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1.
Vet J ; 266: 105571, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33323173

RESUMO

Canine transitional cell carcinoma (cTCC) is the most common malignant tumour in the urinary bladder: it is highly invasive and exhibits metastatic characteristics. Inflammation is also strongly related to cTCC. Epithelial tumours often exhibit a mesenchymal cell phenotype during tumour invasion and metastasis owing to epithelial-mesenchymal transition (EMT), which is often induced in chronic inflammation. The aim of this retrospective study was to investigate the expression of epithelial and mesenchymal cell markers in tumour cells and to evaluate its relationship with prognosis of cTCC. In this study, 29 dogs with cTCC who underwent surgical treatment were enrolled. Clinical parameters were reviewed using medical records. Tissue expression of epithelial and mesenchymal markers was evaluated by immunohistochemical analysis. The association between the expression of mesenchymal cell markers and clinical parameters, including prognosis, was statistically examined. In five normal bladder tissues used as controls, no expression of mesenchymal markers was observed, except for one tissue that expressed fibronectin. Conversely, epithelial tumour cells expressed vimentin and fibronectin in 23/29 and 19/28 cTCC tissues, respectively. Regarding clinical parameters, vimentin score in Miniature Dachshunds was significantly higher than those in other dog breeds (P < 0.001). Multivariate survival analyses revealed that age>12 years was related to shorter progression-free survival (P = 0.02). Higher vimentin score, lower fibronectin score, and advanced clinical T stage were significantly correlated with shorter median survival time (P < 0.05). The results of this study indicate that vimentin expression was associated with cTCC progression. Further studies are needed to examine the incidence and relevance of EMT in cTCC.


Assuntos
Carcinoma de Células de Transição/veterinária , Doenças do Cão/patologia , Transição Epitelial-Mesenquimal , Neoplasias da Bexiga Urinária/veterinária , Fatores Etários , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/metabolismo , Doenças do Cão/metabolismo , Cães , Feminino , Fibronectinas/metabolismo , Imuno-Histoquímica , Masculino , Prognóstico , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/metabolismo , Vimentina/metabolismo
2.
Pharmazie ; 75(11): 554-558, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33239128

RESUMO

A prodrug of levofloxacin (LVFX), cilexetil ester of LVFX (LVFX-CLX), was synthesized to examine whether the prodrug can avoid chelate formation with metal cations in the gastrointestinal tract. LVFX-CLX exhibited a 10-times higher partition coefficient than LVFX. In vitro, LVFX was precipitated by 76.1% in the presence of a 10-times higher concentration of aluminium chloride (Al3+), but LVFX-CLX was not. LVFX-CLX was rapidly hydrolyzed enzymatically by rat plasma, intestinal mucosal and liver homogenates at 37 °C, but not by pancreatic enzymes and luminal fluid. The minimum inhibitory concentration values of LVFX-CLX against S. aureus, E. coli and P. aeruginosa were far higher than that of LVFX. In rats, area under the plasma concentration-time curve from zero to 4 h (AUC0-4h) of LVFX after oral administration of LVFX-CLX was 1.34-fold higher than that after LVFX, though it did not reach significance level. Co-administration of Al3+ with LVFX and LVFX-CLX in rats decreased AUC0-4h of plasma LVFX by 75% and 60%, respectively, however, the AUC0-4h of plasma LVFX after co-administration of LVFX-CLX and Al3+ was 2.2-times higher than that after co-administration of LVFX and Al3+. These results suggested that the use of LVFX-CLX may reduce the modulation of intestinal microflora caused by LVFX and the suppressive effect of Al3+ on intestinal absorption of LVFX.


