Relationships among tumor necrosis factor-alpha levels, beta-amyloid accumulation, and hippocampal atrophy in patients with late-life major depressive disorder.

BACKGROUND: Major depressive disorder (MDD) is characterized by hippocampal volume reduction, impacting cognitive function. Inflammation, particularly elevated tumor necrosis factor-alpha (TNF-α) levels, is consistently implicated in MDD pathophysiology. This study investigates the relationships between TNF-α levels, hippocampal volume, beta-amyloid (Aß) burden, and cognitive abilities in MDD patients, aiming to illuminate the complex interplay among inflammatory markers, pathology indicators, structural brain alterations, and cognitive performance in non-demented MDD individuals. METHOD: Fifty-two non-demented MDD patients, comprising 25 with mild cognitive impairment (MCI), were recruited along with 10 control subjects. Each participant underwent a thorough assessment encompassing TNF-α blood testing, 18F-florbetapir positron emission tomography, magnetic resonance imaging scans, and neuropsychological testing. Statistical analyses, adjusted for age and education, were performed to investigate the associations between TNF-α levels, adjusted hippocampal volume (HVa), global Aß burden, and cognitive performance. RESULTS: MCI MDD patients displayed elevated TNF-α levels and reduced HVa relative to controls. Correlation analyses demonstrated inverse relationships between TNF-α level and HVa in MCI MDD, all MDD, and all subjects groups. Both TNF-α level and HVa exhibited significant correlations with processing speed across all MDD and all subjects. Notably, global 18F-florbetapir standardized uptake value ratio did not exhibit significant correlations with TNF-α level, HVa, and cognitive measures. CONCLUSION: This study highlights elevated TNF-α levels and reduced hippocampal volume in MCI MDD patients, indicating a potential association between peripheral inflammation and structural brain alterations in depression. Furthermore, our results suggest that certain cases of MDD may be affected by non-amyloid-mediated process, which impacts their TNF-α and hippocampal volume. These findings emphasize the importance of further investigating the complex interplay among inflammation, neurodegeneration, and cognitive function in MDD.

Grouting technique-combining transvenous Onyx and coils for the embolization of complex non-cavernous intracranial dural arteriovenous fistulas.

Objective: Incomplete occlusion of cerebral dural arteriovenous fistula (DAVF) may lead to fistula recurrence and rebleeding, which may necessitate several embolizations and lead to worse clinical outcomes. Herein, we describe a grouting technique for endovascular embolization and its outcomes in a series of patients with complex intracranial DAVF. Methods: A total of 20 patients with aggressive type or symptomatic intracranial non-cavernous DAVF underwent endovascular transvenous embolization combining detachable coils and Onyx. Two microcatheters were positioned either in the distal segment of the involved sinus or near the draining veins. To achieve tight occlusion of the involved sinus, coils were carefully delivered through the first microcatheter, starting from the distal segment and then to the proximal segment. Next, Onyx was injected through the second microcatheter to reinforce and fill (grout) the interspace of coil mass and gradually refluxed to the mural channels and para-sinus cortical veins until the fistula was completely occluded. Results: Successful embolization was achieved in all 20 patients. The initial angiographic results revealed the achievement of complete occlusion in 19 patients (95%). At the postembolization follow-up, complete obliteration of the fistula was achieved in all patients (100%). No symptom or angiographic recurrence was observed at the 2- to 5-year follow-ups. No patient required additional embolization or stereotactic radiosurgery. Conclusion: The proposed grouting technique combining detachable coils and Onyx appears to be promising for the elimination of complex intracranial non-cavernous DAVFs.

Treatment outcome of bridge mechanical thrombectomy with different IV-tPA dosages in the standard and extended time window in real-world practice.

