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1.
JPRAS Open ; 31: 137-140, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35198718

RESUMO

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering dermatological condition that can be triggered by several external factors. Here, we present a case of an immunocompetent patient with no prior dermatological history, who developed BP as a result of autologous skin graft surgery. It is an uncommon surgical complication and was most likely triggered by the trauma of the surgery itself. Our patient's bullae first developed a month after his surgery at both surgical sites and subsequently became widespread. The diagnosis was confirmed histologically using punch biopsies of a bulla and the perilesional skin for direct immunofluorescence together with indirect immunofluorescence of the serum for anti-skin antibodies. Initial topical treatment and regular wound care were not improving the patient's condition at a satisfactory rate. Therefore, the patient was started on systemic steroids, which unfortunately resulted in a presumed split skin graft infection requiring admission. After histological diagnosis confirmation was achieved, the Dermatology team formulated a treatment plan, which combined both topical and systemic medication. The patient is currently making a good recovery and the graft loss resulting from the condition is only partial, requiring no further surgery. We present this case as a reminder to all clinicians that, although rare, BP can be triggered by skin grafting, even in patients with no prior history of it or any predisposing conditions. This autoimmune condition needs to be recognised and treated promptly to ensure optimal clinical outcomes and minimise graft loss.

2.
Psychol Med ; 47(10): 1771-1783, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28343454

RESUMO

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) patients have been reported to display deficits in action control processes. While it is known that subliminally and consciously induced conflicts interact and conjointly modulate action control in healthy subjects, this has never been investigated for ADHD. METHOD: We investigated the (potential) interaction of subliminally and consciously triggered response conflicts in children with ADHD and matched healthy controls using neuropsychological methods (event-related potentials; ERPs) to identify the involved cognitive sub-processes. RESULTS: Unlike healthy controls, ADHD patients showed no interaction of subliminally and consciously triggered response conflicts. Instead, they only showed additive effects as their behavioural performance (accuracy) was equally impaired by each conflict and they showed no signs of task-goal shielding even in cases of low conflict load. Of note, this difference between ADHD and controls was not rooted in early bottom-up attentional stimulus processing as reflected by the P1 and N1 ERPs. Instead, ADHD showed either no or reversed modulations of conflict-related processes and response selection as reflected by the N2 and P3 ERPs. CONCLUSION: There are fundamental differences in the architecture of cognitive control which might be of use for future diagnostic procedures. Unlike healthy controls, ADHD patients do not seem to be endowed with a threshold which allows them to maintain high behavioural performance in the face of low conflict load. ADHD patients seem to lack sufficient top-down attentional resources to maintain correct response selection in the face of conflicts by shielding the response selection process from response tendencies evoked by any kind of distractor.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Conflito Psicológico , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Objetivos , Desempenho Psicomotor/fisiologia , Criança , Estado de Consciência/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Subliminar
3.
Contemp Clin Dent ; 3(Suppl 2): S167-71, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23230355

RESUMO

OBJECTIVES: The objective of this in vitro study was to compare the microtensile dentin bond strength (µTBS) of five seventh-generation dentin bonding agents (DBA) with fifth-generation DBA before and after thermocycling. MATERIALS AND METHODS: Ten extracted teeth were assigned to fifth generation control group (optibond solo) and each of the five experimental groups namely, Group I (G-Bond) ,Group II (S(3) Clearfil), Group III (One Coat 7.0), Group IV (Xeno V), and Group V (Optibond all in one). The crown portions of the teeth were horizontally sectioned below the central groove to expose the dentin. The adhesive resins from all groups were bonded to the teeth with their respective composites. Specimens of sizes 1 × 1 × 6 mm(3) were obtained. Fifty specimens that bonded to dentin from each group were selected. Twenty-five of the specimens were tested for debonding without thermocycling and the remaining were subjected to thermocycling followed by µTBS testing. The data were analyzed with one-way ANOVA and Dunnett's-test for comparison with the reference group(Vth Generation). RESULTS: There was no significant difference (P > 0.05) between the fifth- and seventh-generation adhesives before and after thermocycling. The results of our study showed significantly higher value (P < 0.05) of µTBS of seventh-generation Group II (Clearfil S(3)) compared to the fifth-generation before and after thermocycling. CONCLUSION: The study demonstrated that the Clearfil S(3) bond had the highest µTBS values. In addition, of the five tested seventh-generation adhesive resins were comparable to the fifth-generation DBA.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672477

