International Variations in Dementia and Alzheimer Disease Diagnosis and Certification Habits and Their Associations With Dementia and Alzheimer Disease Mortality: A Cross-Sectional Study of 38 Countries.

OBJECTIVE: To examine international variations in national diagnosis and certification habits prefer recording dementia (D) versus Alzhiemer disease (AD) as the underlying cause of death (UCOD) and their associations with mortality rates of dementia and AD. METHODS: We calculated proportions of D/D+AD and AD/D+AD deaths as proxies of national diagnosis and certification habits. Pearson correlation coefficients (r) were estimated to assess the associations of proportions with the mortality rates of dementia or AD among adults aged 75 to 84 years across 38 countries. RESULTS: The countries with a high preference for recording dementia as the UCOD were Taiwan and Latvia with proportion of D/D+AD deaths of 92% and 88%, respectively, and those with a high preference for recording AD as the UCOD were Slovenia, Turkey, and Poland with proportion of AD/D+AD deaths of 100%, 99%, and 89%, respectively. The r values for the proportions and mortality rate for dementia and AD were 0.67 (95% CI: 0.44-0.81) and 0.46 (95% CI: 0.16-0.68), respectively. CONCLUSION: We identified a small number of countries with obvious natonal diagnosis and certification habits preferring dementia or AD and had moderate effects on international variations in the mortality rates of dementia and AD.

A new method for characterizing piezoelectric properties of hexagonal boron nitride nanoflakes activated by focused ultrasound.

Piezoelectric nanomaterials wirelessly activated by ultrasound have been studied for biomedical applications. However, the quantitative measurement of piezoelectric effects in nanomaterials and the correlation between the ultrasound dose and the piezoelectric amplitude are still explored. We demonstrated the synthesis of boron nitride nanoflakes by mechanochemical exfoliation and employed the electrochemical method to quantitatively evaluate the piezoelectric performance of the nanoflakes under ultrasonic circumstances. The change of voltametric charge, current, and voltage in response to different acoustic pressure was obtained in the electrochemical system. The charge was reached up to 69.29 µC with a net increase of 49.54 µC/mm2 under 2.976 MPa. The output current was measured up to 597 pA/mm2 and positive shift of output voltage shifted from -600 mV to -450 mV. Additionally, the piezoelectric performance linearly increased with acoustic pressure. The proposed method could be a standardized evaluation test bench for characterization of ultrasound-mediated piezoelectric nanomaterials.

Vascular oxidative stress causes neutrophil arrest in brain capillaries, leading to decreased cerebral blood flow and contributing to memory impairment in a mouse model of Alzheimer’s disease.

INTRODUCTION: In this study, we explore the role of oxidative stress produced by NOX2-containing NADPH oxidase as a molecular mechanism causing capillary stalling and cerebral blood flow deficits in the APP/PS1 mouse model of AD. METHODS: We inhibited NOX2 in APP/PS1 mice by administering a 10 mg/kg dose of the peptide inhibitor gp91-ds-tat i.p., for two weeks. We used in vivo two-photon imaging to measure capillary stalling, penetrating arteriole flow, and vascular inflammation. We also characterized short-term memory function and gene expression changes in cerebral microvessels. RESULTS: We found that after NOX2 inhibition capillary stalling, as well as parenchymal and vascular inflammation, were significantly reduced. In addition, we found a significant increase in penetrating arteriole flow, followed by an improvement in short-term memory, and downregulation of inflammatory gene expression pathways. DISCUSSION: Oxidative stress is a major mechanism leading to microvascular dysfunction in AD, and represents an important therapeutic target.

Large-Volume Focused-Ultrasound Mild Hyperthermia for Improving Blood-Brain Tumor Barrier Permeability Application.

Mild hyperthermia can locally enhance permeability of the blood-tumor barrier in brain tumors, improving delivery of antitumor nanodrugs. However, a clinical transcranial focused ultrasound (FUS) system does not provide this modality yet. The study aimed at the development of the transcranial FUS technique dedicated for large-volume mild hyperthermia in the brain. Acoustic pressure, multiple-foci, temperature and thermal dose induced by FUS were simulated in the brain through the skull. A 1-MHz, 114-element, spherical helmet transducer was fabricated to verify large-volume hyperthermia in the phantom. The simulated results showed that two foci were simultaneously formed at (2, 0, 0) and (-2, 0, 0) and at (0, 2, 0) and (0, -2, 0), using the phases of focusing pattern 1 and the phases of focusing pattern 2, respectively. Switching two focusing patterns at 5 Hz produced a hyperthermic zone with an ellipsoid of 7 mm × 6 mm × 11 mm in the brain and the temperature was 41-45 °C in the ellipsoid as the maximum intensity was 150 W/cm2 and sonication time was 3 min. The phased array driven by switching two mode phases generated a 41 °C-contour region of 10 ± 1 mm × 8 ± 2 mm × 13 ± 2 mm in the phantom after 3-min sonication. Therefore, we have demonstrated our developed FUS technique for large-volume mild hyperthermia.

Metabolic and Obesity Phenotype Trajectories in Taiwanese Medical Personnel.

The distribution of metabolic and obesity phenotypes in Taiwanese medical personnel is unknown. In this study, trajectory analysis with repeated measurements was used to explore the development and associated risk factors of different metabolic and obesity phenotypes in hospital staff from a Taiwanese medical center. The results demonstrated that metabolically unhealthy workers presented with a higher body mass index (BMI) compared with their metabolically healthy counterparts. Male and aged > 40 years hospital workers were more likely to be in a deleterious metabolic/obesity state. Meanwhile, profession and working hours were not significantly associated with the development of certain phenotypes in our study. These results shed light on the necessity of adequate data retrieval regarding working hours, and a nuanced examination of working conditions among different professions. Our findings are helpful for the development of advanced guidance regarding health promotion in hospital workers.

2022 Taiwan lipid guidelines for primary prevention.

Elevated circulating low-density lipoprotein cholesterol (LDL-C) is a major risk factor of atherosclerotic cardiovascular disease (ASCVD). Early control of LDL-C to prevent ASCVD later in life is important. The Taiwan Society of Lipids and Atherosclerosis in association with the other seven societies developed this new lipid guideline focusing on subjects without clinically significant ASCVD. In this guideline for primary prevention, the recommended LDL-C target is based on risk stratification. A healthy lifestyle with recommendations for foods, dietary supplements and alcohol drinking are described. The pharmacological therapies for LDL-C reduction are recommended. The aim of this guideline is to decrease the risk of ASCVD through adequate control of dyslipidemia in Taiwan.

Multiple Functions of KBP in Neural Development Underlie Brain Anomalies in Goldberg-Shprintzen Syndrome.

Kinesin-binding protein (KBP; KIF1BP; KIAA1279) functions as a regulator for a subset of kinesins, many of which play important roles in neural development. Previous studies have shown that KBP is expressed in nearly all tissue with cytoplasmic localization. Autosomal recessive mutations in KIAA1279 cause a rare neurological disorder, Goldberg-Shprintzen syndrome (GOSHS), characterized by microcephaly, polymicrogyria, intellectual disability, axonal neuropathy, thin corpus callosum and peripheral neuropathy. Most KIAA1279 mutations found in GOSHS patients are homozygous nonsense mutations that result in KBP loss-of-function. However, it is not fully understood how KBP dysfunction causes these defects. Here, we used in utero electroporation (IUE) to express KBP short hairpin RNA (shRNA) with green fluorescent protein (GFP) in neural progenitor cells of embryonic day (E) 14 mice, and collected brain slices at different developmental stages. By immunostaining of neuronal lineage markers, we found that KBP knockdown does not affect the neural differentiation process. However, at 4 days post IUE, many cells were located in the intermediate zone (IZ). Moreover, at postnatal day (P) 6, about one third of the cells, which have become mature neurons, remained ectopically in the white matter (WM), while cells that have reached Layer II/III of the cortex showed impaired dendritic outgrowth and axonal projection. We also found that KBP knockdown induces apoptosis during the postnatal period. Our findings indicate that loss of KBP function leads to defects in neuronal migration, morphogenesis, maturation, and survival, which may be responsible for brain phenotypes observed in GOSHS.

Identification of genes associated with cortical malformation using a transposon-mediated somatic mutagenesis screen in mice.

Mutations in genes involved in the production, migration, or differentiation of cortical neurons often lead to malformations of cortical development (MCDs). However, many genetic mutations involved in MCD pathogenesis remain unidentified. Here we developed a genetic screening paradigm based on transposon-mediated somatic mutagenesis by in utero electroporation and the inability of mutant neuronal precursors to migrate to the cortex and identified 33 candidate MCD genes. Consistent with the screen, several genes have already been implicated in neural development and disorders. Functional disruption of the candidate genes by RNAi or CRISPR/Cas9 causes altered neuronal distributions that resemble human cortical dysplasia. To verify potential clinical relevance of these candidate genes, we analyzed somatic mutations in brain tissue from patients with focal cortical dysplasia and found that mutations are enriched in these candidate genes. These results demonstrate that this approach is able to identify potential mouse genes involved in cortical development and MCD pathogenesis.

Extracellular Acid-Base Balance and Ion Transport Between Body Fluid Compartments.

Clinical assessment of acid-base disorders depends on measurements made in the blood, part of the extracellular compartment. Yet much of the metabolic importance of these disorders concerns intracellular events. Intracellular and interstitial compartment acid-base balance is complex and heterogeneous. This review considers the determinants of the extracellular fluid pH related to the ion transport processes at the interface of cells and the interstitial fluid, and between epithelial cells lining the transcellular contents of the gastrointestinal and urinary tracts that open to the external environment. The generation of acid-base disorders and the associated disruption of electrolyte balance are considered in the context of these membrane transporters. This review suggests a process of internal and external balance for pH regulation, similar to that of potassium. The role of secretory gastrointestinal epithelia and renal epithelia with respect to normal pH homeostasis and clinical disorders are considered. Electroneutrality of electrolytes in the ECF is discussed in the context of reciprocal changes in Cl- or non Cl- anions and [Formula: see text].

Disorders of Acid-Base Balance: New Perspectives.

BACKGROUND: Disorders of acid-base involve the complex interplay of many organ systems including brain, lungs, kidney, and liver. Compensations for acid-base disturbances within the brain are more complete, while limitations of compensations are more apparent for most systemic disorders. However, some of the limitations on compensations are necessary to survival, in that preservation of oxygenation, energy balance, cognition, electrolyte, and fluid balance are connected mechanistically. SUMMARY: This review aims to give new and comprehensive perspective on understanding acid-base balance and identifying associated disorders. All metabolic acid-base disorders can be approached in the context of the relative losses or gains of electrolytes or a change in the anion gap in body fluids. Acid-base and electrolyte balance are connected not only at the cellular level but also in daily clinical practice. Urine chemistry is essential to understanding electrolyte excretion and renal compensations. KEY MESSAGES: Many constructs are helpful to understand acid-base, but these models are not mutually exclusive. Electroneutrality and the close interconnection between electrolyte and acid-base balance are important concepts to apply in acid-base diagnoses. All models have complexity and shortcuts that can help in practice. There is no reason to dismiss any of the present constructs, and there is benefit in a combined approach.

A novel DCX missense mutation in a family with X-linked lissencephaly and subcortical band heterotopia syndrome inherited from a low-level somatic mosaic mother: Genetic and functional studies.

PURPOSE: To study the genetics and functional alteration of a family with X-linked lissencephaly and subcortical band heterotopia. METHODS: Five affected patients (one male with lissencephaly, four female with subcortical band heterotopia) and their relatives were studied. Sanger sequencing of DCX gene, allele specific PCR and molecular inversion probe technique were performed. Mutant and wild type of the gene products, namely doublecortin, were expressed in cells followed by immunostaining to explore the localization of doublecortin and microtubules in cells. In vitro microtubule-binding protein spin-down assay was performed to quantify the binding ability of doublecortin to microtubules. KEY FINDINGS: We identified a novel DCX mutation c.785A > G, p.Asp262Gly that segregated with the affected members of the family. Allele specific PCR and molecular inversion probe technique demonstrated that the asymptomatic female carrier had an 8% mutant allele fraction in DNA derived from peripheral leukocytes. This mother had 7 children, 4 of whom were affected and all four affected siblings carried the mutation. Functional study showed that the mutant doublecortin protein had a significant reduction of its ability to bind microtubules. SIGNIFICANCE: Low level mosaicism could be a cause of inherited risk from asymptomatic parents for DCX related lissencephaly-subcortical band heterotopia spectrum. This is particularly important in terms of genetic counselling for recurrent risk of future pregnancies. The reduced binding affinity of mutant doublecortin may contribute to developmental malformation of the cerebral cortex.

Interaction between salt-inducible kinase 2 and protein phosphatase 2A regulates the activity of calcium/calmodulin-dependent protein kinase I and protein phosphatase methylesterase-1.

Salt-inducible kinase 2 (SIK2) is the only AMP-activated kinase (AMPK) family member known to interact with protein phosphatase 2 (PP2A). However, the functional aspects of this complex are largely unknown. Here we report that the SIK2-PP2A complex preserves both kinase and phosphatase activities. In this capacity,SIK2 attenuates the association of the PP2A repressor, the protein phosphatase methylesterase-1 (PME-1), thus preserving the methylation status of the PP2A catalytic subunit. Furthermore, the SIK2-PP2A holoenzyme complex dephosphorylates and inactivates Ca2(+)/calmodulin-dependent protein kinase I (CaMKI), an upstream kinase for phosphorylating PME-1/Ser(15). The functionally antagonistic SIK2-PP2A and CaMKI and PME-1 networks thus constitute a negative feedback loop that modulates the phosphatase activity of PP2A. Depletion of SIK2 led to disruption of the SIK2-PP2A complex, activation of CaMKI, and downstream effects, including phosphorylation of HDAC5/Ser(259), sequestration of HDAC5 in the cytoplasm, and activation of myocyte-specific enhancer factor 2C (MEF2C)-mediated gene expression. These results suggest that the SIK2-PP2A complex functions in the regulation of MEF2C-dependent transcription. Furthermore, this study suggests that the tightly linked regulatory loop comprised of the SIK2-PP2A and CaMKI and PME-1 networks may function in fine-tuning cell proliferation and stress response.

Interaction between salt-inducible kinase 2 (SIK2) and p97/valosin-containing protein (VCP) regulates endoplasmic reticulum (ER)-associated protein degradation in mammalian cells.

Salt-inducible kinase 2 (SIK2) is an important regulator of cAMP response element-binding protein-mediated gene expression in various cell types and is the only AMP-activated protein kinase family member known to interact with the p97/valosin-containing protein (VCP) ATPase. Previously, we have demonstrated that SIK2 can regulate autophagy when proteasomal function is compromised. Here we report that physical and functional interactions between SIK2 and p97/VCP underlie the regulation of endoplasmic reticulum (ER)-associated protein degradation (ERAD). SIK2 co-localizes with p97/VCP in the ER membrane and stimulates its ATPase activity through direct phosphorylation. Although the expression of wild-type recombinant SIK2 accelerated the degradation and removal of ERAD substrates, the kinase-deficient variant conversely had no effect. Furthermore, down-regulation of endogenous SIK2 or mutation of the SIK2 target site on p97/VCP led to impaired degradation of ERAD substrates and disruption of ER homeostasis. Collectively, these findings highlight a mechanism by which the interplay between SIK2 and p97/VCP contributes to the regulation of ERAD in mammalian cells.

Reversible acetylation regulates salt-inducible kinase (SIK2) and its function in autophagy.

Salt-inducible kinase 2 (SIK2) is a serine/threonine protein kinase belonging to the AMP-activated protein kinase (AMPK) family. SIK2 has been shown to function in the insulin-signaling pathway during adipocyte differentiation and to modulate CREB-mediated gene expression in response to hormones and nutrients. However, molecular mechanisms underlying the regulation of SIK2 kinase activity remains largely elusive. Here we report a dynamic, post-translational regulation of its kinase activity that is coordinated by an acetylation-deacetylation switch, p300/CBP-mediated Lys-53 acetylation inhibits SIK2 kinase activity, whereas HDAC6-mediated deacetylation restores the activity. Interestingly, overexpression of acetylation-mimetic mutant of SIK2 (SIK2-K53Q), but not the nonacetylatable K53R variant, resulted in accumulation of autophagosomes. Further consistent with a role in autophagy, knockdown of SIK2 abrogated autophagosome and lysosome fusion. Consequently, SIK2 and its kinase activity are indispensable for the removal of TDP-43Δ inclusion bodies. Our findings uncover SIK2 as a critical determinant in autophagy progression and further suggest a mechanism in which the interplay among kinase and deacetylase activities contributes to cellular protein pool homeostasis.

Extremely high inhibition activity of photoluminescent carbon nanodots toward cancer cells.

Highly water-soluble, biocompatible, and photoluminescent carbon nanodots (C-dots) having an average diameter 3.4 ± 0.8 nm and a quantum yield 4.3% are obtained from used green tea through grinding, calcination and centrifugation. The as-prepared C-dots are stable in high-ionic-strength media (e.g. 500 mM NaCl) and under light irradiation, allowing images of MCF-10A, MCF-7 and MDA-MB-231 cells to be recorded. The C-dots are mostly localized in the cell membranes and cytoplasms, with evidence of excitation-wavelength cell images. Relative to catechin, the C-dots provide greater inhibition efficiency of the growth of MCF-7 and MDA-MB-231 cancer cells, with lower toxicity for the MCF-10A normal cells. The inhibitory activity of C-dots is associated with the generation of greater amounts of reactive oxygen species. A prothrombin time (PT) assay of plasma samples reveals excellent biocompatibility of the C-dots. To the best of our knowledge, for the first time the C-dots provide inhibition efficiencies up to 80% and 82% for MCF-7 and MDA-MB-231 cancer cells, respectively, showing their high potential as cancer inhibitors.

Ag/Au bi-metallic film based color surface plasmon resonance biosensor with enhanced sensitivity, color contrast and great linearity.

In wavelength surface plasmon resonance (SPR) biosensor, the manipulation of SPR dispersion relation by Ag/Au bi-metallic film was first time implemented. Due to the enhanced resonant wavelength shift and the sharper SPR slope of using Ag/Au bi-metallic film, the illuminated color of reflection shows one order of magnitude greater contrast than conventional SPR biosensors. Such an Ag/Au bi-metallic film based color SPR biosensor (CSPRB) allows the detail bio-interactions, for example 100 nM streptavidin, to be distinguished by directly observing the color change of reflection through naked eyes rather than the analysis of spectrometer. In addition to the enhanced sensitivity and color contrast, this CSPRB also possesses a great linear detection range up to 0.0254 RIU, which leading to the application of point-of-care tests.

Antibacterial activities of tellurium nanomaterials.

We prepared four differently shaped Te nanomaterials (NMs) as antibacterial reagents against Escherichia coli. By controlling the concentrations of hydrazine (N(2)H(4)) as reducing agent, NaCl, and temperature, we prepared Te nanowires, nanopencils, nanorices, and nanocubes. These four Te NMs resulted in a live/dead ratio of E. coli cells of less than 0.1, which is smaller than that of Ag nanoparticles. The order of antibacterial activity against E. coli is nanocubes ≈ nanorices > nanopencils ≈ nanowires. This is in good agreement with the concentration order of tellurite (TeO(3)(2-)) ions released from Te NMs in E. coli cells, revealing that TeO(3)(2-) ions account for the antibacterial activity of the four Te NMs. We found that spherical Te nanoparticles (32 nm in diameter) with TeO(3)(2-) ions were formed in the E. coli cells. Compared to Ag nanoparticles that are commonly used as antibacterial reagents, Te NMs have higher antibacterial activity and lower toxicity. Thus, Te NMs hold great practical potential as a new and efficient antibacterial agent.

Using rhodamine 6G-modified gold nanoparticles to detect organic mercury species in highly saline solutions.

We developed a gold nanoparticle (Au NP)-based fluorescence sensor for the detection of mercury ions in aqueous solutions. After introducing bovine serum albumin (BSA) to a solution of rhodamine 6G (R6G) and 3-mercaptopropionic acid (MPA)-modified Au NPs, the as-prepared BSA@R6G/MPA-Au NP probe could sense mercury ions under high salt conditions. This probe operated through a mechanism involving mercury species depositing onto the surfaces of the Au NPs and releasing R6G molecules into the solution, causing the fluorescence intensity of the BSA@R6G/MPA-AuNP solution to increase. We improved the selectivity of the nanosensor by adding masking agents (ethylenediamine tetraacetic acid (EDTA) and Na2S) or tellurium nanowires (Te NWs) to the sample solutions. In the presence of 1.0 mM EDTA and 10 µM Na2S, the selectivities of this system toward phenylmercury (PhHg(I)) over other metal ions and mercury species were greater than 200- and 10-fold, respectively. The limit of detection (LOD), at a signal-to-noise ratio of 3, for PhHg(I) was 20 nM. Selective detection of the total organic mercury (methylmercury (MeHg(I)), ethylmercury (EtHg(I)), and PhHg(I)) was possible when using the BSA@R6G/MPA-Au NPs in conjunction with Te NWs (3.0 nM). The selectivity of this nanosensor system for the total organic mercury over Hg(II) was remarkably high (100-fold) with an LOD for organic mercury of 10 nM. We also demonstrated the feasibility of using the developed nanosensor for rapid determination of mercury species in river, sea, and tap water as well as in fish samples.

Gold nanoparticle-based colorimetric assays for coagulation-related proteins and their inhibition reactions.

In this paper, we describe two simple, label-free, homogenous assays using gold nanoparticles (Au NPs)-one to detect coagulation-related proteins and the other to screen inhibition reactions. The first nanosensor functions on the basis of the fact that thrombin catalyzes fibrinogen to form long-chain fibrins, which then induce aggregation of Au NPs. We applied this sensor to study the interactions of thrombin, inhibitors, cofactors, and antidotes. We further used thrombin-conjugated Au NPs (Thr-Au NPs) to analyze the levels of fibrinogen in plasma samples via fibrinogen-induced aggregation of Thr-Au NPs. The limit of detection (LOD; S/N=3) of this sensor for fibrinogen in plasma was 10nM. The Thr-Au NP probe provided quantitative results for fibrinogen in plasma samples that correlated (R(2)=0.97) with those obtained using a clinical von Clauss clotting rate assay. In addition, the Thr-Au NP-based sensor could be used to monitor thrombin concentrations in plasma samples under physiological conditions. Compared with conventional assays, these label-free assays offer several advantages, such as rapid and simple readout by the naked eye or by UV-vis absorption spectroscopy.