Anticonvulsant effect of equilibrative nucleoside transporters 1 inhibitor in a mouse model of Dravet syndrome.

There are limited therapeutic options for patients with Dravet syndrome (DS). The equilibrative nucleoside transporters 1 (ENT1) mediate both the influx and efflux of adenosine across the cell membrane exerted beneficial effects in the treatment of epilepsy. This study aimed to evaluate the anticonvulsant effect of the ENT1 inhibitor in an animal model of DS (Scn1aE1099X/+ mice). J7 (5 mg/kg) treatment was efficacious in elevating seizure threshold in Scn1aE1099X/+ mice after hyperthermia exposure. Moreover, the J7 treatment significantly reduced the frequency of spontaneous excitatory post-synaptic currents (sEPSCs, ~35% reduction) without affecting the amplitude in dentate gyrus (DG) granule cells. Pretreatment with the adenosine A1 receptor (A1R) antagonist, DPCPX, abolished the J7 effects on sEPSCs. These observations suggest that the J7 shows an anticonvulsant effect in hyperthermia-induced seizures in Scn1aE1099X/+ mice. This effect possibly acts on presynaptic A1R-mediated signaling modulation in granule cells.

Ten existing osteoporosis prediction tools for the successful application of National Health Insurance-reimbursed anti-osteoporosis medications in long-term care residents in Taiwan.

BACKGROUND/PURPOSE: Osteoporotic fracture introduce enormous societal and economic burden, especially for long-term care residents (LTCRs). Although osteoporosis prevention for LTCRs is urgently needed, obstacles such as frail status and inconvenient hospital visits hurdled them from necessary examinations and diagnoses. We aimed to test 10 existing osteoporosis screening tools (OSTs), which can be easily used in institutions and serve as a prediction, for accurately determining the outcome of a Taiwan's National Health Insurance (NHI)-reimbursed anti-osteoporosis medications (AOMs) application for LTCRs. METHODS: This prospective analysis recruited 444 patients from LTC institutions between October 2018 and November 2019. Predictions of whether the NHI-reimbursed AOMs criteria was met were tested for 10 OSTs. The results of OSTs categorized into self-reported or validated based on previous fracture history were self-reported by LTCRs or validated by imaging data and medical records, respectively. The receiver operating characteristic curve and the optimal cut-off points for LTCRs based on Youden's index were explored. RESULTS: Overall, the validated OSTs had a higher positive predictive value (PPV) and negative predictive value (NPV) summation than the corresponding reported OSTs. The validated FRAX-Major was the best OST (PPV = 63.6%, NPV = 82.4% for the male group and, PPV = 78.8%, NPV = 90.0% for the female group). After applying the optimum cut-off derived from Youden's index, the validated FRAX-Major (PPV = 75.4%, NPV = 92.0%)) remained performed best for men. In female population, validated FRAX-Major (PPV = 87.2%, NPV = 84.1%) and validated osteoporosis prescreening risk assessment (OPERA; PPV = 96.1%, NPV = 79.7%)) both provided good prediction results. CONCLUSION: FRAX-Major and OPERA have better prediction ability for LTCRs to acquire NHI-reimbursed AOMs. The validated fracture history and adjusted cut-off points could prominently increase the PPV during prediction.

The psychopathology and happiness of the older adults in Yunlin, Taiwan: What do we need for long-term care service?

BACKGROUND: The purpose of this study was to investigate the psychopathology and level of happiness and their association with the demographic data of the older population in long-term care situations in Taiwan. METHODS: The study enrolled 500 participants who were the elderly in long-term care situations and used the Brief Symptom Rating Scale (BSRS-5) and Chinese Happiness Inventory (CHI) to determine the psychopathology and level of happiness. Multiple linear regression analysis (using a stepwise method) and a two-step cluster analysis were performed to examine the data. RESULTS: The results revealed mean scores for total CHI and total BSRS-5 of 16.08 and 2.34, respectively. Regular exercise habits, higher living expense and having a job were positively associated with happiness. Being older and living in an apartment/condominium were factors negatively associated with happiness. Living in an apartment/condominium was positively associated with a higher BSRS-5 score. Four clusters were grouped according to the variables that contributed the most: housing, exercise habits, living expense and working status. The cluster with no work, no exercise habits and lower living expense had the highest BSRS-5 score and the lowest CHI score. CONCLUSION: We concluded that the association between demographic data and happiness is stronger than the association between demographic data and psychopathology in a community sample in Taiwan. Those who have steady work, higher living expense and regular exercise habits have better happiness and less psychopathology.

