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BACKGROUND: Oxidative stress results in the production of excess reactive oxygen species (ROS) and triggers hippocampal neuronal damage as well as occupies a key role in the pathological mechanisms of neurodegenerative disorders such as Alzheimer's disease (AD). A recent study confirmed that magnesium had an inhibitory effect against oxidative stress-related malondialdehyde in vitro. However, whether Magnesium-L-threonate (MgT) is capable of suppressing oxidative stress damage in amyloid ß (Aß)25-35-treated HT22 cells and the AD mouse model still remains to be investigated. AIM: To explore the neuroprotective effect of MgT against oxidative stress injury in vitro and in vivo, and investigate the mechanism. METHODS: Aß25-35-induced HT22 cells were preconditioned with MgT for 12 h. APPswe/PS1dE9 (APP/PS1) mice were orally administered with MgT daily for 3 mo. After MgT treatment, the viability of Aß25-35-treated HT22 cells was determined via conducting cell counting kit-8 test and the cognition of APP/PS1 mice was measured through the Morris Water Maze. Flow cytometry experiments were applied to assess the ROS levels of HT22 cells and measure the apoptosis rate of HT22 cells or hippocampal neurons. Expression of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X (Bax), hypoxia-inducible factor (HIF)-1α, NADPH oxidase (NOX) 4, Aß1-42 and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) pathway proteins was quantified by Western blot. RESULTS: In vitro data confirmed that Aß25-35-induced HT22 cells had a significantly lower cell viability, higher ROS level and higher apoptosis rates compared with those of control cells (all P < 0.001). MgT prevented the Aß25-35-triggered oxidative stress damage by elevating viability and decreasing ROS formation and apoptosis of HT22 cells (all P < 0.001). APP/PS1 mice exhibited worse cognitive performance and higher apoptosis rate of hippocampal neurons than wild-type (WT) mice (all P < 0.01). Meanwhile, significant higher expression of Aß1-42 and NOX4 proteins was detected in APP/PS1 mice than those of WT mice (both P < 0.01). MgT also ameliorated the cognitive deficit, suppressed the apoptosis of hippocampal neuron and downregulated the expression of Aß1-42 and NOX4 proteins in APP/PS1 mouse (all P < 0.05). Moreover, MgT intervention significantly downregulated HIF-1α and Bax, upregulated Bcl-2 and activated the PI3K/Akt pathway both in vitro and in vivo (all P < 0.05). CONCLUSION: MgT exhibits neuroprotective effects against oxidative stress and hippocampal neuronal apoptosis in Aß25-35-treated HT22 cells and APP/PS1 mice.
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Neurosurgeons require considerable expertise and practical experience to deal with the critical situations commonly encountered in complex surgical operations such as cerebral cancer; however, trainees in neurosurgery seldom have the opportunity to develop these skills in the operating room. Physical simulators can give trainees the experience they require. In this study, we adopted advanced molding and replication techniques in the fabrication of a physical simulator for use in practicing the removal of cerebral tumors. Our combination of additive manufacturing and molding technology with elastic material casting made it possible to create a simulator that realistically mimics the skull, brain stem, soft brain lobes, and cerebral cancer with cerebral tumors located precisely where they are likely to appear. Multiple and systematic experiments were conducted to prove that the elastic material used herein was appropriated for building professional medical physical simulator. One neurosurgical trainee reported that under the guidance of a senior neurosurgeon, the physical simulator helped to elucidate the overall process of cerebral cancer removal and provided a realistic impression of the tactile feelings involved in craniotomy. The trainee also learned how to make decisions when facing the infiltration of a cerebral tumor into normal brain lobes. Our results demonstrate the efficacy of the proposed physical simulator in preparing trainees for the rigors involved in performing highly delicate surgical operations.
