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1.
J Intern Med ; 288(5): 507-517, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32715520

RESUMO

Clonal haematopoiesis results from acquired mutations in haematopoietic stem and progenitor cells (HSPCs). These mutations can confer the HSPC with a competitive advantage, leading to their clonal expansion within the limiting bone marrow niche. This process is often insufficient to produce a haematologic malignancy; however, the expanding HSPC clones increasingly give rise to progeny leucocytes whose phenotypes can be altered by the somatic mutations that they harbour. Key findings from multiple human studies have shown that clonal haematopoiesis in the absence of overt haematologic alterations is common amongst the ageing population and associated with mortality and cardiovascular disease. Key findings from experimental studies have provided evidence for a causative role for clonal haematopoiesis in cardiovascular diseases, and aspects of these mechanisms have been elucidated. Whilst our understanding of the impact and biology of clonal haematopoiesis is in its infancy, analyses of some of the most commonly mutated driver genes suggest promising clinical scenarios involving the development of personalized therapies with immunomodulatory drugs that exploit the perturbation caused by the particular mutation. Herein, we review the accumulating epidemiological and experimental evidence, and summarize our current understanding of the importance of clonal haematopoiesis as a new causal risk factor for atherosclerotic cardiovascular disease and heart failure.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Hematopoiese Clonal , Envelhecimento/fisiologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/terapia , Células-Tronco Hematopoéticas/fisiologia , Humanos , Imunomodulação , Mutação , Células-Tronco/fisiologia
2.
Oral Dis ; 23(4): 492-497, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28083982

RESUMO

OBJECTIVE: Halitosis is caused by volatile sulphur compounds including methyl mercaptan (CH3 SH) in the oral cavity and is a serious problem that limits interpersonal social communication. The aim of study was to evaluate the effects of reuterin-related compounds (RRCs) on halitosis-related periodontopathic bacteria in vitro. MATERIALS AND METHODS: RRC-01, RRC-02 and RRC-03 (32 and 64 µg ml-1 ) in culture media containing Fusobacterium nucleatum JCM8523 and Porphyromonas gingivalis ATCC33277 were used. The effects of RRCs on CH3 SH production and detectable odour by F. nucleatum and P. gingivalis were examined by CH3 SH production assay and organoleptic test, respectively. The number of bacterial cells was also measured using an ATP assay. In P. gingivalis treated with RRCs, the expression of mgl gene, which is responsible for CH3 SH production, was examined by qRT-PCR. RESULTS: CH3 SH production and the score of detectable odour from F. nucleatum and P. gingivalis culture media containing RRCs were significantly lower than that without RRCs (P < 0.05). The expression of mgl gene in P. gingivalis was significantly downregulated by RRC-01 (P < 0.01), but not by RRC-02 or RRC-03. CONCLUSIONS: RRCs are potent oral care products for preventing halitosis via reducing CH3 SH production.


Assuntos
Antibacterianos/farmacologia , Fusobacterium nucleatum/efeitos dos fármacos , Gliceraldeído/análogos & derivados , Halitose/microbiologia , Odorantes/análise , Porphyromonas gingivalis/efeitos dos fármacos , Propano/farmacologia , Antibacterianos/uso terapêutico , Biomarcadores/metabolismo , Fusobacterium nucleatum/metabolismo , Gliceraldeído/farmacologia , Gliceraldeído/uso terapêutico , Halitose/prevenção & controle , Humanos , Porphyromonas gingivalis/metabolismo , Propano/uso terapêutico , Compostos de Sulfidrila/metabolismo
4.
Clin Exp Dermatol ; 38(1): 66-70, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23083105

