Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 244
Filtrar
1.
Cell Mol Life Sci ; 77(21): 4223-4236, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32367192

RESUMO

The determination of sex is an important hallmark in the life cycle of organisms, in which the fate of gonads and then the individual sex are defined. In gonochoristic teleost fish, this process is characterized by a high plasticity, considering that in spite of genotypic sex many environmental factors can cause shifts from one to another molecular pathway, resulting in organisms with mismatching genotypic and phenotypic sexes. Interestingly, in most instances, both female-to-male or male-to-female sex-reversed individuals develop functional gonads with normal gametogenesis and respective progenies with full viability. The study of these mechanisms is being spread to other non-model species or to those inhabiting more extreme environmental conditions. Although water temperature is an important mechanism involved in sex determination, there are other environmental stressors affected by the climate change which are also implicated in stress response-induced masculinization in fish. In this regard, the brain has emerged as the transducer of the environment input that can influence the gonadal fate. Furthermore, the evaluation of other environmental stressors or their synergic effect on sex determination at conditions that simulate the natural environments is growing gradually. Within such scope, the concerns related to climate change impacts rely on the fact that many of biotic and abiotic parameters reported to affect sex ratios are expected to increase concomitantly as a result of increased greenhouse gas emissions and, particularly worrying, many of them are related to male bias in the populations, such as high temperature, hypoxia, and acidity. These environmental changes can also generate epigenetic changes in sex-related genes affecting their expression, with implications on sex differentiation not only of exposed individuals but also in following generations. The co-analysis of multi-stressors with potential inter- and transgenerational effects is essential to allow researchers to perform long-term predictions on climate change impacts in wild populations and for establishing highly accurate monitoring tools and suitable mitigation strategies.


Assuntos
Peixes/fisiologia , Processos de Determinação Sexual , Animais , Mudança Climática , Meio Ambiente , Epigênese Genética , Feminino , Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Diferenciação Sexual , Estresse Fisiológico
2.
J Clin Pharm Ther ; 37(1): 49-52, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21332567

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Renal impairment is unavoidable after laparoscopic radical nephrectomy (LRN) and is an important consideration for drug therapy. It is possible that the renal impairment after LRN causes adverse reactions following reduced elimination of some renally excreted drugs, such as hypoglycaemic drugs. However, there are few studies of renal function in patients with diabetes mellitus (DM) in the first week after LRN. The purpose of this study was to examine whether renal impairment after LRN affected glycaemic control. We assessed pre- and postoperative renal function of DM patients and examined whether re-administration of hypoglycaemic drugs in the first week after LRN causes episodes of hypoglycaemia. METHODS: Renal carcinoma patients undergoing LRN in Nagoya University Hospital from January 2007 to December 2009 were identified in a retrospective cohort study design. Patients were divided into non-DM (n = 60) and DM (n = 14) groups. RESULTS AND DISCUSSION: There were significant differences in postoperative estimated glomerular filtration rate values between the non-DM and DM groups. Four of nine patients (44%) experienced hypoglycaemia induced by re-administration of hypoglycaemic drugs, namely, sulfonylureas. WHAT IS NEW AND CONCLUSION: In the present study, we found the first evidence that renal impairment in the first week after LRN was a risk factor of hypoglycaemia. To prevent hypoglycaemia after LRN, assessment of renal function and the use of insulin therapy are important.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemia/etiologia , Hipoglicemiantes/farmacologia , Nefrectomia/efeitos adversos , Idoso , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Hospitais Universitários , Humanos , Hipoglicemiantes/farmacocinética , Neoplasias Renais/cirurgia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Nefrectomia/métodos , Insuficiência Renal/complicações , Estudos Retrospectivos , Fatores de Risco , Compostos de Sulfonilureia/farmacocinética , Compostos de Sulfonilureia/farmacologia
3.
Anim Genet ; 41(1): 81-4, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19754851

RESUMO

The Patagonian pejerrey Odontesthes hatcheri is an atherinopsid species presenting genotypic sex determination (GSD) at intermediate temperatures and temperature-dependent sex determination at the low and high ranges of thermal tolerance. A recent study revealed the presence of a sex-linked SNP marker in some males of this species, but a strain which inherits the marker faithfully has not been established. This research was conducted to develop such a strain, for use as a tool to study the molecular mechanisms of gonadal sex differentiation and sexual dimorphism, and to obtain basic information on the GSD mode in this species. For these purposes, we performed backcrosses and full-sibling crosses using males and females whose presumptive genotypic sex was inferred from the presence of the sex-linked SNP marker. Four backcrosses between SNP(-) daughters and their SNP(+) father generated balanced sex ratios with the phenotypic sex matching the genotypic sex in most cases (98.21%) at an intermediate, sexually neutral temperature (21 degrees C). Full-sibling crosses between these four SNP(-) females and their SNP(+) brothers produced three progenies with balanced sex ratios and one with 94.4% males. The results of this study confirm that a strain inheriting the sex-linked SNP marker was successfully developed. Moreover, the inheritance pattern of the marker and the sex ratios of the progenies provide strong evidence that the GSD mode in O. hatcheri is the XX-XY system.


