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1.
Pers Ubiquitous Comput ; : 1-8, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34393693

RESUMO

Most movie recommendation methods use hard-clustering and simple collaborative filtering techniques in order to achieve their end results. However, these methods tend to overlook crucial aspects of both users and items. When these methods hard cluster a movie item into a cluster, they turn a blind eye to the fact that the item also exhibits some properties of another cluster's items. Recommender systems facilitate users and relevant things expeditiously supported their requests and historic communications with alternative customers. Recommendation systems are a crucial portion of signifying things particularly in streaming amenities. For streaming motion-picture show services like Netflix, recommendation methods are vital for serving to users notice fresh movies to get pleasure from. However, massive amounts of information will turn out restrictions in recommendations due to accuracy as a result of diversity and meagerness problems. Our work proposes a unique hybrid technique that mixes collaborative filtering and characteristics of demographic filtering technique to point the close users, and associate against one another. This technique has been established over associate in tending analysis of the way to cut back the blunders in grading estimates supported users' earlier communications that ends up in improved prediction accuracy in among completely different algorithms. Additionally, a feature combination technique is utilized that progresses the expectation accuracy and to check our method, using MovieLens 1M dataset, we contended an offline assessment, already available assessment tactics, and compared the same with the output factors to support authenticating the proposed procedure.

2.
Andrologia ; 47(5): 568-78, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24909458

RESUMO

The study was conducted to evaluate the vanadium-induced testicular toxicity and its effect on sperm parameters, sperm nuclear DNA damage and histological alterations in Sprague Dawley rats and to assess the protective effect of G-hesperidin against this damage. Treatment of rats with vanadium at a dose of 1 mg kg bw(-1) for 90 days resulted in significant reduction in serum testosterone levels, sperm count and motility. Further, a parallel increase in abnormal sperm morphology and adverse histopathological changes in testis was also associated with vanadium administration when compared to normal control. Moreover, sperm chromatin dispersion assay revealed that vanadium induces sperm nuclear DNA fragmentation. A marked increase in testicular malondialdehyde levels and decreased activity of antioxidant enzymes such as superoxide dismutase and catalase indicates vanadium-induced oxidative stress. Co-administration of G-hesperidin at a dose of 25 and 50 mg kg bw(-1) significantly attenuated the sperm parameters and histological changes by restoring the antioxidant levels in rat testis. These results suggested that vanadium exposure caused reduced bioavailability of androgens to the tissue and increased free radical formation, thereby causing structural and functional changes in spermatozoa. G-hesperidin exhibited antioxidant effect by protecting the rat testis against vanadium-induced oxidative damage, further ensures antioxidant potential of bioflavonoids.


Assuntos
Dano ao DNA/efeitos dos fármacos , Glucosídeos/farmacologia , Hesperidina/análogos & derivados , Espermatozoides/efeitos dos fármacos , Doenças Testiculares/induzido quimicamente , Testículo/efeitos dos fármacos , Oligoelementos/toxicidade , Vanádio/toxicidade , Animais , Catalase/efeitos dos fármacos , Catalase/metabolismo , Hesperidina/farmacologia , Infertilidade Masculina/induzido quimicamente , Masculino , Malondialdeído/metabolismo , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Motilidade dos Espermatozoides/efeitos dos fármacos , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Testículo/patologia
3.
Cell Mol Life Sci ; 69(7): 1179-91, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22068610