BACKGROUND: Differences of treatment outcome between full or reduced dose of tissue plasminogen activator (tPA) for bridge mechanical thrombectomy (MT) in the extended time window have not been clearly established. We aimed to present real-world results of bridge MT with different tPA dosages in the standard and extended windows. MATERIALS AND METHODS: Patients with anterior circulation stroke treated with MT between 2017 and 2021 at two stroke referral centers were retrospectively reviewed. Bridge MT with tPA were categorized as full (0.9 mg/kg) or reduced (<0.9 mg/kg) dose. Standard window (SW) cohort was defined as MT performed within 6 h of acute ischemic stroke onset, while those beyond 6 h as the extended window (EW) cohort. 90 days Modified Rankin Scale (mRS) score, technical treatment success, in-hospital mortality, and post-treatment hemorrhage were analyzed. RESULTS: A total of 423 patients met the inclusion criteria, 218 of which treated in the SW, while 205 treated in the EW. Within the SW cohort, the full-dose tPA group demonstrated a higher proportion of good functional outcome (GFO) at 90 days (mRS0-3) versus reduced (49% vs 21%, p = 0.0358). The overall GFO of SW was higher than that of the EW cohort (33% vs 20%, p = 0.0480). Within the EW cohort, GFO was similar between full and reduced dose groups. Successful reperfusion rate was lower in SW versus EW cohorts (39% vs 58%, p = 0.0199). CONCLUSION: In real-world practice, the GFO of bridge MT is better than MT alone. The tPA dosage is not a determining factor of GFO in EW MT.

Gustatory receptor 11 is involved in detecting the oviposition water of Asian tiger mosquito, Aedes albopictus.

BACKGROUND: Aedes albopictus is a major arbovirus vector with small stagnant water containers being its oviposition sites. Mosquitoes search for these sites based on their olfactory cues (odor and moisture emanating from the water at the oviposition site), visual cues (size and color of the site), and gustatory cues (ion and nutrient concentration in that water). The gustatory mechanism through which mosquitoes search for oviposition sites remains unknown. METHODS: To investigate the role of taste receptors in Ae. albopictus oviposition site selection, we developed a laboratory model. This model assessed mosquito behavior in locating and detecting oviposition sites, using a location index to quantify site preference and detection time to measure response to water presence. We compared oviposition site-searching efficiency between mosquitoes with blocked and unblocked appendages, targeting the taste organs. Transcriptome sequencing was conducted to identify differentially expressed genes between water-exposed and unexposed mosquitoes. CRISPR/Cas9 technology was then employed to generate a mutant strain with a targeted gene knockout. RESULTS: There was no significant difference between the blocked and unblocked groups in the location index. In contrast, the detection time of the unblocked group differed significantly from all other groups, including those with blocked foreleg tarsus, midleg tarsus, hindleg tarsus, all tibia, and all tarsus. Transcriptome sequencing analyses of water-exposed and unexposed mosquitoes revealed that the taste-related gene gustatory receptor 11(gr11) was differentially expressed. This gene was knocked out with CRISPR/Cas9 technology to generate a pure mutant strain with 2- and 4-bp deletions, which exhibited a significantly longer detection time than the wild-type strain. CONCLUSIONS: This study reveals the role of Ae. albopictus gr11 in water detection at oviposition sites, thereby providing a theoretical basis and scientific guidelines for managing the breeding sites of these mosquitoes.

Incidental Findings in Lung Cancer Screening.

While low-dose computed tomography (LDCT) for lung cancer screening (LCS) has been recognized for its effectiveness in reducing lung cancer mortality, it often simultaneously leads to the detection of incidental findings (IFs) unrelated to the primary screening indication. These IFs present diagnostic and management challenges, potentially causing unnecessary anxiety and further invasive diagnostic procedures for patients. This review article provides an overview of IFs encountered in LDCT, emphasizing their clinical significance and recommended management strategies. We categorize IFs based on their anatomical locations (intrathoracic-intrapulmonary, intrathoracic-extrapulmonary, and extrathoracic) and discuss the most common findings. We highlight the importance of utilizing guidelines and standardized reporting systems by the American College of Radiology (ACR) to guide appropriate follow-ups. For each category, we present specific IF examples, their radiologic features, and the suggested management approach. This review aims to provide radiologists and clinicians with a comprehensive understanding of IFs in LCS for accurate assessment and management, ultimately enhancing patient care. Finally, we outline a few key aspects for future research and development in managing IFs.

Pollen identification of three notorious illicit drug plants and its potential applications in forensic practice.

