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Schizophrenia is a complex mental disorder with high heritability and polygenic inheritance. Multimodal neuroimaging studies have also indicated that abnormalities of brain structure and function are a plausible neurobiological characterisation of schizophrenia. However, the polygenic effects of schizophrenia on these imaging endophenotypes have not yet been fully elucidated.
To investigate the effects of polygenic risk for schizophrenia on the brain grey matter volume and functional connectivity, which are disrupted in schizophrenia.
Genomic and neuroimaging data from a large sample of Han Chinese patients with schizophrenia (N = 509) and healthy controls (N = 502) were included in this study. We examined grey matter volume and functional connectivity via structural and functional magnetic resonance imaging, respectively. Using the data from a recent meta-analysis of a genome-wide association study that comprised a large number of Chinese people, we calculated a polygenic risk score (PGRS) for each participant.
The imaging genetic analysis revealed that the individual PGRS showed a significantly negative correlation with the hippocampal grey matter volume and hippocampus–medial prefrontal cortex functional connectivity, both of which were lower in the people with schizophrenia than in the controls. We also found that the observed neuroimaging measures showed weak but similar changes in unaffected first-degree relatives of patients with schizophrenia.
These findings suggested that genetically influenced brain grey matter volume and functional connectivity may provide important clues for understanding the pathological mechanisms of schizophrenia and for the early diagnosis of schizophrenia.
Health system reform is considered a tough issue worldwide. Great efforts have been made toward health system building and strengthening. However, it is still unclear which health system is appropriate for different countries. This study aimed to systematically compare the characteristics of the establishment periods between eighty-eight counties of National Health Service (NHS) and Social Health Insurance (SHI).
Forty-eight NHS countries and forty SHI countries with data availability were selected. The establishment years of current health systems and other eighteen indicators in economics, society, population and health during establishment periods were collected. Comparison between NHS and SHI was conducted by descriptive analysis of every indicator.
Most NHS countries were established during the cold war, while SHI had been set up since the cold war ended. The median of gross domestic product (GDP) per capita, urbanization rate and aging rate of SHI were USD 1535 in current dollars, 58.2 percent and 9.8 percent, respectively; compared with USD 1387, 41.2 percent and 4.7 percent, respectively of NHS. NHS countries had a smaller total population, lower mortality rate and elderly dependency ratio, while the birth rate and children's dependency ratio were higher. SHI countries showed a higher life expectancy and lower mortality rate in infants and children. NHS countries spent less in total health expenditure and a lower proportion of GDP. The median health expenditure per capita of SHI and NHS were USD 188 and USD 131 in current dollars, respectively. There was little difference among maternal mortality rates, and public and private health expenditure proportions.
NHS and SHI countries had different characteristics during the health system establishment periods. NHS was established earlier than SHI overall, so that SHI revealed higher levels in economic and social development. Health outcomes of NHS countries were slightly lower than SHI ones, while health expenditure was more in SHI countries. Specific social, economic, demographic and health conditions should be considered when countries are building their own health systems.
To identify the prevalence of posttraumatic stress disorder (PTSD) and its determinants among adolescents more than 4 years after the 2008 Wenchuan earthquake.
Adolescents (1,125 total) from 2 junior high schools in areas affected by the catastrophic earthquake were followed up for 3 years. The self-rating PTSD scale based on the Manual of Mental Disorders, 4th Edition (DSM-IV) and the Chinese Classification and Diagnostic Criteria of Mental Disorders, 2nd Edition, Revised (CCMD-2-R) was collected at 53 months, and determinant data were collected repeatedly. Logistic regression was used for a determinants analysis.
The prevalence of overall PTSD was 23.4% among the sample. The risk factors for PTSD were older age (OR=1.52, 95% CI: 1.20~1.92), and death or injury of a family member in the earthquake (OR=1.61, 95% CI: 1.09~2.37). Adolescents who had moderate-to-severe common mental health problems were more likely to have PTSD symptoms, with ORs from 3.98 to 17.67 (All P<0.05). Self-esteem remained a protective factor for PTSD regardless of age, whereas positive coping was a protective factor for PTSD when adolescents were older.