RESUMO

During development, axonal projections have a remarkable ability to innervate correct dendritic subcompartments of their target neurons and to form regular neuronal circuits. Altered axonal targeting with formation of synapses on inappropriate neurons may result in neurodevelopmental sequelae, leading to psychiatric disorders. Here we show that altering the expression level of the polysialic acid moiety, which is a developmentally regulated, posttranslational modification of the neural cell adhesion molecule NCAM, critically affects correct circuit formation. Using a chemically modified sialic acid precursor (N-propyl-D: -mannosamine), we inhibited the polysialyltransferase ST8SiaII, the principal enzyme involved in polysialylation during development, at selected developmental time-points. This treatment altered NCAM polysialylation while NCAM expression was not affected. Altered polysialylation resulted in an aberrant mossy fiber projection that formed glutamatergic terminals on pyramidal neurons of the CA1 region in organotypic slice cultures and in vivo. Electrophysiological recordings revealed that the ectopic terminals on CA1 pyramids were functional and displayed characteristics of mossy fiber synapses. Moreover, ultrastructural examination indicated a "mossy fiber synapse"-like morphology. We thus conclude that homeostatic regulation of the amount of synthesized polysialic acid at specific developmental stages is essential for correct synaptic targeting and circuit formation during hippocampal development.


Assuntos
Homeostase , Moléculas de Adesão de Célula Nervosa/metabolismo , Ácidos Siálicos/metabolismo , Sinapses/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL
4.
Anesth Essays Res ; 16(1): 1-6, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36249135

RESUMO

Background: Choosing the correct Endotracheal tube (ETT) size is important in paediatric patients because an inappropriately large and small sized tube has its own disadvantages and chances of re-intubation with different size tube is high. The currently available modalities do not reflect the actual tracheal diameter for selection of endotracheal tube. Ultrasonography (USG) guided evaluation of transverse diameter at subglottic region may be helpful to estimate the proper size of ETT. We tested the hypothesis that Ultrasound guided subglottic diameter better predicts optimal ETT size than existing methods. Aims: To predict the appropriate size of ETT in pediatric patients to avoid multiple attempts of intubation and airway edema using simple noninvasive USG-guided methods. Settings and Design: Design: Prospective study. Settings: Tertiary care hospital. Materials and Methods: Institutional ethical committee clearance no. BMCRI/PS/138/2020-21 was taken. Laryngoscopy and endotracheal intubation were done in 27 pediatric patients of age 2-15 years using a predetermined-sized ETT, estimated by ultrasonography. ETT size was considered optimal when the cuff leak test was negative. If there was resistance to ETT passage into the trachea, the tube was exchanged with one that was 0.5 mm smaller. If the cuff leak test was positive, then the ETT was exchanged for one with the 0.5-mm larger tube. The comparison was done between the size of ETT calculated by USG-guided subglottic diameter, age, height-related formulas, and clinical methods to look for accuracy of prediction for proper ETT size after cuff leak test. Statistical Analysis: The data collected were entered into Microsoft Excel and analyzed using SPSS version 22. IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp. Appropriate parametric and nonparametric tests were applied wherever necessary. Categorical data: Represented in the form of frequencies and proportions. Continuous data: Represented as mean and standard deviation. Paired sample test: Test to identify the mean difference between two quantitative variables. Kappa statistics: To measure the level of agreement. Results: A total of 27 children of age between 2 and 15 years were selected, out of which 15 were male and 12 were female. The accuracy of predicting appropriate ETT size is greater in ultrasound-guided subglottic diameter when compared to conventional clinical assessment and age- and height-related formula and almost the same accuracy as the clinical method. Conclusion: Ultrasound-guided subglottic diameter is an easy, effective, and noninvasive way of predicting accurate ETT size in the pediatric population.

