Imaging the Meissner effect in hydride superconductors using quantum sensors.

By directly altering microscopic interactions, pressure provides a powerful tuning knob for the exploration of condensed phases and geophysical phenomena1. The megabar regime represents an interesting frontier, in which recent discoveries include high-temperature superconductors, as well as structural and valence phase transitions2-6. However, at such high pressures, many conventional measurement techniques fail. Here we demonstrate the ability to perform local magnetometry inside a diamond anvil cell with sub-micron spatial resolution at megabar pressures. Our approach uses a shallow layer of nitrogen-vacancy colour centres implanted directly within the anvil7-9; crucially, we choose a crystal cut compatible with the intrinsic symmetries of the nitrogen-vacancy centre to enable functionality at megabar pressures. We apply our technique to characterize a recently discovered hydride superconductor, CeH9 (ref. 10). By performing simultaneous magnetometry and electrical transport measurements, we observe the dual signatures of superconductivity: diamagnetism characteristic of the Meissner effect and a sharp drop of the resistance to near zero. By locally mapping both the diamagnetic response and flux trapping, we directly image the geometry of superconducting regions, showing marked inhomogeneities at the micron scale. Our work brings quantum sensing to the megabar frontier and enables the closed-loop optimization of superhydride materials synthesis.

Emergent hydrodynamics in a strongly interacting dipolar spin ensemble.

Conventional wisdom holds that macroscopic classical phenomena naturally emerge from microscopic quantum laws1-7. However, despite this mantra, building direct connections between these two descriptions has remained an enduring scientific challenge. In particular, it is difficult to quantitatively predict the emergent 'classical' properties of a system (for example, diffusivity, viscosity and compressibility) from a generic microscopic quantum Hamiltonian7-14. Here we introduce a hybrid solid-state spin platform, where the underlying disordered, dipolar quantum Hamiltonian gives rise to the emergence of unconventional spin diffusion at nanometre length scales. In particular, the combination of positional disorder and on-site random fields leads to diffusive dynamics that are Fickian yet non-Gaussian15-20. Finally, by tuning the underlying parameters within the spin Hamiltonian via a combination of static and driven fields, we demonstrate direct control over the emergent spin diffusion coefficient. Our work enables the investigation of hydrodynamics in many-body quantum spin systems.

Verified quantum information scrambling.

Quantum scrambling is the dispersal of local information into many-body quantum entanglements and correlations distributed throughout an entire system. This concept accompanies the dynamics of thermalization in closed quantum systems, and has recently emerged as a powerful tool for characterizing chaos in black holes1-4. However, the direct experimental measurement of quantum scrambling is difficult, owing to the exponential complexity of ergodic many-body entangled states. One way to characterize quantum scrambling is to measure an out-of-time-ordered correlation function (OTOC); however, because scrambling leads to their decay, OTOCs do not generally discriminate between quantum scrambling and ordinary decoherence. Here we implement a quantum circuit that provides a positive test for the scrambling features of a given unitary process5,6. This approach conditionally teleports a quantum state through the circuit, providing an unambiguous test for whether scrambling has occurred, while simultaneously measuring an OTOC. We engineer quantum scrambling processes through a tunable three-qubit unitary operation as part of a seven-qubit circuit on an ion trap quantum computer. Measured teleportation fidelities are typically about 80 per cent, and enable us to experimentally bound the scrambling-induced decay of the corresponding OTOC measurement.

Observation of a discrete time crystal.

Spontaneous symmetry breaking is a fundamental concept in many areas of physics, including cosmology, particle physics and condensed matter. An example is the breaking of spatial translational symmetry, which underlies the formation of crystals and the phase transition from liquid to solid. Using the analogy of crystals in space, the breaking of translational symmetry in time and the emergence of a 'time crystal' was recently proposed, but was later shown to be forbidden in thermal equilibrium. However, non-equilibrium Floquet systems, which are subject to a periodic drive, can exhibit persistent time correlations at an emergent subharmonic frequency. This new phase of matter has been dubbed a 'discrete time crystal'. Here we present the experimental observation of a discrete time crystal, in an interacting spin chain of trapped atomic ions. We apply a periodic Hamiltonian to the system under many-body localization conditions, and observe a subharmonic temporal response that is robust to external perturbations. The observation of such a time crystal opens the door to the study of systems with long-range spatio-temporal correlations and novel phases of matter that emerge under intrinsically non-equilibrium conditions.

