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The interactive effects between electron donor substances and iron (Fe) oxides have significant influence on electron transfer and the growth of Fe-reducing bacteria, which may affect the reductive dechlorination of 1,1,1-trichoro-2,2-bis(p-chlorophenyl)ethane (DDT) in soils. To evaluate the roles of volatile fatty acids and Fe(III) oxide in accelerating the reductive dechlorination of DDT in Hydragric Acrisols, a batch anaerobic incubation experiment was conducted in a slurry system with the following seven treatments: sterile soil, control (DDT-contaminated soil), lactic acid, propionic acid, goethite, lactic acid + goethite, and propionic acid + goethite. Results showed that after 20 d of incubation, DDT residues for these treatments decreased by 34, 65, 77, 81, 77, 90, and 92% of the initial quantities, respectively, with 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethane as the dominant metabolite. The application of lactic acid had no significant effect on DDT dechlorination in the first 8 d while the methanogenesis rate increased quickly but accelerated DDT dechlorination after Day 8 while the methanogenesis rate decreased and Fe(II) contents increased. The application of propionic acid enhanced DDT dechlorination rates throughout the incubation. The amendment by goethite stimulated microbial reduction of Fe(III) oxides to generate Fe(II), which was an efficient electron donor, thus accelerating DDT dechlorination significantly in the early incubation period. A synergetic interaction that accelerated DDT dechlorination, either between lactic acid and goethite or between propionic acid and goethite, was obtained. The results will be of great significance to develop efficient in situ remediation technology of DDT-contaminated soil.
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DDT/química , Compostos Férricos/química , Elétrons , OxirreduçãoRESUMO
The quantitative importance of anaerobic ammonium oxidation (anammox) has been described in paddy fields, while the presence and importance of anammox in subsurface soil from vegetable fields have not been determined yet. Here, we investigated the occurrence and activity of anammox bacteria in five different types of vegetable fields located in Jiangsu Province, China. Stable isotope experiments confirmed the anammox activity in the examined soils, with the potential rates of 2.1 and 23.2 nmol N2 g(-1) dry soil day(-1), and the anammox accounted for 5.9-20.5% of total soil dinitrogen gas production. It is estimated that a total loss of 7.1-78.2 g N m(-2) year(-1) could be linked to the anammox process in the examined vegetable fields. Phylogenetic analyses showed that multiple co-occurring anammox genera were present in the examined soils, including Candidatus Brocadia, Candidatus Kuenenia, Candidatus Anammoxoglobus and Candidatus Jettenia, and Candidatus Brocadia appeared to be the most common anammox genus. Quantitative PCR further confirmed the presence of anammox bacteria in the examined soils, with the abundance varying from 2.8 × 10(5) to 3.0 × 10(6) copies g(-1) dry soil. Correlation analyses suggested that the soil ammonium concentration had significant influence on the activity and abundance of anammox bacteria in the examined soils. The results of our study showed the presence of diverse anammox bacteria and indicated that the anammox process could serve as an important nitrogen loss pathway in vegetable fields.