RESUMO

Objective: To investigate hepatoprotective activity of the methanolic extract of Fagonia indica Burm. on CCl4 induced hepatotoxicity in albino rats. Methods: Animals in Group 1 served as vehicle control, Group 2 served as hepatotoxin (CCl4 2ml/kg, s.c) treated group, Group 3 served as standard (Silymarin 50mg/kg, p.o.) treated group. Group4 and 5 served as methanolic extract of Fagonia indica (MEFI) in different doses (200 mg/kg and 400 mg/kg b.w., p.o).The degree of protection was determined by measuring levels of biochemical marker like SGOT, SGPT, ALP, Bilirubin (Total & Direct) and Cholesterol. The histopathological studies also show the hepatic protection of the test extracts. Results: The levels of the biochemical parameters such as SGPT, SGOT, ALP, Total bilirubin, Direct bilirubin and Cholesterol were significantly increased in CCl4 treated rats when compared with the normal group (P<0.05), but the MEFI (400 mg/kg, bw) treated rats showed maximum reduction of SGOT (114.83±1.51), SGPT (164.33±1.25), ALP (154.83±1.53), Total bilirubin (1.55±0.01), Direct bilirubin (0.65±0.009) and Cholesterol (193.00±1.06) in a significant manner. Histopathological studies also reveal the hepatoprotection property of MEFI in a dose dependent manner. Conclusions: These results suggest that MEFI in different doses showed significant hepatoprotective activity against CCl4 induced hepatotoxicity and this might be due to the presence of flavonoids and tannins. Further research is sought to explore the exact mechanism of action and phytoconstituents responsible for the pharmacological response.

5.
Bioorg Med Chem Lett ; 20(1): 137-40, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19932963

RESUMO

Species specific conversion of the lead PDE4 inhibitor 1 to the quinolone 3 was identified as the major route of metabolism in the cynomolgus monkey. Modification of the template to give the cinnoline 9 retained potency and selectivity, and greatly improved the pharmacokinetic profile in the cynomolgus monkey compared with 1. Additional SAR studies aimed at improving the solubility of 9 are also described.


Assuntos
Compostos Heterocíclicos com 2 Anéis/química , Inibidores da Fosfodiesterase 4 , Quinolinas/química , Administração Oral , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/farmacocinética , Macaca fascicularis , Quinolinas/síntese química , Quinolinas/farmacocinética , Ratos , Solubilidade , Relação Estrutura-Atividade
6.
Mol Aspects Med ; 28(5-6): 453-80, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17400288

RESUMO

Dietary factors and environmental pollutants initiate signaling cascades that converge on AhR:Nrf2:NF-kappaB transcription factor (TF) networks and, in turn, affect the health of the organism through its effects on the expression of numerous genes. Reactive oxygen metabolites (ROMs) have been hypothesized to be common mediators in these pathways. alpha-Tocopherol (AT) is a potent, lipophilic, scavenger of ROMs in vitro and has been hypothesized to be a major chain-breaking anti-oxidant in lipoproteins and biological membranes in vivo. The lung offers a vital organ to test the various postulated actions of AT in vivo. Lung AT concentrations can be manipulated by several methods that include dietary and genetic techniques. In this study we have used mice with severe AT deficiency inflicted at birth by the deletion of AT transfer protein (ATTP) which is abundantly expressed in the liver and regulates systemic concentrations of AT. Mice and humans deficient in ATTP are AT deficient. Female ATTP-deficient (ATTP-KO) mice and their congenic ATTP normal (WT) mice fed a diet containing 35 IU AT/kg diet were used to test our hypothesis. The mice (n=5/group) were exposed to either air or cigarette smoke (CS, total suspended particles 60 mg/m(3), 6h/day), a source of ROM, for 3 or 10 days. Post-exposure lung tissue was dissected, RNA extracted from each lung and it was pooled group-wise and processed for GeneChip analysis (Affymetrix 430A 2.0). Differential analysis of the transcriptomes ( approximately 16,000 mRNAs) identified CS sensitive genes that were modulated by lung AT-concentration. CS activated AhR driven genes such as cyp1b1 whose induction was augmented in CS-exposed, AT-deficient lungs. However, CS-induced expression of some of the Nrf2 driven genes was not potentiated in the AT-deficient lungs. Largest clusters of CS-AT sensitive genes were lymphocyte and leukocyte specific genes. These gene-clusters included those encoding cytokines and immunoglobulins, which were repressed by CS and were modulated by lung AT concentrations. Our genome-wide analysis suggests reciprocal regulation of xenobiotic and immune response genes by CS and a modulatory role of lung AT concentration on the expression of these clusters of genes. These data suggest that in vivo network of AT, AT-metabolites and ATTP affects the transcription of genes driven by AhR, Nrf2 and NF-kappaB, transcription factor networks that transduce cellular metabolic signals and orchestrate adaptive responses of lungs to inhaled environmental pollutants.


