these infections. The OM outer leaflet is comprised of endotoxin containing lipid A, which can be modified to increase resistance to CAMPs and prevent clearance by the innate immune response. One type of lipid A modification involves the addition of phosphoethanolamine to the 1 and 4′ headgroup positions by phosphoethanolamine transferases. Previous structural work on a truncated form of this enzyme suggested that the full-length protein was required for correct lipid substrate binding and catalysis. We now report the crystal structure of a full-length lipid A phosphoethanolamine transferase from Neisseria meningitidis, determined to 2.75-Å resolution. The structure reveals a previously uncharacterized helical membrane domain and a periplasmic facing soluble domain. The domains are linked by a helix that runs along the membrane surface interacting with the phospholipid head groups. Two helices located in a periplasmic loop between two transmembrane helices contain conserved charged residues and are implicated in substrate binding. Intrinsic fluorescence, limited proteolysis, and molecular dynamics studies suggest the protein may sample different conformational states to enable the binding of two very different- sized lipid substrates. These results provide insights into the mechanism of endotoxin modification and will aid a structure-guided rational drug design approach to treating multidrug-resistant bacterial infectionsThis work was supported by National Health and Medical Research Council of Australia Grants APP1003697 (to A.V. and C.M.K.), APP1078642 (to A.V., C.M.K., and K.A.S.), and APP1049685 (to M.L.O.); the Research Service of the US Department of Veterans Affairs Merit Review Award BX000727 (to G.A.J.); and the Welcome Trust Grant 099165/Z/12/Z (to Prof. S. Iwata and I.M.). We acknowledge the Australian Research Council for Infrastructure Grant LE120100092 (to A.V. and K.A.S.) and Fellowship Awards FT100100291 (to K.A.S.) and DE120101550 (to M.L.O.). A.A. and S.S.W. acknowledge the University of Western Australia for support through Australian Postgraduate Awards, a Fay Gale Fellowship, and a Bruce and Betty Green Scholarship. This work used resources from the National Computational Infrastructure, supported by the Australian Government

Structure of a lipid A phosphoethanolamine transferase suggests how conformational changes govern substrate binding

Multidrug-resistant (MDR) gram-negative bacteria have increased the prevalence of fatal sepsis in modern times. Colistin is a cationic antimicrobial peptide (CAMP) antibiotic that permeabilizes the bacterial outer membrane (OM) and has been used to treat these infections. The OM outer leaflet is comprised of endotoxin containing lipid A, which can be modified to increase resistance to CAMPs and prevent clearance by the innate immune response. One type of lipid A modification involves the addition of phosphoethanolamine to the 1 and 4′ headgroup positions by phosphoethanolamine transferases. Previous structural work on a truncated form of this enzyme suggested that the full-length protein was required for correct lipid substrate binding and catalysis. We now report the crystal structure of a full-length lipid A phosphoethanolamine transferase from Neisseria meningitidis, determined to 2.75-Å resolution. The structure reveals a previously uncharacterized helical membrane domain and a periplasmic facing soluble domain. The domains are linked by a helix that runs along the membrane surface interacting with the phospholipid head groups. Two helices located in a periplasmic loop between two transmembrane helices contain conserved charged residues and are implicated in substrate binding. Intrinsic fluorescence, limited proteolysis, and molecular dynamics studies suggest the protein may sample different conformational states to enable the binding of two very different-sized lipid substrates. These results provide insights into the mechanism of endotoxin modification and will aid a structure-guided rational drug design approach to treating multidrug-resistant bacterial infections. lipid modification | multidrug resistance | molecular dynamics | Neisseria | membrane protein structur

Structure of a lipid A phosphoethanolamine transferase suggests how conformational changes govern substrate binding

Multidrug-resistant (MDR) gram-negative bacteria have increased the prevalence of fatal sepsis in modern times. Colistin is a cationic antimicrobial peptide (CAMP) antibiotic that permeabilizes the bacterial outer membrane (OM) and has been used to treat these infections. The OM outer leaflet is comprised of endotoxin containing lipid A, which can be modified to increase resistance to CAMPs and prevent clearance by the innate immune response. One type of lipid A modification involves the addition of phosphoethanolamine to the 1 and 4′ headgroup positions by phosphoethanolamine transferases. Previous structural work on a truncated form of this enzyme suggested that the full-length protein was required for correct lipid substrate binding and catalysis. We now report the crystal structure of a full-length lipid A phosphoethanolamine transferase from Neisseria meningitidis, determined to 2.75-Å resolution. The structure reveals a previously uncharacterized helical membrane domain and a periplasmic facing soluble domain. The domains are linked by a helix that runs along the membrane surface interacting with the phospholipid head groups. Two helices located in a periplasmic loop between two transmembrane helices contain conserved charged residues and are implicated in substrate binding. Intrinsic fluorescence, limited proteolysis, and molecular dynamics studies suggest the protein may sample different conformational states to enable the binding of two very different-sized lipid substrates. These results provide insights into the mechanism of endotoxin modification and will aid a structure-guided rational drug design approach to treating multidrug-resistant bacterial infections. lipid modification | multidrug resistance | molecular dynamics | Neisseria | membrane protein structur

Neisserial LptA::His_x6 transfers PEA to lipid A of <i>E. coli</i> LPS.

<p>Lipid A profiles of LPS extracted from <i>E. coli</i> strains JCB571 expressing <i>Ec</i>DsbA (CKEC272) (Panel A), <i>E. coli</i> JCB571 expressing LptA::His_x6 (CKEC543) (Panel B) and JCB571 expressing LptA::His_x6 and <i>Ec</i>DsbA (CKEC564) (Panel C) as determined by MALDI-TOF MS. <i>bis</i>-Phosphorylated hexaacylated lipid A (m/z = 1796), the mono-phosphorylated derivative (<i>m/z</i> = 1716), and the heptaacylated version due to the addition of a palmitic acyl residue (<i>m/z</i> = 2034) were detected in all strains. <i>bis</i>-Phosphorylated tetraacylated lipid A (<i>m/z</i> = 1360) was found abundantly in the MALDI spectra of all three strains, which was likely produced from <i>bis</i>-phosphorylated hexaacylated lipid A (<i>m/z</i> = 1796) during the ionization step on MALDI. The lipid A preparations from CKEC543 expressing LptA (Panel B) and CKEC564 co-expressing LptA and <i>Ec</i>DsbA (Panel C) also contained ions consistent with one PEA added to the <i>bis</i>-phosphorylated structure (such as <i>m/z</i> 1919; i.e. 1796+123) and the heptaacylated structure (such as <i>m/z</i> = 2157, i.e. 2034+123).</p