Effects of adverse childhood experiences on the Charlson comorbidity index in US adults.

OBJECTIVES: The aim of this article was to explore the association between adverse childhood experiences (ACEs) and the Charlson comorbidity index (CCI) and to provide valuable information for public health professionals and policymakers to improve quality of life and reduce mortality. STUDY DESIGN: A cross-sectional analysis was conducted using data pooled from the 2020 Behavioral Risk Factor Surveillance System (BRFSS). METHODS: This study involved 102,393 US adult participants from the 2020 BRFSS. The zero-inflated negative binomial (ZINB) and mixed graphical model (MGM) models were used to explore the effect of ACEs on CCI and the interaction between ACEs. RESULTS: In the count part of the model (CCI ≥0), sexual abuse had the strongest association with CCI (relative risk [RR] = 1.111, P < 0.001). In the logit part of the model (CCI = 0), the likelihood of having CCI equal to 0 decreased by 23.0% for household substance abuse, which was the highest percentage decrease for all ACEs. Compared to those with ACE scores equal to 0, individuals with ACE scores ≥4 have an expected CCI RR of 1.222, and the likelihood of having CCI equal to 0 decreased by 50.2%. Household substance abuse and incarceration history in the home had the strongest association among interactions of ACEs (0.85). CONCLUSIONS: Associations between ACEs and CCI were observed in this study, and these associations differed between genders. The findings of this study provide data to design strategies for disease prevention and improvement of quality of life.

[Construction of a nomogram model for predicting 2-year survival rate of small cell lung cancer based on more comprehensive variables].

Objective: To construct a novel prognostic nomogram model based on more comprehensive variables for patients with small-cell lung cancer (SCLC). Methods: The data of 722 patients with SCLC confirmed by pathology in Affiliated Cancer Hospital of Shanxi Medical University from January 2015 to December 2018 were retrospectively analyzed [including 592 males and 130 females, aged from 23 to 82(61±9) years]. A random seed count of 133 was used to divide those patients into training set (n=422) and validation set (n=300). Kaplan-Meier was used for survival curves analysis and univariate Log-rank test was used for evaluating the influence of clinical variables on the prognosis of sclc, variables with P<0.05 in univariate analysis were included in a multivariate Cox regression model. The nomogram was constructed based on the variables which P<0.05 in multivariate analysis. Receiver operating characteristic (ROC) curve, calibration by Integrated Brier score (IBS) and clinical net benefit by decision curve analysis (DCA) were used to evaluate model discriminative power, prediction error value, and clinical net benefit, and compared with the American Joint Committee on Cancer 8th TNM. Results: Male, abnormal monocyte (MON) counts, abnormal neuron specific enolase (NSE), abnormal cytokeratin 19 fragment (Cyfra211), M1a stage, M1b stage, M1c stage, radiotherapy (RT), chemotherapy ≥4 cycles and prophylactic cranial irradiation (PCI) were prognostic factors for SCLC[HR(95%CI)=1.39(1.00-1.92), 1.29(1.02-1.63), 1.41(1.11-1.80), 2.02(1.48-2.76), 1.09(0.77-1.55), 1.44(0.94-2.22), 2.01(1.49-2.71), 0.75(0.57-0.98), 0.40(0.31-0.51)and 0.42(0.26-0.68), respectively, all P<0.05]. The area under ROC curve (AUC) of the nomogram in training set and validation set were 0.814(95%CI: 0.765-0.862)and 0.787 (95%CI: 0.725-0.849), which were higher than TNM [0.616(95%CI: 0.558-0.674) and 0.648(95%CI: 0.581-0.715)].The calibration curve showed a good correlation between the nomogram prediction and actual observation for the 2-year overall survival (OS). IBS indicted a lower prediction error rate (training set: 0.132 vs 0.169; validation set: 0.138 vs 0.169). DCA showed a wider threshold range than TNM (training set: 0.01-0.96 vs 0.01-0.85, validation set: 0.01-0.94 vs 0.01-0.86) and a greater improvement of the clinical net benefit (in training set the nomogram had a greater clinical benefit than TNM in the range of 0.19-0.96, and remained in validation set in the range of 0.19-0.94). Conclusion: The established nomogram model for predicting 2-year OS in patients with SCLC based on 8 variables, including gender, MON, NSE, Cyfra211, M stage, RT, CT cycles and PCI can be used for an more accurately prognosis prediction and reference for therapeutic regimen selection.