Opium poppy, coca and cannabis are raw materials for three notorious illicit drugs. For a long time, drug lords have been growing and smuggling these drugs in a variety of ways and channels and are continually finding new ways of trafficking their wares, which has led to the increasing difficulty of global drug enforcement. In the present paper, we propose an innovative pollen identification system for these important drug plants, which provides a tool for screening and detection of the drugs to aid in drug enforcement. By utilizing the characteristics of these fine particles, their abundant production, and high resistance to decay, we believe this tool could be applied in the following scenarios: detecting and dynamically monitoring drug cultivation activities; determining whether a suspect has been to fields of drug plants and determining whether the site has ever been planted with a drug plant and/or was involved in drug production. In the future, combined with microscope automatic image acquisition technology and intelligent image recognition technology, this pollen identification system is expected to be used to screen three notorious illicit drug plants, thus enhancing the efficiency of drug related crime investigations.

Tandem Sulfonylative Annulation/Halogenation of 1,7-Enynes with Sodium Sulfinate and TBAX for the Assembly of 4-Methylenechromanes.

An effective and stereoselective synthesis of halogenated (E)-4-methylenechromanes with a sulfonyl group was developed via the copper-catalyzed sulfonylative annulation/halogenation of 1,7-enynes, in which sodium sulfinates were used as the sulfonyl reagents and tetrabutylammonium halide provided the halogen sources. The formed alkenyl C-X bonds were valuable and can efficiently undergo the subsequent hydrolysis, alkenylation, alkynylation, arylation, alkylthiolation, and alkoxylation to furnish a series of highly functionalized 4-methylenechromanes.

Sclerotherapy with intralesional bleomycin injection under guidance of multi-slice CT for retrobulbar orbital low-flow vascular lesions-single-center experience.

OBJECTIVE: This study investigated the safety and efficacy of sclerotherapy with intralesional bleomycin injection (IBI) for retrobulbar orbital low-flow vascular lesions under multi-slice computed tomography (CT) guidance. METHODS: Between January 2010 and September 2021, consecutive patients with retrobulbar orbital low-flow vascular lesions who underwent CT-guided IBI at a tertiary centre in Taiwan were enrolled. Their medical records and imaging data were retrospectively collected. RESULTS: This study enrolled 13 patients (7 male and 6 female patients; age range: 1-57 years; mean age: 25.9 years) with lymphatic malformation (LM, n = 4), venolymphatic malformation (n = 1), and venous malformation (VM, n = 8). The overall radiological response rate was 76.9% (10 of 13); the radiological response rate was 75.0% in the VM group (6 of 8) and 75.0% in the LM group (3 of 4). Moreover, 3 patients (23.1%) had minor complications and 1 (7.7%) had a major complication. The mean clinical and radiological follow-up was 8.3 months and no recurrence or progression was reported. CONCLUSION: CT-guided IBI is an effective and relatively safe minimally invasive treatment for retrobulbar orbital low-flow vascular lesions, with an overall radiological response rate of 76.9% in a mean of 1.5 sessions and a low complication rate. ADVANCES IN KNOWLEDGE: CT-guided sclerotherapy with IBI is a relatively safe, effective, and feasible alternative treatment option for retrobulbar orbital low-flow vascular lesions.

A fixel-based analysis of white matter reductions early detects Parkinson disease with mild cognitive impairment.

BACKGROUND: White matter (WM) tract alterations are early signs of cognitive impairment in Parkinson disease (PD) patients. Fixel-based analysis (FBA) has advantages over traditional diffusion tensor imaging in managing complex and crossing fibers. We used FBA to measure fiber-specific changes in patients with PD mild cognitive impairment (PD-MCI) and PD normal cognition (PD-NC). METHODS: Seventy-one patients with PD without dementia were included: 39 PD-MCI and 32 PD-NC. All underwent diffusion-weighted imaging, clinical examinations, and tests to evaluate their cognitive function globally and in five cognitive domains. FBA was used to investigate fiber-tract alterations and compare PD-MCI with PD-NC subjects. Correlations with each cognitive test were analyzed. RESULTS: Patients with PD-MCI were significantly older (P = 0.044), had a higher male-to-female ratio (P = 0.006) and total Unified Parkinson's Disease Rating Scale score (P = 0.001). All fixel-based metrics were significantly reduced within the body of the corpus callosum and superior corona radiata in PD-MCI patients (family-wise error-corrected P value < 0.05) compared with PD-NC patients. The cingulum, superior longitudinal fasciculi, and thalamocortical circuit exhibited predominantly fiber-bundle cross-section (FC) changes. In regression analysis, reduced FC values in cerebellar circuits were associated with poor motor function in PD-MCI patients and poor picture-naming ability in PD-NC patients. CONCLUSIONS: PD-MCI patients have significant WM alterations compared with PD-NC patients. FBA revealed these changes in various bundle tracts, helping us to better understand specific WM changes that are functionally implicated in PD cognitive decline. FBA is potentially useful in detecting early cognitive decline in PD.