RESUMO

BACKGROUND: Psoriasis represents one of the T-helper (Th)17-mediated autoimmune diseases, and has been shown to be associated with metabolic syndrome (MetS). It has been reported that some adipokines and Th17-related cytokines are altered in patients with psoriasis. AIM: To examine the relationship between levels of adipokines and Th17-related cytokines in the serum of patients with psoriasis compared with healthy controls. METHODS: We enrolled 30 patients with psoriasis and 30 normal controls in the study, and used ELISA to measure serum adipokines and Th17-related cytokines. The association between each adipokine and each cytokine was determined using Pearson correlation analysis. Multiple regression analysis using all adipokines and Th17-related cytokines as covariates was also performed. RESULTS: Pearson correlation analysis showed a strong positive association between chemerin and resistin levels and between adiponectin and high molecular weight adiponectin in normal controls. By contrast, in patients with psoriasis, resistin levels were significantly positively associated with tumour necrosis factor-α, while there was a strong negative association between retinol binding protein-4 and interleukin (IL)-6 levels. Interestingly, a marked positive correlation between IL-22 and adiponectin was also found in patients with psoriasis. Leptin levels correlated positively with IL-6 in patients with psoriasis, but this did not reach significance. The correlations identified by the multiple regression analyses were almost identical to those from the Pearson analyses. CONCLUSIONS: These data suggest that distinct interaction between adipokines and Th17 cytokines is involved in the pathogenesis of psoriasis.


Assuntos
Adipocinas/sangue , Citocinas/sangue , Psoríase/sangue , Células Th17/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/imunologia , Análise de Regressão , Índice de Gravidade de Doença
5.
Horm Metab Res ; 44(1): 15-20, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22205568

RESUMO

Glucocorticoid (GC) excess promotes adipose tissue accumulation, and 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) plays an important role in the local amplification of GC. Therefore, in this study, we investigated the effects of carbenoxolone (CBX), an 11ß-HSD1 inhibitor, on morphological changes in visceral fat, and the expression of genes involved in adipogenesis and lipid metabolism in high-fat (HF) diet-fed mice. Mice were fed a HF diet from 5 weeks of age. At 10 weeks of age, the mice received an intraperitoneal injection of CBX or vehicle every day for 2 weeks. CBX decreased body weight and visceral fat mass, and improved insulin sensitivity in HF-fed mice. This was accompanied by reduced adipocyte size and a decrease in large-sized adipocytes in visceral fat. The expression of adipogenesis (PPARγ and C/EBPα), glucose transport (GLUT4) and lipid metabolism (LPL, ATGL, and HSL)-related genes were suppressed in CBX mice. CBX treatment induced beneficial morphological changes in visceral fat and decreased the expression of adipogenesis, glucose transport and lipid metabolism-related genes. These findings reveal a potential mechanism underling the effects of CBX on reduced fat accumulation and improved insulin sensitivity.


Assuntos
Adipogenia/genética , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/metabolismo , Carbenoxolona/farmacologia , Regulação para Baixo/efeitos dos fármacos , Glucose/metabolismo , Metabolismo dos Lipídeos/genética , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Regulação para Baixo/genética , Comportamento Alimentar/efeitos dos fármacos , Teste de Tolerância a Glucose , Insulina/metabolismo , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Perfusion ; 27(1): 72-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22005885

RESUMO

We report here Japan's first pediatric perfusion survey. It covers practices from January 2007 through December 2009. Of the 70 congenital heart centers contacted, 53 (76%) completed the survey. They reported performing 3,379 pediatric cardiopulmonary bypass (CPB) procedures in 2009, 3,408 in 2008, and 3,358 in 2007.Twenty-eight percent of all centers used CPB circuits with a priming volume between 151-200 ml. All centers used pre-bypass ultrafiltration and only 6% used retrograde autologous priming. A biomaterial-coated circuit was used by 78% of the centers, a roller pump as the arterial pump by 91%, vacuum-assisted venous drainage by 39%, dilutional ultrafiltration by 48%, and modified ultrafiltration at the end of the procedure by 30%. A regional oxygen saturation monitor was used by 69% of the centers and high flow (150-200 ml/kg/min) management with alpha-stat blood gas control was standard during moderate to normothermic CPBs. Crystalloid cardioplegia solution was used as myocardial protection by 56% of the centers, electronic recording of monitoring data by 51%. The centers performed 98 pediatric extracorporeal membrane oxygenation procedures in 2007, 109 in 2008, and 119 in 2009; 58% of the centers used a centrifugal pump. This survey provides a description of the current practice in Japan. Future surveys will identify trends and rate of change in practice.