[The effect of maternal HBV DNA levels on HBV intrauterine transmission and fetal distress].

Aim: To identify the key risk factors of intrauterine hepatitis B virus transmission (HBV) and its effect on the placenta and fetus. Methods: 425 infants born to hepatitis B surface antigen (HBsAg)-positive pregnant women who received combined immunization with hepatitis B immunoglobulin and hepatitis B vaccine between 2009 to 2015 were prospectively enrolled in this study. The intrauterine transmission situation was assessed by dynamic monitoring of infants HBV DNA load and quantitative HBsAg. Univariate and multivariate regression analysis was used to determine the high risk factors for intrauterine transmission. Stratified analysis was used to determine the relationship between maternal HBV DNA load and fetal distress. Transmission electron microscopy was used to observe HBV Effects on placental tissue. Results: HBV intrauterine infection rate was 2.6% (11/425). Multivariate analysis result showed that the maternal HBV DNA load was an independent risk factor for intrauterine infection among infants (P=0.011). Intrauterine infection and distress rate was significantly higher in infants with with maternal HBV DNA>106 IU/ml than those with HBV DNA <106 IU/ml (12.2% vs. 1.8%; χ2=11.275, P=0.006), and (24.4% vs. 16.0%, χ2=3.993, P=0.046). Transmission electron microscopy showed that mitochondrial edema, endoplasmic reticulum expansion and thicker basement membrane were apparent when the maternal HBV DNA>106 IU/ml than that of maternal HBV DNA<106 IU/ml (960 nm vs. 214 nm, Z=-2.782, P=0.005) in the placental tissue. Conclusion: Maternal HBV DNA>106 IU/ml is associated not only with intrauterine infection, but also with increased incidence of intrauterine distress and placental sub-microstructural changes, providing strong clinical and histological evidence for pregnancy avoidance and treatment in this population.

[Comparison study for the proportion of underdiagnosed zonulopathy in angle closure glaucoma].

Objective: To analyze the proportion and clinical characteristics of underdiagnosed zonulopathy in angle closure glaucoma (ACG) patients and to explore the related risk factors. Methods: Case-control study. Continuous cases of ACG patients who underwent phacoemulsification combined with intraocular lens implantation and goniosynechialysis surgery [ACG group, including acute angle closure glaucoma (AACG) and chronic angle closure glaucoma (CACG)] from November 1, 2020 to October 31, 2021 and age-related cataract patients who underwent phacoemulsification combined with intraocular lens implantation surgery in the same period (control group) were included. The diagnosis of zonulopathy was determined according to the intraoperative signs such as wrinkles of the anterior capsule during continuous circular capsulorhexis. The proportion of zonulopathy, preoperative diagnosis rate of zonulopathy, demographic characteristics, anterior chamber depth (ACD), axis length, difference of ACD in both eyes (ACD of the contralateral eye minus ACD of the operated eye) were compared between the two groups. The related risk factors were explored. The paired t-test (comparison between two groups of normally distributed data), non-parametric test (comparison between two groups of non-normally distributed data), Chi-square test (categorical variables), univariate and multivariate logistic regression analysis were used. Results: There were 104 ACG patients (104 eyes), including 63 AACG patients (63 eyes) and 41 CACG patients (41 eyes), and 117 controls (117 eyes). There was no significant difference in age (P=0.29) and gender (P=0.07) between the two groups. The ACG group had shallower anterior chamber (P<0.001), shorter axial length (P<0.001) and more ACD difference in both eyes (P<0.001). In the ACG group, the proportion of zonulopathy was 46.2% (48/104), which was significantly higher than that (6.0%, 7/117) in the control group (P<0.001). In the control group, only zonular laxity was found, while in the ACG group, besides the predominant zonular laxity (68.8%, 33/48), there was zonular dehiscence (31.3%, 15/48). The eyes with AACG (57.1%, 36/63) had a higher proportion of zonulopathy than those with CACG (29.3%, 12/41) (P=0.006). In the ACG group, only 14 cases (29.8%) were diagnosed preoperatively according to slit lamp examination and/or ultrasound biomicroscopy. The proportion of underdiagnosed zonulopathy was 70.8% in the ACG group (34/48). A smaller ACD was found to be related to the zonulopathy in the ACG group. All AACG cases with an ACD ≤2.0 mm and CACG cases with an ACD ≤1.9 mm had zonulopathy. Multivariate logistic regression showed that the ACD difference in both eyes (P=0.025) and the diagnosis of ACG (AACG vs. cataract, P<0.001; CACG vs. cataract, P=0.023) were independent risk factors associated with zonulopathy. Conclusions: The proportion of underdiagnosed zonulopathy among ACG patients is high. Better preoperative diagnostic methods for zonulopathy are needed. Zonulopathy is common in ACG patients, especially in AACG patients, suggesting that zonulopathy may be related to the pathogenesis of ACG. The shallower the ACD, the riskier the zonulopathy. ACD differences between two eyes and ACG types (including AACG and CACG) were related risk factors of zonulopathy.(This article was published ahead of print on the Online-First Publishing Platform for Excellent Scientific Researches of Chinese Medical Association Publishing House on March 11, 2022).