PTSD symptoms among adolescent survivors of a catastrophic earthquake seemed to persist over time. Long-term interventions are needed to alleviate PTSD symptoms among adolescent survivors. (Disaster Med Public Health Preparedness. 2019;13:414-418)
Northeastern China is a region of high tick abundance, multiple tick-borne pathogens and likely human infections. The spectrum of diseases caused by tick-borne pathogens has not been objectively evaluated in this region for clinical management and for comparison with other regions globally where tick-transmitted diseases are common. Based on clinical symptoms, PCR, indirect immunofluorescent assay and (or) blood smear, we identified and described tick-borne diseases from patients with recent tick bite seen at Mudanjiang Forestry Central Hospital. From May 2010 to September 2011, 42% (75/180) of patients were diagnosed with a specific tick-borne disease, including Lyme borreliosis, tick-borne encephalitis, human granulocytic anaplasmosis, human babesiosis and spotted fever group rickettsiosis. When we compared clinical and laboratory features to identify factors that might discriminate tick-transmitted infections from those lacking that evidence, we revealed that erythema migrans and neurological manifestations were statistically significantly differently presented between those with and without documented aetiologies (P < 0.001, P = 0.003). Twelve patients (6.7%, 12/180) were co-infected with two tick-borne pathogens. We demonstrated the poor ability of clinicians to identify the specific tick-borne disease. In addition, it is necessary to develop specific laboratory assays for optimal diagnosis of tick-borne diseases.
Porous silicon nitride ceramics are attracting extensive attention due to its high strength and low dielectric loss. However, further strength enhancement at elevated temperatures is hindered by its intergranular phase, forming from sintering additives. This paper describes the fabrication of porous silicon nitride ceramic materials, by using a replacement method of carbothermal nitridation. The initial samples which were obtained from the sintering of mixed powder consisted of 95 wt% Si3N4 and 5 wt% Y2O3. After the removal of the oxide intergranular phase and the infiltration of mixtures of phenolic resins and silica sols, carbothermal nitridation process was carried out at 1550 °C for 2 h under nitrogen. X-ray diffraction and microstructural analysis revealed a complete replacement of oxide intergranular phases by the newly formed Si3N4 intergranular phase. The unmodified ceramic exhibited lower flexural strength at 1400 °C, which was only 50% of the room-temperature strength. Although the modified ceramic attained a slightly lower flexural strength at room temperature after the replacement of intergranular phase, its strength measured at 1400 °C could attain 90% of room-temperature strength.
On April 25, 2015, a massive 8.1-magnitude earthquake struck Nepal at 2:11 pm (Beijing time). The 68-member-strong China International Search & Rescue Team (CISAR) left for Nepal at 6 am, April 26, to help with relief work. The CISAR was the first foreign team to rescue a survivor who was trapped beneath the rubble in the Gongabu area after the earthquake. On May 8, the team fulfilled the search-and-rescue mission and returned to Beijing. During the 2 weeks of rescue work, the team treated more than 3700 victims and cleared approximately 430 buildings. In this rescue mission, 10 experienced medical officers (including nine doctors and a nurse) from the General Hospital of Chinese People’s Armed Police Force (PAP) comprised the medical team of CISAR. In this report, we focus on the medical rescues by CISAR and discuss the characteristics of the medical rescue in Nepal. (Disaster Med Public Health Preparedness. 2018;12:536–538)
Mycoplasma infections are most frequently associated with disease in the urogenital or respiratory tracts and, in most cases, mycoplasmas infect the host persistently. In HIV-infected individuals the prevalence and role of genital mycoplasmas has not been well studied. To investigate the six species of Mycoplasma and the risk factors for infection in Jiangsu province, first-void urine and venous blood samples were collected and epidemiological questionnaires were administered after informed consent. A total of 1541 HIV/AIDS patients were recruited in this study. The overall infection rates of six Mycoplasma species were: Ureaplasma urealyticum (26·7%), Mycoplasma hominis (25·3%), M. fermentans (5·1%), M. genitalium (20·1%), M. penetrans (1·6%) and M. pirum (15·4%). The Mycoplasma infection rate in the unmarried group was lower than that of the married, divorced and widowed groups [adjusted odds ratio (aOR) 1·432, 95% confidence interval (CI) 1·077–1·904, P < 0·05]. The patients who refused highly active antiretroviral therapy (HAART) had a much higher risk of Mucoplasma infection (aOR 1·357, 95% CI 1·097–1·679, P < 0·05). Otherwise, a high CD4+ T cell count was a protective factor against Mycoplasma infection (aOR 0·576, 95% CI 0·460–0·719, P < 0·05). Further research will be required to confirm a causal relationship and to identify risk factors for Mycoplasma infection in HIV/AIDS populations.