Assuntos
Proteínas de Transporte/metabolismo , Redes Reguladoras de Genes , Pulmão/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Fumaça , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Cromossomos de Mamíferos/metabolismo , Citocromo P-450 CYP1B1 , Feminino , Regulação da Expressão Gênica , Genoma , Inflamação/genética , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos , Camundongos Knockout , Modelos Biológicos , NAD(P)H Desidrogenase (Quinona) , NADPH Desidrogenase/genética , NADPH Desidrogenase/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo
7.
Pharmacopsychiatry ; 36 Suppl 1: S95-9, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-13130396

RESUMO

Supplementation of diets with plant extracts such as ginkgo biloba extract (EGb 761) (definition see editorial) for health and prevention of degenerative diseases is popular. However, it is often difficult to analyse the biological activities of plant extracts due to their complex nature and the possible synergistic and/or antagonistic effects of their components. Genome-wide expression monitoring with high-density oligonucleotide arrays provides one way to examine the molecular targets of plant extracts and may prove a useful tool in evaluating their therapeutic claims. Here, we will briefly describe some of our work on the effect of EGb 761 on differential gene expression in relation to its potential anti-carcinogenic, photoprotective and neuromodulatory properties.


Assuntos
Expressão Gênica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Relação Dose-Resposta a Droga , Feminino , Ginkgo biloba , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Extratos Vegetais/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
8.
Biofactors ; 15(1): 39-52, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11673643

RESUMO

The objective of the present study was to characterize the action of Ginkgo biloba extract (EGb761) and its sub-fractions on glutathione homeostasis in a human keratinocyte cell culture model. Cells were incubated with EGb761, its purified flavonoid (quercetin, kaempferol, rutin) or terpenoids (gingkolides A, B, C, J, bilobalide) constituents or the vehicle for up to 72 hours. Incubation of keratinocytes with the purified flavonoids or terpenoids did not affect cellular GSH levels. However, EGb761 treatment (up to 200 microg/ml) resulted in a dose-dependent increase of cellular GSH. Western blot analysis of extracts from cells treated with EGb761 revealed increased levels of the catalytic subunit of gamma-glutamylcysteinyl synthetase (gamma-GCS), the rate-limiting enzyme in GSH synthesis. The abundance of mRNA for the catalytic subunit (assayed by RT-PCR) was also increased by the treatment with EGb761. Increased levels of cellular GSH by EGb761 were also observed in other cell lines including those from human bladder and liver as well as in murine macrophages indicating that the induction of gamma-GCS mRNA, protein and GSH may be an ubiquitous effect of EGb761 in mammalian cells.