A proactive remote pharmaceutical care for rural elderly population: The Houston-Apollo polypharmacy project.

AIMS: To evaluate polypharmacy-related problems in the elderly people who live in rural through a proactive pharmaceutical care project under a novel remote medical service infrastructure (the Houston-Apollo polypharmacy project). METHODS: It is a prospectively cross-sectional study. The elderly aged 65 years old lived in communities executed the congregate meal service and joined the Houston-Apollo project were included. During March and July on 2020, the pharmaceutical care team of Houston-Apollo polypharmacy project interviewed old people and collected their medications by remote video. Polypharmacy situation and drug-related problems, including potentially inappropriate medications (PIMs), anticholinergic burden (ACB) and risk of sarcopaenia, were evaluated by clinical pharmacists. In addition, we analysed the categories of the prescription types between polypharmacy and non-polypharmacy users, polypharmacy users with and without PIMs or ACB. A patient-specific integrated pharmacist's note for medication education and a dear doctor letter (as needed) were generated and delivered within 2-weeks postinterviewed. Age- and sex-adjusted logistic regression model was used to evaluate the association between polypharmacy and these potential medication problems. RESULTS: There were 87 older people (mean age = 75.9) and 536 long-term medications were collected. Among them, 52% were defined as polypharmacy users. Polypharmacy was significantly associated with higher risk of PIMs and ACB. The adjusted odd ratio was 5.31 (95% CI: 2.02-13.9) and 10.1 (95% CI: 3.4-29.7), respectively. Among polypharmacy users, there were nearly double the prescriptions for the nervous system and musculoskeletal system among patients with PIMs compared with those without PIMs. Besides, polypharmacy users with ACB showed higher rate of prescriptions for the nervous system and the alimentary tract and metabolism system compared with those without ACB. CONCLUSION: Polypharmacy was significantly associated with negative impact of medication safety among the elderly people in rural area. A persistent remote pharmaceutical care intervention was crucial for improving this problem.

Differential protective effects of connective tissue growth factor against Aß neurotoxicity on neurons and glia.

Impaired clearance of amyloid-ß peptide (Aß) leads to abnormal extracellular accumulation of this neurotoxic protein that drives neurodegeneration in sporadic Alzheimer's disease (AD). Connective tissue growth factor (CTGF/CCN2) expression is elevated in plaque-surrounding astrocytes in AD patients. However, the role of CTGF in AD pathogenesis remains unclear. Here we characterized the neuroprotective activity of CTGF. We found that CTGF facilitated Aß uptake and subsequent degradation within primary glia and neuroblastoma cells. CTGF enhanced extracellular Aß degradation via membrane-bound matrix metalloproteinase-14 (MMP14) in glia and extracellular MMP13 in neurons. In the brain of a Drosophila AD model, glial-expression of CTGF reduced Aß deposits, improved locomotor function, and rescued memory deficits. Neuroprotective potential of CTGF against Aß42-induced photoreceptor degeneration was disrupted through silencing MMPs. Therefore, CTGF may represent a node for potential AD therapeutics as it intervenes in glia-neuron communication via specific MMPs to alleviate Aß neurotoxicity in the central nervous system.

Low ambient temperature as the only meteorological risk factor of seizure occurrence: A multivariate study.

