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It is well known that neuroinflammation plays a key role in neurodegenerative diseases. Hypoxia-inducible factor (HIF) and its hydroxylases-Prolyl-4-hydroxyases (PHDs) have been found to modulate the inflammatory processes. Here, the effects of PHDs enzyme onlipopolysaccharide-induced neuroinflammation and neurocognitive deficits were investigated. BV2 microglia cells were stimulated by LPS (1 μg/ml) as neuroinflammation model in vitro. Dimethyloxalylglycine (DMOG, 100 μM) and PHD3-siRNA were used to suppress the expression of PHD3. In vivo, mice received consecutive intraperitoneal injection of LPS (500 μg/kg) for 7 days, and intraperitoneal injection of DMOG (100 mg/kg) was applied 1 h before LPS at the same days. Several neurobehavioral tests (Open field, Novel object recognition and Morris water maze) were used to measure cognitive function. RT-qPCR and Western blotting were used to investigate the expression of inflammatory cytokines, HIF-PHDs protein. Metabolic reprogramming was measured by seahorse method. The results revealed that LPS induced neuroinflammation and PHD3 expression in vivo and vitro. DMOG and PHD3knockout decreased expression of inflammatory cytokines and improved the metabolic reprogramming caused by LPS treatment. Furthermore, pretreatment of DMOG reversed learning and memory deficits in systemic LPS-exposed mice through anti-neuroinflammation, which is independent of DMOG angiogenesis. These findings suggested that PHD3 may mediate LPS-induced microglial activation and neuroinflammation-associated neurobehavioral deficits.

Postoperative cognitive dysfunction (POCD) is consistently associated with increased morbidity and mortality. However, its mechanism remains poorly understood. We hypothesized that central cholinergic neuronal degeneration facilitates the development of POCD. The impact of anesthesia/surgery (appendectomy) on learning and memory and the levels of choline acetyltransferase (ChAT), acetylcholinesterase (AChE), vesicular acetylcholine transporter (VAChT), and choline transporter (CHT) in adult and aged mice were measured. Separate cohorts were analyzed after pretreatment with donepezil, an AChE inhibitor, in aged mice or with murine-p75-saporin (mu-p75-sap), a cholinergic-specific immunotoxin, in adult mice. Morris Water Maze was used to measure the learning and memory changes after anesthesia/surgery. Western blot was used to measure the changes in the protein levels of the biomarkers of the central cholinergic system. We found that anesthesia/surgery-induced memory decline and attenuation of central cholinergic biomarkers (ChAT and VAChT) in aged mice but not in adult mice. Donepezil pretreatment reduced central cholinergic impairment in the aged mice and prevented learning and memory declines after anesthesia/surgery. In contrast, when central cholinergic neurons were pre-injured with mu-p75-sap, cognitive dysfunction developed in the adult mice after anesthesia/surgery. These data suggest that central cholinergic neuronal degeneration facilitates the development of POCD.

Background: While coronavirus disease 2019 (COVID-19) has emerged as a global pandemic, millions of COVID-19 patients have recovered and returned to their families and work, although the long-term outcomes remain unknown. Methods: This retrospective–prospective study analysed data for COVID-19 patients discharged from Leishenshan Hospital in Wuhan, China. Long-term outcomes were measured by Activity of Daily Living (ADL) Scale, Modified Medical Research Council (mMRC) Dyspnoea Scale, New York Heart Association (NYHA) classification, Self-rating Depression Scale (SDS), Carcinologic Handicap Index (CHI), and Modified Telephone Interview for Cognitive Status (TICS-M). Multivariable logistic regression was used to examine the risk factors of long-term outcomes. Findings: The follow-up period for the 464 patients was August 10–September 30, 2020. The most common sequelae were psychosocial problems (254 [57·7%]), respiratory function abnormality (149 [32·6%]), and cardiac function abnormality (98 [21·5%]). Rare sequelae were ADL disability (61 [13·3%]); pain (55 [12·5%]); feeding difficulties (54 [12·2%]); dysphonia (46 [10·4%]); and hyposmia (27 [6·1%]), as well as impairment in hearing (40 [9·1%]), vison (37 [8·4%]), swallowing (30 [6·8%]), and gustation (18 [4·1%]). Almost all patients (98·2%) had normal cognitive function. Risk factors associated with ADL disability were advanced age, intensive care unit (ICU) stay, and cancer, which were also associated with respiratory function abnormality. Risk factors associated with cardiac function abnormality were long hospital stay, cancer, and respiratory diseases. Advanced age, ICU stay, and nonischemic heart diseases were associated with psychosocial problems. Compared with female patients, male patients had decreased odds of declined respiratory, cardiac function, depression and anxiety, and pain. Interpretation: Nearly normal ADL, moderate cardiopulmonary function and psychosocial issues, and minor sensory abnormalities were observed in COVID-19 survivors. Advanced age, ICU stay, cancer, and female sex were adverse risk factors in long-term sequelae. These data provide a generalisable estimate of long-term outcomes for COVID-19. Trial Registration: This study was registered in the ClinicalTrial.gov database (NCT04508712). Funding: National Natural Science Foundation of China, Shanghai Shenkang Hospital Development Center, Shanghai municipal Education Commission, State Key Laboratoy of Neuroscience, and Renji Hospital. Declaration of Interests: All authors declare no competing interests. Ethics Approval Statement: This study was approved by the Institutional Research Ethics Committee of Renji Hospital, School of Medicine, Shanghai Jiaotong University (Ethical Committee approval number: KY2020-34). Oral consent was acquired from patients or from their immediate family members in cases of communication disorder or death.