[Expression of PTTG1 in gastric adenocarcinoma tissues and its relationship with prognosis].

Objective: To identify new prognostic markers and therapeutic targets for gastric adenocarcinoma. Methods: The public datasets of gastric adenocarcinoma collected from GEO database (GSE33335 and GSE63089) were downloaded for analysis. There were 70 GC tissues and paired normal tissues in the two profile datasets. Differentially expressed genes (DEGs) between GC tissues and normal stomach tissues were selected by the R software. Protein-protein interaction (PPI) of these DEGs were visualized by the Search Tool for the Retrieval of Interacting Genes (STRING). The key gene sets were analyzed by Cytoscape and Molecular Complex Detection (MCODE). The mRNA and protein expression levels of prognosis related genes identified by public database were confirmed by using GC tissues and paired normal tissues collected from July 2019 to September 2019 in Affiliated Hospital of Nantong University. Results: DEGs were identified in the two datasets by using R software. A total of 128 DEGs were detected, including 85 up-regulated genes (log(2)FC>1.2 and FDR<0.01) and 43 down-regulated genes (log(2)FC<-1.2 and FDR<0.01) in the GC tissues. PPI network model and MCODE model were established by using the Online String tool and Cytoscape software, and 27 key genes were obtained, including 25 genes related with prognosis of GC patients (P<0.05). We identified 14 significant DEGs in GC tissues, including cyclin B1 (CCNB1), polo-like kinase 1 (PLK1) and pituitary-tumor transforming gene (PTTG1), which were significantly enriched in the cell cycle pathway through KEGG pathway enrichment analysis. The positive expression rate of PTTG1 in GC tissues was 68.8% (22/32), significantly higher than 18.8% (6/32) in normal gastric tissues (P<0.05). Conclusions: The expression of PTTG1 is different in GC and gastric tissues, implicates it is the key gene in gastric carcinogenesis. The prognoses of GC patients with higher PTTG1 expression are worse. PTTG1 might participate in the development of gastric adenocarcinoma by regulating cell cycle.

The histone deacetylase inhibitor chidamide induces intermittent viraemia in HIV-infected patients on suppressive antiretroviral therapy.