Assuntos
Ponte Cardiopulmonar/métodos , Ponte Cardiopulmonar/estatística & dados numéricos , Coleta de Dados , Cardiopatias Congênitas/cirurgia , Pediatria , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Humanos , Japão , Estudos Retrospectivos , Inquéritos e Questionários , Ultrafiltração/métodos , Ultrafiltração/estatística & dados numéricos
7.
Perfusion ; 27(3): 225-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22249964

RESUMO

Extracorporeal membrane oxygenation (ECMO) has emerged as an effective mechanical support following cardiac surgery with respiratory and cardiac failure. However, there are no clear indications for ECMO use after pediatric cardiac surgery. We retrospectively reviewed medical records of 76 pediatric patients [mean age, 10.8 months (0-86); mean weight, 5.16 kg (1.16-16.5)] with congenital heart disease who received ECMO following cardiac surgery between January 1997 and October 2010. Forty-five patients were treated with an aggressive ECMO approach (aggressive ECMO group, April 2005-October 2010) and 31 with a delayed ECMO approach (delayed ECMO group, January 1997-March 2005). Demographics, diagnosis, operative variables, ECMO indication, and duration of survivors and non-survivors were compared. Thirty-four patients (75.5%) were successfully weaned from ECMO in the aggressive ECMO group and 26 (57.7%) were discharged. Conversely, eight patients (25.8%) were successfully weaned from ECMO in the delayed ECMO group and two (6.5%) were discharged. Forty-five patients with shunted single ventricle physiology (aggressive: 29 patients, delayed: 16 patients) received ECMO, but only 15 (33.3%) survived and were discharged. The survival rate of the aggressive ECMO group was significantly better when compared with the delayed ECMO group (p<0.01). Also, ECMO duration was significantly shorter among the aggressive ECMO group survivors (96.5 ± 62.9 h, p<0.01). Thus, the aggressive ECMO approach is a superior strategy compared to the delayed ECMO approach in pediatric cardiac patients. The aggressive ECMO approach improved our outcomes of neonatal and pediatric ECMO.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Oxigenação por Membrana Extracorpórea/métodos , Cardiopatias Congênitas/cirurgia , Criança , Pré-Escolar , Intervalo Livre de Doença , Oxigenação por Membrana Extracorpórea/efeitos adversos , Feminino , Cardiopatias Congênitas/mortalidade , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Taxa de Sobrevida
8.
Clin Exp Immunol ; 166(2): 164-70, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21985362

RESUMO

Thymoma-associated multi-organ autoimmunity is a rare, autoimmune disease that causes colitis, liver dysfunction and cutaneous graft-versus-host (GVH)-like skin damage. This paraneoplastic autoimmune disorder may be due to inadequate T cell selection in the tumour environment of the thymus. Although sporadic case reports have revealed its clinical features, little is known about its pathological mechanism. By comparing the skin-infiltrating T cell subsets with those of GVH disease (GVHD) and other inflammatory skin diseases, we sought to elucidate the pathological mechanism of thymoma-associated multi-organ autoimmunity. Histopathological and immunohistochemical analysis of skin biopsies was performed for three patients with thymoma-associated multi-organ autoimmunity. Histopathological findings of thymoma-associated multi-organ autoimmunity were indistinguishable from those of patients with acute GVHD, although the aetiologies of these diseases are completely different. The frequency of regulatory T cells (T(regs)) is reduced in cutaneous lesions and CD8+ cytotoxic T lymphocytes that massively infiltrate into the epidermis of patients with thymoma-associated multi-organ autoimmunity. Additionally, the ratio of T helper type 17 (Th17) cells to CD4+ cells in patients with thymoma-associated multi-organ autoimmunity and acute GVHD was higher than that in healthy controls, but similar to that in psoriasis vulgaris patients. Similarity of the skin-infiltrating T cell subsets with those of acute GVHD suggested that skin damage in patients with thymoma-associated multi-organ autoimmunity might be induced by self-reactive cytotoxic T lymphocytes under the diminished suppressive capacity of T(regs).