5.
J Ayurveda Integr Med ; 12(3): 529-534, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34376353

RESUMO

BACKGROUND: Andrographis paniculata (Burm.f.) Nees has been well-researched for its immunomodulatory effects. OBJECTIVE(S): To investigate the immunomodulatory effects of standardized A. paniculata extract (SAPE) in healthy adults. MATERIALS AND METHODS: The study was an open-label, single-centre study conducted for 30 days. Thirty participants with absolute lymphocyte counts of 1000-4000 cells/mm3 were enrolled and were instructed to ingest 200 mg of SAPE daily for 30 days. The participants visited the clinic at baseline, and days 3, 7, and 30. Immune cells such as NK cell (CD3-CD16+CD56+), T cells (CD3+), T helper cells (CD3+CD4+), T cytotoxic cells (CD3+CD8+) were measured using flow cytometry. Serum cytokines that include interferon gamma (IFN-γ), interleukin-4 (IL-4), interleukin-2 (IL-2), interleukin-12 (IL-12), and tumor necrosis factor alpha (TNF-α) were measured using ELISA. The SAPE used in this study was a standardized proprietary extract (AP-Bio®/KalmCold®) developed from the leaf extracts of A. paniculata. RESULTS: SAPE increased T cells, T helper cells and significantly increased IFN-γ, IL-4, and decreased IL-2 at day 30. A subgroup analysis of participants with absolute lymphocyte counts of 1000-3000 cells/mm3 indicated that there is a significant increase in the T cells, T helper cells at day 7 and 30 and significant increase in IFN-γ, IL-4 and decrease in IL-2 at day 30. There was no treatment related adverse effects following SAPE intake for 30 days. CONCLUSION: Supplementation of SAPE resulted in immunomodulatory effects evidenced by its effects on immune cells and cytokines and it was found to be safe and tolerable.

6.
Ann Neurol ; 66(3): 310-22, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19798635

RESUMO

OBJECTIVE: Multiple sclerosis (MS) is considered a chronic inflammatory and demyelinating disease of the central nervous system. Evidence that axonal and neuronal pathology contributes to the disease is accumulating, however, the distribution of neuronal injury as well as the underlying mechanisms have not yet been fully clarified. Here, we investigated the role of neuronal cell loss in MS and its animal model, experimental autoimmune encephalomyelitis (EAE). METHODS: We performed electrophysiological investigations in MS patients, including assessment of compound muscle action potentials and motor unit numbers and quantified neuronal cell loss in human MS samples and different EAE models by high-precision stereology. RESULTS: Both electrophysiological and morphological analyses indicated a massive loss of lower motor neurons in MS patients. We regularly found dying spinal motor neurons surrounded by CD3+ (CD4+ as well as CD8+) T cells expressing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). We observed a similar degree of damage and immune attack in different variants of EAE; the lower motor neurons were preserved in adoptive transfer EAE induced with TRAIL-deficient T lymphocytes. INTERPRETATION: Our study indicates that damage to lower motor neurons and TRAIL-mediated inflammatory neurodegeneration in the spinal cord contribute to MS pathology.


Assuntos
Encefalomielite Autoimune Experimental/patologia , Neurônios Motores/patologia , Esclerose Múltipla/patologia , Transferência Adotiva , Adulto , Animais , Apoptose/imunologia , Contagem de Células , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Feminino , Humanos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Degeneração Neural/imunologia , Degeneração Neural/patologia , Neurônios/imunologia , Neurônios/patologia , Medula Espinal/imunologia , Medula Espinal/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Ligante Indutor de Apoptose Relacionado a TNF/imunologia
7.
J Family Med Prim Care ; 9(3): 1656-1661, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32509667

RESUMO

BACKGROUND: Gingival recession (GR) is a common clinical feature of periodontal disease and is an undesirable condition. More than 50% of the population has one or more sites with GR ≥ 1 mm. MATERIAL AND METHODS: In this study 15 subjects were subjected to initial periodontal therapy such as ultrasonic scaling and root planning with hand instruments and curettes. Patient is motivated for home care. The buccal fat pad is harvested and sutured in the gingival recession area and followed up for 6 months and root coverage was calculated. RESULTS: At baseline mean recession of 5.60 ± 1.18 mm, probing depth of 0.73 ± 0.59 mm, clinical attachment loss of 6.40 ± 1.18 mm were recorded. At the end of 6 months, the mean recession was reduced from 5.60 ± 1.18 mm to 2.87 ± 0.74 mm, probing depth was increased from 0.73 ± 0.59 mm to 1.73 ± 0.70 mm and clinical attachment loss was decreased from 6.40 ± 1.18 mm to 4.53 ± 0.83 mm.The difference between baseline score and six months score for all three parameters are statistically significant. CONCLUSION: Buccal fat pad is a predictable procedure to cover Miller's class III and class IV gingival recession defects. There was a definitive improvement in clinical parameters (reduction in gingival recession, increased probing depth, gain in clinical attachment) after 6 months. There was 46.78% improvement in root coverage which was statistically significant.