OBJECTIVES: To evaluate the safety and efficacy of chidamide to reverse HIV-1 latency in vivo and to compare the effects of four clinically tested histone deacetylase (HDAC) inhibitors on non-histone proteins in vitro. METHODS: Participants received chidamide orally at 10 mg twice weekly for 4 weeks while maintaining baseline antiretroviral therapy. The primary outcome was plasma viral rebound during chidamide dosing and the secondary outcomes were safety, pharmacokinetic and pharmacodynamic profiles, changes in cell-associated HIV-1 RNA and HIV-1 DNA, and immune parameters. Western blotting was used to compare the in vitro effects of the four HDAC inhibitors on HSP90, NF-κB and AP-1. RESULTS: Seven aviraemic participants completed eight oral doses of chidamide, and only grade 1 adverse events were observed. Cyclic increases in histone acetylation were also detected. All participants showed robust and repeated plasma viral rebound (peak viraemia 147-3850 copies/mL), as well as increased cell-associated HIV-1 RNA, during chidamide treatment. Furthermore, we identified an enhanced HIV-1-specific cellular immune response and a modest 37.7% (95% CI: 12.7-62.8%, P = 0.028) reduction in cell-associated HIV-1 DNA. Compared with the other three HDAC inhibitors, chidamide had minimal cytotoxicity in vitro at clinically relevant concentrations and showed mechanistically superior effects on non-histone proteins, including HSP90, NF-κB and AP-1. CONCLUSIONS: Chidamide safely and vigorously disrupts HIV-1 latency in vivo, which makes it a promising latency-reversing agent.

Preventive Beneficial Effect of an Aqueous Extract of Phyllanthus amarus Schum. and Thonn. (Euphorbiaceae) on DOCA-Salt-Induced Hypertension, Cardiac Hypertrophy and Dysfunction, and Endothelial Dysfunction in Rats.

This study investigated the preventive effect of an aqueous extract of the whole plant of Phyllanthus amarus (AEPA) on blood pressure, cardiac, and endothelial function in the deoxycorticosterone acetate (DOCA) salt-induced hypertensive rat model. Male Wistar rats were assigned into 5 groups receiving either vehicle (control and DOCA salt), DOCA salt combined with AEPA at 100 or 300 mg/kg, or AEPA (100 mg/kg) alone for 5 weeks. In addition, DOCA salt-treated rats were allowed free access to water containing 1% NaCl. Systolic blood pressure, left ventricle parameters, vascular reactivity of primary mesenteric artery rings, the vascular level of oxidative stress, and the level of target proteins were determined, using respectively tail-cuff sphygmomanometry, echocardiography, organ chambers, dihydroethidium staining, and immunofluorescence methods. After 5 weeks, AEPA treatments (100 or 300 mg/kg per day) significantly prevented the increase in systolic blood pressure in DOCA salt-treated rats, respectively, by about 24 and 21 mm Hg, improved cardiac diastolic function, and reduced significantly the increased posterior and septum diastolic wall thickness and the left ventricle mass in hypertensive rats. Moreover, the DOCA salt-induced endothelial dysfunction and the blunted nitric oxide- and endothelium-dependent hyperpolarization-mediated relaxations in primary mesenteric artery were improved after the AEPA treatments. AEPA also reduced the level of vascular oxidative stress and the expression level of target proteins (eNOS, COX-2, NADPH oxidase subunit p22) in DOCA salt rats. Altogether, AEPA prevented hypertension, improved cardiac structure and function, and improved endothelial function in DOCA salt rats. Such beneficial effects seem to be related, at least in part, to normalization of the vascular level of oxidative stress.

Spatial and temporal distribution of infectious disease epidemics, disasters and other potential public health emergencies in the World Health Organisation Africa region, 2016-2018.