Assuntos
Processos de Determinação Sexual , Smegmamorpha/genética , Animais , Cruzamentos Genéticos , Feminino , Masculino , Polimorfismo de Nucleotídeo Único , Temperatura
4.
Transplant Proc ; 41(1): 437-40, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19249575

RESUMO

Pyoderma gangrenosum (PG), a rare skin disease of unknown etiology, forms intractable skin ulcers at surgical or traumatic sites. This case is a 40-year-old woman with PG who experienced end-stage renal disease due to type 1 diabetes mellitus. Arteriovenous fistula (AVF) creation and peritoneal dialysis introduction were considered to be difficult, because this patient had a history of developing intractable aseptic ulcers at surgical sites. Therefore, she continued hemodialysis via a temporary catheter. With frequent catheter exchange, there was stenosis of both the femoral veins and the internal jugular vein. Therefore, a hemodialysis catheter that could be used for the long term was inserted into the left jugular vein as a final site. To prevent the patient not being able to continue hemodialysis, we performed a kidney transplantation to save her life. We performed a blood type-compatible, living donor kidney transplantation after confirming the absence of active skin lesions. The 69-year-old donor was her mother. Induction immunotherapy started with tacrolimus, mycophenolate mofetil, steroids, and basiliximab. Intravenous pulses of methylprednisolone were performed to prevent ulceration of the surgical site on days 0-2 (500 mg/d). The postoperative course was excellent. After the operation, ulceration of the surgical site was never observed. The serum creatinine value was 0.87 mg/dL at 6 months. To our knowledge, renal transplantations for a patient with PG has not been previously reported.


Assuntos
Transplante de Rim/fisiologia , Pioderma Gangrenoso/cirurgia , Adulto , Idoso , Creatinina/sangue , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Doadores Vivos , Masculino , Mães , Pioderma Gangrenoso/terapia , Diálise Renal , Resultado do Tratamento
5.
Theriogenology ; 71(7): 1162-72, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19168208

RESUMO

Germ cell (GC) transplantation (GCT) is a novel reproductive technology with application in seed production and conservation of endangered species. This study examined the suitability of treatment with Busulfan, a cytotoxic agent, and warm water, known to cause GC degeneration, for depletion of endogenous GCs in sub-adult Patagonia pejerrey Odontesthes hatcheri intended as hosts in GCT. In two experiments, fish were treated with six combinations of temperature (intermediate and high, 20 and 25 degrees C, respectively) and Busulfan (0, 20, and 40 mg/kg body weight), given intraperitoneally (ip) as a single (0 week) or repeated (0 and 4 week) dose. The effectiveness of the treatments was assessed by gonado-somatic index, histology, and (germ cell-specific) vasa gene expression after 8 weeks. Fish were allowed to recover at 17 degrees C for 4-8 weeks after the treatments to ascertain the permanency of the effects. The high temperature (25 degrees C) alone induced only incipient gonadal degeneration and germ cell loss, but was highly effective in combination with double administration of 40 mg/kg Busulfan. Males tolerated Busulfan better and were more easily depleted of germ cells than females. Animals treated for 8 weeks were severely devoid of germ cells, but were still capable of gametogenesis. Thus, the combination of Busulfan and high water temperature appeared to be efficient for depletion of GCs in adult fish; and the treated gonads retained the ability to support GC proliferation and differentiation. Furthermore, quantitative analysis of vasa transcript levels was found to be an useful to monitor the degree of gonad sterility during treatment.


Assuntos
Alquilantes/farmacologia , Bussulfano/farmacologia , Células Germinativas/efeitos dos fármacos , Smegmamorpha/fisiologia , Alquilantes/administração & dosagem , Animais , Bussulfano/administração & dosagem , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Temperatura Alta , Masculino , RNA Helicases/genética , RNA Helicases/metabolismo , Caracteres Sexuais , Maturidade Sexual , Testículo/efeitos dos fármacos
6.
Clin Nephrol ; 70(3): 203-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18793561