The TNF family ligands B cell activation factor (BAFF) and a proliferation-inducing ligand (APRIL) modulate B cell function by forming homotrimers and heterotrimers. To determine the structure of a heterotrimer of BAFF and APRIL, these ligands were expressed as a single chain protein in HEK 293 cells, purified by affinity and size exclusion chromatographies, and crystallized. Crystals belonging to the orthorhombic crystal system with a space group of C2221 diffracted to 2.43 Å. Initial structural solution was obtained by the molecular replacement method, and the structure was further refined to an R factor of 0.179 and free R factor of 0.234. The atomic coordinates and structure factors have been deposited into the Protein Data Bank (accession code 4ZCH).

Highlights • Providing early ECMO support due to carbon dioxide retention and on-time decannulation may be more beneficial to patients. • The duration from tracheal intubation to ECMO cannulation was more than 7 days in some patients. • The application rules of ECMO vary in different regions.

Follicle-stimulating hormone (FSH), acting on its receptor (FSHR), plays a pivotal role in the stimulation of follicular development and maturation. Multiple injections of protein formulations are used during clinical protocols for ovulation induction and for in vitro fertilization that are followed by a selection of assisted reproductive technologies. In order to increase patient convenience and compliance several research groups have searched for orally bioavailable FSH mimetics for innovative fertility medicines. We report here the discovery of a series of substituted benzamides as positive allosteric modulators (PAM) targeting FSHR. Optimization of this series has led to enhanced activity in primary rat granulosa cells, as well as remarkable selectivity against the closely related luteinizing hormone receptor (LHR) and thyroid stimulating hormone receptor (TSHR). Two modulators, 9j and 9k, showed promising in vitro and pharmacokinetic profiles.

This article reviews the progress made in the field of glycoprotein hormones (GPH) and their receptors (GPHR) by several groups of structural biologists including ourselves aiming to gain insight into GPH signaling mechanisms. The GPH family consists of four members, with follicle-stimulating hormone (FSH) being the prototypic member. GPH members belong to the cystine-knot growth factor superfamily, and their receptors (GPHR), possessing unusually large N-terminal ectodomains, belong to the G-protein coupled receptor Family A. GPHR ectodomains can be divided into two subdomains: a high-affinity hormone binding subdomain primarily centered on the N-terminus, and a second subdomain that is located on the C-terminal region of the ectodomain that is involved in signal specificity. The two subdomains unexpectedly form an integral structure comprised of leucine-rich repeats (LRRs). Following the structure determination of hCG in 1994, the field of FSH structural biology has progressively advanced. Initially, the FSH structure was determined in partially glycosylated free form in 2001, followed by a structure of FSH bound to a truncated FSHR ectodomain in 2005, and the structure of FSH bound to the entire ectodomain in 2012. Comparisons of the structures in three forms led a proposal of a two-step monomeric receptor activation mechanism. First, binding of FSH to the FSHR high-affinity hormone-binding subdomain induces a conformational change in the hormone to form a binding pocket that is specific for a sulfated-tyrosine found as sTyr 335 in FSHR. Subsequently, the sTyr is drawn into the newly formed binding pocket, producing a lever effect on a helical pivot whereby the docking sTyr provides as the ‘pull & lift’ force. The pivot helix is flanked by rigid LRRs and locked by two disulfide bonds on both sides: the hormone-binding subdomain on one side and the last short loop before the first transmembrane helix on the other side. The lift of the sTyr loop frees the tethered extracellular loops of the 7TM domain, thereby releasing a putative inhibitory influence of the ectodomain, ultimately leading to the activating conformation of the 7TM domain. Moreover, the data lead us to propose that FSHR exists as a trimer and to present an FSHR activation mechanism consistent with the observed trimeric crystal form. A trimeric receptor provides resolution of the enigmatic, but important, biological roles played by GPH residues that are removed from the primary FSH-binding site, as well as several important GPCR phenomena, including negative cooperativity and asymmetric activation. Further reflection pursuant to this review process revealed additional novel structural characteristics such as the identification of a ‘seat’ sequence in GPH. Together with the ‘seatbelt’, the ‘seat’ enables a common heteodimeric mode of association of the common α subunit non-covalently and non-specifically with each of the three different β subunits. Moreover, it was possible to establish a dimensional order that can be used to estimate LRR curvatures. A potential binding pocket for small molecular allosteric modulators in the FSHR 7TM domain has also been identified.