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Compostos de Amônio/metabolismo , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/metabolismo , Microbiologia do Solo , Verduras/crescimento & desenvolvimento , Anaerobiose , Bactérias Anaeróbias/classificação , China , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Marcação por Isótopo , Dados de Sequência Molecular , Nitrogênio/metabolismo , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNARESUMO
BACKGROUND: Giant congenital biliary dilation (CBD) is a rare condition observed in clinical practice. Infants born with this condition often experience a poor overall health status, and the disease progresses rapidly, leading to severe biliary obstruction, infections, pressure exerted by the enlarged CBD on abdominal organs, disturbances in the internal environment, and multiple organ dysfunction. The treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs, making it difficult to separate the bile duct wall from adjacent tissues or to control bleeding. CASE SUMMARY: Herein, we present the details of an 11-d-old male newborn who was diagnosed with giant CBD. The patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago, and also because the patient had been experiencing yellowish skin for the past 9 d. The abnormal echo in the fetal abdomen was first noticed by the patient's mother during a routine ultrasound examination at a local hospital, when the patient was at 24 wk + 6 d of pregnancy. This finding raised concerns about the possibility of congenital biliary dilatation (22 mm × 21 mm). Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary dilatation. No specific treatment was administered for biliary dilatation during this period. A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis, measuring approximately 9.2 cm × 7.4 cm × 11.3 cm. Based on the scan, it was classified as a type I biliary dilatation. CONCLUSION: The analysis reveals that prenatal imaging techniques, such as ultrasound and magnetic resonance imaging, play a crucial role in the early diagnosis, fetal prognosis, and treatment plan for giant CBD. Laparoscopic surgery for giant CBD presents certain challenges, including difficulties in separating the cyst wall, anastomosis, and hemostasis, as well as severe biliary system infection and ulceration. Consequently, there is a high likelihood of converting to laparotomy. The choice between surgical methods like hepaticojejunostomy (HJ) or hepaticoduodenostomy has not been standardized yet. However, we have achieved favorable outcomes using HJ. Preoperative management of inflammation, biliary drainage, liver function protection, and supportive treatment are particularly vital in improving children's prognosis. After discharge, it is essential to conduct timely reexamination and close follow-up to identify potential complications.
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The Cancer-related Psychological Flexibility Questionnaire (CPFQ) was developed and validated for assessing cancer patients' psychological flexibility, including attitudes and behavior toward cancer. In a systematic process, the CPFQ identified four factors through principal component analysis and confirmatory factor analysis: Cancer Acceptance, Cancer Avoidance, Activity Engagement, and Valued Action. The results of this study reveal that the CPFQ has a clear factor structure and good psychometric properties. The specific nature of cancer and the need for a specific measure of cancer patient psychological flexibility make this questionnaire valuable for research on psychological flexibility in cancer patients.
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BACKGROUND: Magnetic compression anastomosis (MCA) is a novel suture-free reconstruction of the digestive tract. It has been used in gastrointestinal anastomosis, jejunal anastomosis, cholangioenteric anastomosis and so on. The traditional operative outcomes of congenital esophageal atresia and benign esophageal stricture are poor, and there are too many complications postoperatively. AIM: To test MCA technology to reconstruct the esophagus in dogs, prior to studying the feasibility and safety of MCA in humans. METHODS: Thirty-six dogs were randomized into either the study or control group (n = 18 per group). The dogs in the study group were subjected to end-to-end esophageal anastomosis with the magnetic compression device, while those in the control group underwent hand-sewn anastomosis with 4-0 absorbable multifilament Vicryl. We used interrupted single-layer inverting sutures. The anastomosis time, gross appearance, weight and pathology of the anastomosis were evaluated at one month, three months and six months postoperatively. RESULTS: The anastomosis time of the MCA group was shorter than that of the hand-sewn group (7.5 ± 1.0 min vs 12.5 ± 1.8 min, P < 0.01). In the MCA group, X-ray examination was performed every day to locate the magnetic device in the esophagus before the magnetic device fell off from the esophagus. In the hand-sewn group, dogs did not undergo X-ray examination. One month after the surgeries, the mean weight of the dogs in the hand-sewn group had decreased more than that of the dogs in the MCA group (11.63 ± 0.71 kg vs 12.73 ± 0.80 kg, P < 0.05). At 3 mo and 6 mo after the operation, the dogs' weights were similar between the two groups (13.75 ± 0.84 kg vs 14.03 ± 0.82 kg, 14.93 ± 0.80 kg vs 15.44 ± 0.47 kg). The number of inflammatory cells in MCA group was lower than that in hand-sewn group on 1 mo after operation. CONCLUSION: MCA is an effective and safe method for esophageal reconstruction. The anastomosis time of the MCA group was less than that of the hand-sewn group. This study shows that MCA technology may be applied to human esophageal reconstruction, provided these favorable results are confirmed by more publications.