RESUMO

BACKGROUND: This study was made to present our experience and results with transperitoneal laparoscopic-assisted renal biopsy (LARB) in Nagoya University Hospital as a good alternative for open renal biopsy. METHODS: 21 patients (14 male, 7 female, mean age 58 years, range 21-83 years) were unsuitable for percutaneous renal biopsy. Therefore, they underwent laparoscopic-assisted renal biopsy. The kidney was approached transperitoneally via three ports, cortical tissue was obtained using a 16-gauge gun-mounted semiautomatic biopsy needle. Hemostasis was obtained by applying pressure on the renal puncture using gauze until bleeding had been stopped (range 5-20 min). RESULTS: Adequate cortical tissue and accurate diagnoses were obtained in all patients. Mean operative time was 83 min (range 65-120 min) and mean estimated blood loss was 5.5 ml (range 1-10 ml). There were no intraoperative complications: no open conversion, blood transfusions or gross hematuria. All patients walked about freely and could tolerate regular food on the first postoperative day. The only postoperative complication was a hernia formation at the place of trocar insertion 3 months after the operation in one patient who previously underwent multiple surgery for 3 arterial grafts and appendicitis. CONCLUSIONS: LARB is a safe and accurate procedure for obtaining cortical biopsies with minimal blood loss. Although LARB remains a surgical procedure which requires general anesthesia, LARB to date may be considered as a good alternative to open renal biopsy for patients in whom a closed percutaneous approach is either a relative or absolute contraindication.


Assuntos
Biópsia/métodos , Rim/patologia , Laparoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/efeitos adversos , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade
7.
Transplant Proc ; 40(7): 2268-70, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18790209

RESUMO

It is known that administration of mycophenolate mofetile (MMF) is associated with BK virus (BKV) nephropathy in renal transplant recipients. To determine any inhibitory effect of mizoribine for BKV, seven patients with positive BKV in their urine who took MMF as immunosuppressive therapy were evaluated after MMF was changed to mizoribine. Baseline BKV DNA in urine, which ranged from 2.2 x 10(2) to 5.5 x 10(6) copies per milliliter, decreased in all cases (mean = 1.9 x 10(-1) times; median 2.8 x 10(-3) times). Four cases turned negative within 6 months and one within 12 months. No acute rejection or deterioration of graft function occurred during the administration of mizoribine. An inhibitory effect of mizoribine on BKV was suggested.


Assuntos
Vírus BK , DNA Viral/urina , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Ácido Micofenólico/análogos & derivados , Infecções por Polyomavirus/diagnóstico , Ribonucleosídeos/uso terapêutico , Adulto , Quimioterapia Combinada , Humanos , Transplante de Rim/efeitos adversos , Pessoa de Meia-Idade , Ácido Micofenólico/efeitos adversos
8.
J Clin Invest ; 86(6): 1885-91, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2174909

RESUMO

Prostacyclin (PGI2) has been reported to stimulate activities of acid cholesteryl ester hydrolase (ACEH; EC 3.1.1.13) and neutral cholesteryl ester hydrolase (NCEH; EC 3.1.1.13) in the smooth muscle cells leading to a decrease in intracellular cholesteryl ester. Recently, we have found that the half-life of PGI2 was prolonged through stabilization by HDL. HDL is known to have anti-atherogenic properties, although its precise mechanism has not been fully clarified. We therefore hypothesized that HDL can exert anti-atherogenic action by augmenting PGI2-stimulated increases in the activities of ACEH and NCEH. After incubation with PGI2 and HDL, a cell homogenate was made from which the activities of ACEH and NCEH were assessed. HDL significantly augmented the PGI2-induced increase in the activities of both enzymes. This effect of HDL was abolished in the absence of PGI2. Elevated intracellular levels of cyclic AMP were maintained for longer periods by HDL. The increase in both intracellular cyclic AMP levels and enzyme activities disappeared in the presence of an inhibitor of adenylate cyclase, 2'5'-dideoxyadenosine. Radiolabeled smooth muscle cells demonstrated a significant loss in total cholesterol and cholesteryl ester after treatment with PGI2 and HDL, due to the increase in cholesteryl ester hydrolytic activities. These data suggest that HDL enhanced the PGI2-stimulated hydrolysis of cholesteryl ester and augmented the PGI2-induced reduction of cellular cholesteryl ester content by stabilizing PGI2.


Assuntos
Ésteres do Colesterol/metabolismo , Epoprostenol/metabolismo , Epoprostenol/farmacologia , Lipoproteínas HDL/farmacologia , Animais , Bovinos , Células Cultivadas , Colesterol/metabolismo , AMP Cíclico/fisiologia , Relação Dose-Resposta a Droga , Técnicas In Vitro , Lipoproteínas LDL/farmacologia , Lipoproteínas VLDL/metabolismo , Músculo Liso/metabolismo , Esterol Esterase/metabolismo
9.
Circulation ; 102(19 Suppl 3): III269-74, 2000 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-11082400