8.
Indian J Pharmacol ; 52(4): 260-265, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33078726

RESUMO

INTRODUCTION: Medication errors (MEs) can prolong hospital stay and are a cause of morbidity and mortality. Studies evaluating MEs and its determinants in Indian neonatal intensive care units (NICUs) are limited. Therefore, this study was done to assess the prevalence, characteristics, determinants, and outcomes of MEs in an Indian NICU setting. METHODOLOGY: A prospective observational study was conducted over a 1-year period (January-December 2016) among neonates receiving medications in NICU. Systematic random sampling was done, and data were collected using a semi-structured questionnaire after obtaining informed consent from the mother. An ME self-reporting system was also established. Data were analyzed using Chi-squared test and Student's t-test. Binary logistic regression was used to analyze the determinants of MEs. RESULTS: Among 269 babies included in the study, 57% (n = 154) were male babies with mean (standard deviation [SD]) birth weight of 2.59 kg (0.701). About 79% (n = 213/269) of the neonates were appropriate for gestational age. The mean (SD) duration of stay in NICU was 7.58 (5.07) days, and 67% of the babies had polypharmacy (use of ≥5 medications). The prevalence of MEs was 22% (95% confidence interval [CI]: 16.96%, 26.84%, n = 108) of all babies, of which only 2% (n = 2) were life threatening. Seventy-seven percent (n = 83) of these errors occurred during administration/preparation and 18% (n = 19) while prescribing. The significant determinants of MEs (adjusted odds ratio [95% CI]) include polypharmacy (4.126 [1.917-8.880]), duration of stay >7 days (1.335 [1.198-1.488]), and babies referred from outside (2.592 [1.217-5.521]). CONCLUSIONS: MEs were common in NICU setting. The occurrence of life-threatening MEs was minimal. Longer duration of hospital stay, polypharmacy, and babies born outside were significantly associated with occurrence of MEs.


Assuntos
Unidades de Terapia Intensiva Neonatal , Erros de Medicação/estatística & dados numéricos , Feminino , Humanos , Índia , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Centros de Atenção Terciária
9.
Anesth Essays Res ; 13(1): 169-173, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31031500

RESUMO

BACKGROUND: Intraperitoneal local anesthetic is an effective analgesic approach following laparoscopic cholecystectomy. AIMS: The aim of the present study was to compare the antinociceptive effects of intraperitoneal ropivacaine plus fentanyl with ropivacaine plus dexmedetomidine in patients undergoing laparoscopic cholecystectomy. SETTINGS AND DESIGNS: This was randomized, prospective, double-blinded, observational clinical study. METHODS: A total of 80 patients, undergoing elective laparoscopic cholecystectomy under general anesthesia were randomly assigned to one of the two equal groups to receive either of the following: Group RF (n = 40) were given 30 mL of 0.2% ropivacaine combined with 1 µg/kg fentanyl (diluted in 2 mL normal saline) and Group RD (n = 40) were given 30 mL of 0.2% ropivacaine combined with 1 µg/kg dexmedetomidine (diluted in 2 mL normal saline) through trocars. The quality of analgesia was assessed using visual analog scale score (VAS). Time to the first request of analgesia, the total dose of analgesic in the first 24 h and adverse effects were noted. STATISTICAL ANALYSIS: The data were analyzed with the Students' t-test and Chi-square test. RESULTS: VAS score at different time intervals, overall VAS in 24 h was significantly lower (1.68 ± 0.46 vs. 4.47 ± 0.94), time to first request of analgesia (min) was longest (122.7 ± 24.5 vs. 89.3 ± 13.2) and total analgesic consumption (mg) was lowest (95.3 ± 15.6 vs. 135.7 ± 75.1) in RD group than in RF group. CONCLUSION: The antinociceptive effect of the intraperitoneal instillation of ropivacaine in combination with dexmedetomidine is superior to ropivacaine combined with fentanyl.