Assuntos
Alumínio/química , Antibacterianos/farmacocinética , Levofloxacino/farmacocinética , Administração Oral , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Área Sob a Curva , Disponibilidade Biológica , Escherichia coli/efeitos dos fármacos , Ésteres/química , Absorção Intestinal , Levofloxacino/administração & dosagem , Levofloxacino/química , Masculino , Testes de Sensibilidade Microbiana , Pró-Fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos
3.
Malays Orthop J ; 14(2): 111-119, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32983385

RESUMO

INTRODUCTION: Post-operative acute kidney injury is a serious complication and identifying modifiable factors could assist in peri-operative management. This study aimed to identify the pre-operative and intra-operative factors associated with the incidence of post-operative acute kidney injury and acute deterioration of kidney function after total hip arthroplasty.Materials and methods: This single-center, retrospective, observational study included 203 patients who underwent unilateral primary total hip arthroplasty. Acute kidney injury was determined using biochemical markers according to the risk, injury, failure, loss of kidney function, and end-stage kidney disease (RIFLE) criteria. Acute deterioration of kidney function was defined as the reduction of estimated glomerular filtration rate by ≥10ml/min/1.73m2. RESULTS: Prior to total hip arthroplasty, 20% of all patients met the chronic renal dysfunction criterion of glomerular filtration rates <60ml/min/1.73m2 (glomerular filtration rate categories G3a-G5). Incidence rates of acute kidney injury and acute deterioration of kidney function after total hip arthroplasty were 0.49% and 6.9%, respectively. Multivariate regression analysis showed that diabetes mellitus and use of nonsteroidal anti-inflammatory drugs before total hip arthroplasty were significant risk factors for acute deterioration of kidney function. Advanced age, preoperative renal dysfunction, antihypertensive, diuretics, or statin use, operation time, total blood loss, type of anesthetic, and body mass index were not significant risk factors. CONCLUSION: Diabetes mellitus and use of nonsteroidal anti-inflammatory drugs were controllable risks, and multidisciplinary approaches are a reasonable means of minimising peri-operative acute kidney injury or acute deterioration of kidney function.

4.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 205-212, Jan.-Feb. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-888098

RESUMO

O presente trabalho avaliou o papel do baço no armazenamento e na reativação das linhagens de células B, representadas por células IgM positivas imunomarcadas no tecido esplênico, bem como a funcionalidade dessas células, sobre a cinética dos linfócitos e na produção sistêmica de anticorpos em tilápias-do-nilo (Oreochromis niloticus). Foram separados dois grupos: grupo memória, constituído por peixes previamente imunizados com hemácia de carneiro a 2,5%, para a geração da memória imune, e o grupo naive, que recebeu o mesmo volume de solução salina a 0,65%. Após 32 dias, os dois grupos foram submetidos a uma nova dose do antígeno na mesma concentração, volume e via de inoculação. A reativação dos clones de memória foi evidenciada pelo aumento do número de células IgM positivas no baço do grupo memória no dia zero/pré-imune. Além disso, o mesmo grupo apresentou aumento dos títulos de anticorpos séricos no 14º dia e no número absoluto de linfócitos no 21º dia em relação ao grupo naive. Esses resultados sugerem que o baço não seja apenas um local de armazenamento, mas também de reativação de células B de memória em tilápia-do-nilo.(AU)


This work aimed to evaluate the role of the spleen in storage and reactivation of the memory B cells, represented by IgM positive cells and the systemic production of sheep antibodies anti-red cell in Nile tilapia (Oreochromis niloticus). Two groups were established: the memory group, containing fish previously immunized with a 2,5% sheep anti-red cell, to generate the immune memory; and the naive group, containing fish that received a 0,65% saline solution. After 32 days, both groups were subjected to a new dose of the same antigen at the same concentration, volume, and inoculation via. The memory clones reactivation was correlated to the increase of the IgM positive cells in the spleen in the memory group at 0 day. The memory group showed an increase in the absolute number of lymphocytes at 21 days and an increase in the antibodies at 14 days after inoculation when compared to the naive group. The results suggest that the spleen may be a storage and reactivation place of memory B cells in Nile tilapia.(AU)