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Despite the increasing health burden of chronic hepatitis B (CHB) in aging populations, little is known about the course of health-related quality of life (HRQoL) changes. We aimed to assess individual-level longitudinal HRQoL changes in elderly patients with CHB and to examine their correlates. A prospective 5.1 years-cohort study was conducted in community-dwelling adults aged 55 years with hepatitis B surface antigen-positive. Participants underwent serial measurement of HRQoL using the short-form (12) health survey version 2. Of 503 participants, 82.7% remained in good physical health throughout the study period, whereas 9.1% had declining physical health and 8.2% were in poor physical health. We likewise identified three trajectories of mental health changes ("good mental health" [86.9%], "declining mental health" [6.8%], and "poor mental health" [6.4%]). Three baseline characteristics were independently associated with a lower likelihood of remaining physically or mentally healthy: sarcopenic obesity (odds ratio [OR] with 95% confidence interval [95% CI] of 7.5 [2.8-20.5] for poor physical health, 3.1 [1.1-8.4] for declining physical health, 4.3 [1.4-13.0] for poor mental health), a higher number of metabolic abnormalities (OR [95% CI] of 3.6 [1.6-8.0] for poor physical health) and depressed mood (OR [95% CI] of 21.7 [5.8-81.0] for poor physical health, 5.3 [1.4-19.9] for declining physical health, 83.1 [19.7-350.2] for poor mental health, 13.6 [2.9-64.8] for declining mental health). In conclusion, in a cohort of elderly patients with CHB, we demonstrated the heterogeneity and nonlinearity of HRQoL changes and their associations with variations in specific extrahepatic organs/systems.
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Gallium (Ga) is one of the intermetallic elements that has been used in cancer treatment for a long time. However, Ga compounds are increasingly being used to make high-speed semiconductors and photoelectric devices. The current work investigated physiological and pathological changes in zebra fish (Danio rerio) exposed to various Ga3+ levels (0.55, 1.5, and 3.85 mg/L) over a 14-day test period. Decreases in oxygen consumption were significant (p < 0.05) for groups exposed to 3.85 Ga3+ mg/L; this was associated with the fusion of zebra fish gills lamellae. Serum biochemical changes (including aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase) were consistent with observations of damage to organelles within the hepatocytes at higher Ga3+ exposure levels (1.5 and 3.85 mg/L) in zebra fish. We propose <0.55 Ga3+ mg/L as a biologically safe concentration that can be used to establish water quality criteria for this teleost model.
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Gálio/efeitos adversos , Brânquias/efeitos dos fármacos , Fígado/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Peixe-Zebra , Alanina Transaminase/análise , Animais , Aspartato Aminotransferases/análise , Brânquias/patologia , Fígado/ultraestrutura , Peixe-Zebra/anatomia & histologiaRESUMO
Lygus hesperus isa key pest of many economically important crops across western North America. Central to many aspects of the lives of these insects is chemical signalling, with identified roles in host plant selection, aggregation and passive mate guarding. The development of novel monitoring and control approaches for this insect will rely on a sound understanding of how these cues are perceived and processed, and their impact on behavior. Towards this end, we investigated allyl isothiocyanate, cinnamaldehyde and citronellal, compounds that are noxious repellents to other insects. We found that L. hesperus avoided areas containing the three compounds and that exposure induced increases in movement velocity and duration in both nymphs and adults. This suggests these compounds may work as repellents. To better understand the underlying physiology of this response, RNA interference by dsRNA injection was used to inhibit the expression of two chemosensory-associated proteins, the odorant receptor co-receptor (Orco) and the transient receptor potential A (TRPA1) channel. While knockdown of Orco did not change the reaction of adult females to citronellal, TRPA1 silencing effectively eliminated the induced increase to movement, suggesting a chemoperceptory role in citronellal detection.
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Heterópteros , Repelentes de Insetos/farmacologia , Receptores Odorantes/genética , Canal de Cátion TRPA1/genética , Acroleína/análogos & derivados , Acroleína/farmacologia , Monoterpenos Acíclicos/farmacologia , Aldeídos/farmacologia , Animais , Genes de Insetos , Heterópteros/efeitos dos fármacos , Heterópteros/fisiologia , Controle de Insetos , Isotiocianatos/farmacologia , Locomoção/efeitos dos fármacos , Ninfa/efeitos dos fármacos , Ninfa/fisiologia , Odorantes , Interferência de RNA , Receptores Odorantes/efeitos dos fármacos , Canal de Cátion TRPA1/efeitos dos fármacosRESUMO
Herein, we report a novel stepwise addition-controlled ring size method, to access tetrahydropyrimidines through an operationally simple [3 + 3] cycloaddition of vinylethylene carbonates with triazinanes. Interestingly, we could also use this method for a [3 + 3] oxidative cycloaddition, which allows the facile synthesis of polysubstituted terphenyls under mild conditions. Mechanistic studies suggest that vinylethylene carbonates could generate α,ß-unsaturated aldehydes as 3-carbon synthons for cycloaddition via a combination process of Pd-catalyzed decarboxylation and ß-H elimination.