High diet quality indices associated with lower risk of lipid profile abnormalities in Taiwanese kidney transplant recipients.

Cardiovascular disease (CVD) and its risk factors seem to be linked with deteriorated graft function and persists as the major cause of mortality in kidney transplant recipients (KTRs). Diet quality is associated with CVD prevention in the healthy population, however, less study focuses on KTRs. The study aimed to determine the association between diet quality indices and lipid profile abnormalities as risk factors for CVD in KTRs. This prospective study enrolled 106 KTRs who had functioning allografts from September 2016. Lipid profiles included low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglyceride (TG) and were based on the National Cholesterol Education Program Adult Treatment Panel III recommendations. Three-day dietary data were collected by a well-trained registered dietitian. The Alternative Healthy Eating Index-Taiwan (AHEI-Taiwan), Alternative Healthy Eating Index-2010 (AHEI-2010), and Healthy Eating Index-2015 (HEI-2015) scores were calculated and divided into quartiles and compared accordingly. KTRs' mean LDL-C, HDL-C, TC, and TG levels were 119.8 ± 36.6 mg/dL, 52.0 ± 17.9 mg/dL, 205.8 ± 43.9 mg/dL, and 160.2 ± 121.6 mg/dL, respectively. Compared with the lowest quartile, only the highest quartile of AHEI-Taiwan had lower TC and LDL-C levels. After adjustment for age, gender, energy, Charlson comorbidity index, transplant duration, and dialysis duration, logistic regression analysis revealed that the highest quartile of AHEI-Taiwan had 82% (odds ratio [OR], 0.18; 95% confidence interval [CI] 0.04-0.72, p < 0.05) lower odds of high TC and 88% (OR 0.12; 95% CI 0.03-0.58, p < 0.05) lower odds of high LDL-C, and the highest quartile of HEI-2015 had 77% (OR 0.23; 95% CI 0.05-0.95, p < 0.05) lower odds of high LDL-C. Higher adherence to a healthy diet as per AHEI-Taiwan and HEI-2015 guidelines associated with lower risk of lipid profile abnormalities in KTRs.

Association of Three Different Dietary Approaches to Stop Hypertension Diet Indices with Renal Function in Renal Transplant Recipients.

Several dietary indices assess the impacts of the Dietary Approaches to Stop Hypertension (DASH) diet on health outcomes. We explored DASH adherence and renal function among 85 Taiwanese renal transplant recipients (RTRs) in a cross-sectional study. Data collection included demographics, routine laboratory data, and 3-day dietary records. Three separate DASH indices, that defined by Camões (based on nine nutrients), that defined by Fung (using seven food groups and sodium), and that modified by Fung (as above but separated for men and women) were used. Renal function was ascertained through the estimated glomerular filtration rate (eGFR) from patients' medical records. Participants' mean age was 49.7 ± 12.6 years and eGFR was 54.71 ± 21.48 mL/min/1.73 m2. The three established DASH diet indices displayed significant correlations (r = 0.50-0.91) and indicated the nutritional adequacy of the diet. Multiple linear regressions indicated a significant positive association between higher DASH scores for each index and increased eGFR. In addition, RTRs in the highest DASH score tertile had higher eGFR rates than those in the lowest tertile, regardless of confounding variables. Adherence to a DASH-style diet correlated with better renal function among RTRs. Educating RTRs about the DASH diet may prevent graft function deterioration.

Comparing transvenous coiling and transarterial embolization with Onyx/NBCA for cavernous sinus dural arteriovenous fistulas: a retrospective study in a single center.