Assuntos
Animais , Imunoglobulina M/análise , Ciclídeos/imunologia , Ciclídeos/sangue , Formação de Anticorpos , Imunoglobulinas/administração & dosagem
5.
Arq. bras. med. vet. zootec ; 68(2): 379-386, mar.-abr. 2016. graf
Artigo em Português | LILACS | ID: lil-779794

RESUMO

A bactéria Streptococcus agalactiae é um potente agente causador de surtos por doenças bacterianas em peixes. O estresse provocado pelo manejo zootécnico e pela má qualidade ambiental torna a tilápia susceptível às infecções por essa bactéria. O objetivo do presente trabalho foi avaliar a resistência de tilápias-do-nilo imunizadas com soro hiperimune anti-S. agalactiae, posteriormente desafiadas com cepa homóloga da mesma bactéria. Após determinação da DL 50 de S. agalactiae, 36 tilápias foram distribuídas em quatro aquários, dois para o grupo controle e dois para inoculação celomática para produção de anticorpos anti-S. agalactiae. No 21° e 28° dias, foi coletado sangue para obtenção de soro hiperimune utilizado na transferência passiva. Em seguida, 30 tilápias foram distribuídas em três aquários e submetidas a três tratamentos: GI: controle; GII: imunizadas com o soro inativado; GIII: imunizadas com soro ativo...


The Streptococcus agalactiae bacteria is a potent agent which causes outbreaks of bacterial diseases in fish. The stress caused by management and poor environmental quality makes tilapia susceptible to infections, including by bacterium. The aim of this study was to evaluate the resistance of the Nile tilapia immunized with hyperimmune serum against S. agalactiae subsequently challenged with homologous strain of the same bacteria. After determining the DL 50 of S. agalactiae, 36 tilapias were distributed in 4 aquariums, 2 for the control group and 2 for the group via coelomic, inoculated with the DL 50 for anti-S. agalactiae antibodies production. On the 21st and 28th day blood was collected for the obtainment of hiperimmune serum used in passive transference. Then, 30 tilapias were distributed in 3 aquariums submitted to 3 treatments (GI: control; GII: immunized with inactivated-serum; GIII: immunized with non-inactivated serum)...


Assuntos
Animais , Ciclídeos , Peixes , Infecções Bacterianas/veterinária , Streptococcus agalactiae/patogenicidade , Surtos de Doenças/veterinária , Anticorpos/análise , Infecções Bacterianas , Imunização Passiva/veterinária , Imunoglobulinas/análise
6.
Clin Exp Allergy ; 46(7): 992-1003, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26892276

RESUMO

BACKGROUND: The relationship among natural allergen exposure, induction of blocking antibody and the occurrence of atopic allergy-particularly in the presence of IgE production-is debatable. OBJECTIVE: To clarify the relationship between the dose of cutaneous exposure to dust mite allergen and susceptibility to the IgE-mediated allergic response in relation to IgG production. METHODS: NC/Nga mice were epicutaneously exposed to various doses of Dermatophagoides pteronyssinus allergen to induce atopic dermatitis-like skin lesions. We then evaluated the skin lesions, induction of mite-specific immune responses, and susceptibility to anaphylaxis. RESULTS: Dose-dependent exacerbation of atopic dermatitis-like skin lesions and increases in mite-specific IgG and IgE production were observed. However, mice exposed to relatively low doses of mite allergen showed hypersusceptibility to mite allergen-specific anaphylaxis. We also showed that adoptive transfer of total IgG from Dp-sensitized mice rescued mice from the hypersusceptibility seen in those exposed to low doses of mite allergen. CONCLUSIONS AND CLINICAL RELEVANCE: High-dose cutaneous exposure to dust mites induced effective blocking IgG production, even if accompanied by IgE production. Our data might support the concept that an increase in IgG titre, not a decrease in IgE titre, is a marker of clinical improvement in allergen-specific immunotherapy.