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This study was undertaken to assess the effect of blood glucose on BMD and interactions with age, sex, and BMI in a Taiwanese population. Both obese and non-obese people with type 2 diabetes (T2DM) had higher BMD, at lumbar spine and femoral neck, compared with healthy subjects. In addition, the prevalence of osteoporosis significantly decreased with blood sugar and HbA1c. PURPOSE: This study was undertaken to assess the effect of blood glucose on BMD and possible interactions with age, sex, and BMI in a Taiwanese population. PATIENTS AND METHODS: This study was a retrospective cross-sectional study using data from the Health Examination Database of Changhua Christian Hospital. Data on BMD of the lumbar spine and femoral neck were obtained by dual X-ray absorptiometry (DXA), and other relevant clinical and laboratory data were recorded. RESULTS: The type 2 diabetes (T2DM) group had a higher BMD than the controls. When comparing the prevalence of osteoporosis between subjects by glucose and HbA1c level, the prevalence of osteoporosis significantly decreased with blood glucose and HbA1c. In addition, the BMD of the lumbar spine and femoral neck was higher in the T2DM group than in the controls. Osteoporosis was negatively associated with DM, BMI, and drinking, but positively associated with age, female gender, previous fracture history, and other diseases of the musculoskeletal system and connective tissue. The association between diabetes and osteoporosis remained statistically significant after adjusting for the above factors. T2DM was associated with lower odds of osteoporosis in both obese (OR = 0.77) and non-obese (OR = 0.63) (p for interaction = 0.555). CONCLUSIONS: Both obese and non-obese people with T2DM had higher BMD, at lumbar spine and femoral neck, compared with healthy subjects. In addition, the prevalence of osteoporosis significantly decreased with blood glucose and HbA1c.
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Absorciometria de Fóton/estatística & dados numéricos , Glicemia/análise , Densidade Óssea , Diabetes Mellitus Tipo 2/fisiopatologia , Osteoporose/epidemiologia , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Feminino , Colo do Fêmur/diagnóstico por imagem , Hemoglobinas Glicadas/análise , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/complicações , Obesidade/fisiopatologia , Osteoporose/etiologia , Prevalência , Estudos Retrospectivos , Fatores Sexuais , Taiwan/epidemiologiaRESUMO
Bidirectional co-morbidity between migraine and depression has been observed. Mood disorders are associated with an increased risk of both migraine and irritable bowel syndrome (IBS). The aim of this study was to evaluate the risk of developing IBS in patients with migraine and to compare the risks between those with and without anxiety or depression. This research used the data contained in the National Health Insurance Research Database (NHIRD). A total of 2859 subjects with migraine and 5718 age-, sex-, hypertension-, diabetes-, mood disorder-matched controls were identified. Both cohorts excluded subjects with pre-existing catastrophic illness and IBS diagnosed before the index visit or within 30days after the index visit. All individuals of both cohorts were tracked until either having the diagnosis of IBS, loss of follow-up, or IBS free up to 7years. During the 7-year follow-up period, 8.4% of patients with migraine and 5.4% of control cohort developed IBS. Migraine is associated with an increased risk of developing IBS (HR=1.58, 95% CI: 1.33-1.87). When separating the cohort into those with mood disorder and without it, migraine is a significant risk factor of IBS in patients without mood disorders, but not in patients with co-existed mood disorders. The findings of this study suggest that migraine is a risk factor of future IBS development for those without comorbid anxiety or depression. However, migraine does not contribute significantly additional risk to IBS development in patients with comorbid anxiety or depression.