BACKGROUND: Endovascular management is the gold standard for cavernous sinus dural arteriovenous fistulas (CS-dAVFs) in patients with signs of ophthalmoplegia, visual defects, or intolerable clinical symptoms. Although the efficacy of embolization has been confirmed, complications during post-endovascular management have not been compared in a more extensive CS-dAVFs case series. Therefore, we compared the effectiveness and peri-procedural complications of transvenous coiling with those of transarterial embolization (TAE) using liquid embolic agents. MATERIAL AND METHODS: We reviewed 71 patients with CS-dAVFs in one medical center from 2005/7 to 2016/7. We performed seventy-seven procedures on 71 patients, including six recurrent cases. We compared the efficacy and peri-procedural complications of transvenous coiling and TAE. RESULTS: The complete occlusion rate for transvenous coiling was 79.2%, and that for TAE was 75.0%. Findings revealed (1) similar ophthalmoplegia complication rates (p = 0.744); (2) more frequent and permanent CN5 or CN7 neuropathy with liquid embolic agent use (p = 0.031 and 0.028, respectively); and (3) a higher risk of infarction or ICH (p =0.002 and 0.028, respectively) in response to aggressive TAE. CONCLUSION: Transvenous cavernous sinus coiling resulted in a similar occlusion rate and lower complication risk than transarterial Onyx/n-butyl cyanoacrylate (NBCA). We can access via an occluded inferior petrosal sinus (even contralateral), and direct transorbital puncture was a safe alternative. TAE with Onyx/NBCA was helpful in cases of oligo-feeders, but multidisciplinary treatment and multi-session TAE were usually needed for patients with multiple feeders and complex fistulas.

Emergence of the Chern Supermetal and Pair-Density Wave through Higher-Order Van Hove Singularities in the Haldane-Hubbard Model.

While advances in electronic band theory have brought to light new topological systems, understanding the interplay of band topology and electronic interactions remains a frontier question. In this work, we predict new interacting electronic orders emerging near higher-order Van Hove singularities present in the Chern bands of the Haldane model. We classify the nature of such singularities and employ unbiased renormalization group methods that unveil a complex landscape of electronic orders, which include ferromagnetism, density waves, and superconductivity. Importantly, we show that repulsive interactions can stabilize the long-sought pair-density-wave state and an exotic Chern supermetal, which is a new class of non-Fermi liquid with anomalous quantum Hall response. This framework opens a new path to explore unconventional electronic phases in two-dimensional chiral bands through the interplay of band topology and higher-order Van Hove singularities.

Long-term outcomes of coils embolization for superior hypophyseal artery aneurysms.

Objective: Superior hypophyseal artery (SHA) aneurysms are intradural, and their rupture can result in subarachnoid hemorrhage. Considering the related surgical difficulty and anatomical restrictions, endovascular treatment (EVT) is considered the most favorable modality for SHA aneurysms; however, the long-term outcomes of EVT have rarely been reported. The study assessed the incidence of and risk factors for recurrence of SHA aneurysms after EVT as well as the correlation factors for SHA aneurysm rupture. Methods: We included 112 patients with SHA aneurysms treated with EVT at our facility between 2009 and 2020. Here, EVT included non-stent-assisted (simple or balloon-assisted) or stent-assisted coiling. Flow diverter was not included because it was barely used due to its high cost under our national insurance's limitation, and a high proportion of ruptured aneurysms in our series. Univariate and multivariate logistic regression was performed to evaluate the correlation factors for SHA aneurysm rupture, along with the incidence of and risk factors for post-EVT SHA aneurysm recurrence and re-treatment. Results: In our patients, the mean angiographic follow-up period was 3.12 years. The presence of type IA or IB cavernous internal carotid artery (cICA) was strongly correlated with SHA aneurysm rupture. Recurrence occurred in 17 (13.4%) patients, of which only 1 (1.4%) patient had received stent-assisted coiling. All cases of recurrence were observed within 2 years after EVT. The multivariate logistic regression results showed that ruptured aneurysm and non-stent-assisted coiling were independent risk factors for aneurysm recurrence. Of the 17 cases of aneurysm recurrence, 9 (52.9%) received re-treatment. Moreover, aneurysm rupture was the only factor significantly correlated with re-treatment in multivariate logistic regression. No re-recurrence was observed when a recurrent aneurysm was treated with stent-assisted coiling. Conclusion: Type I cICA was common factor for aneurysm rupture. Although flow-diverter treatment serves as another suitable technique that was not compared with, coils embolization was effective treatment modality for SHA aneurysms, leading to low recurrence and complication rates, especially with stent use. All cases of recurrence occurred within 2 years after EVT; they were strongly associated with prior aneurysm rupture. Further stent-assisted coiling was noticed to prevent re-recurrence.