Assuntos
Ginkgo biloba , Glutationa/biossíntese , Queratinócitos/metabolismo , Extratos Vegetais/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Transformada , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Homeostase , Humanos , Queratinócitos/efeitos dos fármacos , NF-kappa B/metabolismo , Fatores Nucleares Respiratórios , Peróxidos/análise , RNA Mensageiro/análise , Transativadores/metabolismo , Fator de Transcrição AP-1/metabolismo , alfa-Tocoferol/análise
9.
Biochem Biophys Res Commun ; 285(2): 470-5, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11444866

RESUMO

To examine the molecular events associated with selenium (Se) and vitamin E (VE) deficiency, we applied cDNA array technology to define the transcriptional response in the liver of Se- and VE-deficient rats. VE deficiency alone did not induce any significant changes in expression profile among the genes evaluated. Se deficiency lead to a down-regulation of Se-dependent cGPx and to an induction of genes, encoding for detoxifying enzymes in liver (cytochrome P450 4B1, UDP-glucuronosyltransferase 1). Combined VE and Se deficiency was characterized by alterations in the expression level of genes encoding for proteins involved in inflammation (multispecific organic anion exporter, SPI-3 serine protease inhibitor) and acute phase response (alpha-1 acid glycoprotein, metallothionein 1). Additionally, a significant down-regulation in the expression level of genes important in the inhibition of apoptosis (defender against cell death 1 protein, Bcl2-L1), cell cycle (G1/S-specific cyclin D1) and antioxidant defense (gamma-glutamylcysteine synthetase catalytic subunit) was demonstrated. The experimental strategy identified several novel Se and VE sensitive genes.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Regulação da Expressão Gênica/fisiologia , Glutationa Peroxidase/genética , Fígado/fisiologia , Selênio/deficiência , Deficiência de Vitamina E/metabolismo , Vitamina E/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Sistema Enzimático do Citocromo P-450/biossíntese , Sistema Enzimático do Citocromo P-450/genética , Di-Hidrolipoamida Desidrogenase/biossíntese , Di-Hidrolipoamida Desidrogenase/genética , Indução Enzimática , Regulação da Expressão Gênica/efeitos dos fármacos , Glucuronosiltransferase/biossíntese , Glucuronosiltransferase/genética , Glutationa/metabolismo , Glutationa Peroxidase/biossíntese , Fígado/citologia , Fígado/efeitos dos fármacos , Metalotioneína/metabolismo , Ratos , Selênio/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética
10.
Bioorg Med Chem Lett ; 11(15): 1993-5, 2001 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-11454465

RESUMO

The synthesis and antiviral evaluation of unsymmetrical indolocarbazole derivatives of Arcyriaflavin A, substituted with a range of alkyl groups at the indole nitrogen, is described. Structure-activity relationships in this series against human cytomegalovirus (HCMV) replication in cell culture are reported. Compound 4b was identified as potent inhibitor of HCMV (IC(50)=19 nM), which retained activity against a range of HCMV strains including ganciclovir resistant isolates.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Carbazóis/farmacologia , Citomegalovirus/efeitos dos fármacos , Indóis/farmacologia , Replicação Viral/efeitos dos fármacos , Carbazóis/síntese química , Células Cultivadas , Resistência a Medicamentos/genética , Resistência a Medicamentos/fisiologia , Ganciclovir/farmacologia , Humanos , Indóis/síntese química , Concentração Inibidora 50 , Proteína Quinase C/antagonistas & inibidores , Relação Estrutura-Atividade
11.
Proc Natl Acad Sci U S A ; 98(12): 6577-80, 2001 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-11381109

RESUMO

Extracts of Ginkgo biloba leaves are consumed as dietary supplements to counteract chronic, age-related neurological disorders. We have applied high-density oligonucleotide microarrays to define the transcriptional effects in the cortex and hippocampus of mice whose diets were supplemented with the herbal extract. Gene expression analysis focused on the mRNAs that showed a more than 3-fold change in their expression. In the cortex, mRNAs for neuronal tyrosine/threonine phosphatase 1, and microtubule-associated tau were significantly enhanced. Hyperphosphorylated tau is the major constituent of the neurofibrillary tangles in the brains of Alzheimer's disease patients. The expression of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-2, calcium and chloride channels, prolactin, and growth hormone (GH), all of which are associated with brain function, were also up-regulated. In the hippocampus, only transthyretin mRNA was upregulated. Transthyretin plays a role in hormone transport in the brain and possibly a neuroprotective role by amyloid-beta sequestration. This study reveals that diets supplemented with Ginkgo biloba extract have notable neuromodulatory effects in vivo and illustrates the utility of genome-wide expression monitoring to investigate the biological actions of complex extracts.