Assuntos
Autoimunidade/imunologia , Linfócitos T Reguladores/imunologia , Timoma/imunologia , Timoma/patologia , Adulto , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Humanos , Contagem de Linfócitos , Psoríase/imunologia , Psoríase/patologia , Pele/imunologia , Pele/patologia , Dermatopatias/imunologia , Dermatopatias/metabolismo , Dermatopatias/patologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Timo/imunologia , Timo/patologia , Microambiente Tumoral
10.
Horm Metab Res ; 43(3): 178-82, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21264794

RESUMO

Intrauterine growth restriction (IUGR) is associated with a substantially greater incidence of metabolic syndrome in adulthood. Animal studies have shown that IUGR offspring are hyperphagic during the early postnatal period and therefore exhibit obesity. The molecular mechanisms underlying food intake regulation in the gastrointestinal tract have not been clarified in IUGR. In the present study, we utilized a rat model of IUGR by restricting the food intake of the mother (50% of the normal intake, ad libitum; FR group) from day 7 of gestation until delivery. Pups from undernourished mothers were fostered by control mothers. We examined the food intake and assessed the gene expressions of ghrelin, peptide YY (PYY), and cholecystokinin (CCK) in the alimentary tract of male newborns (postnatal day1) and adult offspring (age, 7 months). Compared to the offspring whose mothers received the standard diet ad libitum (CON offspring), FR offspring were hyperphagic from the weaning time until the end of the experiment, and resulted in a heavier final weight. Both newborn and adult FR offspring had higher ghrelin gene expression in the stomach and higher ghrelin plasma levels than did the controls. Although the gastrointestinal gene expressions and plasma levels of the anorexic peptides, PYY and CCK, were elevated in the FR newborns, they decreased in the FR adults. Our findings suggest that the altered gene expressions of orexigenic and anorexigenic gut peptides in the gastrointestinal tract in the maternal undernutrition-induced IUGR offspring provide a potential mechanism to explain hyperphagia and obesity seen in these offspring.


Assuntos
Colecistocinina/genética , Retardo do Crescimento Fetal/genética , Trato Gastrointestinal/metabolismo , Grelina/genética , Hiperfagia/genética , Peptídeo YY/genética , Regulação para Cima , Adulto , Animais , Animais Recém-Nascidos , Peso Corporal , Colecistocinina/sangue , Modelos Animais de Doenças , Ingestão de Alimentos , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/fisiopatologia , Trato Gastrointestinal/crescimento & desenvolvimento , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Grelina/sangue , Humanos , Hiperfagia/sangue , Hiperfagia/fisiopatologia , Masculino , Peptídeo YY/sangue , Ratos , Ratos Sprague-Dawley
11.
Horm Metab Res ; 42(11): 821-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20711951

RESUMO

Peroxisomal proliferator-activated receptors (PPARs) play an important role in the regulation of lipid metabolism. The aim of this study was to investigate the effects of a maternal high-fat (HF) diet on serum lipid concentration and PPAR gene expression in liver and adipose tissue in the early life of the rat offspring. Female Sprague-Dawley rats were fed either an HF or control (CON) diet 6 weeks before mating and throughout gestation and lactation. Blood and tissue samplings of male offspring were carried out at birth or weaning. Birth weights were similar and serum triglyceride (TG) and nonesterified fatty acid (NEFA) levels showed no significant difference between HF and CON newborns, despite greatly increased hepatic PPARα mRNA expression in the HF newborns (p<0.05). Both HF newborns and weanlings revealed significantly decreased hepatic PPARγ expression compared with controls (p<0.0001). Hepatic PPARα expression in the HF weanlings was reduced markedly compared with CON weanlings (p<0.0001) and showed a negative correlation with serum TG levels (r=-0.743, p<0.05). However, epididymal expression of PPARγ in the HF weanlings was upregulated significantly compared with controls (p<0.05) and demonstrated a positive correlation with epididymal fat mass (r=0.733, p<0.05). These were accompanied by obesity as well as a rise in serum TG by 79% (p<0.05) and NEFA concentration by 36% (p<0.05) in these HF weanlings. Our findings suggest that maternal HF diet leads to alterations in PPAR gene expression in the weanling offspring, which is associated with the disturbed lipid homeostasis.


Assuntos
Gorduras na Dieta/farmacologia , Lipídeos/sangue , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Feminino , Ratos , Ratos Sprague-Dawley
12.
Med Vet Entomol ; 24(4): 375-81, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20946439