This paper aims to obtain an analytical expression for the ratio of unloading work of indentation (Wu) to total loading work of indentation (Wt) (work recovery ratio of indentation) in instrumented spherical indentation. The expanding cavity model and Lamé solution are used. Three typical stress–strain relations (elastic-perfectly plastic, linear hardening, and power-law hardening) are analyzed. The results of finite-element method coincide with the expressions. The expressions show that the work recovery ratio of indentation is just related to plastic parameters. Furthermore, elastic work (We) are obtained, and it is proved that We should be distinguished from Wu in spherical indentation.
Reprogramming of DNA methylation in somatic cell nuclear transfer (SCNT) embryos is incomplete, and aberrant DNA methylation patterns are related to the inefficiency of SCNT. To facilitate nuclear reprogramming, this study investigated the effect of treating Guangxi Bama minipig donor cells with trichostatin A (TSA), 5-aza-2′-deoxycytine (5-aza-dC), or combination of TSA and 5-aza-dC prior to nuclear transfer. Analyses showed that there were no major changes in cell-cycle status among all groups. We monitored the transcription of DNMT1, DNMT3a, HDAC1 and IGF2 genes in donor cells. Transcription levels of HDAC1 were decreased significantly after treatment with a combination of TSA and 5-aza-dC, along with a significantly increased level of IGF2 (P < 0.05). Although treatment of donor cells with either TSA or 5-aza-dC alone resulted in non-significant effects in blastocyst formation rate and DNA methylation levels, a combination of TSA and 5-aza-dC significantly improved the development rates of minipig SCNT embryos to blastocyst (25.6% vs. 16.0%, P < 0.05). This change was accompanied by decreased levels of DNA methylation in somatic cells and blastocyst (P < 0.05). Thus in combination with TSA, lower concentrations of 5-aza-dC may produce a potent demethylating activity, and lead to the significantly enhanced blastocyst development percentage of Bama minipig SCNT embryos.
Fluorescent nanodiamonds (FNDs) with a size in the range of 10 – 100 nm have been produced by ion irradiation and annealing, and isolated by differential centrifugation. Single particle spectroscopic characterization with confocal fluorescence microscopy and fluorescence correlation spectroscopy indicates that they are photostable and useful as an alternative to far-red fluorescent proteins for bioimaging applications. We demonstrate the application by performing in vivo imaging of bare and bioconjugated FND particles (100 nm in diameter) in C. elegans and zebrafishes and exploring the interactions between this novel nanomaterial and the model organisms. Our results indicate that FNDs can be delivered to the embryos of both organisms by microinjection and eventually into the hatched larvae in the next generation. No deleterious effects have been observed for the carbon-based nanoparticles in vivo. The high fluorescence brightness, excellent photostability, and nontoxic nature of the nanomaterial have allowed long-term imaging and tracking of embryogenesis in the organisms.
This study describes the fabrication of hybrid micro- and nanostructures of semiconductor nanocrystals arranged in microscopic lines inside of a borosilicate glass doped with CdSxSe1-x. This was performed using a two step process of (1) ultrafast laser modification and (2) heat treatment. The glass was photomodified using focused sub-picosecond infra-red pulses with 1 MHz repetition rate to create linear domains with local compositional variations. Heat treating the sample at temperatures near glass transition preferentially precipitated semiconductor in the modified regions, as evidenced by confocal fluorescence microscopy. The optical properties of the precipitated nanocrystals varied with heat treatment duration.