RESUMO

BACKGROUND: The molecular mechanism of neointimal hyperplasia after vein graft surgery remains elusive. Vacuolar H(+)-ATPase (V-ATPase) is involved in intracellular trafficking and may play a crucial role in neointimal cell growth. METHODS AND RESULTS: Cultured human saphenous vein segments developed neointimal formation within 10 days. Neointimal cells were positive for vimentin and alpha-smooth muscle actin but negative for desmin, which is indicative of myofibroblasts. Those myofibroblasts were found to have originated from periadventitial fibroblasts, which upregulated the expression of 16-kDa proteolipid of V-ATPase before proliferation and phenotypic modulation. Neointimal myofibroblast growth and survival were highly sensitive to inhibition of V-ATPase by bafilomycin A(1) (BA(1)), because the incorporation of [(3)H]thymidine into the myofibroblasts was significantly inhibited by nanomolar concentrations of BA(1) and apoptotic cell death was induced by a similar concentration range of BA(1). In contrast, endothelial cells and differentiated smooth muscle cells were resistant to apoptosis by BA(1). CONCLUSIONS: These results suggest that V-ATPase plays a crucial role in growth and phenotypic modulation of myofibroblasts that contributes to neointimal formation in cultured human saphenous vein.


Assuntos
Fibroblastos/enzimologia , Macrolídeos , Músculo Liso Vascular/enzimologia , ATPases Translocadoras de Prótons/metabolismo , Veia Safena/enzimologia , Túnica Íntima/metabolismo , ATPases Vacuolares Próton-Translocadoras , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antígenos de Diferenciação/biossíntese , Apoptose/efeitos dos fármacos , Bromodesoxiuridina , Divisão Celular/efeitos dos fármacos , Movimento Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Fenótipo , Subunidades Proteicas , Proteolipídeos/biossíntese , Veia Safena/citologia , Timidina/metabolismo , Túnica Íntima/citologia
10.
Circulation ; 101(10): 1102-8, 2000 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-10715255

RESUMO

BACKGROUND: Enhanced coronary vasomotion may contribute to acute coronary occlusion during the acute phase of myocardial infarction (AMI). Japanese have a higher incidence of variant angina than Caucasian patients, but racial differences in vasomotor reactivity early after AMI are controversial. METHODS AND RESULTS: The same team studied 15 Japanese and 19 Caucasian patients within 14 days of AMI by acetylcholine injection into non-infarct-related (NIRA) and infarct-related (IRA) coronary arteries followed by nitroglycerin. Incidence of vasodilation, vasoconstriction, spasm, and basal tone were assessed in proximal, middle, and distal segments after each drug bolus by quantitative angiography. Japanese patients had much lower cholesterol levels than Caucasians (183+/-59 versus 247+/-53 mg/dL, P<0.006) but showed a lower incidence of vasodilation (2% versus 9% of coronary segments) and a greater incidence of spasm after acetylcholine (47% versus 15% of arteries, P<0.00001). Incidence of spasm was higher in IRAs than in NIRAs in both populations (67% versus 39% and 23% versus 11%, respectively). Multivessel spasm was more common (64% versus 17%, P<0.02) and vasoconstriction of nonspastic segments was greater in Japanese patients (-23.4+/-14.9% versus -20.1+/-15.7%, P<0.02) in the presence of similar average basal coronary tone with respect to post-nitroglycerin dilation and of nonsignificant differences of coronary atherosclerotic score. CONCLUSIONS: Soon after AMI, Japanese patients exhibited a 3-fold-greater incidence of spasm and greater vasoconstriction of nonspastic segments after acetylcholine than Caucasians. The causes of such differences warrant further investigation because they may have relevant pathophysiological and therapeutic implications.


Assuntos
Povo Asiático , Vasoespasmo Coronário/etnologia , Infarto do Miocárdio/etnologia , População Branca , Acetilcolina/administração & dosagem , Idoso , Angiografia , Arteriosclerose/epidemiologia , Arteriosclerose/etiologia , Vasoespasmo Coronário/epidemiologia , Vasoespasmo Coronário/etiologia , Feminino , Humanos , Incidência , Itália/epidemiologia , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Vasoconstrição , Sistema Vasomotor/fisiopatologia
11.
J Am Coll Cardiol ; 7(1): 25-9, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3941213