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Ansiedade/epidemiologia , Depressão/epidemiologia , Síndrome do Intestino Irritável/epidemiologia , Transtornos de Enxaqueca/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taiwan/epidemiologia , Adulto JovemRESUMO
In addition to the impact of a disease itself, public reaction could be considered another outbreak to be controlled during an epidemic. Taiwan's experience with SARS in 2003 highlighted the critical role played by the media during crisis communication. After the SARS outbreak, Taiwan's Centers for Disease Control (Taiwan CDC) followed the WHO outbreak communication guidelines on trust, early announcements, transparency, informing the public, and planning, in order to reform its risk communication systems. This article describes the risk communication framework in Taiwan, which has been used to respond to the 2009-2016 influenza epidemics, Ebola in West Africa (2014-16), and MERS-CoV in South Korea (2015) during the post-SARS era. Many communication strategies, ranging from traditional media to social and new media, have been implemented to improve transparency in public communication and promote civic engagement. Taiwan CDC will continue to maintain the strengths of its risk communication systems and resolve challenges as they emerge through active evaluation and monitoring of public opinion to advance Taiwan's capacity in outbreak communication and control. Moreover, Taiwan CDC will continue to implement the IHR (2005) and to promote a global community working together to fight shared risks and to reach the goal of "One World, One Health."
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Comunicação , Surtos de Doenças/prevenção & controle , Meios de Comunicação de Massa/estatística & dados numéricos , Doenças Transmissíveis Emergentes/epidemiologia , Humanos , Risco , Síndrome Respiratória Aguda Grave/epidemiologia , Taiwan/epidemiologiaRESUMO
BACKGROUND: Metabolic syndrome is a worldwide disorder and also the major risk factor of several systemic diseases. Evidence identifying the association between metabolic syndrome and nephrolithiasis is lacking, especially in Taiwan. AIM: The aim of this study was to investigate the association between nephrolithiasis and metabolic syndrome and its components. DESIGN AND SETTING: This was a cross-sectional study conducted in the Health Examination Department of a medical center in Changhua, Taiwan, from January 2010 to December 2010. METHODS: We reviewed the medical records of patients who had visited the Health Examination Center of Changhua Christian Hospital in 2010. A total of 3,886 individuals were enrolled. According to the exclusion criteria, those with an age <20 years and an abnormal renal function were excluded. A total of 3,793 subjects were included. All P-values are two tailed, and P<0.05 was defined as statistically significant. RESULTS: The results showed a correlation between nephrolithiasis and metabolic syndrome and its components. The multivariate-adjusted odds ratio (OR) (95% confidence interval [CI]) of metabolic syndrome for nephrolithiasis was 1.318 (1.083-1.604), with a P-value of 0.006. Larger waist circumference (multivariable-adjusted OR 1.338; 95% CI 1.098-1.631; P=0.004), higher blood pressure (multivariable-adjusted OR 1.333; 95% CI 1.106-1.607; P=0.003), and increased fasting glucose (multivariable-adjusted OR 1.276; 95% CI 1.054-1.546; P=0.01) were associated with nephrolithiasis. CONCLUSION: This is the first study in Taiwan to investigate the relationship between metabolic syndrome and nephrolithiasis. The mechanism is controversial, and several hypotheses are offered. Adequate lifestyle modification and proper treatment in metabolic syndrome management may both contribute to nephrolithiasis prevention.
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The first example of intermolecular amination of unactivated C(sp3 )-H bonds by cyclic alkylamines mediated by Cu(OAc)2 /O2 is reported. This method avoids the use of benzoyloxyamines as the aminating reagent, which are normally prepared from alkylamines in extra steps. A variety of unnatural ß2, 2 -amino acid analogues are synthesized by this simple and efficient procedure. This approach offers a solution to the previous unmet challenge of C(sp3 )-H/N-H activation for the formation of C(sp3 )-N bonds.