The p-type conduction in transparent Ga-doped SnO2 thin films was realized and its two origins were discerned through comparison experiments associated with growth conditions, Rutherford backscattering spectroscopy and x-ray photoelectron spectroscopy analysis. All the experiment results suggest that the adsorbed oxygen both in the grain boundaries and at the surfaces is another origin of the net hole conduction in the polycrystalline thin films. This mechanism provides a fairy well explanation for the growth temperature dependence of the p-type conductivities of the films. It also offers a useful guide to better the properties of p-type conducting oxide thin films.
Involvement of Magnesium in Psychiatric Diseases
Dehua Chui, Neuroscience Research Institute & Department of Neurobiology, Key Laboratory for Neuroscience, Ministry of Education & Ministry of Public Health, Health Science Center, Peking University, Beijing 100191, China,
Zheng Chen, Department of Psychiatry & Institute for Geriatric Clinic and Rehabilitation, Beijing Geriatric Hospital, Beijing 100095, China,
Jia Yu, Department of Psychiatry & Institute for Geriatric Clinic and Rehabilitation, Beijing Geriatric Hospital, Beijing 100095, China,
Honglin Zhang, Department of Psychiatry & Institute for Geriatric Clinic and Rehabilitation, Beijing Geriatric Hospital, Beijing 100095, China,
Weishan Wang, Department of Psychiatry & Institute for Geriatric Clinic and Rehabilitation, Beijing Geriatric Hospital, Beijing 100095, China,
Yuetao Song, Department of Psychiatry & Institute for Geriatric Clinic and Rehabilitation, Beijing Geriatric Hospital, Beijing 100095, China,
Huan Yang, Neuroscience Research Institute & Department of Neurobiology, Key Laboratory for Neuroscience, Ministry of Education & Ministry of Public Health, Health Science Center, Peking University, Beijing 100191, China,
Yi Liu, Neuroscience Research Institute & Department of Neurobiology, Key Laboratory for Neuroscience, Ministry of Education & Ministry of Public Health, Health Science Center, Peking University, Beijing 100191, China
Alzheimer's disease (AD) is the most common form of dementia. It is characterized by a progressive cognitive impairment clinically, and excessive deposits of aggregated amyloid-β (Aβ) peptides pathologically. Environmental factors, including nutrition and metal elements, are implicated in the pathophysiology of AD. Magnesium (Mg) affects many biochemical mechanisms vital for neuronal properties and synaptic plasticity, including the response of N-methyl D-aspartate (NMDA) receptors to excitatory amino acids, stability and viscosity of the cell membrane and antagonism of calcium. Mg levels were found decreased in various tissues of AD patients and negatively correlated with clinical deterioration. Moreover, Mg was demonstrated to modulate the trafficking and processing of amyloid-β precursor protein (APP), which plays a central role in the pathogenesis of AD. Here, we review in vitro and in vivo data that indicated a role for magnesium in many biological and clinical aspects of AD.
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease in elderly people, affecting approximate 6∼8% of all individuals over the age of 65 years. AD is characterized by progressive cognitive impairment and distinct neuropathological lesions in the brain, including intracellular neurofibrillary tangles, extracellular parenchymal and cerebrovascular senile plaques (Braak and Braak, 1991).
Transparent p-type conducting Ga-doped SnO2 thin films were prepared using reactive rf-magnetron sputtering. Good p-type conduction was directly realized without the need of postdeposition annealing. The p-type conductivity was found to be very sensitive to the growth condition and process, suggesting that the carrier behavior is strongly related to the fine microstructure of the films. The microstructures of the films were characterized using synchrotron X-ray diffraction and specular reflectivity techniques. The valence state of the Ga dopant was measured from X-ray photoelectron spectra to explain the origin of net holes presented in the films.
Angiostrongylus cantonensis infection causes eosinophilic meningitis in humans. Baicalein is a flavonoid originally isolated from the roots of Scutellaria baicalensis Georgi. In this study we evaluated the efficacy of the combination of albendazole and baicalein for treating eosinophilic meningitis in BALB/c mice. Therapeutic efficacy included the survival time, body weight, neurological function, leucocyte and eosinophil counts, eotaxin concentration, matrix metalloproteinase-9 (MMP-9) activity, larval recovery and histopathological examination. The results showed that the combination of albendazole and baicalein was more effective than either drug administered singly. Combination therapy increased the survival time, decreased body weight loss, neurological dysfunction, leucocyte response, eotaxin concentration and MMP-9 activity. Our results suggest that the combination of albendazole and baicalein may exhibit synergistic beneficial effects in the treatment of eosinophilic meningitis induced by A. cantonensis.