RESUMO

To investigate whether thromboxane A2 is responsible for the initiation of vasospastic angina pectoris, thromboxane B2 levels were measured in the great cardiac vein and the arterial blood of 12 patients with clinically and angiographically proved vasospastic angina and therapeutic trials were performed with selective thromboxane A2 synthetase inhibitor OKY-046, an imidazole derivative. During ergonovine-provoked (11 cases) and spontaneous (1 case) anginal attacks, great cardiac vein thromboxane B2 increased from 121 +/- 27 to 430 +/- 382 pg/ml (p less than 0.05, n = 12), arterial thromboxane B2 increased from 93 +/- 18 to 122 +/- 33 pg/ml (NS, n = 12) and thromboxane B2 production increased from 3.18 +/- 1.88 to 25.16 +/- 22.32 ng/min (p less than 0.05, n = 6). Subsequently, OKY-046, 400 mg/day orally, was administered to 7 of the 12 patients, while a continuous electrocardiogram was recorded on a dual channel Holter monitor during a 3 day placebo period and the 3 day OKY-046 regimen. Although peripheral plasma thromboxane B2 levels decreased significantly from 98 +/- 15 to 12 +/- 8 and 28 +/- 10 pg/ml (1 and 6 hours after ingestion, respectively) (p less than 0.05 for both), 6-keto-prostaglandin F1 alpha production in serum increased significantly from 0.48 +/- 0.22 to 2.3 +/- 0.72 (1 hour) and 1.8 +/- 0.46 ng/ml (6 hours) (p less than 0.05 for both) during OKY-046 administration.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Acrilatos/farmacologia , Angina Pectoris Variante/enzimologia , Metacrilatos/farmacologia , Tromboxano B2/sangue , Tromboxano-A Sintase/antagonistas & inibidores , Administração Oral , Adulto , Idoso , Angina Pectoris Variante/sangue , Angina Pectoris Variante/tratamento farmacológico , Aorta/metabolismo , Cateterismo Cardíaco , Vasos Coronários/metabolismo , Eletrocardiografia , Humanos , Masculino , Metacrilatos/administração & dosagem , Pessoa de Meia-Idade
12.
J Am Coll Cardiol ; 5(6): 1283-91, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3998312

RESUMO

Myocardial metabolism was assessed in 20 patients with acute anterior myocardial infarction using lactate uptake (defined as (aortic lactate - great cardiac venous lactate)/aortic lactate X 100) as an index. The regional ejection fraction of the anterior wall was obtained from left ventriculography. There was a linear relation between lactate uptake and regional ejection fraction (r = 0.79, p less than 0.001). Four patients without total occlusion in the infarct vessel had a higher lactate uptake (19.6 +/- 6.7 versus 4.2 +/- 13.4%, p less than 0.05) and regional ejection fraction (26.3 +/- 7.9 versus 14.9 +/- 7.0%, p less than 0.05) than did 16 patients with total occlusion. The latter group of patients underwent intracoronary infusion of urokinase, which resulted in reperfusion in 13 patients. Lactate uptake before urokinase infusion (sample I), just after reperfusion (sample II), 30 minutes after reperfusion (sample III) and 4 weeks after reperfusion (sample IV) was 5.7 +/- 13.2, -13.9 +/- 14.7, 2.9 +/- 15.2 and 20.2 +/- 11.0%, respectively (sample I versus II and II versus III, p less than 0.01; sample I versus IV and III versus IV, p less than 0.05). The decrease in lactate uptake immediately after reperfusion, which was accompanied by an increase in creatine kinase-MB isoenzyme release into the blood, was considered to be the result of a "washout" effect. Lactate uptake was ameliorated 4 weeks later, accompanied by an improvement (from 15.1 +/- 7.1 to 23.4 +/- 7.2%, p less than 0.01) in the regional ejection fraction. It is concluded that the degree of asynergy was closely related to the extent of metabolic deterioration in myocardial infarction.


Assuntos
Ventrículos do Coração/fisiopatologia , Lactatos/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Doença Aguda , Adulto , Idoso , Circulação Colateral , Angiografia Coronária , Circulação Coronária , Vasos Coronários/fisiopatologia , Creatina Quinase/sangue , Feminino , Humanos , Isoenzimas , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Volume Sistólico , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem
13.
J Leukoc Biol ; 57(1): 36-44, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7530282

RESUMO

An antirat monoclonal antibody (mAb) against inducible nitric oxide synthase (iNOS), ANOS11, was used for immunohistochemistry to examine the expression of iNOS in various organs and tissues of adult rats in experimental endotoxic shock induced by lipopolysaccharide (LPS) injection. The phenotype of iNOS-expressed cells was also examined immunohistochemically using various mAbs. In control rats, very few cells were positive for ANOS11 except in the thymus. After intravenous injection of LPS, the number of iNOS-positive cells increased rapidly in almost all organs, except the thymus and brain, peaked 6 h after the injection, and decreased slowly. Of the numerous inflammatory cells that infiltrated the lungs, liver, and spleen after LPS injection, many were positive for ANOS11. Besides inflammatory cells, hepatocytes and endothelial cells of the aorta were also positive for ANOS11 but only around 6 h after injection. The cellular composition of iNOS-positive infiltrated cells changed along with the progression of endotoxic shock. At 4 to 6 h after injection, most iNOS-positive cells were considered polymorphonuclear leukocytes judging by their positive reactivity to OX42 and their nuclear morphology. The population of iNOS-positive macrophages positive for ED1 or ED2 increased with time. After 24 h, many iNOS-positive macrophages were found around the focal necrosis in the liver and spleen. These results indicate that the expression of iNOS in neutrophils, endothelial cells, and hepatocytes precedes that of macrophages in experimental endotoxic shock. The expression of iNOS in various cells and organs is closely associated with the progress and pathological changes of endotoxic shock.