BACKGROUND: Emerging and re-emerging diseases with pandemic potential continue to challenge fragile health systems in Africa, creating enormous human and economic toll. To provide evidence for the investment case for public health emergency preparedness, we analysed the spatial and temporal distribution of epidemics, disasters and other potential public health emergencies in the WHO African region between 2016 and 2018. METHODS: We abstracted data from several sources, including: the WHO African Region's weekly bulletins on epidemics and emergencies, the WHO-Disease Outbreak News (DON) and the Emergency Events Database (EM-DAT) of the Centre for Research on the Epidemiology of Disasters (CRED). Other sources were: the Program for Monitoring Emerging Diseases (ProMED) and the Global Infectious Disease and Epidemiology Network (GIDEON). We included information on the time and location of the event, the number of cases and deaths and counter-checked the different data sources. DATA ANALYSIS: We used bubble plots for temporal analysis and generated graphs and maps showing the frequency and distribution of each event. Based on the frequency of events, we categorised countries into three: Tier 1, 10 or more events, Tier 2, 5-9 events, and Tier 3, less than 5 or no event. Finally, we compared the event frequencies to a summary International Health Regulations (IHR) index generated from the IHR technical area scores of the 2018 annual reports. RESULTS: Over 260 events were identified between 2016 and 2018. Forty-one countries (87%) had at least one epidemic between 2016 and 2018, and 21 of them (45%) had at least one epidemic annually. Twenty-two countries (47%) had disasters/humanitarian crises. Seven countries (the epicentres) experienced over 10 events and all of them had limited or developing IHR capacities. The top five causes of epidemics were: Cholera, Measles, Viral Haemorrhagic Diseases, Malaria and Meningitis. CONCLUSIONS: The frequent and widespread occurrence of epidemics and disasters in Africa is a clarion call for investing in preparedness. While strengthening preparedness should be guided by global frameworks, it is the responsibility of each government to finance country specific needs. We call upon all African countries to establish governance and predictable financing mechanisms for IHR implementation and to build resilient health systems everywhere.

Identification of potential crucial genes associated with vasculogenic mimicry in human osteosarcoma based on gene expression profile.

We previously reported the presence of vasculogenic mimicry (VM) in human osteosarcoma. However, the mechanistic basis of osteosarcoma VM remains unclear. Three hundred eighty-one upregulated differentially expressed genes (DEGs) and 526 downregulated DEGs between human osteosarcoma cell line 143B and HOS cell exposed to Matrigel were screened out by microarray. GO categories such as "cell adhesion", "angiogenesis" were enriched in 143B group. PATHWAY analysis showed enriched TGF-beta, Wnt and VEGF signaling pathway in 143B group. The hub gene ITGA2 in signal-network of DEGs exhibited pro-VM and pro-metastasis effect. Our study provides fundamental data for further studies regarding molecules involved in osteosarcoma VM.

[Clinical characteristics and influencing factors of patients with novel coronavirus pneumonia combined with liver injury in Shaanxi region].

Objective: To understand the clinical characteristics, change of liver function, influencing factors and prognosis in hospitalized patients with coronavirus disease-19 (COVID-19) combined with liver injury. Methods: The general conditions, biochemical indicators of liver, blood clotting mechanism, routine blood test, UGT1A1 * 28 gene polymorphism and other data of 40 cases with COVID-19 admitted to the isolation ward of Tangdu Hospital were retrospectively analyzed. The clinical characteristics, influencing factors and prognosis of liver injury in patients with liver injury group and those with normal liver function group were compared. The mean of two samples in univariate analysis was compared by t-test and analysis of variance. The counting data was measured by χ(2) tests. The non-normal distribution measurement data were described by the median, and the non-parametric test was used. Statistically significant influencing factors were used as the independent variables in univariate analysis. Multiple logistic regression analysis was used to analyze the main influencing factors of liver injury. Results: Of the 40 cases, 25 were male (62.5%) and 15 were female (37.5%), aged 22 to 83 (53.87 ± 15.84) years. Liver injury was occurred in 22 cases (55%) during the course of the disease. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level was initially increased (4.4 to 3.5 times of the normal value) along with decrease of albumin in the second week, and the difference was statistically significant (P < 0.001). Ten cases (43.5%) had highest abnormal total blood bilirubin (54.1 µmol/ L). There was no correlation between the increase in transaminase and the increase in total blood bilirubin (R = -0.006, P = 0.972). Three cases had prothrombin activity (PTA) of ≤50%, 10 cases had elevated FDP, and 13 cases had elevated D-dimer, all of whom were severe or critically ill. Liver function injury was more likely to occur in patients who used many types of drugs and large amounts of hormones (P = 0.002, P = 0.031), and there was no correlation with the TA6TA7 mutation in the UGT1A1 * 28 gene locus. Multiple regression analysis showed that the occurrence of liver injury was only related to critical illness. The liver function of all patients had recovered within one week after conventional liver protection treatment. Conclusion: COVID-19 combined with liver function injury may be due to the slight elevation of transaminase, mostly around the second week of the disease course. Severe patients have a higher proportion of liver injury, and critical type is an independent risk factor for liver injury.