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The effects of the spatial arrangement of the conjugated side chains of two-dimensional polymers on their optical, electrochemical, molecular-packing, and photovoltaic characteristics were investigated. Accordingly, novel polythiophenes with horizontally (PBTTTV-h) and vertically (PBTTTV-v) grafted terthiophenevinylene (TTV) conjugated side chains were synthesized that display two and one UV-vis peaks, respectively; the difference is due to the different constitutions of the conjugated side-chains. Because the spatial arrangement affects the molecular self-assembly, PBTTTV-h shows stronger crystallinity than PBTTTV-v, which enhances the charge mobility in devices. Moreover, PBTTTV-h has a lower HOMO energy level (−5.49 eV) than PBTTTV-v (−5.40 eV). Bulk heterojunction solar cells fabricated from PBTTTV-h/PC71BM and PBTTTV-v/PC71BM exhibit power conversion efficiencies of 4.75% and 4.00%, respectively, and Voc values of 800 and 730 mV, respectively, under AM1.5G illumination (100 mW cm(−2)). Thus, the architecture of the TTV conjugated side chains affects the optical, electrochemical, and photovoltaic properties; this study provides more ideas for improving 2-D conjugated polymers for semiconductor devices.
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BACKGROUND: To investigate the association between metabolic syndrome, including its factors, and gallstone disease (GSD) in a Taiwanese population. METHODS: We conducted a cross-sectional study during 2011 ~ 2012. A total of 12050 subjects who completed a questionnaire and underwent physical examination, laboratory tests and abdominal ultrasonography formed the study population. RESULTS: The prevalences of metabolic syndrome and gallstone disease were 24.09% and 6.16%. In an age- and sex-adjusted logistic regression model, metabolic syndrome was associated with gallstone disease (OR = 1.61; P < 0.0001). Age, abdominal obesity, and lower high-density lipoprotein cholesterol were associated with gallstone disease after adjusting for other factors. Females had a higher odds ratio than males in waist circumference for GSD, whereas males had a lower odds ratio than females in HDL-C for GSD. CONCLUSIONS: The present study suggests that metabolic syndrome is related to gallstone disease. Waist circumference and high-density lipoprotein cholesterol are all associated with GSD. Men and women may possibly have different priorities and strategies to reduce the burden of GSD.
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Dislipidemias/epidemiologia , Cálculos Biliares/epidemiologia , Síndrome Metabólica/epidemiologia , Obesidade Abdominal/epidemiologia , Adulto , Fatores Etários , Colelitíase/epidemiologia , HDL-Colesterol/sangue , Estudos Transversais , Dislipidemias/sangue , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Taiwan/epidemiologia , Circunferência da CinturaRESUMO
OBJECTIVE: The present study was to explore signaling mechanisms underlying nicotine-induced inhibition of large-conductance calcium-activated potassium channels (BK(Ca)). METHODS: 8 week male Wistar rats were divided randomly into saline group and nicotine group and received respectively injection with saline or nicotine (Sigma, Shanghai, China) at 2 mg/(kg x d) for 21 days. Coronary vascular smooth muscle cells were dissociated enzymatically. Dissociated smooth muscle cells were interfered with CPT-cAMP (100 micromol/L) or forskolin (10 micromol/L). The signal channel open dwell-time (To), close dwell-time (Tc) and open probability (Po) were recorded. RESULTS: CPT-cAMP or forskolin significantly prolonged To, shorten Tc and increased Po in saline group (P < 0.01). But in nicotine group To, Tc and Po did not been changed. CONCLUSION: This phenomenon may serve as a physiological mechanism that nicotine inhibits BK(Ca) channel activity to increase via cAMP/PKA-dependent pathway.
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Vasos Coronários/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Miócitos de Músculo Liso/metabolismo , Nicotina/farmacologia , Animais , Artérias/citologia , Artérias/efeitos dos fármacos , Artérias/metabolismo , Vasos Coronários/citologia , Vasos Coronários/metabolismo , Masculino , Miócitos de Músculo Liso/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Transdução de SinaisRESUMO
A new oxidation procedure of alkynes catalyzed by Tp(PPh(3))(CH(3)CN)Ru-Cl is presented, which provides an efficient way to obtain alkenyl 1,2-diketones via ruthenium alkenyl 1,2-diketone intermediates. In contrast, the analogous reactions with Tp(PPh(3))(PhCN)Ru-Cl gave rise to the ruthenium metallacycle complexes.