RESUMO

Maggot debridement therapy (MDT) is a method for the treatment of intractable, infected and necrotic wounds. In MDT, sterile larvae of Lucilia sericata Meigen (Diptera: Calliphoridae) are applied to infected wounds, where they exert antibacterial effects. Once the larvae are placed in the wound, they are no longer germ-free. This study analysed the influence of infected environments on larval antibacterial activities. Sterile larvae were mixed in a test tube containing a bacterial suspension of Staphylococcus aureus or Pseudomonas aeruginosa, transferred to liver puree agar, and incubated at 25 °C for set periods. To collect the larval extracts, the incubated larvae were transferred to a test tube containing phosphate buffered saline (PBS), cut into multiple pieces with scissors, and centrifuged. The supernatant was used to test antibacterial activities. The results showed that infected larvae had better antibacterial capacities than sterile larvae. Antibacterial activities were induced by pretreatment with a single bacterial species, S. aureus or P. aeruginosa, within 24 h and 12 h, respectively, and disappeared after 36 h. The activities were effective against S. aureus, but not against P. aeruginosa. This natural infection model is very similar to the clinical wound context in MDT and will be a powerful tool with which to study the antibacterial activities of L. sericata larvae in MDT.


Assuntos
Antibacterianos/metabolismo , Antibacterianos/farmacologia , Dípteros/química , Dípteros/microbiologia , Meio Ambiente , Staphylococcus aureus/efeitos dos fármacos , Animais , Dípteros/metabolismo , Humanos , Larva , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/metabolismo , Fatores de Tempo , Infecção dos Ferimentos/microbiologia
13.
Rev Sci Instrum ; 91(2): 023706, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113388

RESUMO

We develop an x-ray imaging system based on Talbot-Lau interferometry equipped with a mechanical structure for retracting and rotating gratings from the optical axis, which enables not only x-ray phase contrast imaging but also conventional x-ray imaging with high-magnification such as microcomputed tomography (µCT). We investigate the characterization of carbon fiber reinforced plastic (CFRP) laminates using this apparatus. Microcracks and fiber orientations are visualized in the dark-field images. Compared with the obtained µCT images, the relationship between the CFRP microstructures and the contrasts in the dark-field images are recognizable.

14.
Kyobu Geka ; 61(4): 287-92, 2008 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-18411691

RESUMO

The arterial switch operation (ASO) has become the primary surgical approach used for correction of transposition of the great arteries. All the prerequisites for a successful ASO were recognized in time and dealt with, which allowed general acceptation of the technique. We report on our technique for the procedure and the result to date. From January 1991 to January 2008, a total of 100 patients underwent ASO at our unit using medially-based trapdoor flap method. The neo-pulmonary artery (PA) was reconstructed using a single rectangular pericardial patch. The initial patient having intramural coronary artery died due to ischemic event after Aubert procedure. Three patients had re-right ventricular out flow tract repair (RVOTR) in a long-term follow-up period. There was no significant aortic insufficiency, no ischemic event and no lethal arrhythmia.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Vasos Coronários/cirurgia , Transposição dos Grandes Vasos/cirurgia , Seguimentos , Humanos , Recém-Nascido , Artéria Pulmonar/cirurgia
15.
Biochim Biophys Acta ; 570(1): 167-78, 1979 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-486501

RESUMO

delta-Aminolevulinic acid dehydratase (5-aminolevulinic acid hydro-lyase (adding 5-aminolevulinic acid and cyclizing), EC 4.2.1.24 purified from bovine liver in the presence of both SH-reducing reagent and zinc during the purification contained one zinc atom and eight SH groups/subunit. This preparation showed the full enzymatic activity even in the absence of thiol activator. It was found that two cysteine residues, one zinc atom and two histidine residues were involved in the active site. The enzyme was fullly active as long as two SH groups in the active site remained in the reduced form even in the absence of zinc. However, the enzymatic activity was completely lost, with a concomitant loss of bound zinc, upon oxidation of the SH groups to a disulfide bond, modification of SH groups with chemical reagents, or mercaptide formation by heavy metals. Thus, it is apparent that the activity depends on the essential SH groups. The zinc is not absolutely essential for the activity but may be required to prevent the essential SH groups from autooxidation by coordination. Binding experiments indicated that there was one binding site of zinc/subunit. Photooxidation of histidine residues diminished both enzymatic activity and bound zinc, suggesting that the histidine residues not only constituted the active site but also served as a possible ligand to zinc.