Ketamine and its metabolite (2R,6R)-hydroxynorketamine induce lasting alterations in glutamatergic synaptic plasticity in the mesolimbic circuit.

Low doses of ketamine trigger rapid and lasting antidepressant effects after one injection in treatment-resistant patients with major depressive disorder. Modulation of AMPA receptors (AMPARs) in the hippocampus and prefrontal cortex is suggested to mediate the antidepressant action of ketamine and of one of its metabolites (2R,6R)-hydroxynorketamine ((2R,6R)-HNK). We have examined whether ketamine and (2R,6R)-HNK affect glutamatergic transmission and plasticity in the mesolimbic system, brain regions known to have key roles in reward-motivated behaviors, mood and hedonic drive. We found that one day after the injection of a low dose of ketamine, long-term potentiation (LTP) in the nucleus accumbens (NAc) was impaired. Loss of LTP was maintained for 7 days and was not associated with an altered basal synaptic transmission mediated by AMPARs and N-methyl-D-aspartate receptors (NMDARs). Inhibition of mammalian target of rapamycin signaling with rapamycin did not prevent the ketamine-induced loss of LTP but inhibited LTP in saline-treated mice. However, ketamine blunted the increase in the phosphorylation of the GluA1 subunit of AMPARs at a calcium/calmodulin-dependent protein kinase II/protein kinase C site induced by an LTP induction protocol. Moreover, ketamine caused a persistent increased phosphorylation of GluA1 at a protein kinase A site. (2R,6R)-HNK also impaired LTP in the NAc. In dopaminergic neurons of the ventral tegmental area from ketamine- or (2R,6R)-HNK-treated mice, AMPAR-mediated responses were depressed, while those mediated by NMDARs were unaltered, which resulted in a reduced AMPA/NMDA ratio, a measure of long-term synaptic depression. These results demonstrate that a single injection of ketamine or (2R,6R)-HNK induces enduring alterations in the function of AMPARs and synaptic plasticity in brain regions involved in reward-related behaviors.

Cortical abnormalities in bipolar disorder: an MRI analysis of 6503 individuals from the ENIGMA Bipolar Disorder Working Group.

Despite decades of research, the pathophysiology of bipolar disorder (BD) is still not well understood. Structural brain differences have been associated with BD, but results from neuroimaging studies have been inconsistent. To address this, we performed the largest study to date of cortical gray matter thickness and surface area measures from brain magnetic resonance imaging scans of 6503 individuals including 1837 unrelated adults with BD and 2582 unrelated healthy controls for group differences while also examining the effects of commonly prescribed medications, age of illness onset, history of psychosis, mood state, age and sex differences on cortical regions. In BD, cortical gray matter was thinner in frontal, temporal and parietal regions of both brain hemispheres. BD had the strongest effects on left pars opercularis (Cohen's d=-0.293; P=1.71 × 10-21), left fusiform gyrus (d=-0.288; P=8.25 × 10-21) and left rostral middle frontal cortex (d=-0.276; P=2.99 × 10-19). Longer duration of illness (after accounting for age at the time of scanning) was associated with reduced cortical thickness in frontal, medial parietal and occipital regions. We found that several commonly prescribed medications, including lithium, antiepileptic and antipsychotic treatment showed significant associations with cortical thickness and surface area, even after accounting for patients who received multiple medications. We found evidence of reduced cortical surface area associated with a history of psychosis but no associations with mood state at the time of scanning. Our analysis revealed previously undetected associations and provides an extensive analysis of potential confounding variables in neuroimaging studies of BD.

Nanometre-scale thermometry in a living cell.