Assuntos
Alérgenos/administração & dosagem , Alérgenos/imunologia , Anafilaxia/prevenção & controle , Anticorpos Bloqueadores/imunologia , Antígenos de Dermatophagoides/administração & dosagem , Antígenos de Dermatophagoides/imunologia , Imunoglobulina G/imunologia , Anafilaxia/imunologia , Anafilaxia/metabolismo , Animais , Especificidade de Anticorpos/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Imunização , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Camundongos
7.
Opt Lett ; 37(6): 1130-2, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22446248

RESUMO

Strong hard (ε>100 keV) x rays being observed from impulse atmospheric discharges with maximal voltages from U=0.5 to 0.9 MV just before the breakdown were completely stopped with the use of femtosecond-laser-filament plasma. Runaway electrons generating such x rays and being estimated to achieve their maximal energy, ε~U, near the positive electrode disappear if a laser filament plasma is ignited perpendicularly to the runaway near the positive electrode. A preheating mechanism for formation of the electron runaway in air is proposed.

8.
Clin Nephrol ; 60(4): 257-65, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14579940

RESUMO

Patients with diabetic nephropathy have an increased risk of coronary heart disease (CHD). Paraoxonase (Pon1) is a high-density lipoprotein- (HDL) associated enzyme that protects low-density lipoprotein from oxidation and also protects against atherosclerosis. We investigated the relationship of serum Pon1 activity, Pon1 Q192R polymorphism and HDL-C level to type 2 diabetes mellitus (DM) in patients on maintenance hemodialysis (HD). DM patients (n = 56, F/M = 17/39, aged 64.5 +/- 7.5 years) and non-DM patients (n = 89, F/M = 28/61, aged 62.7 +/- 8.3 years) under HD were included in this study. Salt-stimulated serum Pon1 activities were measured using paraoxon as a substrate. Pon1 Q192R polymorphism was detected by the mutagenically separated polymerase chain reaction. DM patients on HD had significantly lower HDL-C levels and serum Pon1 activities than non-DM patients on HD (657 +/- 277 vs. 763 +/- 257 IU/l, p < 0.01). The distribution of Pon1 Q 192R genotypes in all subjects did not differ from that predicted from the Hardy-Weinberg equilibrium. Serum Pon1 activities in both DM and non-DM patients on HD were regulated by Pon1 Q192R polymorphism: RR > QR > QQ. However, the reduced Pon1 activities in DM patients on HD were related to DM independent of the Pon1 genotype: reduced Pon1 activity was related to DM in RR carriers. Serum Pon1 activities were positively correlated with HDL-C levels. The association between HDL-C and DM in hemodialyzed patients was independent of Pon1 activity as assessed by an analysis of variance. But the relation between Pon1 activity and DM was modified by HDL-C levels: significantly when HDL-C was below 50 mg/dl, but not significantly when HDL-C was above 50 mg/dl. The results of a logistic regression analysis show that reduced serum Pon1 activities and low HDL-C levels were additively associated with DM. In conclusion, Pon1 status and HDL levels are independently associated with DM in patients on hemodialysis and may contribute to the increased risk of CHD in diabetic nephropathy.


Assuntos
Arildialquilfosfatase/fisiologia , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Polimorfismo Genético/genética , Diálise Renal , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/complicações , Feminino , Genótipo , Humanos , Nefropatias/complicações , Nefropatias/metabolismo , Nefropatias/terapia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos
9.
J Lab Clin Med ; 138(3): 177-85, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11528370