Assuntos
Aminoácido Oxirredutases/análise , Aminoácido Oxirredutases/imunologia , Anticorpos Monoclonais/imunologia , Choque Séptico/enzimologia , Aminoácido Oxirredutases/fisiologia , Animais , Endotélio/enzimologia , Endotélio/patologia , Endotélio/ultraestrutura , Immunoblotting , Imuno-Histoquímica , Lipopolissacarídeos , Fígado/enzimologia , Fígado/patologia , Fígado/ultraestrutura , Pulmão/citologia , Pulmão/enzimologia , Pulmão/ultraestrutura , Masculino , Microscopia Imunoeletrônica , Neutrófilos/enzimologia , Neutrófilos/patologia , Neutrófilos/ultraestrutura , Óxido Nítrico Sintase , Ratos , Ratos Wistar , Choque Séptico/induzido quimicamente , Choque Séptico/patologia , Organismos Livres de Patógenos Específicos , Baço/embriologia , Baço/patologia , Baço/ultraestrutura
14.
Cardiovasc Res ; 21(2): 119-23, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3664541

RESUMO

Diffuse coronary artery vasoconstriction was provoked in the rabbit by a stable thromboxane A2 analogue, STA2 (9,11-epithio-11,12-methano thromboxane A2). Injection of 25 micrograms.kg-1 STA2 into the left main trunk caused complete occlusion of the left anterior descending artery and narrowing of the left circumflex artery. Two minutes after injection, however, the diameter of the coronary artery returned to the control value (n = 10). The right coronary artery was also temporarily occluded by an injection of 25 micrograms.kg-1 STA2. Left ventricular end diastolic pressure increased significantly, and ST segment elevation of the electrocardiogram occurred during vasoconstriction. The angiographic findings showed that the vasoconstriction in the coronary artery induced by STA2 was similar to the diffuse vasoconstriction seen clinically. Induction of the vasoconstriction by STA2 was prevented by the preadministration of 25 micrograms.kg-1 of either a calcium antagonist, diltiazem, or a thromboxane A2 receptor antagonist, ONO 3708 (n = 10). The relation of the calcium movement to this vasoconstriction was studied in vitro using the isolated left circumflex artery in the rabbit. STA2 (50 micrograms.litre-1 to 0.5 mg.litre-1) produced a concentration dependent contraction of helical strips of left circumflex artery. Diltiazem (50-100 g.litre-1) suppressed this contraction dose dependently. ONO 3708 (10 micrograms.litre-1 to 1 mg.litre-1) caused a significant rightward and downward shift of the dose-response curve.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Vasoespasmo Coronário/induzido quimicamente , Tromboxano A2/análogos & derivados , Animais , Cálcio/farmacologia , Angiografia Coronária , Vasoespasmo Coronário/diagnóstico por imagem , Diltiazem/farmacologia , Relação Dose-Resposta a Droga , Coelhos , Tromboxano A2/antagonistas & inibidores , Tromboxano A2/toxicidade
15.
Antioxid Redox Signal ; 3(3): 403-13, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11491653

RESUMO

Reperfusion of ischemic myocardium results in apoptotic cell death, which can be blocked by adapting the heart to ischemic stress induced by cyclic episodes of brief periods of ischemia and reperfusion. In concert, the antiapoptotic gene bcl-2 is decreased by ischemia/reperfusion, but increased in the ischemically adapted myocardium. To examine if bcl-2 plays a crucial role in cardioprotection, adaptive cardioprotection was further examined in the hearts treated with antisense bcl-2 oligodeoxynucleotides (ODN). Isolated Langendorff-perfused rat hearts were divided into three groups: control (perfused with Krebs-Henseleit bicarbonate buffer for 210 min); 30-min ischemia followed by 2-h reperfusion; ischemic adaptation followed by 30-min ischemia and 2-h reperfusion. The last (adapted heart) group was subdivided into another two groups: one was transfected 48 h earlier with antisense bcl-2 ODN, whereas the other group was transfected with sense bcl-2 ODN. Cardioprotection was examined by determining cardiomyocyte death due to necrosis and apoptosis. Antisense gene therapy almost completely abolished bcl-2 protein expression in the hearts. Bcl-2 mRNA was down-regulated in the ischemic/reperfused heart, but up-regulated in the adapted myocardium. Adapted myocardium showed decreased infarct size and reduced number of apoptotic cardiomyocytes. Ischemia/reperfusion resulted in increased oxidative stress as evidenced by increased malonaldehyde formation. Adapted myocardium had a reduced amount of malonaldehyde. Antisense bcl-2 ODN completely abolished the cardioprotective effects of adaptation by eliminating the antideath signal of bcl-2. In concert, reduced oxidative stress in the adapted myocardium no longer persisted. The results suggest an antioxidant role of bcl-2 that appeared to be essential for the cardioprotection achieved by ischemic adaptation.