Sensitive probing of temperature variations on nanometre scales is an outstanding challenge in many areas of modern science and technology. In particular, a thermometer capable of subdegree temperature resolution over a large range of temperatures as well as integration within a living system could provide a powerful new tool in many areas of biological, physical and chemical research. Possibilities range from the temperature-induced control of gene expression and tumour metabolism to the cell-selective treatment of disease and the study of heat dissipation in integrated circuits. By combining local light-induced heat sources with sensitive nanoscale thermometry, it may also be possible to engineer biological processes at the subcellular level. Here we demonstrate a new approach to nanoscale thermometry that uses coherent manipulation of the electronic spin associated with nitrogen-vacancy colour centres in diamond. Our technique makes it possible to detect temperature variations as small as 1.8 mK (a sensitivity of 9 mK Hz(-1/2)) in an ultrapure bulk diamond sample. Using nitrogen-vacancy centres in diamond nanocrystals (nanodiamonds), we directly measure the local thermal environment on length scales as short as 200 nanometres. Finally, by introducing both nanodiamonds and gold nanoparticles into a single human embryonic fibroblast, we demonstrate temperature-gradient control and mapping at the subcellular level, enabling unique potential applications in life sciences.

Imaging the Local Charge Environment of Nitrogen-Vacancy Centers in Diamond.

Characterizing the local internal environment surrounding solid-state spin defects is crucial to harnessing them as nanoscale sensors of external fields. This is especially germane to the case of defect ensembles which can exhibit a complex interplay between interactions, internal fields, and lattice strain. Working with the nitrogen-vacancy (NV) center in diamond, we demonstrate that local electric fields dominate the magnetic resonance behavior of NV ensembles at a low magnetic field. We introduce a simple microscopic model that quantitatively captures the observed spectra for samples with NV concentrations spanning more than two orders of magnitude. Motivated by this understanding, we propose and implement a novel method for the nanoscale localization of individual charges within the diamond lattice; our approach relies upon the fact that the charge induces a NV dark state which depends on the electric field orientation.

Critical Thermalization of a Disordered Dipolar Spin System in Diamond.

Statistical mechanics underlies our understanding of macroscopic quantum systems. It is based on the assumption that out-of-equilibrium systems rapidly approach their equilibrium states, forgetting any information about their microscopic initial conditions. This fundamental paradigm is challenged by disordered systems, in which a slowdown or even absence of thermalization is expected. We report the observation of critical thermalization in a three dimensional ensemble of ∼10^{6} electronic spins coupled via dipolar interactions. By controlling the spin states of nitrogen vacancy color centers in diamond, we observe slow, subexponential relaxation dynamics and identify a regime of power-law decay with disorder-dependent exponents; this behavior is modified at late times owing to many-body interactions. These observations are quantitatively explained by a resonance counting theory that incorporates the effects of both disorder and interactions.

Seroepidemiology of diphtheria and pertussis in Chongqing, China: serology-based evidence of Bordetella pertussis infection.

OBJECTIVES: In order to gain further insight into the seroepidemiology of Bordetella pertussis infection and immunity against diphtheria in Chongqing, China, the concentrations of antibodies to pertussis toxin (PT) and diphtheria toxin (DT) were investigated in a healthy population. STUDY DESIGN: Cross-sectional study. METHODS: In total, 1080 healthy people were recruited into this study. Sera antibodies to DT and PT were measured quantitatively using commercial enzyme-linked immunosorbent assay kits. Age-specific incidence of infection with B. pertussis was estimated and compared with notified cases of pertussis. RESULTS: The mean concentration of anti-DT IgG was 0.71 IU/ml (95% confidence interval [CI] = 0.60-0.82), with a positive rate (>0.01 IU/ml) of 97.41% (1052/1080). The mean concentration of anti-PT IgG was 7.65 IU/ml (95% CI = 6.65-8.65), with a positive rate (>100 IU/ml) of 1.17% (11/944). The estimated pertussis infection rate was 7290/100,000, which was far higher than the reported incidence of 1.29/100,000 in 2015. The peaks of estimated incidence of infection were found in subjects aged 7-14 years (9971/100,000) and ≥20 years (13,898/100,000). CONCLUSIONS: B. pertussis infection occurs frequently in young infants and adolescents/adults; the latter are often responsible for the transmission of pertussis to young infants. The existing surveillance system may underestimate the true incidence of pertussis in older age groups in Chongqing, and the immunisation programme should be improved to provide protection against pertussis for adolescents and young adults.