[Acupuncture at "umbilical four-acupoints" for chronic insomnia and its comorbid symptoms].

OBJECTIVE: To observe the effects of acupuncture at "umbilical four-acupoints" on chronic insomnia and its comorbid symptoms. METHODS: A total of 120 patients with chronic insomnia were randomly divided into an observation group (60 cases, 8 cases dropped off) and a control group (60 cases, 5 cases dropped off). The patients in the observation group were treated with acupuncture at regular acupoints (Baihui [GV 20] and bilateral Shenmen [HT 7], Neiguan [PC 6], Anmian [Extra]) and "umbilical four-acupoints", while the patients in the control group were treated with acupuncture at regular acupoints. Acupuncture was given once a day, 6 times a week, for a total of 3 weeks in the two groups. The Pittsburgh sleep quality index (PSQI), insomnia severity index (ISI) scores were observed before treatment, after treatment and in follow-up of one month after treatment completion; the Beck anxiety inventory (BAI), Beck depression inventory (BDI), fatigue severity scale (FSS), and Epworth sleepiness scale (ESS) scores were observed before and after treatment; the sleep parameters of polysomnography (PSG), including sleep latency (SL), awake-up time (AT), sleep efficiency (SE) and total sleep time (TST), were observed before and after treatment using polysomnography monitor in the two groups. RESULTS: Compared with those before treatment, the PSQI and ISI scores in both groups were reduced after treatment and in follow-up (P<0.05), and the PSQI and ISI scores in the observation group were lower than those in the control group after treatment and in follow-up (P<0.05). Compared with those before treatment, the BAI, BDI, FSS and ESS scores in both groups were reduced after treatment (P<0.05), and the BAI, BDI, FSS and ESS scores in the observation group were lower than those in the control group after treatment (P<0.05). Compared with those before treatment, the SL and AT in both groups were reduced after treatment (P<0.05), while SE and TST were increased after treatment (P<0.05); after treatment, the SL and AT in the observation group were lower than those in the control group (P<0.05), while SE and TST in the observation group were higher than those in the control group (P<0.05). CONCLUSION: On the basis of regular acupoint selection, acupuncture at "umbilical four-acupoints" could improve sleep quality, alleviate the severity of insomnia, and improve the comorbid symptoms i.e. anxiety, depression, fatigue and lethargy in patients with chronic insomnia.

High Alternative Health Eating Index-Taiwan Scores Are Associated With Prevention of Graft Dysfunction in Taiwanese Renal Transplant Recipients.

BACKGROUND: Various dietary quality indices demonstrate that a higher dietary quality score is associated with a reduced risk of several chronic diseases. However, creating an index tailored to the national population is crucial. The study investigated the association between the Alternative Healthy Eating Index-Taiwan (AHEI-Taiwan) and graft dysfunction in Taiwanese renal transplant recipients (RTRs). METHODS: A prospective cohort study recruited 102 RTRs with a functioning allograft without acute rejection in the last 3 months from September 2016 to June 2018. Laboratory data were obtained from the medical records of patients. Graft dysfunction was indicated by an estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m2 in accordance with the Kidney Disease Outcomes Quality Initiative guideline. The dietary quality index AHEI-Taiwan was adapted from the AHEI based on Taiwanese dietary recommendations. RESULTS: Mean age, renal transplant time, and eGFR were 48.9 ± 12.8 years, 8.5 ± 5.8 years, and 54.9 ± 17.8 mL/min per 1.73 m2, respectively, in 102 RTRs. The RTRs with the highest quartile of AHEI-Taiwan scores were older and had a higher eGFR. Logistic regression analysis adjusted for age, sex, calories, Charlson comorbidity index, transplant time, and dialysis time showed that the highest quartile of the AHEI-Taiwan was associated with an 88% (odds ratio, 0.12; 95% CI, 0.03-0.59, P < .01) lower risk of graft dysfunction. CONCLUSION: A high AHEI-Taiwan score was associated with a reduced risk of graft dysfunction in Taiwanese RTRs.

Pair-Density-Wave and Chiral Superconductivity in Twisted Bilayer Transition Metal Dichalcogenides.