Assuntos
Apoptose , Terapia Genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Adaptação Fisiológica , Animais , Antioxidantes/metabolismo , Western Blotting , Masculino , Malondialdeído/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Técnicas de Cultura de Órgãos , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/análise , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Transfecção
16.
Antioxid Redox Signal ; 3(1): 103-12, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11291590

RESUMO

Coenzyme Q10 (CoQ) has long been utilized as a cardioprotective agent in various heart diseases. One of the most important mechanisms by which CoQ exerts cardioprotection is aerobic ATP production as a mobile electron carrier in the mitochondrial electron transfer chain. The ability of CoQ to afford myocardial protection is also attributed to its antioxidant property. However, CoQ may also act as a pro-oxidant through the generation of reactive oxygen species. Although excess oxidative stress is known to induce death signaling via cytochrome c release from mitochondria, it is now apparent that a brief exposure to oxidative stress stimulates redox signaling for acquisition of tolerance to oxidative stress. Therefore, we have investigated dual involvement of CoQ in redox signaling generation through enhanced production of reactive oxygen species and death signaling inhibition through antioxidation. Mitochondria were isolated from the rat heart and incubated with CoQ (10 or 100 microM) or its vehicle HCO 60 for 1 h. H2O2 and cytochrome c release from respiring mitochondria were increased by antimycin A (2 microM), an inhibitor of complex III respiratory chain, or by high Ca2+ (10 microM). This enhanced release of H2O2 was associated with an increase in lipid peroxidation as measured with 4-hydroxy-2-nonenal-modified proteins and with large amplitude swelling of mitochondria. CoQ potentiated H2O2 release from antimycin A- or high Ca(2+)-treated mitochondria, but was capable of inhibiting lipid peroxidation and large amplitude swelling, and attenuated cytochrome c release from the mitochondria. In addition, CoQ increased ATP synthesis by mitochondria. These results suggest that CoQ plays dual roles in mitochondrial generation of intracellular signaling. CoQ acts as a pro-oxidant that participates in redox signaling. CoQ also acts as an antioxidant that inhibits permeability transition and cytochrome c release, and increases ATP synthesis, thereby attenuating death signaling toward apoptosis and necrosis.


Assuntos
Mitocôndrias Cardíacas/efeitos dos fármacos , Transdução de Sinais , Ubiquinona/farmacologia , Trifosfato de Adenosina/biossíntese , Animais , Antimicina A/farmacologia , Western Blotting , Cálcio/farmacologia , Morte Celular , Coenzimas , Grupo dos Citocromos c/metabolismo , Citoproteção , Complexo III da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias Cardíacas/metabolismo , Dilatação Mitocondrial , Oxirredução , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Ubiquinona/análogos & derivados
17.
Transplantation ; 72(8): 1376-80, 2001 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11685106

RESUMO

BACKGROUND: The severe shortage of cadaver donor kidneys for transplantation has prompted many centers to utilize older donor kidneys, which have been associated with lower graft survival rates. The aim of the present study was to examine the availability and feasibility of considering kidneys from donors over the age of 60. METHOD: We studied 252 cadaveric renal transplant recipients (156 males, 96 females) who received kidneys from uncontrolled non-heart-beating donors between 1987 and 1997. We performed in situ cooling with especially designed double-balloon catheters to minimize warm ischemic kidney damage. Recipients were classified according to donor age (age 60), and we examined graft survival rates. All patients were followed for a minimum of 1 year after transplantation. RESULTS: Graft survival rates for recipients of kidneys from the older donor group at 1, 5, and 10 years after transplantation were 77%, 37%, and 30%, respectively. Corresponding values for the younger donor kidney recipients were 87%, 64%, and 47%, respectively (P=0.0011). Improved survival rates were noted when older kidneys were used for lighter weight recipients (<54 kg). No other significant factors impacted on older donor graft survival rates. CONCLUSION: Older donor kidneys are associated with poorer graft survival rates. However, kidney transplants from older donors can be quite effective in lighter weight recipients (<54 kg).


