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Background Coronavirus disease 2019 (COVID-19)-related short-term mortality is high in dialysis patients, but longer-term outcomes are largely unknown. We therefore assessed patient recovery in a large cohort of dialysis patients 3 months after their COVID-19 diagnosis. Methods We analyzed data on dialysis patients diagnosed with COVID-19 from 1 February 2020 to 31 March 2021 from the European Renal Association COVID-19 Database (ERACODA). The outcomes studied were patient survival, residence and functional and mental health status (estimated by their treating physician) 3 months after COVID-19 diagnosis. Complete follow-up data were available for 854 surviving patients. Patient characteristics associated with recovery were analyzed using logistic regression. Results In 2449 hemodialysis patients (mean ± SD age 67.5 ± 14.4 years, 62% male), survival probabilities at 3 months after COVID-19 diagnosis were 90% for nonhospitalized patients (n = 1087), 73% for patients admitted to the hospital but not to an intensive care unit (ICU) (n = 1165) and 40% for those admitted to an ICU (n = 197). Patient survival hardly decreased between 28 days and 3 months after COVID-19 diagnosis. At 3 months, 87% functioned at their pre-existent functional and 94% at their pre-existent mental level. Only few of the surviving patients were still admitted to the hospital (0.8–6.3%) or a nursing home (∼5%). A higher age and frailty score at presentation and ICU admission were associated with worse functional outcome. Conclusions Mortality between 28 days and 3 months after COVID-19 diagnosis was low and the majority of patients who survived COVID-19 recovered to their pre-existent functional and mental health level at 3 months after diagnosis.

Background Patients on kidney replacement therapy (KRT) are at very high risk of coronavirus disease 2019 (COVID-19). The triage pathway for KRT patients presenting to hospitals with varying severity of COVID-19 illness remains ill-defined. We studied the clinical characteristics of patients at initial and subsequent hospital presentations and the impact on patient outcomes. Methods The European Renal Association COVID-19 Database (ERACODA) was analysed for clinical and laboratory features of 1423 KRT patients with COVID-19 either hospitalized or non-hospitalized at initial triage and those re-presenting a second time. Predictors of outcomes (hospitalization, 28-day mortality) were then determined for all those not hospitalized at initial triage. Results Among 1423 KRT patients with COVID-19 [haemodialysis (HD), n = 1017; transplant, n = 406), 25% (n = 355) were not hospitalized at first presentation due to mild illness (30% HD, 13% transplant). Of the non-hospitalized patients, only 10% (n = 36) re-presented a second time, with a 5-day median interval between the two presentations (interquartile range 2–7 days). Patients who re-presented had worsening respiratory symptoms, a decrease in oxygen saturation (97% versus 90%) and an increase in C-reactive protein (26 versus 73 mg/L) and were older (72 vs 63 years) compared with those who did not return a second time. The 28-day mortality between early admission (at first presentation) and deferred admission (at second presentation) was not significantly different (29% versus 25%; P = 0.6). Older age, prior smoking history, higher clinical frailty score and self-reported shortness of breath at first presentation were identified as risk predictors of mortality when re-presenting after discharge at initial triage. Conclusions This study provides evidence that KRT patients with COVID-19 and mild illness can be managed effectively with supported outpatient care and with vigilance of respiratory symptoms, especially in those with risk factors for poor outcomes. Our findings support a risk-stratified clinical approach to admissions and discharges of KRT patients presenting with COVID-19 to aid clinical triage and optimize resource utilization during the ongoing pandemic.

The dipeptides N-carbomethoxycarbonyl-prolyl-phenylalanyl-benzyl esters (CPFs) play a significant role in the prevention of HIV-1 virus infection by interacting with the glycoprotein gp120, one of the envelope proteins of the HIV-1 virus. Of the four possible isomers of CPF, (L-pro-L-phe), (L-pro-D-phe), (D-pro-L-phe) and (D-pro-D-phe), herein denoted LL etc., the crystal structures of LL, stereoisomeric LD and the racemic mixture of LD/DL have been determined. All three peptides crystallize in the orthorhombic system and they all have similar cell dimensions: (i) LL, P2(1)2(1)2(1), a = 13.699(2), b = 25.893(5), c = 6.155(1) A, Z = 4, Dcale = 1.333 g cm-3, R = 0.070 for 1247 observed reflections; (ii) LD, P2(1)2(1)2(1), a = 11.663(2), b = 26.557(2), c = 7.281(1) A, Z = 4, Dcalc = 1.290 g cm-3, R = 0.054 for 1918 observed reflections; (iii) LD/DL, Pbc2(1), a = 11.953(2), b = 24.208(8), c = 7.782(2) A, Z = 4, Dcalc = 1.292 g cm-3, R = 0.080 for 894 observed reflections. Both the enantiomeric LD and the LD in racemic LD/DL have a similar conformation, an extended peptide chain with phi 1 = -76, -73 degrees; psi 1 = 160, 158 degrees, psi 2 = 123, 131 degrees and psi 2 = -172, -167 degrees, while peptide LL adopts a bent conformation at the Phe residue, phi 1 = -69 degrees, psi 1 = 158 degrees, phi 2 = -60 degrees and psi 2 = -34 degrees.(ABSTRACT TRUNCATED AT 250 WORDS)

The synthesis of a range of hydroxypyranones and hydroxypyridinones with potential for the chelation of indium(III) is described. The crystal structures of two of the indium complexes are presented. The distribution coefficients of the ligands and the corresponding iron(III), gallium(III), and indium(III) complexes are reported. Good linear relationships between the distribution coefficients of the iron and gallium complexes and iron and indium complexes were obtained. In contrast a nonlinear relationship was obtained between the distribution coefficient of the free ligand and the distribution coefficient of the three groups of complexes. This latter relationship was used to identify compounds with optimal cell labeling properties. Two such compounds both 6-(alkoxymethyl)-3-hydroxy-4H-pyran-4-ones have been compared with tropolone for their ability to label human leucocytes with 111In. The leucocyte labeling efficiencies of the selected ligands were greater and the in-vitro plasma stabilities were similar to that of 111In-tropolonate. These results suggest that the new bidentate ligands may offer advantages over those currently used for cell-labeling.