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Estenose Esofágica , Poliglactina 910 , Animais , Cães , Humanos , Anastomose Cirúrgica/efeitos adversos , Estenose Esofágica/etiologia , Estenose Esofágica/cirurgia , Fenômenos MagnéticosRESUMO
BACKGROUND: Cancer-related chronic pain is reported by many patients during treatment. There are very few Chinese tools for measuring psychological inflexibility caused by cancer pain, particularly with regard to psychological processes that might influence pain severity and function disorder during cancer treatment. OBJECTIVE: To culturally adapt the Psychological Inflexibility in Pain Scale (PIPS) to Chinese cancer patients experiencing chronic pain, including the determination of psychometric properties of the translated PIPS. METHODS: This cross-sectional study included 2 phases: (1) translation and cultural adaptation and (2) determination of psychometric properties of the translated PIPS. In total, 389 cancer patients with several types of cancer experiencing chronic pain enrolled from May to September 2018 at a tertiary cancer hospital in Yuelu District of Hunan Province, China. RESULTS: The Chinese PIPS version was semantically equivalent to the original. It had a 2-factor structure with satisfactory content validity (content validity index = 0.78-1.00), convergent and discriminant validity (composite reliability and average variance extracted at 0.41-0.89, P < .001), criterion-related validity (r = 0.54 and 0.41, P < .001), Cronbach's α coefficients (α = .87), and test-retest reliability (0.9 ≤ r ≤ 0.98). CONCLUSIONS: The Chinese PIPS version has been culturally adapted and has strong psychometric properties. The scale is a psychometrically sound assessment of psychological inflexibility that can be used for future studies of pain and pain management for cancer patients. IMPLICATIONS FOR PRACTICE: The study provides a vital tool for the psychological management of cancer patients with chronic pain.
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Dor Crônica/psicologia , Neoplasias/psicologia , Medição da Dor/psicologia , Inquéritos e Questionários/normas , Adaptação Fisiológica , Adulto , China , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/normas , Psicometria , Reprodutibilidade dos Testes , Tradução , TraduçõesRESUMO
BACKGROUND: Periodontitis is a chronic inflammation of periodontal supporting tissue caused by local factors. Periodontal surgery can change the gene expression of peripheral blood mononuclear cells. However, little is known about the potential mechanism of surgical treatment for periodontitis. AIM: To explore the potential molecular mechanism of surgical treatment for periodontitis. METHODS: First, based on the expression profiles of genes related to surgical treatment for periodontitis, a set of expression disorder modules related to surgical treatment for periodontitis were obtained by enrichment analysis. Subsequently, based on crosstalk analysis, we proved that there was a significant crosstalk relationship between module 3 and module 5. Finally, based on predictive analysis of multidimensional regulators, we identified a series of regulatory factors, such as endogenous genes, non-coding RNAs (ncRNAs), and transcription factors, which have potential regulatory effects on periodontitis. RESULTS: A total of 337 genes related to surgical treatment for periodontitis were obtained, and 3896 genes related to periodontitis were amplified. Eight expression modules of periodontitis were obtained, involving the aggregation of 2672 gene modules. These modules are mainly involved in G-protein coupled receptor signaling pathway, coupled to cyclic nucleotide second messenger, and adenylate cyclase-modulating G-protein coupled receptor signaling pathway. In addition, eight endogenous genes (including EGF, RPS27A, and GNB3) were screened by network connectivity analysis. Finally, based on this set of potential dysfunction modules, 94 transcription factors (including NFKB1, SP1, and STAT3) and 1198 ncRNAs (including MALAT1, CRNDE, and ANCR) were revealed. These core regulators are thought to be involved in the potential molecular mechanism of periodontitis after surgical treatment. CONCLUSION: Based on the results of this study, we can show biologists and pharmacists a new idea to reveal the potential molecular mechanism of surgical treatment for periodontitis, and provide valuable reference for follow-up treatment programs.
