Unexpected FDG Uptake in the Cerebral Parenchyma in Subacute Subarachnoid Hemorrhage.

ABSTRACT: Changes in cerebral glucose metabolism after subarachnoid hemorrhage have been rarely described. We present a case with subacute subarachnoid hemorrhage showing unexpected elevated FDG uptake at adjacent cerebral parenchyma on FDG PET/CT. The density of the cerebral parenchyma was normal on CT. The patient received medical management without any neurological complication.

Live or heat-killed probiotic administration reduces anxiety and central cytokine expression in BALB/c mice, but differentially alters brain neurotransmitter gene expression.

While the potential for probiotic supplements to act as adjunctive treatments for mood disorders has been widely demonstrated, the precise mode of action remains unclear. To investigate the psychotropic effects of a multi-species probiotic on emotional behaviour in male BALB/c mice, we explored the potential mechanisms of action relating to the temporal changes in the mRNA expression of brain cytokines, BDNF, central 5HT receptor and serotonin transporter (SERT) and GABA receptor in the context of probiotic induced behavioural changes. The effects of a heat-killed probiotic, independent of microbial metabolic processes were also evaluated on the same outcomes to understand whether the host response to the bacteria is more or less important than the contribution of the metabolic activity of the bacteria themselves. Results showed that probiotic supplementation reduced anxiety-like behaviours, increased time spent in the light area of the light-dark box, and decreased the expression of pro-inflammatory cytokines in the brain. Furthermore, probiotic administration elevated hippocampal BDNF and decreased GABAB1ß expression. Interestingly, the heat-killed probiotic and its membrane fraction had similar effects on emotional behaviours and gene expression in the brain. The ingestion of live and heat-killed probiotic preparations also reduced TLR2 expression in the gut. Thus, the present study reveals that the anxiolytic action of a multispecies probiotic in BALB/c mice is independent of bacterial viability. This suggests that it is the host response to probiotics, rather than microbial metabolism that facilitates the molecular changes in the brain and downstream behaviours. This article is part of the Special Issue on "Microbiome & the Brain: Mechanisms & Maladies".

Actigraphic sleep monitoring in patients with post-traumatic stress disorder (PTSD): A meta-analysis.

OBJECTIVE: Sleep disruption is a common complaint among patients with post-traumatic stress disorder (PTSD). Modern technology of activity monitoring (actigraphy) enables extended, objective, unobtrusive recording and measuring of daytime and nighttime activity. We conducted a meta-analysis to investigate the actigraphic sleep patterns in PTSD compared with healthy controls. METHODS: We searched through seven electronic databases from inception to July 2022. Only case-control studies comparing rest-activity variables measured by actigraphy devices between clinically diagnosed PTSD patients and healthy individuals were included. RESULTS: We identified 12 eligible studies comparing 323 PTSD patients and 416 healthy controls. Using a random-effects model, we showed that PTSD patients have significantly lower sleep efficiency (SMD: -0.26, 95 % CI = -0.51 to -0.004, p < .05, I2 = 29.31 %), more fragmented sleep (SMD: 0.52, 95 % CI = 0.17 to 0.87, p < .01, I2 = 0 %), and longer time in bed (SMD: 0.41, 95 % CI = 0.07 to 0.74, p < .05, I2 = 0 %) compared to healthy controls. LIMITATIONS: This study included a limited number of studies. Publication bias was not examined on all variables, which could lead to an overestimation of effect size. Four studies involved veterans, which likely differ from civilians regarding traumatic exposure. CONCLUSION: This meta-analytic review highlighted a pattern of sleep disturbances in PTSD patients compared with non-PTSD individuals. High-quality, large-scale studies are necessary to draw a definitive conclusion regarding the distinctive sleep profile in PTSD. Future research can pay attention to sleep-specific mechanisms underlying PTSD and explore the momentary interactions between sleep-wake variables.

Uses of Antibiotics in Ornamental Fish in Hong Kong and the Antibiotic Resistance in the Associated Zoonotic Pathogens.

The use of antibiotics in ornamental fish is not regulated, as they are not intended for human consumption. Although antibiotic resistant bacteria have been detected in ornamental fish worldwide, there have been no studies to look at the situation in Hong Kong. Therefore, the present study was conducted to investigate the use of antibiotics in ornamental fish. Ornamental fish were purchased from five local pet fish shops and the antibiotics in carriage water were quantified using liquid chromatography tandem mass spectrometry. Moreover, Aeromonas and Pseudomonas spp. present in carriage water were isolated and their minimum inhibitory concentrations against selected antibiotics were determined. Results indicated that among the twenty antibiotics screened, doxycycline (0.0155-0.0836 µg L-1), oxytetracycline (0.0102-29.0 µg L-1), tetracycline (0.0350-0.244 µg L-1), enrofloxacin (0.00107-0.247 µg L-1), and oxalinic acid (n.d.-0.514 µg L-1) were detected in all sampled shops. Additionally, MIC results revealed that some of the Aeromonas and Pseudomonas spp. isolates were highly resistant to all antibiotics selected. Our findings confirmed that multiple antibiotics are being used in ornamental fish and the associated bacteria are resistant to selected antibiotics, suggesting that this could be a significant transmission route of antibiotic resistant bacteria to household indoor environments.

Isothermal Background-Free Nucleic Acid Quantification by a One-Pot Cas13a Assay Using Droplet Microfluidics.

High sensitivity and specificity nucleic acid detection has been achieved by the Cas13a collateral effect in combination with a separate recombinase polymerase amplification (RPA). However, these emerging methods cannot provide accurate quantification of nucleic acids because the two-step assay performance may be compromised if the RPA and Cas13a reactions are simply unified in a single step. In this work, we first addressed the challenges associated with enzymatic incompatibility and the macromolecular crowding effect in the one-pot assay development, making the consolidated RPA-Cas13a assay a facile and robust diagnostic tool. Next, we found that the one-pot reaction cannot precisely quantify the targets at low concentrations. Thus, by leveraging droplet microfluidics, we converted the one-pot assay to a digital quantification format, termed Microfluidics-Enabled Digital Isothermal Cas13a Assay (MEDICA). Due to the droplet compartmentation, MEDICA greatly accelerates the reaction and enables relative detection in 10 min and the end-point quantification in 25 min. Moreover, MEDICA facilitates the droplet binarization for counting because of background-free signals generated by trans-cleavage reporting of Cas13a. Our clinical validation highlights that CRISPR-based isothermal assays are promising for the next generation of nucleic acid quantification methods.

Droplet digital recombinase polymerase amplification (ddRPA) reaction unlocking via picoinjection.

Recombinase polymerase amplification (RPA) has been recognized as a promising isothermal amplification method for nucleic acid detection. However, the digital format of RPA is still challenging to implement due to its MgOAc-initiated reaction feature and the inherent non-specific amplification. Here we develop a Picoinjection Aided Digital reaction unLOCKing (PADLOCK) approach utilizing droplet microfluidics to achieve droplet digital RPA (ddRPA) for absolute nucleic acid quantification. By coupling a microfluidic picoinjector with a droplet generator, the reaction initiator MgOAc is dosed into droplets containing MgOAc-deprived RPA master mix for controlled digital reaction unlocking, which completely circumvents premature amplification. The discretization of the targets to a single-molecule level in confined droplets endows absolute quantification of the copy number. Coupled with CRISPR/Cas13a sensing, the ddRPA demonstrates single molecule detection ability within 30 min with significantly enhanced signal-to-noise ratio (S/N ratio>6) and uniform fluorescence signal reporting, facilitating the precise quantification of nucleic acids. Furthermore, the utility of the PADLOCK-CRISPR assay has been validated with 22 clinical samples, which generated results in 100% concordance with qPCR. We believe the coupling of droplet microfluidic technology with digital RPA will pave the way towards ultrasensitive and precise nucleic acid quantification.

Mom's diet matters: Maternal prebiotic intake in mice reduces anxiety and alters brain gene expression and the fecal microbiome in offspring.

Compelling evidence links enteric microbes to brain function and behavior. Galacto-oligosaccharide prebiotics have been shown to modulate the composition of gut flora and induce metabolic, neurochemical, and behavioral changes in adult rodents. Despite the brain being most susceptible to environmental factors, such as nutrients and toxins, during the earliest stages of development, it is unknown whether maternal prebiotic supplementation during gestation and lactation influences the offspring gut microbiome, brain, or behavior. The aim of this study was to test whether maternal galacto-oligosaccharide intake during pregnancy and lactation alters the brain and behavior in naïve and endotoxin-challenged offspring. CD1 female mice received either normal drinking water or water supplemented with Bimuno® galacto-oligosaccharides (B-GOS) during gestation and suckling. Offspring behavior was tested at weaning age or adulthood, and a cross-foster design was employed in a separate cohort to differentiate between effects of prenatal and postnatal maternal B-GOS intake. Lipopolysaccharide was also administered to pups at postnatal day 9 to determine whether maternal B-GOS influences the neurobiological and behavioral effects of a neonatal pro-inflammatory challenge in adulthood. Fecal microbiome composition and metabolites were analyzed to explore potential relationships between the maternal microbiome, the offspring gut microbiome, and the offspring brain and behavior. Maternal B-GOS supplementation increased exploratory behavior and reduced expression of hippocampal glutamate receptor genes in young, weaning-age offspring. In addition, postnatal, but not prenatal, B-GOS supplementation increased fecal butyrate and propionate levels. Finally, in adult offspring, perinatal B-GOS intake increased cortical glutamate receptor subunits in females, increased social preference, and reduced anxiety. We provide novel and comprehensive evidence for the influence of maternal prebiotic intake on offspring behavior, brain gene expression, and gut microbiome composition in mice.

Prebiotic reduction of brain histone deacetylase (HDAC) activity and olanzapine-mediated weight gain in rats, are acetate independent.

The intestinal microbiome is emerging as a novel therapeutic target owing to the wide range of potential health benefits that could result by manipulating the microbiota composition through relatively simple interventions. Ingestion of the prebiotic Bimuno™ galacto-oligosaccharide (B-GOS®) is one such intervention that has been shown to attenuate olanzapine-induced weight gain and improve cognitive flexibility in rats, potentially through mechanisms involving acetate, the major short-chain fatty acid (SCFA) that is produced by B-GOS® fermentation. The present study investigated the individual influences of B-GOS® and sodium acetate intake on brain histone acetyltransferase (HAT) and histone deacetylase (HDAC) activities, cortical and hippocampal expression of HDAC1-4 and N-methyl-d-aspartate receptor subunits in saline or olanzapine injected female rats. The effect of sodium acetate on olanzapine-induced weight gain was also investigated. Daily ingestion of B-GOS® for 21 days, reduced HDAC activity and hippocampal HDAC-4, and elevated levels of cortical HDAC-1 and HDAC-3 mRNAs. Sodium acetate supplementation significantly decreased HAT, but not HDAC, activity and increased hippocampal HDAC-3 and HDAC-4 mRNAs. Olanzapine-induced weight gain and fourteen genera of intestinal bacteria, were not influenced by sodium acetate intake. Together these data suggests the effects of B-GOS® in rats cannot be replicated by acetate ingestion, and that mechanisms beyond the production of this SCFA are likely to underlie the psychotropic and metabolic actions of this prebiotic.

Changing experiences of work dirtiness, occupational disidentification, and employee withdrawal.

Research and theory concerning "dirty work" has largely focused on how employees cope with stable features of their jobs. From a study of employees' experiences across 6 weekly repeated measurements, we found that within-person increases in experienced dirtiness were positively related to their withdrawal behaviors and job change propensity indirectly through occupational disidentification. Assessed at the between-subjects level, team-oriented leadership moderated the indirect within-person effects of work dirtiness experiences on these outcomes. The relationships between elevations in experienced work dirtiness and occupational disidentification were more strongly positive at lower levels of team-oriented leadership. Analyses also showed that individuals' perceptions of occupational stigma independently moderated the within-person relationship between experienced dirtiness and occupational disidentification. We discuss theoretical implications for the literature on dirty work and practical implications for mitigating the adverse outcomes associated with experienced work dirtiness. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Chinese translation and validation of the Walking Impairment Questionnaire in patients with peripheral artery disease.

The Walking Impairment Questionnaire (WIQ) is a frequently used questionnaire to evaluate patients with intermittent claudication on four subscales: pain severity, walking distance, walking speed and the ability to climb stairs. The aim of this study is to translate and validate the WIQ in Chinese. After translation and cultural adaptation of the WIQ, 134 patients with intermittent claudication completed the Chinese WIQ and European Quality of Life 5 Dimension (EQ-5D). Walking distances were determined by the 6-minute walk test (6MWT). Correlations between the WIQ, quality of life questionnaire and walking distances were calculated to determine validity. Reliability and internal consistency were determined using the intra-class correlation coefficient (ICC) and Cronbach's alpha (α), respectively. Significant correlations were found between the WIQ score, initial claudication distance (ICD), absolute claudication distance (ACD) and all domains of the EQ-5D (all p ≤ 0.01). Test-retest reliability (ICC = 0.74) and the overall internal consistency determined (α = 0.90) showed good agreement. A lower WIQ score corresponded to shorter walking distances. In conclusion, this study showed that the Chinese version of the WIQ is a valid, reliable and clinically relevant instrument for assessing walking impairment in patients with intermittent claudication.

Objective assessment of walking environments in ultra-dense cities: development and reliability of the Environment in Asia Scan Tool--Hong Kong version (EAST-HK).

The 91-item Environment in Asia Scan Tool--Hong Kong (EAST-HK) was developed to objectively assess aspects of the neighbourhood environment hypothesised to affect walking in Hong Kong and similar ultra-dense Asian metropolises. Reliability was assessed by four pairs of raters auditing 422 street segments, 204 on two occasions. Seventy-one items showed sufficient variability and reliability. These can be used to estimate neighbourhood walkability in Hong Kong. Fourteen items showed good reliability but limited variability and may be used in a more variable context. Auditing of only 50% of street segments may be sufficient to obtain representative estimates of neighbourhood walkability.

Solvation effects on the intracluster elimination channels in M+(L)n, where M+= Mg+ and Ca+, L = CH3OH, and NH3, and n = 2-6.

The methanol and ammonia solvated Ca (+) or Mg (+) clusters are known to go through intracluster H or CH 3 eliminations which are typically switched on just below n = 6. By first principles calculations at the B3LYP/6-311+G** level, we have identified the transition structures, activation barriers, and energy changes in these reactions for clusters with 2-6 solvent molecules. The activation barrier is crucial to explain the previously reported experimental results. While increasing number of solvent molecules stabilizes a transition structure, the increasing presence of solvent molecules in the first solvation shell makes it difficult for the metal ion to assist the bond breaking through its interaction with the departing H atom or CH 3 group. The balance of these two factors determines whether a particular elimination channel could be switched on.

Theoretical study on the intracluster elimination channels for Mg+(CH3OH), Ca+(CH3OH), Mg+(NH3), and Ca+(NH3).

The intracluster elimination reactions in solvated alkaline earth metal monocation clusters, M (+)L n , are known to be size-dependent, indicating links between chemical reactivity and the solvation environment controlled by the cluster size. For the methanol and ammonia clusters, there are a number of competing elimination channels involving the breaking of O-H, C-H, O-CH 3, or N-H bond. In this report, we focus on the four clusters with only one solvent molecule and systematically map out the reaction paths and intermediates. The interaction between the metal ion and the departing H atom or CH 3 group varies considerably, depending on the interaction between the metal ion and the remaining group. The understanding of the nature of these interactions and the evaluation of various theoretical levels in treating these reactions provide a solid base for the investigation of the solvation effects on the chemical reactivity of the larger clusters.

Functional expression of eukaryotic membrane proteins in Lactococcus lactis.

The overproduction of eukaryotic membrane proteins is a major impediment in their structural and functional characterization. Here we have used the nisin-inducible expression system of Lactococcus lactis for the overproduction of 11 mitochondrial transport proteins from yeast. They were expressed at high levels in a functional state in the cytoplasmic membrane. The results also show that the level of expression is influenced by the N-terminal regions of the transporters. Expression levels were improved >10-fold either by replacing or truncating these regions or by adding lactococcal signal peptides. The observed expression levels are now compatible with a realistic exploration of crystallization conditions. The lactococcal expression system may be used for the high-throughput functional characterization of eukaryotic membrane proteins and structural genomics.

Eukaryotic membrane protein overproduction in Lactococcus lactis.

Eukaryotic membrane proteins play many vital roles in the cell and are important drug targets. Approximately 25% of all genes identified in the genome are known to encode membrane proteins, but the vast majority have no assigned function. Although the generation of structures of soluble proteins has entered the high-throughput stage, for eukaryotic membrane proteins only a dozen high-resolution structures have been obtained so far. One major bottleneck for the functional and structural characterisation of membrane proteins is the overproduction of biologically active material. Recent advances in the development of the Lactococcus lactis expression system have opened the way for the high-throughput functional expression of eukaryotic membrane proteins.

A novel ADP/ATP transporter in the mitosome of the microaerophilic human parasite Entamoeba histolytica.

Recent data suggest that microaerophilic and parasitic protozoa, which lack oxidative phosphorylation, nevertheless contain mitochondrial homologs [1-6], organelles that share common ancestry with mitochondria. Such widespread retention suggests there may be a common function for mitochondrial homologs that makes them essential for eukaryotic cells. We determined the mitochondrial carrier family (MCF) complement of the Entamoeba histolytica mitochondrial homolog, also known as a crypton [5] or more commonly as a mitosome [3]. MCF proteins support mitochondrial metabolic energy generation, DNA replication, and amino-acid metabolism by linking biochemical pathways in the mitochondrial matrix with those in the cytosol [7]. MCF diversity thus closely mirrors important facets of mitochondrial metabolic diversity. The Entamoeba histolytica mitosome has lost all but a single type of MCF protein, which transports ATP and ADP via a novel mechanism that is not reliant on a membrane potential. Phylogenetic analyses confirm that the Entamoeba ADP/ATP carrier is distinct from archetypal mitochondrial ADP/ATP carriers, an observation that is supported by its different substrate and inhibitor specificity. Because many functions of yeast and human mitochondria rely on solutes transported by specialized members of this family, the Entamoeba mitosome must contain only a small subset of these processes requiring adenine nucleotide exchange.

The elimination of a hydrogen atom in Na(H2O)n.

By a systematic examination on Na(H2O)n, with n = 4-7, 9, 10, and 15, we demonstrate that a hydrogen loss reaction can be initiated by a single sodium atom with water molecules. This reaction is similar to the well-known size-dependent intracluster hydrogen loss in Mg+(H2O)n, which is isoelectronic to Na(H2O)n. However, with one less charge on Na(H2O)n than that on Mg+(H2O)n, the hydrogen loss for Na(H2O)n is characterized by a higher barrier and a more flexible solvation shell around the metal ion, although the reaction should be accessible, as the lowest barrier is around 8 kcal/mol. Interestingly, the hydroxide ion OH- produced in the process is stabilized by the solvation of H2O molecules and the formation of an ion pair Na+(H2O)4(H2O)n-l-4[OH-(H2O)l]. The activation barrier is reduced as the unpaired electron in Na(H2O)n moves to higher solvation shells with increasing cluster size, and the reaction is not switched off for larger clusters. This is in sharp contrast to the reaction for Mg+(H2O)n, in which the OH- ion is stabilized by direct coordination with Mg2+ and the reaction is switched off for n > 17, as the unpaired electron moved to higher solvation shells. Such a contrast illustrates the important link between microsolvation environment and chemical reactivity in solvation clusters.