RESUMO

Systemic inhibition of nitric oxide synthase (NOS) in streptozotocin-induced (STZ-induced) diabetic rats results in decreases in glomerular filtration rate (GFR) and renal plasma flow (RPF) and an increase in renal vascular resistance (RVR). However, the exact isoform of NOS involved in diabetic renal hyperfiltration has not been determined. This study was conducted to clarify whether NO derived from neuronal NOS is involved in diabetic renal hyperfiltration when using a selective inhibitor of neuronal NOS, 7-nitro indazole (7-NI). Continuous infusion of NG-nitro-L -arginine methyl ester (L-NAME) at 5 microg/kg/min ameliorated renal hyperfiltration, decreased RPF, and increased RVR in diabetic rats without affecting the mean arterial pressure (MAP). 7-NI administered intraperitoneally in diabetic rats significantly reduced GFR without affecting MAP, but the renal hyperfiltration was still observed after the administration of 7-NI. The combined administration of L-NAME after 7-NI caused a further decrease in GFR in diabetic rats and ultimately resulted in normalization of GFR. 7-NI did not change any parameters of renal hemodynamics in control rats. Urinary excretion of nitrite/nitrate and cyclic guanosine monophosphate was significantly increased in diabetic rats over values found in control rats. Our results suggested that a local inhibition of NO in the kidney was involved in the amelioration of diabetic renal hyperfiltration and that NO derived from neuronal NOS is involved, at least in part, in renal hyperfiltration in STZ-induced diabetic rats.


Assuntos
Diabetes Mellitus Experimental/enzimologia , Inibidores Enzimáticos/farmacologia , Taxa de Filtração Glomerular/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , GMP Cíclico/urina , Sinergismo Farmacológico , Hemodinâmica/efeitos dos fármacos , Indazóis/farmacologia , Infusões Intravenosas , Injeções Intraperitoneais , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Nitratos/urina , Óxido Nítrico Sintase Tipo I , Nitritos/urina , Ratos , Ratos Sprague-Dawley , Fluxo Plasmático Renal/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos
10.
J UOEH ; 23(1): 23-34, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11279838

RESUMO

The present paper describes the metabolism of a chiral drug propranolol (PL) using isolated hepatocytes freshly prepared from untreated, PB- or 3-MC-pretreated rats. In order to examine not only the existence of enantioselectivity but also the effect of enzyme inducer (PB or 3-MC) on PL metabolism, 500 microM PL (RS-PL, R(+)-PL or S(-)-PL) was incubated at 37 degrees C using 8 x 10(6) cells/ml isolated rat hepatocytes. Then, the elimination amount of PL and the formation amounts of eight kinds of the metabolites including ring hydroxylated metabolites (4-OH-, 5-OH- and 7-OH-PL) and side chain metabolites (NDP, AcNDP, PGL, NLA and NAA) were simultaneously determined by HPLC. By 3-MC- and PB-pretreatment, a significant increase was noticed in PL elimination and also in the formation of PL metabolites, NDP, NLA and NAA. Furthermore, the presence of enantioselectivity was observed, i.e. the substrate R(+)-PL was always eliminated faster than the substrate S(-)-PL. Regarding the metabolite formation, NDP, AcNDP and NAA were dominantly produced from R(+)-PL, and NLA, PGL and the ring hydroxylated metabolites from S(-)-PL. In all cases of PL elimination and the metabolite formation, the amounts of the metabolites derived from RS-PL indicated the mean values of the respective amounts derived from R(+)-PL and S (-)-PL. Using the three kinds of isolated rat hepatocytes mentioned above, the kinetic parameters of NDP-formation at 37 degrees C for 10 min were calculated using RS-PL, R(+)-PL or S(-)-PL as a substrate. From the pseudo values of V'max/K'm (microliter/min.8 x 10(6) cells), the easiest formation of NDP from R(+)-PL was observed in the rat hepatocyte system pretreated with 3-MC.


Assuntos
Fígado/metabolismo , Propranolol/metabolismo , Animais , Células Cultivadas , Fígado/citologia , Ratos
11.
Hepatol Res ; 19(2): 131-143, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11164738