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PURPOSE: This study evaluated a novel magnetic compression technique (magnamosis) for creating a portacaval shunt in a canine model of portal hypertension, relative to traditional manual suture. METHODS: Portal hypertension was induced in 18 dogs by partial ligation of the portal vein (baseline). Six weeks later, extrahepatic portacaval shunt implantation was performed with either magnetic anastomosis rings, or traditional manual suture (n = 9, each). The two groups were compared for operative time, portal vein pressure, and serum biochemical indices. Twenty-four weeks post-implantation, the established anastomoses were evaluated by color Doppler imaging, venography, and gross and microscopic histological examinations. RESULTS: Anastomotic leakage did not occur in either group. The operative time to complete the anastomosis for magnamosis (4.12 ± 1.04 min) was significantly less than that needed for manual suture (24.47 ± 4.89 min, P < 0.01). The portal vein pressure in the magnamosis group was more stable than that in the manual suture group. The blood ammonia level at the end of the 24-week post-implantation observation period was significantly lower in the magnamosis group than in the manual suture group. Gross and microscopic histological examinations revealed that better smoothness and continuity of the vascular intima had been achieved via magnamosis than with manual suture. CONCLUSION: Magnamosis was superior to manual suture for the creation of a portacaval shunt in this canine model of portal hypertension.
Assuntos
Hipertensão Portal/cirurgia , Imãs , Derivação Portocava Cirúrgica/instrumentação , Anastomose Cirúrgica , Fístula Anastomótica/cirurgia , Animais , Modelos Animais de Doenças , Cães , Testes de Função Hepática , Fenômenos Magnéticos , Masculino , Duração da Cirurgia , Flebografia , Derivação Portocava Cirúrgica/métodos , Pressão na Veia Porta , Veia Porta/cirurgia , Técnicas de Sutura , Suturas , Ultrassonografia Doppler em CoresRESUMO
Phytolacca acinosa Roxb. (P. acinosa) is a recently discovered manganese hyperaccumulator plant from southern China. It is a good candidate for phytoremediation of manganese(Mn) polluted soil for its high biomass and fast growth. Knowledge of the tissue localization and identification of heavy metals can provide essential information on metal toxicity and bioaccumulation mechanisms. Synchrotron radiation X-ray fluorescence spectroscopy (SRXRF) microprobe was used in this study to investigate the cellular distributions of Mn and other elements in root, stem, leaf, petiole and midrib of P. acinosa. The highest Mn content was found in the vascular tissues of root, stem, petiole and midrib. Cortex in root played a key role in Mn absorption and Mn was limited in the vascular bundle during the process of transportation in stem. Moreover, Mn content in leaf epidermis was higher than that in mesophyll, which suggested that the sequestration of Mn in leaf epidermis might be one of the detoxification mechanisms of P. acinosa. The significance of other elemental (such as P, S, K, Ca, Fe, Zn and Cu) distribution patterns and the correlation with Mn were also discussed.
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Biodegradação Ambiental , Manganês/análise , Phytolacca/química , Espectrometria por Raios X/métodos , Oligoelementos/análise , Phytolacca/metabolismo , Poluentes do Solo/análiseRESUMO
China has one of the largest numbers of cancer patients. The huge expenses of medical care for cancer patients has brought heavy economic burden to the family. This paper briefly introduces the tumor medical insurance situation in China from the construction and composition of China's medical security system, the access of cancer patients to get health insurance, the challenges and developmental trend of China's medical security system, and two case studies that highlight different financial situations.
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The anaerobic ammonium oxidation (anammox) process, which can simultaneously remove ammonium and nitrite, both toxic to aquatic animals, can be very important to the aquaculture industry. Here, the presence and activity of anammox bacteria in the sediments of four different freshwater aquaculture ponds were investigated by using Illumina-based 16S rRNA gene sequencing, quantitative PCR assays and (15)N stable isotope measurements. Different genera of anammox bacteria were detected in the examined pond sediments, including Candidatus Brocadia, Candidatus Kuenenia and Candidatus Anammoxoglobus, with Candidatus Brocadia being the dominant anammox genus. Quantitative PCR of hydrazine synthase genes showed that the abundance of anammox bacteria ranged from 5.6 × 10(4) to 2.1 × 10(5) copies g(-1) sediment in the examined ponds. The potential anammox rates ranged between 3.7 and 19.4 nmol N2 g(-1) sediment day(-1), and the potential denitrification rates varied from 107.1 to 300.3 nmol N2 g(-1) sediment day(-1). The anammox process contributed 1.2-15.3% to sediment dinitrogen gas production, while the remainder would be due to denitrification. It is estimated that a total loss of 2.1-10.9 g N m(-2) per year could be attributed to the anammox process in the examined ponds, suggesting that this process could contribute to nitrogen removal in freshwater aquaculture ponds.