10.
Anesth Essays Res ; 13(1): 174-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31031501

RESUMO

BACKGROUND: The ideal dose of butorphanol for brachial plexus block is not well known. AIMS: This study was carried out to evaluate 1 mg and 2 mg of butorphanol added to 0.375% levobupivacaine, with regard to the duration of analgesia. Our study also sought to assess the onset and duration of sensorimotor blockade, hemodynamic effects, sedation, and adverse effects. SETTINGS AND DESIGN: This study was a prospective, randomized, double-blinded, and comparative study. METHODS: Eighty adult patients of either sex undergoing upper limb surgeries under supraclavicular brachial plexus block were randomly allocated into two groups. Group LB1 received 29 ml of 0.375% levobupivacaine plus 1 mg of butorphanol diluted in 1 ml of normal saline. Group LB2 received 29 ml of 0.375% levobupivacaine plus 2 mg of butorphanol diluted in 1 ml of normal saline. The onset and duration of sensorimotor blockade, level of sedation, duration of analgesia, and adverse effects were assessed. STATISTICAL ANALYSIS: The data were analyzed with Student's t-test and Chi-square test. RESULTS: The onset of sensory (P = 0.032) and motor block (P = 0.026) was earlier in Group LB2 than in Group LB1. The duration of analgesia was significantly prolonged in Group LB2 (643.55 ± 131.6 vs. 511.73 ± 128.6 min; P = 0.001). The incidence of sedation was observed in more number of patients in Group LB2 (P = 0.01). Furthermore, the incidence of nausea, vomiting, and pruritus were observed in more number of patients in Group LB2 (P < 0.05). CONCLUSION: Higher dose of butorphanol in brachial plexus block hastens the onset and prolongs the duration of sensorimotor blockade and analgesia but is associated with a higher incidence of sedation which requires intense monitoring.

11.
Trop Doct ; 38(2): 89-91, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18453495

RESUMO

Between January 2005 and December 2006, a higher incidence of paratyphoid fever (53.8%) compared to typhoid fever (44.9%) has been observed at a tertiary hospital in South India. A definite seasonal pattern of incidence is seen in paratyphoid fever (peak incidence during October-December, i.e., post monsoon period) but not in typhoid fever. Decreased fluoroquinolone susceptibility is much higher in S. Paratyphi A (98.8%) as compared to S. Typhi (46.5%). These findings are of importance in therapeutic decision making, development of vaccination strategies and implementing public health measures for disease control.


Assuntos
Antibacterianos/farmacologia , Salmonella paratyphi A/efeitos dos fármacos , Salmonella typhi/efeitos dos fármacos , Estações do Ano , Febre Tifoide/epidemiologia , Adolescente , Adulto , Idoso , Sangue/microbiologia , Criança , Pré-Escolar , Meios de Cultura , Feminino , Humanos , Incidência , Índia/epidemiologia , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Salmonella paratyphi A/classificação , Salmonella paratyphi A/isolamento & purificação , Salmonella typhi/classificação , Salmonella typhi/isolamento & purificação , Febre Tifoide/microbiologia
13.
Data Brief ; 6: 15-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26759823

RESUMO

This data article contains the data related to the research article "Characterization, biorecognitive activity and stability of WGA grafted lipid nanostructures for the controlled delivery of rifampicin" (Pooja et al. 2015) [1]. In the present study, SLN were prepared by a single emulsification-solvent evaporation method and the various steps of SLN preparation are shown in a flow chart. The preparation of SLN was optimized for various formulation variables including type and quantity of lipid, surfactant, amount of co-surfactant and volume of organic phase. Similarly, effect of variables related to homogezation, sonication and stirring processes, on the size and surface potential of SLN was determined and optimized.