We examined the role of A328(F330) in the binding of various inhibitors to cholinesterases (ChEs) using human butyrylcholinesterase (BChE) mutants to determine if the conclusions drawn from studies with acetylcholinesterase (AChE) mutants could be extended to BChE. For huperzine A and edrophonium, the results obtained with AChE mutants could be directly correlated with those obtained with native ChEs and site-specific mutants of human BChE. Inhibition studies of ethopropazine with BChE mutants, where A328 was modified to either F or Y, suggested that A328 was not solely responsible for the selectivity of ethopropazine. Volume calculations for the active-site gorge showed that the poor inhibitory activity of ethopropazine towards AChE was due to the smaller dimension of the active-site gorge. The volume of the BChE active-site gorge is approximately 200 A3 larger than that of the AChE gorge, which allows the accommodation of ethopropazine in two different orientations as demonstrated by rigid-body refinement and molecular dynamics calculations. These results suggest that, although the overall scaffolding of the two enzymes may be highly similar, the dimensions and the micro-environment of the gorge play a significant role in determining the selectivity of substrate and inhibitors for ChEs.

Planar Schlegel diagrams of fullerene cages for the reaction mechanisms between open clusters and between metals and fullerenes are used to determine the qualitative symmetry properties. The detailed Schlegel diagrams help to illustrate the subgroup symmetries of the cages that contain localized π bondings with Dewar structure bondings plus free radical π electrons, positive and negative ions, metal locations, hydrogen additions etc. Cluster interactions include C 36 H 12 , C 36 H 18 , C 24 H 12 , C 20 H 20 , C 20 H 10 . Free radical π-electrons are shown inside C 88 (D 3 ), C 82 (C 3v ), C 74 (D 3h ), C 60 (I h ), C 36 (D 3h ), C 34 (C 3v ) along with their endohedral interaction, with single metals Sc, Y, La and Lu having three top electrons s 2 d. Similarly, free-radical π-electrons are shown inside C 28 (T d ) and C 56 (T d ) along with their interaction with single metals Ti, Zr, Hf and Th having four-top electrons s 2 d 2 (plus metal U having f 3 d). The extra case of Ti@C 28 H 4 (C 3v or D 2d ) is also considered. For dimetal interactions, we consider C 84 (T d ) yielding Sc 2 @C 84 and Lu 2 @C 84 with subgroup symmetry D 2d and C 80 ( I h ) yielding Lu 2 @C 80 with subgroup symmetry D 3d . For trimetal interactions, we consider C 82 (C 3v ) yielding Sc 3 C 82 and La 3 @C 82 with subgroup symmetry C 3v and C 88 (D 3 ) yielding La 3 @C 88 with subgroup symmetry C 3 . For exohedral interactions, we consider C 30 (D 5h ) yielding LaC 29 + and C 34 (C 3v ) yielding LaC 33 + with subgroup symmetry C s .

Background: Glycoprotein hormones influence the development and function of the ovary, testis and thyroid by binding to specific high-affinity receptors. The extracellular domains of these receptors are members of the leucine-rich repeat (LRR) protein superfamily and are responsible for the high-affinity binding. The crystal structure of a glycoprotein hormone, namely human choriogonadotropin (hCG), is known, but neither the receptor structure, mode of hormone binding, nor mechanism for activation, have been established. Results Despite very low sequence similarity between exon-demarcated LRRs in the receptors and the LRRs of porcine ribonuclease inhibitor (RI), the secondary structures for the two repeat sets are found to be alike. Constraints on curvature and β -barrel geometry from the sequence pattern for repeated β α units suggest that the receptors contain three-dimensional structures similar to that of RI. With the RI crystal structure as a template, models were constructed for exons 2–8 of the receptors. The model for this portion of the choriogonadotropin receptor is complementary in shape and electrostatic characteristics to the surface of hCG at an identified focus of hormone–receptor interaction. Conclusion The predicted models for the structures and mode of hormone binding of the glycoprotein hormone receptors are to a large extent consistent with currently available biochemical and mutational data. Repeated sequences in β -barrel proteins are shown to have general implications for constraints on structure. Averaging techniques used here to recognize the structural motif in these receptors should also apply to other proteins with repeated sequences.