BACKGROUND: The onset of epileptic seizures is influenced by weather, which is multifactorial. It is unknown which specific weather factors affect the occurrence of seizures. OBJECTIVES: We studied the correlation between the onset of epileptic seizures and multiple weather parameters based on a population-based registry profile. METHODS: We determined the number of patients who visited emergency services in Taiwan diagnosed as having epilepsy. Then we used a linear regression model to analyze the monthly average number of patients who received emergency treatment for epilepsy in relation to temperature, barometric pressure, accumulated precipitation, relative humidity, and hours of sunshine. The Poisson regression model was used to analyze multiple meteorological factors in relation to the number of daily emergency visits because of epilepsy. A receiver operating characteristic curve was used to determine the cutoff temperature for the occurrence of seizures. RESULTS: Temperature appeared to be the robust factor for the onset of epilepsy. For every 1 °C decrease in temperature, there was a relative risk increase of 1.016 in the number of emergency visits as a result of epilepsy. Temperature lower than 18 °C had the best predictive value for seizure. Barometric pressure, accumulated precipitation, relative humidity, and the number of hours of sunshine were not related to the occurrence of seizures. SIGNIFICANCE: Our results suggest that temperature is the only influential meteorological factor that affects seizure occurrence.

The Penetration Depth for Hanatoxin Partitioning into the Membrane Hydrocarbon Core Measured with Neutron Reflectivity.

Hanatoxin (HaTx) from spider venom works as an inhibitor of Kv2.1 channels, most likely by interacting with the voltage sensor (VS). However, the way in which this water-soluble peptide modifies the gating remains poorly understood as the VS is deeply embedded within the bilayer, although it would change its position depending on the membrane potential. To determine whether HaTx can indeed bind to the VS, the depth at which HaTx penetrates into the POPC membranes was measured with neutron reflectivity. Our results successfully demonstrate that HaTx penetrates into the membrane hydrocarbon core (∼9 Šfrom the membrane surface), not lying on the membrane-water interface as reported for another voltage sensor toxin (VSTx). This difference in penetration depth suggests that the two toxins fix the voltage sensors at different positions with respect to the membrane normal, thereby explaining their different inhibitory effects on the channels. In particular, results from MD simulations constrained by our penetration data clearly demonstrate an appropriate orientation for HaTx to interact with the membranes, which is in line with the biochemical information derived from stopped-flow analysis through delineation of the toxin-VS binding interface.

The critical role of Nramp1 in degrading α-synuclein oligomers in microglia under iron overload condition.

Oligomeric α-synuclein is a key mediator in the pathogenesis of Parkinson's disease (PD) and is mainly cleared by autophagy-lysosomal pathway, whose dysfunction results in the accumulation and cell-to-cell transmission of α-synuclein. In this study, concomitant with the accumulation of iron and oligomeric α-synuclein, higher expression of a lysosomal iron transporter, natural resistance-associated macrophage protein-1 (Nramp1), was observed in microglia in post-mortem striatum of sporadic PD patients. Using Nramp1-deficient macrophage (RAW264.7) and microglial (BV-2) cells as in-vitro models, iron exposure significantly reduced the degradation rate of the administered human α-synuclein oligomers, which can be restored by the expression of the wild-type, but not mutant (D543N), Nramp1. Likewise, under iron overload condition, mice with functional Nramp1 (DBA/2 and C57BL/6 congenic mice carrying functional Nramp1) had a better ability to degrade infused human α-synuclein oligomers than mice with nonfunctional Nramp1 (C57BL/6) in the brain and microglia. The interplay between iron and Nramp1 exhibited parallel effects on the clearance of α-synuclein and the activity of lysosomal cathepsin D in vitro and in vivo. Collectively, these findings suggest that the function of Nramp1 contributes to microglial degradation of oligomeric α-synuclein under iron overload condition and may be implicated in the pathogenesis of PD.

Hanatoxin inserts into phospholipid membranes without pore formation.