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Compostos de Amônio/metabolismo , Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Lagoas/microbiologia , Anaerobiose , Aquicultura , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Desnitrificação , Nitritos/metabolismo , Nitrogênio/metabolismo , Oxirredução , RNA Ribossômico 16S/genéticaRESUMO
To explore the ionic mechanisms of memory deficits induced by cholinergic lesion, whole-cell patch clamp recording techniques in combination with single-cell RT-PCR were used to characterize delayed rectifier potassium currents (IK) in acutely isolated hippocampal pyramidal neurons of scopolamine-induced cognitive impairment rats. Scopolamine could induce deficits in spatial memory of rats. The peak amplitude and current density of IK measured in hippocampal pyramidal neurons were increased from 1.2+/-0.6 nA and 38+/-19 pA/pF of the control group (n=12) to 1.8+/-0.5 nA and 62+/-24 pA/pF (n=48, P<0.01) of the scopolamine-treated group. The steady-state activation curve of IK was shifted about 8 mV (P<0.01) in the direction of hyperpolarization in scopolamine-treated rats. The mRNA level of Kv2.1 was increased (P<0.01) in the scopolamine-treated group, but there was no significant change of Kv1.5 mRNA level. The present study demonstrated for the first time that IK was enhanced significantly in hippocampal pyramidal neurons of scopolamine-induced cognitive impairment rats. The increase of Kv2.1 mRNA expression in hippocampal pyramidal cells might be responsible for the enhancement of IK and could be the ionic basis of the memory deficits induced by scopolamine.
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Potenciais de Ação/fisiologia , Memória/fisiologia , Antagonistas Muscarínicos/farmacologia , Neurônios/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Escopolamina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Canal de Potássio Kv1.5 , Masculino , Memória/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Potássio/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Canais de Potássio ShabRESUMO
Phytolacca americana L. (P. americana) is a manganese (Mn) hyperaccumulator and cell wall plays an important role in the accumulation and detoxicity of Mn. We studied the impact of pH and Mn initial concentration on the binding of Mn by the leaf cell wall of P. americana, and explored the binding mechanisms by Fourier Transform Infrared Spectroscopy (FTIR) and synchrotron-based X-ray Absorption Fine Structure (XAFS) Spectroscopy. The results show that the optimum pH of Mn bingding for the leaf cell wall is between 5 and 6. The adsorption behavior of leaf cell wall can be described by Langmuir equation (R2 = 0.978 5) and the maximum adsorption of Mn on the leaf cell wall is 62.50 µmol x g(-1). Hydronyl and carbonyl groups are involved in the binding of Mn on the leaf cell wall. The Mn absorbed on the leaf cell wall is bonded by 6.3 oxygen around, and the bond length of Mn-O is 0.216 nm, which indicates the binding mechasnism of Mn to cell wall was inner-sphere complexation.
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Parede Celular/química , Manganês/química , Phytolacca americana/citologia , Folhas de Planta/citologia , Biodegradação Ambiental , Poluentes do Solo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia por Absorção de Raios XRESUMO
Galantamine is an acetylcholinesterase inhibitor in Alzheimer's disease therapy. In the present study, we investigated the effects of galantamine on delayed rectifier potassium current (I(K(DR))) and transient outward potassium current (I(K(A))) in acutely dissociated rat hippocampal pyramidal neurons by using whole-cell patch clamp technique. I(K(DR)) was inhibited by galantamine in a concentration-dependent manner, while I(K(A)) remained unaffected. The IC(50) value for the blocking action of galantamine on I(K(DR)) was calculated as 2.0 microM. At the concentration of 10 microM, galantamine inhibited I(K(DR)) by 40.2% at +40 mV when depolarized from -50 mV, and shifted the activation curve and inactivation curve of I(K(DR)) to negative potential by -3.8 mV and -11.0 mV, respectively. In conclusion, galantamine potently inhibits I(K(DR)) but not I(K(A)) in rat hippocampal pyramidal neurons.