We theoretically explore possible orders induced by weak repulsive interactions in twisted bilayer transition metal dichalcogenides (e.g., WSe_{2}) in the presence of an out-of-plane electric field. Using renormalization group analysis, we show that superconductivity survives even with the conventional van Hove singularities. We find that topological chiral superconducting states with Chern number N=1, 2, 4 (namely, p+ip, d+id, and g+ig) appear over a large parameter region with a moiré filling factor around n=1. At some special values of applied electric field and in the presence of a weak out-of-plane Zeeman field, spin-polarized pair-density-wave (PDW) superconductivity can emerge. This spin-polarized PDW state can be probed by experiments such as spin-polarized STM measuring spin-resolved pairing gap and quasiparticle interference. Moreover, the spin-polarized PDW could lead to a spin-polarized superconducting diode effect.

Cryo-EM reveals the structure and dynamics of a 723-residue malate synthase G.

Determination of sub-100 kDa (kDa) structures by cryo-electron microscopy (EM) is a longstanding but not straightforward goal. Here, we present a 2.9-Å cryo-EM structure of a 723-amino acid apo-form malate synthase G (MSG) from Escherichia coli. The cryo-EM structure of the 82-kDa MSG exhibits the same global folding as structures resolved by crystallography and nuclear magnetic resonance (NMR) spectroscopy, and the crystal and cryo-EM structures are indistinguishable. Analyses of MSG dynamics reveal consistent conformational flexibilities among the three experimental approaches, most notably that the α/ß domain exhibits structural heterogeneity. We observed that sidechains of F453, L454, M629, and E630 residues involved in hosting the cofactor acetyl-CoA and substrate rotate differently between the cryo-EM apo-form and complex crystal structures. Our work demonstrates that the cryo-EM technique can be used to determine structures and conformational heterogeneity of sub-100 kDa biomolecules to a quality as high as that obtained from X-ray crystallography and NMR spectroscopy.

Atrophy, hypometabolism and implication regarding pathology in late-life major depression with suspected non-alzheimer pathophysiology (SNAP).

BACKGROUND: A substantial proportion of individuals with late-life major depression could be classified as having a suspected non-Alzheimer disease pathophysiology (SNAP), as indicated by a negative test for the biomarker ß-amyloid (Aß-) but a positive test for neurodegeneration (ND+). This study investigated the clinical features, characteristic patterns of brain atrophy and hypometabolism, and implications regarding pathology in this population. METHODS: Forty-six amyloid-negative patients with late-life major depressive disorder (MDD) patients, including 23 SNAP (Aß-/ND+) and 23 Aß-/ND- MDD subjects, and 22 Aß-/ND-healthy control subjects were included in this study. Voxel-wise group comparisons between the SNAP MDD, Aß-/ND- MDD and control subjects were performed, adjusting for age, gender and level of education. For exploratory comparisons, 8 Aß+/ND- and 4 Aß+/ND + MDD patients were included in the Supplementary Material. RESULTS: The SNAP MDD patients had atrophy extending to regions outside the hippocampus, predominately in the medial temporal, dorsomedial and ventromedial prefrontal cortex; hypometabolism involving a large portion of the lateral and medial prefrontal cortex in addition to the bilateral temporal, parietal and precuneus cortex within typical Alzheimer disease regions were observed. Metabolism ratios of the inferior to the medial temporal lobe were significantly elevated in the SNAP MDD patients. We further discussed the implications with regards to underlying pathologies. CONCLUSION: The present study demonstrated characteristic patterns of atrophy and hypometabolism in patients with late-life major depression with SNAP. Identifying individuals with SNAP MDD may provide insights into currently unspecified neurodegenerative processes. Future refinement of neurodegeneration biomarkers is essential in order to identify potential pathological correlates while in vivo reliable pathological biomarkers are not forthcoming.

Pair Density Wave Order from Electron Repulsion.

A pair density wave (PDW) is a superconductor whose order parameter is a periodic function of space, without an accompanying spatially uniform component. Since PDWs are not the outcome of a weak-coupling instability of a Fermi liquid, a generic pairing mechanism for PDW order has remained elusive. We describe and solve models having robust PDW phases. To access the intermediate coupling limit, we invoke large-N limits of Fermi liquids with repulsive BCS interactions that admit saddle point solutions. We show that the requirements for long-range PDW order are that the repulsive BCS couplings must be nonmonotonic in space and that their strength must exceed a threshold value. We obtain a phase diagram with both finite temperature transitions to PDW order and a T=0 quantum critical point, where non-Fermi liquid behavior occurs.