Assuntos
Encéfalo/efeitos dos fármacos , Ginkgo biloba , Plantas Medicinais , Transcrição Gênica/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Feminino , Hormônio do Crescimento/genética , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Pré-Albumina/genética , Receptores de AMPA/genética
12.
Artigo em Inglês | MEDLINE | ID: mdl-11282330

RESUMO

The aim of the present study was to ascertain the effects of training and exhaustive exercise on mitochondrial capacities to oxidize pyruvate, 2-oxoglutarate, palmitoylcarnitine, succinate and ferrocytochrome c in various tissues of the rat. Endurance capacity was significantly increased (P<0.01) by an endurance training program over a period of 5-6 weeks. The average run time to exhaustion was 214.2+/-23.8 min for trained rats in comparison with 54.5+/-11.7 min for their untrained counterparts. Oxidative capacities were reduced in liver (P<0.05) and brown adipose tissue (P<0.05) as a result of endurance training. On the contrary, the oxidative capacity of skeletal muscle was slightly increased and that of heart almost unaffected except for the oxidation of palmitoylcarnitine, which was significantly reduced (P<0.05) as a result of training.


Assuntos
Enzimas/metabolismo , Mitocôndrias/enzimologia , Condicionamento Físico Animal , Resistência Física , Tecido Adiposo Marrom/metabolismo , Animais , Peso Corporal , Grupo dos Citocromos c/metabolismo , Feminino , Ácidos Cetoglutáricos/metabolismo , Fígado/metabolismo , Músculo Esquelético , Miocárdio/metabolismo , Oxirredução , Palmitoilcarnitina/metabolismo , Ácido Pirúvico/metabolismo , Ratos , Ratos Sprague-Dawley , Ácido Succínico/metabolismo
13.
Free Radic Res ; 33(6): 831-49, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11237105

RESUMO

Supplementation of diets with plant extracts for health and prevention of degenerative diseases is popular. However the molecular basis of their therapeutic potentials are poorly defined. We hypothesized that in vitro assays that enable quantitative analysis of the gene expression profiles combined with targeted biochemical analysis can identify the potential effects of phytochemicals. The hypothesis was tested by application of GeneChips to define mRNA expressions of a human bladder cancer cell line incubated with a flavonoid containing extract of Ginkgo biloba leaves. The analysis of the transcriptional response revealed a net activation of transcription. Functional classification of the affected mRNAs showed the largest changes in the abundance of mRNAs for intracellular vesicular transport, mitochondria, transcription and antioxidants. The transcripts for hemeoxygenase-1, mitochondrial superoxide dismutase and the regulatory subunit of gamma-glutamyl-cysteinyl synthetase and their encoded proteins were elevated. The extract also increased intracellular glutathione, the transcripts for DNA repair and synthesis, and decreased 3H-thymidine incorporation. These results demonstrate that a flavonoid containing extract initiates an adaptive transcriptional response that augments the "antioxidant status" of the cells and inhibits DNA damage. These in vitro studies using GeneChips demonstrated a promising strategy for identifying nutritional supplement induced cellular responses that may have a role in counteracting chronic human diseases.


Assuntos
Antioxidantes/metabolismo , Ginkgo biloba/química , Complexo de Golgi/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , RNA Mensageiro/análise , Neoplasias da Bexiga Urinária/metabolismo , Divisão Celular , DNA/biossíntese , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Flavonoides/farmacologia , Citometria de Fluxo , Glutamato-Cisteína Ligase/genética , Glutationa/metabolismo , Complexo de Golgi/fisiologia , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase-1 , Humanos , Proteínas de Membrana , Superóxido Dismutase/genética , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/patologia
14.
Bioorg Med Chem ; 7(6): 1067-74, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10428375

RESUMO

In our search for new, safer anti-HCMV agents, we discovered that the natural product Arcyriaflavin A (la) was a potent inhibitor of HCMV replication in cell culture. A series of analogues (symmetrical indolocarbazoles) was synthesised to investigate structure activity relationships in this series against a range of herpes viruses (HCMV, VZV, HSV1, and 2). This identified a number of novel, selective and potent inhibitors of HCMV, 12,13-dihydro-2,10-difluoro-5H-indolo[2,3-a]pyrrolo[3,4-c]carbazol e-5,7-(6H)-dione (1d) being the best example (IC50=40 nM, therapeutic index > 1450). Compounds described in this series were generally poor inhibitors of protein kinase C betaII, and no correlation was found between the ability to inhibit HCMV and the enzyme PKC.