Miniature pigs are valuable for research in xenotransplantation and as models for investigating human diseases. Although many mammalian species have been cloned, the success rates have been very low, especially in the pig. In the present study, an attempt was made to optimize somatic cell nuclear transfer (SCNT) protocols for use in the production of the Guangxi Bama mini-pig. Firstly, mini-pig fibroblast cells from a new-born Guangxi Bama piglet were isolated and cultured. Cell type was identified by fluorescence immunocytochemistry (ICC); the cells expressed cimentin, but not cytoceratin and follicular stimulation hormone receptor (FSHR). Secondly, the optimal cell cycle synchronization protocol for treating fibroblast cells from the newborn piglet's testicle was investigated by contact inhibition and serum starvation. When fibroblast cells were treated by contact inhibition, a higher fusion (66.0% vs. 58.3%, p > 0.05) and blastocyst production (20.8% vs. 15.1, p > 0.05) rates were obtained than with serum starvation. Thirdly, to examine the ability of old cells to be morphologically remodelled after activation, testicular fibroblasts (passage 10–14) were introduced into enucleated oocytes; enlarged nuclei were formed in most of the reconstructed embryos at 6 h and enlarged nuclei or distinct pseudopronuclei were formed in nearly all the reconstructed embryos at 12 h. The old donor cell could be morphologically remodelled correctly and was competent to support embryo development to the blastocyst in vitro. Fourthly, the in vitro development potential of the cloned embryos was investigated using two types of donor cell: ear fibroblasts and low or high passage testicular fibroblasts. The rate of fusion was highest using low passage testicle fibroblasts (84.5% vs. 69.8% and 80.0%, p < 0.05), as was development to the blastocyst stage (14.6% vs. 7.7% and 6.3%, p < 0.05). Finally, the effect of phytohaemagglutinin (PHA) on parthenogenetic and cloned embryo development was examined. The PHA had no significant effect on the parthenogenetic embryos, but cloned embryo development to the blastocyst stage was significantly increased by PHA (10μg/ml), (13.4% vs. 5.6% and 5.6%, p < 0.05).
Background: Increasing evidence suggests that neprilysin (NEP) may be the major degrading enzyme of amyloid beta (Aβ) in the brain and the NEP gene has been proposed as a candidate gene for Alzheimer's disease (AD). Association results between the NEP gene and AD are still preliminary. This study investigates the effect of the polymorphisms of −204G/C and 159C/T in the NEP gene on the development of sporadic Alzheimer's disease (SAD) in a southern Chinese community.
Method: 236 sporadic late-onset AD patients were recruited from Guangzhou Psychiatric Hospital in southern China, and 332 healthy elderly controls were enrolled from three old age homes in suburban Guangzhou. NEP and ApoE genotype were determined by PCR–RFLP.
Results: No differences in genotypic and allelic frequencies of −204G/C and 159C/T polymorphisms in NEP were found between AD and control group (for −204G/C genotype: χ2 = 2.34, P > 0.05; for allele: χ2 = 2.31, P > 0.05; for 159C/T genotype: χ2 = 1.34, P > 0.05; for allele: χ2 = 0.88, P > 0.05). Neither was any difference found in genotypic and allelic frequency when stratified by sex or by ApoE ε4 allele (P > 0.05).
Conclusions: Our results suggest that −204G/C and 159C/T polymorphisms of the NEP gene may not be associated with SAD. Moreover, both sex and ApoE ε4 allele do not affect the distribution of NEP gene polymorphisms.
Ronnie Vernooy, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Li Xiaoyun, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Xu Xiuli, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Lu Min, Senior Programme Specialist, International Development Research Centre (IDRC), Canada,Qi Gubo, Senior Programme Specialist, International Development Research Centre (IDRC), Canada