Assuntos
Fígado/enzimologia , Sintase do Porfobilinogênio/metabolismo , Zinco/metabolismo , Animais , Apoenzimas/metabolismo , Sítios de Ligação , Bovinos , Fenômenos Químicos , Química , Histidina , Oxigênio/farmacologia , Compostos de Sulfidrila/metabolismo
16.
Biochim Biophys Acta ; 678(1): 39-50, 1981 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-7306578

RESUMO

delta-Aminolevulinic acid dehydratase (porphobilinogen synthase; 5-aminolevulinate hydro-lyase, EC 4.2.1.24) was purified from rat and rabbit erythrocytes to a homogeneous state. Specific activities were 26.0 and 26.6 units/mg protein for the rat and rabbit enzymes, respectively, and their estimated molecular weight was 280000, each consisting of 8 subunits of Mr 35000. In order to quantitate rat delta-aminolevulinic acid dehydratase at several stages of lead-poisoning, a radioimmunoassay technique using goat antiserum against the rat enzyme was developed for the first time. This technique was specific, reproducible and highly sensitive allowing determination of ng enzyme. When drinking water containing 25 mM lead acetate was given daily to rats ad lib. the delta-aminolevulinic acid dehydratase activity in the blood, assayed without any pretreatment, decreased to 8% of the control level on the next day. On the contrary, the restored enzyme activity, assayed in the presence of Zn2+ and dithiothreitol, was greater than normal by the fourth day of lead administration in bone-marrow cells and by the ninth day in the peripheral blood. The increased activity level stayed the same from the ninth day onward. The enzyme content as determined directly by the radioimmunoassay technique at this stage was about 2-fold above that the control. There was no significant difference in the number of reticulocytes and the distribution profile of different types of reticulocytes between the lead-exposed and non-exposed rats. Therefore, the increase in the amount of delta-aminolevulinic acid dehydratase in erythrocytes of lead-poisoned rats was suggested to be due to an increased rate of synthesis in the bone-marrow cells.


Assuntos
Eritrócitos/enzimologia , Intoxicação por Chumbo/enzimologia , Sintase do Porfobilinogênio/metabolismo , Animais , Medula Óssea/enzimologia , Células da Medula Óssea , Contagem de Eritrócitos , Substâncias Macromoleculares , Peso Molecular , Sintase do Porfobilinogênio/biossíntese , Sintase do Porfobilinogênio/sangue , Coelhos , Ratos , Reticulócitos/citologia
17.
Biochim Biophys Acta ; 1075(1): 75-82, 1991 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-1654110

RESUMO

Phytase (myo-inositol hexakisphosphate phosphohydrolase; EC 3.1.3.8 or 3.1.3.26) was purified from rat intestinal mucosa. The purified enzyme preparation exhibited two protein bands on SDS-polyacrylamide gel electrophoresis with estimated molecular masses of 70 kDa and 90 kDa. Rabbit antisera prepared against the 90K subunit cross-reacted with the 70K subunit on immunoblotting. The peptide maps of the 70K and 90K subunits were similar, and the N-terminal amino acid sequences of the two subunit proteins were almost identical. Treatments to remove sugar moieties from the proteins showed that the two subunit proteins had different oligosaccharide chains, although the difference in their molecular masses was not due to the difference in their oligosaccharide compositions. The purified enzyme also showed activity of alkaline phosphatase (orthophosphoric monoester phosphohydrolase; EC 3.1.3.1), but the properties of the two enzyme activities were different; the optimum pH for phytase activity was 7.5, while that for alkaline phosphatase was 10.4. Phytase activity did not necessarily require divalent cations, while Mg2+ was essential for alkaline phosphatase activity. Phenylalanine, a specific inhibitor of intestine-type alkaline phosphatase had no effect on the phytase activity.


Assuntos
6-Fitase/isolamento & purificação , Mucosa Intestinal/enzimologia , 6-Fitase/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Eletroforese em Gel de Poliacrilamida , Glicosilação , Concentração de Íons de Hidrogênio , Masculino , Dados de Sequência Molecular , Peso Molecular , Mapeamento de Peptídeos , Ratos , Ratos Endogâmicos , Zinco/química
18.
J Mol Biol ; 203(2): 281-98, 1988 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-2462054