Assuntos
Antivirais/síntese química , Carbazóis/farmacologia , Citomegalovirus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacologia , Carbazóis/química , Divisão Celular/efeitos dos fármacos , Chlorocebus aethiops , Citomegalovirus/fisiologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Herpesviridae/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Ratos , Relação Estrutura-Atividade , Células Vero
16.
J Chromatogr B Biomed Appl ; 677(1): 194-8, 1996 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-8925096

RESUMO

The binding properties of six indolocarbazole derivative have been measured using immobilised human serum albumin (HSA) in an HPLC column. The compounds showed very strong binding to HSA which necessitated the application of a 30 to 40% concentration of 2-propanol in the mobile phase. This represents a much higher concentration than is recommended by the column manufacturers. This HSA column had not changed its binding property when it was used again with 4% 2-propanol and 96% phosphate buffer. The binding parameters were estimated by extrapolation to 0% 2-propanol and were above 99% for each indolocarbazole derivative. The correlation analysis, including the calculated octanol/water partition coefficient (log P), pKa values as well as measured reversed-phase retention data of the compounds revealed that the extremely strong binding can be explained by the hydrophobic and acidic properties of the compounds.


Assuntos
Antivirais/farmacocinética , Carbazóis/farmacocinética , Indóis/farmacocinética , Antivirais/análise , Carbazóis/análise , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Humanos , Indóis/análise , Ligação Proteica , Albumina Sérica , Solubilidade
17.
Brain Res ; 653(1-2): 258-66, 1994 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-7982059

RESUMO

Neuronal voltage-sensitive calcium channels (VSCCs) are a diverse family of proteins that regulate entry of Ca2+ into neurons. Selective antagonists of VSCCs have proven to be powerful pharmacological tools for identifying and characterizing these channels. A new VSCC antagonist, SNX-230 (also known as omega-conopeptide MVIIC), binds with high affinity to receptors in rat brain and blocks one or more high-threshold VSCCs that are neither L- nor N-type. We have defined the neuroanatomical distribution of the high-affinity non-L, non-N VSCC receptors for SNX-230 using [125I]SNX-230 bound to rat brain sections and compared it with that of [125I]SNX-111, a reversible blocker of N-type VSCCs. Highest densities of binding for both ligands were seen in areas rich in synaptic connections, such as the oriens, radiatum and molecular layers of the hippocampus. In general, the density of [125I]SNX-230-binding was higher in cerebellum compared with that in forebrain. In contrast, this general distribution of density was reversed for [125I]SNX-111. In the glomeruli of the olfactory bulb, binding of [125I]SNX-230 was undetectable compared with the high density of [125I]SNX-111-binding. Differential localization of the two ligands was also seen in cervical spinal cord. The clearly different localization of [125I]SNX-230 compared with that of [125I]SNX-111 in the olfactory bulb and spinal cord suggested that the binding sites for [125I]SNX-230 in other brain regions, while co-localized macroscopically, are also distinct from those for [125I]SNX-111. This was confirmed when addition of saturating concentrations of SNX-111 did not affect the distribution pattern of [125I]SNX-230-binding.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Encéfalo/metabolismo , Peptídeos/metabolismo , Receptores de Superfície Celular/metabolismo , ômega-Conotoxinas , Animais , Autorradiografia , Bloqueadores dos Canais de Cálcio/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , ômega-Conotoxina GVIA
18.
J Nutr ; 120(8): 909-16, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2199635

RESUMO

We tested the hypothesis that a very rapid improvement in exercise performance of iron-deficient rats after treatment with iron might reveal a rate-limiting role of ionic iron as an enzyme cofactor in energy metabolism. Rats were given iron-deficient or control diets after weaning at 21 d of age and intraperitoneal iron dextran (50 mg/kg) at 45 d of age. Time to fatigue during an easy walking exercise (endurance) was measured 15 and 18 h after iron dextran or saline injection. Endurance increased more than threefold compared to the saline-treated, iron-deficient animals without a significant change in hemoglobin concentration. This prompt improvement suggests that lack of cofactor iron might play a metabolically important role in impairing exercise performance in the severely iron-deficient rat.