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Galantamina/farmacologia , Hipocampo/efeitos dos fármacos , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização/fisiologia , Células Piramidais/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Inibidores da Colinesterase/farmacologia , Eletrofisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/efeitos dos fármacos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Células Piramidais/fisiologia , Ratos , Ratos WistarRESUMO
Potassium channel dysfunction has been indicated in Alzheimer's disease. In the present study, spatial memory, the activity of cortical acetylcholinesterase (AChE) and the expressions of inward rectifier potassium channels (Kir) were measured after ibotenic acid lesions of nucleus basalis magnocellularis (nbm) in rats. Expressions of Kir (Kir2.1, Kir3.1, Kir6.1 and Kir6.2) at mRNA level were assessed using reverse transcription-polymerase chain reaction. At 28 days after ibotenic acid injection, the spatial memory of rats was significantly impaired accompanied by a 32% reduction of cortical AChE activity. Furthermore, the expression of Kir6.2 was increased by 79.3% in cortex, and that of Kir6.1 was increased by 172.1% in hippocampus, while no obvious changes in the mRNA expression of Kir2.1 and Kir3.1 were detected. This study indicated that the expression of adenosine triphosphate-sensitive potassium channel was area and channel subtype specifically increased following nbm lesions.
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Acetilcolina/deficiência , Doença de Alzheimer/metabolismo , Núcleo Basal de Meynert/fisiopatologia , Córtex Cerebral/metabolismo , Fibras Colinérgicas/patologia , Canais de Potássio Corretores do Fluxo de Internalização/genética , RNA Mensageiro/metabolismo , Acetilcolinesterase/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Animais , Núcleo Basal de Meynert/efeitos dos fármacos , Núcleo Basal de Meynert/lesões , Córtex Cerebral/fisiopatologia , Fibras Colinérgicas/efeitos dos fármacos , Agonistas de Aminoácidos Excitatórios/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G , Ácido Ibotênico/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Canais de Potássio/genética , Ratos , Ratos WistarRESUMO
AIM: To discover new regulators of potassium channel, an in vitro assay based on DiBAC4 (3) to determine the fluorescence was established for high throughput screening. METHODS: A cell-based 96-well format fluorescence assay using DiBAC4 (3) in cultured PC12 cells was described. Cells were loaded with 5 mumol.L-1 DiBAC4 (3) and incubated at 37 degrees C for 30 min before adding KCl or several known potassium channel regulators. The cellular DiBAC4 (3) fluorescence responce was then detected. The fluorescence changes can be used to evaluate membrane potential changes, which are determined mainly by potassium channels. RESULTS: Extracellular high K(+)-induced depolarization and several potassium channel blockers including 4-AP, TEA, E-4031, glibenclamide, quinidine and nifedipine all evoked increases in DiBAC4 (3) fluorescence response. The potassium channel opener, cromakalim, evoked decrease in DiBAC4 (3) fluorescence response. The fluorescence changes of 4-AP, TEA, glibenclamide, nifedipine and cromakalim were in a concentration-dependent manner. In 76 compounds screened by using the established DiBAC4 (3)-based assay, 9 compounds were found to change the fluorescence dose-dependently. Patch clamp technique is needed to further testify and screen their actions on potassium currents. CONCLUSION: The DiBAC4 (3)-based assay is easily operated, economical and repeatable. So, it can be performed by high throughput screening for potassium channel regulators.