Assuntos
Transplante de Rim , Doadores de Tecidos , Adulto , Fatores Etários , Idoso , Cadáver , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade
18.
Am J Cardiol ; 58(10): 1042-5, 1986 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-3535472

RESUMO

A new stable prostacyclin analog, OP-41483, was used in patients with severe congestive heart failure (CHF) due to coronary artery disease and compared with nitroprusside. During infusion of both drugs, mean brachial arterial pressure, total pulmonary resistance, pulmonary artery wedge pressure and systemic vascular resistance decreased significantly. Cardiac index and stroke index also increased significantly. Platelet aggregation did not change significantly during nitroprusside but decreased significantly with OP-41483 infusion. Thus, this analog may be useful for treatment of patients with CHF due to coronary artery disease.


Assuntos
Doença das Coronárias/complicações , Epoprostenol/uso terapêutico , Ferricianetos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Nitroprussiato/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Prostaglandinas Sintéticas/uso terapêutico , Idoso , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
19.
Am J Cardiol ; 61(15): 1181-6, 1988 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2837074

RESUMO

To examine the significance of technetium-99m pyrophosphate/thallium-201 scintigraphic overlap as an indicator of identifying early coronary reperfusion (less than or equal to 3 hours), 32 patients, in whom coronary recanalization was attempted for acute myocardial infarction (AMI), underwent myocardial imaging 3 days after the onset of AMI. The imaging was performed by simultaneous dual emission computed tomography, which allows simultaneous recording of technetium-99m pyrophosphate and thallium-201 images and comparison between both images in the same slice. The patients were separated into 3 groups: 9 patients in whom reperfusion was successful and showed scintigraphic overlap (group A), 12 with successful recanalization but no overlap (group B) and 11 with neither coronary reflow nor overlap (group C). No patient in whom reperfusion failed showed scintigraphic overlap (p less than 0.05). Groups A and B were comparable in age, infarct vessel, collateral circulation, residual coronary stenosis and cumulative release of creatine kinase-MB isoenzyme. However, compared with group B, group A had a shorter interval between onset of AMi and reflow (2.5 +/- 0.8 vs 4.8 +/- 1.3 hours, p less than 0.001). The presence of scintigraphic overlap identified early coronary reflow with a sensitivity of 80%, specificity of 91%, positive predictive accuracy of 89% and negative predictive accuracy of 83%. Thus, technetium-99m/thallium-201 overlap on dual emission computed tomography can be used as an index of documenting early recanalization and might reflect the presence of salvaged myocardium adjacent to the necrotic tissue.


Assuntos
Difosfatos , Infarto do Miocárdio/diagnóstico por imagem , Tecnécio , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão , Ensaios Enzimáticos Clínicos , Angiografia Coronária , Circulação Coronária , Creatina Quinase/sangue , Estudos de Avaliação como Assunto , Humanos , Infarto do Miocárdio/tratamento farmacológico , Pirofosfato de Tecnécio Tc 99m , Fatores de Tempo
20.
Am J Cardiol ; 60(13): 952-7, 1987 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-2823591

RESUMO

Early appearance of positive findings on a technetium-99m pyrophosphate scan has been shown to be associated with the presence of a reperfused acute myocardial infarction (AMI). Early technetium-99m pyrophosphate imaging was performed by emission computed tomography to evaluate reperfusion and to test the feasibility of estimating infarct size soon after coronary reperfusion based on acute positive tomographic findings. Twenty-seven patients with transmural AMI who were treated with intracoronary urokinase infusion followed by percutaneous transluminal coronary angioplasty underwent pyrophosphate imaging 8.7 +/- 2.1 hours after the onset of AMI. None of the 8 patients in whom reperfusion was unsuccessful had acute positive findings. Of 19 patients in whom reperfusion was successful, 17 had acute positive findings (p less than 0.001). In these 17, tomographic infarct volumes were determined from reconstructed transaxial images. The threshold for areas of increased pyrophosphate uptake within the infarct was set at 60% of peak activity by the computerized edge-detection algorithm. The total number of pixels in all transaxial sections showing increased tracer uptake were added and multiplied by a size factor and 1.05 g/cm3 muscle to determine infarct volume. The correlations of tomographic infarct volumes with peak serum creatine kinase (CK) levels (r = 0.82) and with cumulative release of CK-MB isoenzyme (r = 0.89) were good. Moreover, the time to positive imaging was significantly shorter than that to peak CK level (8.5 +/- 2.3 vs 10.4 +/- 2.2 hours, p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Adulto , Idoso , Creatina Quinase/sangue , Difosfatos , Feminino , Humanos , Isoenzimas/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Perfusão , Tecnécio , Pirofosfato de Tecnécio Tc 99m , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa