The Microbiome-Gut-Brain Axis in Health and Disease.

One of the most important scientific discoveries of recent years was the disclosure that the intestinal microflora takes part in bidirectional communication between the gut and the brain. Scientists suggest that human gut microflora may even act as the “second brain” and be responsible for neurodegenerative disorders like Alzheimer’s disease (AD). Although human-associated microbial communities are generally stable, they can be altered by common human actions and experiences. Enteric bacteria, commensal, and pathogenic microorganisms, may have a major impact on immune system, brain development, and behavior, as they are able to produce several neurotransmitters and neuromodulators like serotonin, kynurenine, catecholamine, etc., as well as amyloids. However, brain destructive mechanisms, that can lead to dementia and AD, start with the intestinal microbiome dysbiosis, development of local and systemic inflammation, and dysregulation of the gut-brain axis. Increased permeability of the gut epithelial barrier results in invasion of different bacteria, viruses, and their neuroactive products that support neuroinflammatory reactions in the brain. It seems that, inflammatory-infectious hypothesis of AD, with the great role of the gut microbiome, starts to gently push into the shadow the amyloid cascade hypothesis that has dominated for decades. It is strongly postulated that AD may begin in the gut, and is closely related to the imbalance of gut microbiota. This is promising area for therapeutic intervention. Modulation of gut microbiota through personalized diet or beneficial microbiota intervention, alter microbial partners and their products including amyloid protein, will probably become a new treatment for AD.

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The Gut Microbiome Alterations and Inflammation-Driven Pathogenesis of Alzheimer’s Disease—a Critical Review

MoS2 becomes an efficient and durable nonprecious-metal electrocatalyst for the hydrogen evolution reaction (HER) when it contains multifunctional active sites for water splitting derived from 1T-phase, defects, S vacancies, exposed Mo edges with expanded interlayer spacings. In contrast to previously reported MoS2 -based catalysts targeting only a single or few of these characteristics, the all-in-one MoS2 catalyst prepared herein features all of the above active site types. During synthesis, the intercalation of in situ generated NH3 molecules into MoS2 sheets affords ammoniated MoS2 (A-MoS2 ) that predominantly comprises 1T-MoS2 and exhibits an expanded interlayer spacing. The subsequent reduction of A-MoS2 results in the removal of intercalated NH3 and H2 S to form an all-in-one MoS2 with multifunctional active sites mentioned above (R-MoS2 ) that exhibits electrocatalytic HER performance in alkaline media superior to those of all previously reported MoS2 -based electrocatalysts. In particular, a hybrid MoS2 /nickel foam catalyst outperforms commercial Pt/C in the practically meaningful high-current region (>25 mA cm-2 ), demonstrating that R-MoS2 -based materials can potentially replace Pt catalysts in practical alkaline HER systems.

Efficient Hydrogen Evolution Reaction Catalysis in Alkaline Media by All‐in‐One MoS2 with Multifunctional Active Sites

The development of abundant and cheap electrocatalysts for the hydrogen evolution reaction (HER) has attracted increasing attention over recent years. However, to achieve low-cost HER electrocatalysis, especially in alkaline media, is still a big challenge due to the sluggish water dissociation kinetics as well as the poor long-term stability of catalysts. In this paper we report the design and synthesis of a two-dimensional (2D) MoS2 confined Co(OH)2 nanoparticle electrocatalyst, which accelerates water dissociation and exhibits good durability in alkaline solutions, leading to significant improvement in HER performance. A two-step method was used to synthesize the electrocatalyst, starting with the lithium intercalation of exfoliated MoS2 nanosheets followed by Co2+ exchange in alkaline media to form MoS2 intercalated with Co(OH)2 nanoparticles (denoted Co-Ex-MoS2), which was fully characterized by spectroscopic studies. Electrochemical tests indicated that the electrocatalyst exhibits superior HER acti...

Two-Dimensional MoS2 Confined Co(OH)2 Electrocatalysts for Hydrogen Evolution in Alkaline Electrolytes

Gut microbiota is characterized by an inter-individual variability due to genetic and environmental factors. Among the environmental ones, dietary habits play a key role in the modulation of gut microbiota composition. There are main differences between the intestinal microbiota of subjects fed with prevalent Western diet and that of subjects with a diet rich in fibers. Specific changes in the composition of gut microbiota have been demonstrated among subjects according to a different dietary intake. A particular diet may promote the growth of specific bacterial strains, driving hosts to a consequent alteration of fermentative metabolism, with a direct effect on intestinal pH, which can be responsible for the development of a pathogenic flora. Moreover, a high-fat diet can promote the development of a pro-inflammatory gut microbiota, with a consequent increase of intestinal permeability and, consequently, of circulating levels of lipopolysaccharides. In this review, we discuss the direct role of the diet in the composition of gut microbiota and about the possible clinical consequences.

The role of diet on gut microbiota composition

The Microbiota-Gut-Brain Axis and Its Potential Therapeutic Role in Autism Spectrum Disorder

Ammonia intercalated flower-like MoS2 electrocatalyst film assembled by vertical orientated ultrathin nanosheet on graphite sheethas been successfully synthesized using one-step hydrothermal method. In this strategy, ammonia can effectively insert into the parallel plane of the MoS2 nanosheets, leading to the expansion of lattice and phase transfer from 2H to 1T, generating more active unsaturated sulfur atoms. The flower-like ammoniated MoS2 electrocatalysts with more active sites and large surface area exhibited excellent HER activity with a small Tafel slope and low onset overpotential, resulting a great enhancement in hydrogen evolution. The high efficient activity and recyclable utilization, as well as large-scale, indicate that it is a very promising electrocatalyst to replace Pt in industry application.

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Ammonia intercalated flower-like MoS2 nanosheet film as electrocatalyst for high efficient and stable hydrogen evolution.

Coronavirus disease 2019 (COVID-19) pandemic may exert adverse impacts on sleep among populations, which may raise awareness of the burden of sleep disturbance, and the demand of intervention strategies for different populations. We aimed to summarize the current evidence for the impacts of COVID-19 on sleep in patients with COVID-19, healthcare workers (HWs), and the general population. We searched PubMed and Embase for studies on the prevalence of sleep disturbance. Totally, 86 studies were included in the review, including 16 studies for COVID-19 patients, 34 studies for HWs, and 36 studies for the general population. The prevalence of sleep disturbance was 33.3%-84.7%, and 29.5-40% in hospitalized COVID-19 patients and discharged COVID-19 survivors, respectively. Physiologic and psychological traumatic effects of the infection may interact with environmental factors to increase the risk of sleep disturbance in COVID-19 patients. The prevalence of sleep disturbance was 18.4-84.7% in HWs, and the contributors mainly included high workloads and shift work, occupation-related factors, and psychological factors. The prevalence of sleep disturbance was 17.65-81% in the general population. Physiologic and social-psychological factors contributed to sleep disturbance of the general population during COVID-19 pandemic. In summary, the sleep disturbance was highly prevalent during COVID-19 pandemic. Specific health strategies should be implemented to tackle sleep disturbance.

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Burden of Sleep Disturbance During COVID-19 Pandemic: A Systematic Review

The cumulative effect of air pollutants on the acute exacerbation of COPD in Shanghai, China.

STUDY OBJECTIVES To compare a positive airway pressure (PAP) device's detection of respiratory events and airway status during device-detected apneas with events scored on simultaneous polysomnography (PSG) DESIGN Prospective PSGs of patients with sleep apnea using a new-generation PAP device SETTINGS Four clinical and academic sleep centers PATIENTS Forty-five patients with obstructive sleep apnea (OSA) and complex sleep apnea (Comp SA) performed a PSG on PAP levels adjusted to induce respiratory events INTERVENTIONS None MEASUREMENTS AND RESULTS PAP device data identifying the type of respiratory event and whether the airway during a device-detected apnea was open or obstructed were compared to time-synced, manually scored respiratory events on simultaneous PSG recording Intraclass correlation coefficients between device-detected and PSG scored events were 0854 for apnea-hypopnea index (AHI), 0783 for apnea index, 0252 for hypopnea index, and 0098 for respiratory event-related arousals index At a device AHI (AHIFlow) of 10 events/h, area under the receiver operating characteristic curve was 098, with sensitivity 092 and specificity 084 AHIFlow tended to overestimate AHI on PSG at values less than 10 events/h The device detected that the airway was obstructed in 874% of manually scored obstructive apneas Of the device-detected apneas with clear airway, a minority (158%) were manually scored as obstructive apneas CONCLUSIONS A device-detected apnea-hypopnea index (AHIFlow) < 10 events/h on a positive airway pressure device is strong evidence of good treatment efficacy Device-detected airway status agrees closely with the presumed airway status during polysomnography scored events, but should not be equated with a specific type of respiratory event

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Qing Yun Li

Papers

The Microbiota-Gut-Brain Axis and Its Potential Therapeutic Role in Autism Spectrum Disorder

Ammonia intercalated flower-like MoS2 nanosheet film as electrocatalyst for high efficient and stable hydrogen evolution.

Burden of Sleep Disturbance During COVID-19 Pandemic: A Systematic Review

The cumulative effect of air pollutants on the acute exacerbation of COPD in Shanghai, China.

Detection of upper airway status and respiratory events by a current generation positive airway pressure device.