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Barbitúricos/química , Isoxazóis/química , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/efeitos dos fármacos , 4-Aminopiridina/farmacologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Cromakalim/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Nifedipino/farmacologia , Células PC12 , Técnicas de Patch-Clamp , Piperidinas/farmacologia , Piridinas/farmacologia , Quinidina/farmacologia , RatosRESUMO
AIM: To study mRNA expression alteration of two-pore potassium channels in the brain of beta-amyloid peptide25-35 (beta-AP25-35)-induced memory impaired rats. METHODS: Memory impairments induced in rats by single icv injection of beta-AP25-35 (2 mmol.L-1) 5 microL were assessed in the Morris water maze test. The mRNA expression levels of three two-pore potassium channels TREK-1, TREK-2 and TRAAK were detected in rat cerebral cortex and hippocampus by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In the Morris water maze test, the escape latencies of the beta-AP25-35-treated rats were longer than those of the control group in 1st, 2nd and 4th training day, suggesting that the memory of beta-AP25-35-treated rats was obviously impaired. Compared with the control group, the mRNA levels of TREK-1, TREK-2 and TRAAK in the hippocampus of the beta-AP25-35-treated rats were increased by 40.0%, 27.9% and 18.9%, respectively; while no significant change of TREK-1, TREK-2 and TRAAK mRNA levels was observed in the cortex. CONCLUSION: The mRNA expression levels of two-pore potassium channels were increased significantly in the brain of beta-AP25-35-induced memory impaired rats.
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Córtex Cerebral/metabolismo , Hipocampo/metabolismo , Transtornos da Memória/metabolismo , Canais de Potássio de Domínios Poros em Tandem , Canais de Potássio/biossíntese , Peptídeos beta-Amiloides , Animais , Masculino , Aprendizagem em Labirinto , Transtornos da Memória/induzido quimicamente , Fragmentos de Peptídeos , Canais de Potássio/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
AIM: To study mRNA expression difference of voltage-dependent potassium channels in the brain of scopolamine-induced memory impaired rats. METHODS: Memory impairments induced in rats by scopolamine (1 mg.kg-1) were assessed in the Morris water maze test. After rats were injected intraperitoneally with scopolamine for 6 days, the mRNA expression level of five voltage-dependent potassium channels, Kv1.4, Kv1.5, Kv2.1, Kv4.2 and Kv4.3 were detected in the rat cortex and hippocampus by RT-PCR. RESULTS: Scopolamine (1 mg.kg-1) was shown to significantly induce memory impairment in rats. The mRNA levels of Kv4.2 were decreased by 28.8% and 33.9% in the cortex and hippocampus, respectively. The mRNA levels of Kv1.4 and Kv2.1 were increased in the hippocampus by 111.7% and 64.3%, respectively. There were no differences in the brain mRNA levels of other voltage-dependent potassium channels in scopolamine-induced memory impaired rat. CONCLUSION: The mRNA expression levels of voltage-dependent potassium channels changed significantly in the brain of scopolamine-induced memory impaired rats.
Assuntos
Córtex Cerebral/metabolismo , Hipocampo/metabolismo , Transtornos da Memória/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/biossíntese , Escopolamina , Adjuvantes Anestésicos , Animais , Córtex Cerebral/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Transtornos da Memória/induzido quimicamente , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , RNA Mensageiro/biossíntese , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
A pot experiment was conducted to study the effects of UV-B radiation enhancement alone, 1,2,4-trichlorobenzene (TCB) contamination soil alone, and the combined stress on the growing process, stomatal resistance and leaf structure of green vegetable. The results showed that 1,2,4-TCB contamination alone had more significant inhibitory effect on the growth of green vegetable than the combined stress. Both UV-B radiation enhancement and 1,2,4-TCB contamination reduced the stomatal resistance of front and reverse leaves. Enhanced UV-B radiation resulted in the albino of leaves. 1,2,4-TCB contamination resulted in the fading of leaf color and the appearing of black spots on leaf surfaces, and the enhanced UV-B radiation strengthened the black-spot symptom. In conclusion, the effects of UV-B radiation enhancement alone, 1,2,4-trichlorobenzene (TCB) contamination soil alone and the combined stress on the growth indicators of green vegetable were different.