Seven new briariane diterpene lactones were isolated from the gorgonian Solenopodium excavatum collected in New Guinea. One structure (4) was determined by X-ray diffraction and the remainder were elucidated by spectroscopic analysis. Six of the new briareolides, 4-9, exist in a conformation that is quite uncommon for representatives of this fairly large family of compounds, namely one in which the bonds joining the 10-membered ring to the 6-membered ring are nearly diaxially oriented. Conformational energy calculations are discussed as are the structural features that are responsible for the uncommon conformation. Mild cytotoxic activity was confirmed for 4.

Two new substituted dibenzo-p-dioxins, aplidioxins A (1) and B (2), were isolated from the ascidian Aplidiopsis ocellata. The structures of these compounds were elucidated by a combination of 1D and 2D NMR spectroscopy and an X-ray analysis of aplidioxin A.

When Pseudomonas putida ATCC 39167 and plant-deleterious Pseudomonas fluorescens A225 were grown in an iron-deficient culture medium, they each produced two different novel yellow-green fluorescent pseudobactins: P39167-I, II and PA225-I, II. Pseudobactin P39167-I has a molecular formula of C46H65O23N13 and is monoanionic at neutral pH. P39167-II has the molecular formula of C46H63O22N13 and no charge at neutral pH. Pseudobactin PA225-I has a molecular formula of C46H65O24N13 and is monoanionic at neutral pH whereas pseudobactin PA225-II has the molecular formula of C46H63O23N13 and no charge at neutral pH. All four of the pseudobactins contain a dihydroxyquinoline-based chromophore. The amino acid sequence for the octapeptide in case of pseudobactins from P. putida ATCC 39167 is Chr-Ser(1)-Ala(1)-AcOHOrn-Gly-Ala(2)-OHAsp-Ser(2)-Thr. In case of pseudobactins from P. fluorescens A225, the octapeptide has the sequence Chr-Ser(1)-Ala-AcOHOrn-Gly-Ser(2)-OHAsp-Ser(3)-Thr. For all four pseudobactins (P39167-I, II and PA225-I, II), the serine(1) residue of the octapeptide is attached to the carboxylic acid group on the C-11 of the fluorescent quinoline via an amide bond. Additionally, for pseudobactin P39167-II and PA225-II, the hydroxyl group of the serine(1) residue is also attached to the carboxyl group of threonine residue at the carboxy terminus of the peptide via an ester bond, resulting in a cyclic depsipeptide in contrast to the linear peptide chain of P39167-I and PA225-I. For all four pseudobactins, a malamide group is attached to the C-3 of the quinoline derived chromophore. The three bidentate iron(III) chelating groups in all four pseudobactins consist of a 1,2-dihydroxy aromatic group of the fluorescent chromophore, a hydroxy acid group of beta-hydroxy aspartic acid, and a hydroxamate group from the acylated Ndelta-hydroxyornithine. The amino acid constituents of the pseudobactins P39167 I, II are the same as those in pseudobactin A214, whereas those in A225 I, II are the same as in 7SR1, but in both cases the sequences are different. The uptake results indicate a single outer membrane receptor protein for ferric-pseudobactins in both organisms. The receptor proteins in the two species are similar but not identical.

Fast protein liquid chromatography (FPLC) with DEAE-Sepharose Fast Flow, PBE-94 and Q-Sepharose Fast Flow columns are applied to the purification of the ferric enterobactin protein receptor (FepA). The apparent single band of FepA on SDS-PAGE is isolated and purified into two proteins with very similar molecular weights. The two proteins are identified to be FepA and ferric citrate protein receptor (FecA) by N-terminus amino acid determination and a computer search with the Gene Bank file. The assay of binding activities of these proteins shows that both FepA and FecA bind ferric enterobactin, with the former having about double the activity of the latter. Competition studies shows that Fe-MECAM is competitively bound to both proteins and that ferric parabactin only slightly competes with [55Fe]ferric enterobactin. It is found that ferrichrome A has no effect on the binding of the receptor proteins with ferric enterobactin.

In our earlier paper, it was demonstrated that the FecA receptor protein from Escherichia coli UT5600/pBB2 (leu −, proC −, trpE −, entA −, rpsl −, Δ(ompT-fepA)−/Ampr, fepA) binds with ferric enterobactin. In order to explore this further the outer membrane receptor protein, FecA, has been isolated from UT5600 (fepA −) and purified to homogeneity by DE-52-cellulose anion exchange chromatography followed by MonoPFPLC chromatofocusing. Partially purified FecA and homogeneous FecA show binding activity to [55Fe]ferric enterobactin and the binding is specific. Binding activity of FecA can be enhanced by ferric citrate. Lipopolysaccharide-free FecA as ascertained by silver staining and the endotoxin test still retains the same activity. In vivo uptake studies using different strains of E. coli suggest that FecA in E. coli plays an important role in ferrienterobactin transport.