Assuntos
Deficiências de Ferro , Esforço Físico/fisiologia , Oxirredutases do Álcool/metabolismo , Anemia Hipocrômica/tratamento farmacológico , Anemia Hipocrômica/fisiopatologia , Animais , Peso Corporal , Carnitina/farmacologia , Metabolismo Energético , Feminino , Hemoglobinas/metabolismo , Ferro/uso terapêutico , Complexo Cetoglutarato Desidrogenase/metabolismo , Músculos/enzimologia , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Esforço Físico/efeitos dos fármacos , Piruvato Oxidase/metabolismo , Ratos , Ratos Endogâmicos
19.
J Appl Physiol (1985) ; 64(1): 115-9, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3356628

RESUMO

To examine the effects of increased O2 utilization on the glutathione antioxidant system in blood, eight moderately trained male volunteers were exercised to peak O2 consumption (VO2peak) and for 90 min at 65% of VO2peak on a cycle ergometer. Blood samples were taken during exercise, and for up to 4 days of recovery from submaximal exercise. During exercise to VO2peak, blood reduced glutathione (GSH) and total glutathione [GSH + oxidized glutathione (GSSG)] did not change significantly. Lactate (L), pyruvate (P), and L/P increased significantly from rest values (P less than 0.01). During prolonged submaximal exercise, GSH decreased 60% from control, and GSSG increased 100%. Total glutathione, glucose, pyruvate, and lactate concentrations and L/P did not change significantly during sustained exercise. During recovery, GSH and GSH/GSSG increased from exercise levels and significantly overshot preexercise levels, reaching maximum values after 3 days. Oxidation of GSH during submaximal exercise and its reduction in recovery suggest increased formation of active O2-. species in blood during physical exercise in moderately trained males.


Assuntos
Glutationa/sangue , Esforço Físico , Adulto , Glicemia/metabolismo , Glutationa/metabolismo , Humanos , Lactatos/sangue , Masculino , Oxirredução , Consumo de Oxigênio , Piruvatos/sangue
20.
J Appl Physiol (1985) ; 63(6): 2532-5, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3436884

RESUMO

Increased O2 metabolism imposed by physical exercise is likely to augment the production of active O2 species that have been shown to react with lipids, proteins, and DNA. Antioxidants and antioxidant enzymes, such as the selenium enzyme glutathione peroxidase, minimize or prevent such potentially toxic reactions. This study shows that selenium deficiency decreases glutathione peroxidase activity in liver and muscle (less than 80%, P less than 0.001), increases total glutathione in liver, muscle, and plasma (P less than 0.05) and increases muscle cytochrome oxidase activity, and ubiquinone content (P less than 0.05) but has no effect on endurance capacity. Exercise to exhaustion resulted in a significant (P less than 0.001) elevation of total and oxidized glutathione (GSSG) and a significant (P less than 0.05) decrease of vitamin E in plasma of control and selenium-deficient rats. Acute exercise also increased tissue GSSG levels in both control and selenium-deficient groups of rats. Hence, despite a large depletion of selenium-deficient glutathione peroxidase, pronounced oxidation of glutathione to GSSG can be produced by the increased oxidative metabolism during physical exercise. The results suggest that the residual glutathione peroxidase activity is sufficient to detoxify hydroperoxides in exercising selenium-deficient animals and to prevent the impairment of endurance capacity.


Assuntos
Antioxidantes/análise , Glutationa Peroxidase/metabolismo , Resistência Física , Esforço Físico , Selênio/deficiência , Animais , Glutationa/análise , Fígado/análise , Fígado/enzimologia , Masculino , Músculos/análise , Músculos/enzimologia , Ratos , Ratos Endogâmicos , Ubiquinona/análise , Vitamina E/análise
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