15.
Indian J Pediatr ; 82(5): 433-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25278280

RESUMO

OBJECTIVES: To identify biomarkers for neuronal injury and outcome in perinatal asphyxia. METHODS: This prospective cohort study was done in authors' level III NICU involving 80 neonates - 40 babies with perinatal asphyxia and 40 weight and gender matched normal neonates. Levels of cytokines IL-6, IL -1ß, IL-2 and TNF -α in cord blood of these neonates were estimated and correlated with the severity of asphyxia and developmental outcome at 6 mo using Baroda Developmental Score. RESULTS: The baseline parameters revealed that there was no statistically significant difference between the two groups in terms of maternal age, parity, gestational age, gender and birth weight. The levels of cytokines IL-6 (p < 0.001) and IL-1beta (p < 0.03) were significantly higher in babies with perinatal asphyxia and correlated with the severity of asphyxia. The levels of IL-6 and IL-1ß had significant negative correlation with developmental score at 6 mo. A cut off level of 14.18 pg/ml for IL-6 had 92.3 % sensitivity and 57.7 % specificity [Area under the curve = 0.80 (0.62-0.84)] for adverse neuro-developmental outcome while it was 11.17 pg/ml for IL-1ß with a sensitivity of 69.2 % and specificity of 71.2 % [Area under the curve = 0.67 (0.57-0.80)]. CONCLUSIONS: IL-6 and IL-1 ß are good predictive markers of severity of asphyxia and adverse neurological outcome.


Assuntos
Asfixia Neonatal/sangue , Biomarcadores/sangue , Mediadores da Inflamação/sangue , Adulto , Estudos de Coortes , Citocinas/sangue , Feminino , Sangue Fetal , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Gravidez , Estudos Prospectivos , Sensibilidade e Especificidade
16.
Chem Phys Lipids ; 193: 11-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26409629

RESUMO

Targeted nanomedicines improve the delivery of drugs by increasing the drug concentration at target site, protecting the premature degradation and releasing the encapsulated drug in controlled manner. To make rifampicin (RFN) delivery more effective, we designed and characterized wheat germ agglutinin (WGA) conjugated, RFN loaded solid-lipid nanoparticles (WRSN). Nanoparticles were prepared by solvent emulsification/evaporation and conjugated with fluorescein isothiocyanate-labeled WGA. Important characteristics, such as particle size, zeta potential, encapsulation efficiency, conjugation efficiency and in vitro drug release behavior, were investigated. WGA conjugation to the nanoparticles was confirmed by Fourier Transform Infrared (FTIR) analysis. Conjugation efficiency was determined by fluorescent spectroscopy and Bradford assay. RFN was released from nanoparticles via the diffusion-controlled, non-fickian and supercase II mechanism. A haemaglutination test confirmed that WGA retained its bio-recognition activity and sugar-binding specificity after it was coupled with the nanoparticles. In vitro experiments demonstrated that WRSN interacted more than non-conjugated nanoparticles with porcine mucin. WRSN were stable in the presence of electrolytes up to 1M concentration. Therefore, WGA-conjugated solid lipid nanoparticles could be a promising tool for the controlled delivery of RFN or other anti-tubercular drugs.