Hanatoxin (HaTx), a 35-residue polypeptide from spider venom, functions as an inhibitor of Kv2.1 channels by interacting with phospholipids prior to affecting the voltage-sensor. However, how this water-soluble peptide modifies the gating remains poorly understood, as the voltage-sensor is deeply embedded within the bilayer. To determine how HaTx interacts with phospholipid bilayers, in this study, we examined the toxin-induced partitioning of liposomal membranes. HPLC-results from high-speed spin-down vesicles with HaTx demonstrated direct binding. Dynamic light scattering (DLS) and leakage assay results further indicated that neither membrane pores nor membrane fragmentations were observed in the presence of HaTx. To clarify the binding details, Langmuir trough experiments were performed with phospholipid monolayers by mimicking the external leaflet of membrane bilayers, indicating the involvement of acyl chains in such interactions between HaTx and phospholipids. Our current study thus describes the interaction pattern of HaTx with vesicle membranes, defining a membrane-partitioning mechanism for peptide insertion involving the membrane hydrocarbon core without pore formation.

Measurement of Hanatoxin-Induced Membrane Thinning with Lamellar X-ray Diffraction.

Membrane perturbation induced by cysteine-rich peptides is a crucial biological phenomenon but scarcely investigated, in particular with effective biophysical-chemical methodologies. Hanatoxin (HaTx), a 35-residue polypeptide from spider venom, works as an inhibitor of drk1 (Kv2.1) channels, most likely by interacting with the voltage-sensor. However, how this water-soluble peptide modifies the gating remains poorly understood, as the voltage sensor was proposed to be deeply embedded within the bilayer. To see how HaTx interacts with phospholipid bilayers, we observe the toxin-induced perturbation on POPC/DOPG-membranes through measurements of the change in membrane thickness. Lamellar X-ray diffraction (LXD) was applied on stacked planar bilayers in the near-fully hydrated state. The results provide quantitative evidence for the membrane thinning in a concentration-dependent manner, leading to novel and direct combinatory approaches by discovering how to investigate such a biologically relevant interaction between gating-modifier toxins and phospholipid bilayers.

Non-basic amino acids in the ROMK1 channels via an appropriate distance modulate PIP2 regulated pHi-gating.

The ROMK1 (Kir1.1) channel activity is predominantly regulated by intracellular pH (pHi) and phosphatidylinositol 4,5-bisphosphate (PIP2). Although several residues were reported to be involved in the regulation of pHi associated with PIP2 interaction, the detailed molecular mechanism remains unclear. We perform experiments in ROMK1 pHi-gating with electrophysiology combined with mutational and structural analysis. In the present study, non basic residues of C-terminal region (S219, N215, I192, L216 and L220) in ROMK1 channels have been found to mediate channel-PIP2 interaction and pHi gating. Further, our structural results show these residues with an appropriate distance to interact with membrane PIP2. Meanwhile, a cluster of basic residues (R188, R217 and K218), which was previously discovered regarding the interaction with PIP2, exists in this appropriate distance to discriminate the regulation of channel-PIP2 interaction and pHi-gating. This appropriate distance can be observed with high conservation in the Kir channel family. Our results provide insight that an appropriate distance cooperates with the electrostatics interaction of channel-PIP2 to regulate pHi-gating.

Growth hormone is increased in the lungs and enhances experimental lung metastasis of melanoma in DJ-1 KO mice.

BACKGROUND: Growth hormone (GH) mainly serves an endocrine function to regulate somatic growth, but also serves an autocrine function in lung growth and pulmonary function. Several recent studies have demonstrated the role of autocrine GH in tumor progression in some organs. However, it is not clear whether excessive secretion of GH in the lungs is related to pulmonary nodule formation. METHODS: Firstly, the lung tissues dissected from mice were used for Western blotting and PCR measurement. Secondly, the cultured cells were used for examining effects of GH on B16F10 murine melanoma cells. Thirdly, male C57BL/6 mice were intravenously injected with B16F10 cells and then subcutaneously injected with recombinant GH twice per week for three weeks. Finally, stably transfected pool of B16F10 cells with knockdown of growth hormone receptor (GHR) was used to be injected into mice. RESULTS: We found that expression of GH was elevated in the lungs of DJ-1 knockout (KO) mice. We also examined the effects of GH on the growth of cultured melanoma cells. The results showed that GH increased proliferation, colony formation, and invasive capacity of B16F10 cells. In addition, GH also increased the expression of matrix metalloproteinases (MMPs) in B16F10 cells. Administration of GH in vivo enhanced lung nodule formation in C57/B6 mice. Increased lung nodule formation in DJ-1 KO mice following intravenous injection of melanoma cells was inhibited by GHR knockdown in B16F10 cells. CONCLUSIONS: These results indicate that up-regulation of GH in the lungs of DJ-1 KO mice may enhance the malignancy of B16F10 cells and nodule formation in pulmonary metastasis of melanoma.