This work displays two-dimensional planar diagrams of three-dimensional fullerene cage clusters to clearly visualize the symmetrical arrangements of the complete number of vertices (carbon atoms), edges (bonds) and faces (carbon rings) and to search for the possible isomeric rearrangement and addition/elimination reaction mechanisms. The reactionary symmetry correlation is based on the choice of the common subgroup symmetry for the total reaction coordinate — the latter comes from the combination of multiple sets of local reaction coordinates over the periodic surface of the fullerene cage. The symmetric analysis also involves the determination of the number of symmetry-equivalent ways for such combinations to generate the total reaction coordinate. The symmetry investigation also involves the hypothetical mechanisms for the addition (and elimination) of two (diatomic) carbon atoms to (and from) the reactant fullerene cage, to be followed by subsequent cooperative cage surface rearrangements over the cyclic boundaries to reach the structural symmetry of the final-product fullerene cage. The diagrams and isomeric rearrangement mechanisms elaborated are C60(Ih, D6h, C3v, C3, D5), C76(Td, D2, C3) and C84(Td, C3, C3v). The additions and eliminations elaborated are C26(D3h) ← C28(Td) → C30(D5h), C60(Ih) → C58(C3v), and C76(D2) → C78(C2v, D3h) ← C80(D5d)b.

In order to illustrate the extension of cage cluster of given symmetry to a possible larger giant cluster of the same symmetry type, we have designed methods for drawing Schlegel (or quasi-Schlegel) diagrams that show clearly all (or almost all) the faces, vertices and edges of a three-dimensional cluster in a two-dimensional plane. The symmetries and structural details were used to select unit cells which serve as “abbreviations” for huge (fullerene) clusters, and these unit cells were then used as basis to derive mathematical principles for extending the structures up to infinitely large clusters. Possible isomers and various fullerene clusters (up to C150 of D5h symmetry) of different point-group symmetries are presented (the point groups involved for different sizes are Ih, D6d, D5d, D3d, D6h, D5h, D3h, D3, Td, C3, C3v, and D6). Simple illustrations are given to show how such clearly visible detailed structures can be used to derive the possible magic numbers of (van der Waals) clusters and to formulate the mechanism and reaction coordinates of isomeric transformations. For mixed clusters with different sets of atoms (molecules), the common (minimum) subgroup symmetry is illustrated, which can be used to determine the total structures. An example of A8B12 (e.g. Ti8C+12) is given to show the possibility of Th or D3d symmetry.

The plasma cholesteryl ester transfer protein (CETP) catalyzes the transfer of cholesteryl esters from high density lipoproteins (HDL) to triglyceride-rich lipoproteins and plays a major role in the catabolism of HDL. Lipoprotein lipase (LPL) is the rate-limiting enzyme for hydrolysis of circulating triglyceride and is involved in HDL formation. We show that tissues containing LPL are major sources of CETP mRNA in several mammalian species, including some with low cholesteryl ester transfer activity in plasma. In hamsters, adipose tissue and heart were found to be the richest sources of both CETP and LPL mRNA; in situ hybridization studies showed that the same cell types (i.e. adipocytes or myocytes) contained CETP and LPL mRNA in these tissues. Isolated adipocytes synthesized active CETP. Dietary studies revealed a complex pattern of response of CETP mRNA levels in different tissues, which showed partial similarity to the changes in LPL mRNA abundance. However, high cholesterol diets resulted in increased CETP mRNA abundance in adipose tissue, heart, and skeletal muscle, without equivalent changes in LPL mRNA. Plasma HDL cholesteryl ester levels showed strong inverse correlations with CETP mRNA abundance in adipose tissue. The results suggest a conserved function of CETP in adipose tissue and heart, such as a co-ordinate action with LPL to enhance HDL turnover. Although there is considerable overlap in the tissue- and cell-specific pattern of CETP and LPL gene expression, dietary studies revealed only limited parallelism in response at the mRNA level. The increase in CETP mRNA in peripheral tissues in response to increased dietary cholesterol suggests that local induction of CETP synthesis may help to recycle cholesterol deposited in these tissues during lipolysis of dietary lipoproteins.