Assuntos
Antibióticos Antituberculose/administração & dosagem , Preparações de Ação Retardada/química , Lipídeos/química , Nanopartículas/química , Rifampina/administração & dosagem , Aglutininas do Germe de Trigo/química , Animais , Preparações de Ação Retardada/metabolismo , Liberação Controlada de Fármacos , Metabolismo dos Lipídeos , Mucinas/metabolismo , Nanopartículas/metabolismo , Tamanho da Partícula , Suínos , Aglutininas do Germe de Trigo/metabolismo
17.
Chem Commun (Camb) ; (18): 1736-7, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-12240290

RESUMO

A green process, using a recyclable tungstate-exchanged Mg-Al layered double hydroxide (LDH-WO4(2-)) heterogenised catalyst and aqueous H2O2 oxidant in water, leads to N-oxidation of aliphatic tert-amines to amine N-oxides in quantitative yields, at a high rate at room temperature.

18.
Physiol Behav ; 51(4): 851-6, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1594685

RESUMO

Bilateral lesions of accumbens and caudate nuclei resulted in significant and sustained increase in water intake. Administration of different doses of dopamine (DA) into these nuclei facilitated a dose-dependent increase in 24-h water intake, whereas injection of spiperone following administration of DA inhibited DA-facilitated water intake in a dose-dependent manner. Conversely, administration of DA and spiperone did not elicit any change in water intake in septal nuclei; rather septal lesion facilitated the water intake. This suggests that the nucleus accumbens and nucleus caudatus act as facilitatory thirst areas and that DA is a possible dipsogenic neurotransmitter in these nuclei. This also suggests that the nucleus septal lateralis is a thirst-inhibiting centre where DA may not be involved in dipsogenesis.


Assuntos
Núcleo Caudado/fisiologia , Dopamina/fisiologia , Ingestão de Líquidos/fisiologia , Núcleo Accumbens/fisiologia , Receptores Dopaminérgicos/fisiologia , Animais , Mapeamento Encefálico , Dominância Cerebral/fisiologia , Feminino , Vias Neurais/fisiologia , Ratos
19.
Biol Trace Elem Res ; 158(2): 203-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24599700

RESUMO

Selenium exerts many, if not most, of its physiological functions as a selenocysteine moiety in proteins. Selenoproteins are involved in many biochemical processes including regulation of cellular redox state, calcium homeostasis, protein biosynthesis, and degradation. A neurodevelopmental syndrome called progressive cerebello-cortical atrophy (PCCA) is caused by mutations in the selenocysteine synthase gene, SEPSECS, demonstrating that selenoproteins are essential for human brain development. While we have shown that selenoproteins are required for correct hippocampal and cortical interneuron development, little is known about the functions of selenoproteins in the cerebellum. Therefore, we have abrogated neuronal selenoprotein biosynthesis by conditional deletion of the gene encoding selenocysteyl tRNA([Ser]Sec) (gene symbol Trsp). Enzymatic activity of cellular glutathione peroxidase and cytosolic thioredoxin reductase is reduced in cerebellar extracts from Trsp-mutant mice. These mice grow slowly and fail to gain postural control or to coordinate their movements. Histological analysis reveals marked cerebellar hypoplasia, associated with Purkinje cell death and decreased granule cell proliferation. Purkinje cell death occurs along parasagittal stripes as observed in other models of Purkinje cell loss. Neuron-specific inactivation of glutathione peroxidase 4 (Gpx4) used the same Cre driver phenocopies tRNA([Ser]Sec) mutants in several aspects: cerebellar hypoplasia, stripe-like Purkinje cell loss, and reduced granule cell proliferation. Parvalbumin-expressing GABAergic interneurons (stellate and/or basket cells) are virtually absent in tRNA([Ser]Sec)-mutant mice, while some remained in Gpx4-mutant mice. Our data show that selenoproteins are specifically required in postmitotic neurons of the developing cerebellum, thus providing a rational explanation for cerebellar hypoplasia as occurring in PCCA patients.


Assuntos
Cerebelo/anormalidades , Malformações do Sistema Nervoso/metabolismo , Neurônios/metabolismo , Selenoproteínas/biossíntese , Selenoproteínas/deficiência , Animais , Cerebelo/metabolismo , Deficiências do Desenvolvimento/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos
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