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Alcinos/química , Cetonas/química , Rutênio/química , Carbono/química , Catálise , Cristalografia por Raios X , Cetonas/síntese química , Conformação Molecular , OxirreduçãoRESUMO
Medical images usually suffer from a partial volume effect (PVE), which may degrade the accuracy of any quantitative information extracted from the images. Our aim was to recreate accurate radioactivity concentration and time-activity curves (TACs) by microPET R4 quantification using ensemble learning independent component analysis (EL-ICA). We designed a digital cardiac phantom for this simulation and in order to evaluate the ability of EL-ICA to correct the PVE, the simulated images were convoluted using a Gaussian function (FWHM = 1-4 mm). The robustness of the proposed method towards noise was investigated by adding statistical noise (SNR = 2-16). During further evaluation, another set of cardiac phantoms were generated from the reconstructed images, and Poisson noise at different levels was added to the sinogram. In real experiments, four rat microPET images and a number of arterial blood samples were obtained; these were used to estimate the metabolic rate of FDG (MR(FDG)). Input functions estimated using the FastICA method were used for comparison. The results showed that EL-ICA could correct PVE in both the simulated and real cases. After correcting for the PVE, the errors for MR(FDG), when estimated by the EL-ICA method, were smaller than those when TACs were directly derived from the PET images and when the FastICA approach was used.
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Sangue , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Animais , Artefatos , Coração/diagnóstico por imagem , Imagens de Fantasmas , Ratos , Sensibilidade e EspecificidadeRESUMO
AIM: To investigate the changes of large-conductance calcium-activated potassium channels (BKCa, MaxiK) during aging and relations between the changes and blood pressure. METHODS: Male spontaneously hypertensive rats (SHR) aged 9, 15, 21, 27, 33 weeks (the number of each weeks SHR was 4) were selected as hypertension group rats, corresponding gender, weeks and number Wistar-Kyoto rats (WKY) as control group rats. Blood pressure of abdominalis aorta of each weeks SHR and WKY were measured by BL-420F experimental system of biological function. The arteria mesenteric minor (AMM) were isolated in blunt dissection method. The vascular smooth muscle cells (VSMCs) of AMM were isolated with prolease. The potassium current, the current after BKCa were blockaded by Tetraethylammonium (TEA) and the capacitance of membrane (Cm) of VSMCs of AMM were recorded with using whole cell patch clamp, and calculated the BKCa current and the BKCa current density. Probe the correlation of the changes of BKCa current density with MABP during aging. RESULTS: The potassium current density and BKCa current density of VSMCs of AMM of SHR were decreasing during aging, however, the changes of WKY had no statistically significance (P > 0.05). The BKCa current density was extremely correlative with MABP in SH R (the values of r were -0.7174), in WKY, the BKCa current density was correlative with MAB P r = -0.4832. CONCLUSION: BKCa current and current density attenuate with aging, the level of blood pressure is response of the attenuated degree. The BKCa current density is extremely correlative with the blood pressure.
