On-Surface Isomerization of Indigo within 1D Coordination Polymers.

Natural products are attractive components to tailor environmentally friendly advanced new materials. We present surface-confined metallosupramolecular engineering of coordination polymers using natural dyes as molecular building blocks: indigo and the related Tyrian purple. Both building blocks yield identical, well-defined coordination polymers composed of (1 dehydroindigo : 1 Fe) repeat units on two different silver single crystal surfaces. These polymers are characterized atomically by submolecular resolution scanning tunnelling microscopy, bond-resolving atomic force microscopy and X-ray photoelectron spectroscopy. On Ag(100) and on Ag(111), the trans configuration of dehydroindigo results in N,O-chelation in the polymer chains. On the more inert Ag(111) surface, the molecules additionally undergo thermally induced isomerization from the trans to the cis configuration and afford N,N- plus O,O-chelation. Density functional theory calculations confirm that the coordination polymers of the cis-isomers on Ag(111) and of the trans-isomers on Ag(100) are energetically favoured. Our results demonstrate post-synthetic linker isomerization in interfacial metal-organic nanosystems.

Treatment Outcome with High versus low-to-moderate Dosing of Corticosteroids in Early vis-a-vis Late-onset Hypoxic Cases of COVID-19: A Multicentric Retrospective Cohort Study.

Background: Corticosteroid dosing in COVID-19 cases associated with early-onset and late-onset hypoxia have not been separately explored. Methods: In this retrospective cohort study, we divided hypoxic COVID-19 cases into groups based on timing of initiation of corticosteroids relative to onset of symptoms; Group A (≤6th day), Group B (7th-9th day) and Group C (≥10th day), each group being sub-grouped into high and low-to-moderate dose corticosteroid recipients. Cox regression with propensity scoring was used to compare 28-day mortality between high and low-to-moderate dose recipients separately in Group A, Group B, Group C. Results: Among 505 patients included, propensity score matched Cox regression showed greater risk of all-cause mortality among high dose recipients in Group A [HR= 7.35, 95%CI 3.36-16.11, p-value<0·01, N=114] and Group B [HR=3.17, 95%CI 1.65-6.07, p-value<0·01, N=251]. In Group C, mortality was lowest [12.8% (18/140)] with no significant difference between sub-groups [HR=2.52, 95%CI 0.22-29.15, p-value=0.459, N=140]. Kruskal-Wallis Test between Group A, Group B and Group C for six pre-defined exposure variables showed significant differences for Neutrophil:Lymphocyte Ratio (NLR). Conclusion: When steroids were initiated early (owing to an earlier onset of hypoxic symptoms), a high dose of corticosteroid was associated with greater overall 28-day mortality compared to a low-to-moderate dose. NLR, a marker for individual immune response, varied between treatment groups.

A 31-year-old female patient with chronic kidney disease presenting with persistent cough.

Can you diagnose this 31-year-old woman with end-stage renal disease and a persistent cough? https://bit.ly/3s7n5VU.

Systemic lupus erythematosus presenting as right-sided massive pleural effusion with autoimmune hypothyroidism and medium vessel vasculopathy.

Segmental involvement of medium-sized vessels are lesser-known manifestations of systemic lupus erythematosus (SLE) vasculopathy. Medium vessel vasculopathy and peripheral vascular disease (PVD) mimicking manifestations of SLE, although rare, have been reported, particularly in Asian women mostly under the age of 30 years. This is due to metabolic disadvantages in their ethnicity, with high incidence of insulin resistance and resulting metabolic syndrome, leading to lower high-density lipoprotein cholesterol levels, higher triglyceride levels and small dense low-density lipoprotein, increased proinflammatory cytokines, endothelial dysfunction and procoagulant tendency. Owing to the longer duration of the disease with the simultaneous use of steroids, vessels are often affected. SLE may also present with thyroid manifestations against a background of a proinflammatory immune state, where autoimmune thyroid diseases, such as Hashimoto's thyroiditis, may coexist. Here, we describe the case of a young woman who presented with progressive shortness of breath, right leg pain and cough with amenorrhoea and was diagnosed with SLE.