RESUMO

We have determined the complete nucleotide sequence of chloroplast DNA from a liverwort, Marchantia polymorpha, using a clone bank of chloroplast DNA fragments. The circular genome consists of 121,024 base-pairs and includes two large inverted repeats (IRA and IRB, each 10,058 base-pairs), a large single-copy region (LSC, 81,095 base-pairs), and a small single-copy region (SSC, 19,813 base-pairs). The nucleotide sequence was analysed with a computer to deduce the entire gene organization, assuming the universal genetic code and the presence of introns in the coding sequences. We detected 136 possible genes. 103 gene products of which are related to known stable RNA or protein molecules. Stable RNA genes for four species of ribosomal RNA and 32 species of tRNA were located, although one of the tRNA genes may be defective. Twenty genes encoding polypeptides involved in photosynthesis and electron transport were identified by comparison with known chloroplast genes. Twenty-five open reading frames (ORFs) show structural similarities to Escherichia coli RNA polymerase subunits, 19 ribosomal proteins and two related proteins. Seven ORFs are comparable with human mitochondrial NADH dehydrogenase genes. A computer-aided homology search predicted possible chloroplast homologues of bacterial proteins; two ORFs for bacterial 4Fe-4S-type ferredoxin, two for distinct subunits of a protein-dependent transport system, one ORF for a component of nitrogenase, and one for an antenna protein of a light-harvesting complex. The other 33 ORFs, consisting of 29 to 2136 codons, remain to be identified, but some of them seem to be conserved in evolution. Detailed information on gene identification is presented in the accompanying papers. We postulated that there were 22 introns in 20 genes (8 tRNA genes and 12 ORFs), which may be classified into the groups I and II found in fungal mitochondrial genes. The structural gene for ribosomal protein S12 is trans-split on the opposite DNA strand. The universal genetic code was confirmed by the substitution pattern of simultaneous codons, and by possible codon recognition of the chloroplast-encoded tRNA molecules, assuming no importation of tRNA molecules from the cytoplasm. The nucleotide residue A or T is preferred at the third position of the codons (G+C, 11.9%) and in intergenic spacers (G+C, 19.5%), resulting in an overall G+C content that is low (28.8%) throughout the liverwort chloroplast genome. Possible gene expression signals such as promoters and terminators for transcription, predicted locations of gene products, and DNA replicative origins are discussed.


Assuntos
Cloroplastos , DNA/genética , Plantas/genética , Sequência de Bases , Células Cultivadas , Mapeamento Cromossômico , Clonagem Molecular , Genes , Dados de Sequência Molecular , RNA/genética , Proteínas Ribossômicas/genética
19.
J Insect Physiol ; 51(12): 1366-75, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16226273

RESUMO

Lutzomyia longipalpis adult males form leks on or near hosts and release (1S,3S,7R)-3-methyl-alpha-himachalene from their tergal glands to lure females to the same site for mating and feeding. Here we have examined whether the male-produced attractant could also serve as a male aggregation stimulus. High resolution chiral capillary gas chromatography analysis of male tergal gland extracts, synthetic (1S,3S,7R)-3-methyl-alpha-himachalene, and a synthetic mixture of all isomers of 3-methyl-alpha-himachalene, was coupled to electrophysiological recordings from ascoid sensillum receptor cells in antennae of male and female sandflies. Receptor cells of both sexes responded only to the main component of the male tergal gland extract that eluted at the same retention time as (1S,3S,7R)-3-methyl-alpha-himachalene. Furthermore, of the eight 3-methyl-alpha-himachalene isomers in the synthetic mixture only the fraction containing (1S,3S,7R)-3-methyl-alpha-himachalene, co-eluting with an isomer of (1S*,3S*,7S*)-3-methyl-alpha-himachalene, elicited an electrophysiological response from male and female ascoid sensillum receptor cells. Both males and females flew upwind in a wind tunnel towards a filter paper disk treated with either 4-6 male equivalents of the tergal gland extract, pure (1S,3S,7R)-3-methyl-alpha-himachalene or the synthetic mixture of eight isomers. This indicates that (1S,3S,7R)-3-methyl-alpha-himachalene derived from L. longipalpis males may have a dual function in causing male aggregation as well as serving as a sex pheromone for females.


Assuntos
Atividade Motora/efeitos dos fármacos , Psychodidae/química , Células Receptoras Sensoriais/efeitos dos fármacos , Sesquiterpenos/química , Atrativos Sexuais/química , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Brasil , Cromatografia Gasosa , Misturas Complexas , Eletrofisiologia , Masculino , Psychodidae/efeitos dos fármacos , Sesquiterpenos/farmacologia , Atrativos Sexuais/farmacologia
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