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Pressão Sanguínea/fisiologia , Hipertensão/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Artérias Mesentéricas/citologia , Músculo Liso Vascular/metabolismo , Canais de Potássio/metabolismo , Envelhecimento/fisiologia , Animais , Membrana Celular/fisiologia , Hipertensão/fisiopatologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta , Canais de Potássio Ativados por Cálcio de Condutância Alta/fisiologia , Masculino , Potenciais da Membrana/fisiologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/fisiologia , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKYRESUMO
The objective of this study is to investigate the effects of respiratory motion (RM) on defect detection in Tc-99m sestamibi myocardial perfusion SPECT (MPS) using a phantom population that includes patient variability. Three RM patterns are included, namely breath-hold, slightly enhanced normal breathing, and deep breathing. For each RM pattern, six 4-D NCAT phantoms were generated, each with anatomical variations. Anterior, lateral and inferior myocardial defects with different sizes and contrasts were inserted. Noise-free SPECT projections were simulated using an analytical projector. Poisson noise was then added to generate noisy realizations. The projection data were reconstructed using the OS-EM algorithm with 1 and 4 subsets/iteration and at 1, 2, 3, 5, 7, and 10 iterations. Short-axis images centered at the centroid of the myocardial defect were extracted, and the channelized Hotelling observer (CHO) was applied for the detection of the defect. The CHO results show that the value of the area under the receiver operating characteristics (ROC) curve (AUC) is affected by the RM amplitude. For all the defect sizes and contrasts studied, the highest or optimal AUC values indicate maximum detectability decrease with the increase of the RM amplitude. With no respiration, the ranking of the optimal AUC value in decreasing order is anterior then lateral, and finally inferior defects. The AUC value of the lateral defect drops more severely as the RM amplitude increases compared to other defect locations. Furthermore, as the RM amplitude increases, the AUC values of the smaller defects drop more quickly than the larger ones. We demonstrated that RM affects defect detectability of MPS imaging. The results indicate that developments of optimal data acquisition methods and RM correction methods are needed to improve the defect detectability in MPS.
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The zinc finger proteins belong to the largest family of regulatory transcription factors, which play an important role in growth and development in animal and plant systems. SUPERMAN-like zinc finger protein gene has only one "finger like" motif. A pair of degenerate primers was designed according to the conserved regions, and 3 kinds of EST of this family were isolated from cotton through RT-PCR. The full length of one SUPERMAN-like zinc finger protein also has been acquired. The entire coding region is 744 bp and encodes a polypeptide of 248 amino acids with 40% homology to RBE protein of Arabidopsis deposited in the GenBank. This gene was designated as GZFP. It has the conserved zinc finger domain and the leucine rich region at the carboxyl terminus but no intron in the coding region. GZFP also has the plant nuclear localization signal. GZFP shows a more expression pattern in floral buds, ovaries, petals and roots than in phloem, xylem, fibers, leaves and seeds of cotton by RT-PCR, although it has a very low detection level and there is not any homologous ESTs found in the GenBank. Analysis of the 5' flanking sequence shows there are several regulatory elements responsible for pollen and root expression, four core sites required for binding of Dof proteins and four light-regulated elements.
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Genoma de Planta , Gossypium/genética , Proteínas de Plantas/genética , Dedos de Zinco/genética , Região 5'-Flanqueadora/genética , Sequência de Aminoácidos , Clonagem Molecular , Expressão Gênica , Genes de Plantas , Gossypium/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/isolamento & purificação , Análise de Sequência de Proteína , Dedos de Zinco/fisiologiaRESUMO
Nigral dopaminergic projections to the striatum are targeted in Parkinson's disease (PD). The extent of the degeneration of the dopaminergic system in PD can be visualised by dopamine transporter imaging using single-photon emission tomography (SPET). In this study in 188 patients with PD, we analysed the image patterns and compared them with the clinical features in order to verify the usefulness of technetium-99m TRODAT-1 brain SPET in the evaluation of patients with PD. Two independent readers visually assessed SPET slices from three brain axes according to a "fine" visual scale; results were also grouped according to a "rough" visual scale. Results of both visual and semi-quantitative analyses were compared among patients with different stages of PD and healthy controls. There was good agreement between the readers in the interpretation of the image patterns [kappa statistic (kappa)=0.85 for the presence of PD; kappa=0.88 for the rough scale and 0.81 for the fine scale]. Good concordance was obtained when visual interpretation was used to evaluate the presence of PD (sensitivity = 98%, specificity = 86%, kappa = 0.85). Semi-quantitative analyses revealed significant negative correlations between both striatal and putaminal uptake and disease severity as assessed using the Hoehn and Yahr scale (rho = -0.89 and -0.93 respectively). An apparent decrease in striatal uptake in early PD, hardly discernible from the uptake level in advanced PD, was commonly found in visual analyses. The results suggest that both visual and semi-quantitative analyses of 99mTc-TRODAT-1 SPET images reflect neurodegeneration in PD, and that 99mTc-TRODAT-1 SPET represents an adequate means for evaluation of the status of patients with PD.