Functional and structural deficits of the dentate gyrus network coincide with emerging spontaneous seizures in an Scn1a mutant Dravet Syndrome model during development.

Dravet syndrome (DS) is characterized by severe infant-onset myoclonic epilepsy along with delayed psychomotor development and heightened premature mortality. A primary monogenic cause is mutation of the SCN1A gene, which encodes the voltage-gated sodium channel subunit Nav1.1. The nature and timing of changes caused by SCN1A mutation in the hippocampal dentate gyrus (DG) network, a core area for gating major excitatory input to hippocampus and a classic epileptogenic zone, are not well known. In particularly, it is still not clear whether the developmental deficit of this epileptogenic neural network temporally matches with the progress of seizure development. Here, we investigated the emerging functional and structural deficits of the DG network in a novel mouse model (Scn1a(E1099X/+)) that mimics the genetic deficit of human DS. Scn1a(E1099X/+) (Het) mice, similarly to human DS patients, exhibited early spontaneous seizures and were more susceptible to hyperthermia-induced seizures starting at postnatal week (PW) 3, with seizures peaking at PW4. During the same period, the Het DG exhibited a greater reduction of Nav1.1-expressing GABAergic neurons compared to other hippocampal areas. Het DG GABAergic neurons showed altered action potential kinetics, reduced excitability, and generated fewer spontaneous inhibitory inputs into DG granule cells. The effect of reduced inhibitory input to DG granule cells was exacerbated by heightened spontaneous excitatory transmission and elevated excitatory release probability in these cells. In addition to electrophysiological deficit, we observed emerging morphological abnormalities of DG granule cells. Het granule cells exhibited progressively reduced dendritic arborization and excessive spines, which coincided with imbalanced network activity and the developmental onset of spontaneous seizures. Taken together, our results establish the existence of significant structural and functional developmental deficits of the DG network and the temporal correlation between emergence of these deficits and the onset of seizures in Het animals. Most importantly, our results uncover the developmental deficits of neural connectivity in Het mice. Such structural abnormalities likely further exacerbate network instability and compromise higher-order cognitive processing later in development, and thus highlight the multifaceted impacts of Scn1a deficiency on neural development.

Combining the AD8 and MMSE for community-based dementia screening.

BACKGROUND: This study aimed to determine whether a cognitive test the Mini-Mental State Examination (MMSE) and the Ascertain Dementia 8 (AD8) instrument applied in combination could improve the accuracy of dementia detection in a community setting. METHODS: Study participants were recruited from a community-based integrated screening program in Tainan, Taiwan. Participants completed the AD8 and were administered the Chinese version of the MMSE by psychologists. In addition, the presence of dementia was determined by neurologists based on the 2011 National Institute on Aging-Alzheimer's Association guidelines. Logistic regression analysis determined whether the combination of these two tests provided any additional information for dementia detection than either test alone. Receiver operating characteristic (ROC) curve analyses were conducted to explore the performances of different screening modalities in detecting dementia. RESULT: In total, 282 participants with an average age of 69.31 ± 10.27 years were enrolled. The prevalence of dementia among participants aged ≥65 years was 9.29 %. The sensitivity and specificity of the AD8 applied alone for detecting dementia were 64.71 % and 87.89 %, respectively, and of the MMSE applied alone, after adjusting for education level, were 41.18 % and 84.50 %, respectively. Using a cutoff score of 21 for the MMSE resulted in sensitivity of 77.78 % and specificity of 73.58 %. The AD8 and MMSE when combined in parallel yielded 88.89 % sensitivity and 70.16 % specificity. The serial use of the AD8 followed by the MMSE yielded 50 % sensitivity and 93.02 % specificity. Except for when an MMSE cutoff value of 26 was applied, the sensitivity of all examined modalities was poor and specificity was moderate for detecting mild cognitive impairment. ROC curve analysis revealed that the parallel application of the MMSE and AD8 (area under the ROC curve [AUC]: 82.3 % [75.1 %-89.4 %]) resulted in better dementia detection accuracy than the AD8 alone (AUC: 73.3 % [60.7 %-85.9 %]), the MMSE alone (AUC: 77.4 % [67.6 %-87.3 %]), or serial test administration (AUC: 67.6 % [53.4 %-81.8 %]). CONCLUSION: This study successfully demonstrated that the MMSE and AD8 combination for dementia screening could improve detection accuracy in a community setting.

Theory of mind in patients with temporal lobe epilepsy.

Theory of mind (ToM) is a crucial aspect of social cognition and is mediated by a complex neural network. Studies on temporal lobe epilepsy (TLE) suggest that its neuropathological involvement includes several brain regions. Some regions seem to overlap the neural network responsible for ToM, and this overlap provides an opportunity to explore ToM in TLE patients. Another concern is psychosocial problems in TLE, and the study of ToM in TLE could serve as a basis for further understanding the nature of such psychosocial disturbances. Studies on whether TLE patients evidence ToM deficit, however, are scant and controversial. Consequently, we examine whether ToM deficit is evident in TLE. Thirty-one TLE patients and 24 matched controls were recruited and completed four tasks measuring different levels of ToM: false belief, faux pas recognition, processing of implied meanings, and cartoon ToM. The patients were impaired in both basic and advanced ToM. Right TLE had a more wide-ranging picture of deficit than left TLE. ToM appears to be vulnerable to TLE, especially on the right side. Since ToM might contribute to patients' psychosocial adjustment, we thus suggest that a ToM measure be included in regular neuropsychological assessments of such patients.

Geographic variation in the age- and gender-specific prevalence and incidence of epilepsy: analysis of Taiwanese National Health Insurance-based data.

PURPOSE: We studied geographic variation in age- and gender-specific prevalence and incidence of epilepsy in four different areas of Taiwan. METHODS: By using large-scale, National Health Insurance (NHI)-based data from 2000-2003 in Taiwan, we identified 131,287 patients diagnosed with epilepsy (ICD code 345) receiving at least of one of 11 antiepileptic drugs (AEDs). Information on age, gender, and location were also collected. The multivariable Poisson regression analysis was used to assess the heterogeneity of the morbidity of epilepsy in different regions. External data validation was also performed to assess the accuracy of capturing epilepsy cases through our NHI data set. KEY FINDINGS: The age-adjusted prevalence and incidence of epilepsy were 5.85 (per 1,000) between 2000 and 2003 and 97 (per 100,000 person-years) during the follow-up time from 2001 to 2003 in Taiwan. The sensitivity and specificity of ICD-9 coding for epilepsy in the NHI data set were 83.91% and 99.83%, respectively, resulting in a slight overestimation. Male patients had a higher probability of having epilepsy than did females. East Taiwan had significantly higher prevalence and incidence than did other areas. The age-specific incidence pattern in east Taiwan was atypical in that it revealed clustering in young and middle-aged groups. SIGNIFICANCE: Our study demonstrated geographic variation in epidemiologic patterns of epilepsy within Taiwan. The findings are informative and provide insight into the clinical management of epilepsy based on consideration of different target groups in different areas.

Cost-effectiveness of the add-on exenatide to conventional treatment in patients with Parkinson's disease when considering the coexisting effects of diabetes mellitus.

OBJECTIVE: This study aims to investigate the cost-effectiveness of the add-on exenatide to conventional pharmacotherapy in patients with Parkinson's disease (PD) when considering the coexistence of diabetes mellitus (DM). METHODS: We used the Keelung and Community-based Integrated Screening databases to understand the medical utilisation in the Hoehn and Yahr stages of patients with PD. A Markov model with 1-year cycle length and 50-year time horizon was used to assess the cost-effectiveness of add-on exenatide to conventional pharmacotherapy compared to conventional pharmacotherapy alone. All costs were adjusted to the value of the new Taiwanese dollar (NT$) as of the year 2020. One-way sensitivity and probability analyses were performed to test the robustness of the results. RESULTS: From a societal perspective, the add-on exenatide brought an average of 0.39 quality-adjusted life years (QALYs) gained, and a cost increment of NT$104,744 per person in a 50-year horizon compared to conventional pharmacotherapy. The incremental cost-effectiveness ratio (ICER) was NT$268,333 per QALY gained. As the ICER was less than the gross domestic product per capita (NT$839,558), the add-on exenatide was considered to be very cost-effective in the two models, according to the World Health Organization recommendation. Add-on exenatide had a 96.9% probability of being cost-effective in patients with PD, and a 100% probability of being cost-effective in patients with PD and DM. CONCLUSION: Add-on exenatide is cost-effective in PD combined with DM. Considering that DM may be a risk factor for neurodegenerative diseases, exenatide provides both clinical benefits and cost-effectiveness when considering both PD and DM.

The impact of active community-based survey on dementia detection ratio in Taiwan: A cohort study with historical control.

Background: Although early dementia detection is crucial to optimize the treatment outcomes and the management of associated symptoms, the published literature is scarce regarding the effectiveness of active screening protocols in enhancing dementia awareness and increasing the rate of early detection. The present study compared the detection ratio of an active community-based survey for dementia detection with the detection ratio of passive screening during routine clinical practice. Data for passive screening were obtained from the National Health Insurance (NHI) system, which was prospectively collected during the period from 2000 to 2003. Design: A population-based cohort study with historical control. Setting: Taiwan. Participants: A total of 183 participants aged 65 years or older were involved in a community-based survey. Data from 1,921,308 subjects aged 65 years or older were retrieved from the NHI system. Measurements: An adjusted detection ratio, defined as a ratio of dementia prevalence to incidence was used. Results: The results showed that the dementia prevalence during the 2000-2003 period was 2.91% in the elderly population, compared with a prevalence of 6.59% when the active survey was conducted. The incidence of dementia in the active survey cohort was 1.83%. Overall, the dementia detection ratio was higher using active surveys [4.23, 95% confidence interval (CI): 2.68-6.69] than using passive detection (1.45, 95% CI: 1.43-1.47) for those aged 65-79 years. Similar findings were observed for those aged 80 years and older. Conclusion: The implementation of an active community-based survey led to a 3-fold increase in the detection rate of early dementia detection compared to passive screening during routine practice.

YC-1, a novel potential anticancer agent, inhibit multidrug-resistant protein via cGMP-dependent pathway.

The aim of the present study was to evaluate the effect of 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1) on multidrug resistance. Expression of human P-glycoprotein was assessed by realtime quantitative RT-PCR and western blot. The efflux function of P-glycoprotein was evaluated by rhodamine 123 accumulation and calcein-AM uptake models. The mechanisms of action of YC-1 on different signaling pathways were studied using series of antagonists and the kinetics was also assessed. Cytotoxicity was evaluated by MTT assay. The results demonstrated that increased intracellular accumulation of rhodamine 123 and increased fluorescence of calcein were observed after YC-1 treatment. Furthermore, increased YC-1 concentration resulted in significant decrease in Vmax while K(M) remained unchanged suggested that YC-1 acted as a noncompetitive inhibitor of P-glycoprotein. Moreover, the inhibition of Pgp efflux function by YC-1 was significantly reversed by NO synthase inhibitor, (L)-NAME, the sGC inhibitor, ODQ, the PKG inhibitor, Rp-8-Br-PET-cGMPS, and the PKG inhibitor KT5823. In addition, ERK kinase inhibitor PD98059 also significantly restored YC-1 inhibited Pgp efflux function. These results indicated that YC-1 inhibited Pgp efflux via the NO-cGMP-PKG-ERK signaling pathway through noncompetitive inhibition. The present study revealed that YC-1 could be a good candidate for development as a MDR modulator.