RESUMO

Host immunomodulation through T cell action may play a pivotal role in determining the response to interferon (IFN) therapy for chronic hepatitis C. We examined whether the early changes in the host immune response were helpful in predicting the final effect in 31 patients with chronic hepatitis C receiving IFN. IFN treatment significantly reduced the serum levels of intercellular adhesion molecule-1 (ICAM-1) and E-selectin, and significantly increased those of vascular cell adhesion molecule-1 (VCAM-1) and interleukin-2 receptor alpha (IL-2Ralpha) in the first 7-10 days. Serum levels of these immunological parameters did not correlate with serum alanine aminotransferase (ALT) when evaluated with either absolute values or relative values (over pre-treatment value), implying that our results are not just secondary to improvement in hepatic inflammation. The relative changes (Delta) in these parameters reflected the long-term response to IFN therapy, i.e. the lower the change, the more effective the therapy was. Among these serum parameters, DeltaIL-2Ralpha within the first 7-10 days of IFN treatment was the most useful parameter in predicting the response to therapy. In conclusion, a dynamic immunomodulation during the early phase of IFN therapy may determine the subsequent long-term response to IFN therapy.

12.
Diabetes Nutr Metab ; 14(6): 308-14, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11853362

RESUMO

Sulphonylureas are known to enhance insulin secretion from the pancreas and its sensitivity of the extrapancreatic target organs. In this study, we clarified a direct extrapancreatic effect of the sulphonylureas and of gliclazide, on the glucose transport system in cultured rat L6 myoblasts, which predominantly expressed glucose transporter 1 (GLUT 1). Our results show that gliclazide stimulated 2-deoxy-[3H]-D-glucose (2DG) uptake, 24 h after treatment, in a dose-dependent manner, and it also increased GLUT 1 protein synthesis and mRNA expression; 2DG uptake and GLUT 1 protein synthesis induced by gliclazide were completely blocked by protein kinase A (PKA) inhibitors (H89 and rp-cAMP), and gliclazide increased the intracellular cAMP levels 3 to 24 hr after the treatment. These results show that in rat L6 myoblasts, gliclazide stimulates glucose transport activity by the induction of GLUT 1 gene expression through PKA.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Gliclazida/farmacologia , Hipoglicemiantes/farmacologia , Proteínas de Transporte de Monossacarídeos/genética , Músculos/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Desoxiglucose/metabolismo , Inibidores Enzimáticos/farmacologia , Transportador de Glucose Tipo 1 , Proteínas de Transporte de Monossacarídeos/análise , RNA Mensageiro/análise , Ratos , Trítio
13.
Toxicol Appl Pharmacol ; 169(2): 151-8, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11097867

RESUMO

Our study was designed to clarify whether renal functional reserve (RFR) was impaired in rats chronically treated with oral low-dose cadmium (Cd). Rats (n = 15) were treated with 1 ppm of cadmium chloride added to drinking water. We measured RFR (representing the ability to increase glomerular filtration rate [GFR] and renal plasma flow [RPF] in response to infusion of glycine) at 2 and 10 months after initiation of exposure to Cd. Urinary excretion of Cd was significantly higher in 10-month Cd-treated rats than in age-matched control rats (provided with distilled water only). Weight gain was noted in Cd-treated rats, which was identical to that in age-matched control rats. Urinary volume and urinary excretions of sodium, protein, and glucose were similar in the two groups. There were no differences in the basal mean arterial pressure (MAP) and renal hemodynamics between 2-month Cd-treated and age-matched control rats. Infusion of glycine resulted in significant increases in GFR and RPF and a significant reduction in renal vascular resistance (RVR) in both 2-month Cd-treated and age-matched control rats (control, GFR: 133 +/- 10%, RPF: 148 +/- 8%; 2-month Cd-treated rats, GFR: 152 +/- 12% and RPF: 154 +/- 7%). The basal MAP and renal hemodynamics in 10-month Cd-treated rats were also identical to those in age-matched control rats. Infusion of glycine significantly increased GFR in 10-month control rats (132 +/- 15%), but not in 10-month Cd-treated rats (98 +/- 11%), but did not change MAP, RPF, and RVR in both groups. In addition to age-related pathological changes, mild renal interstitial edema and degenerative mitochondria with diminished matrix density and loss of the cristae in the proximal tubular cells were more frequent in 10-month Cd-treated rats. Our results suggest that long-term oral intake of low-dose Cd in rats exacerbate age-related impairment of renal functional reserve and degeneration of the proximal tubular epithelial cells.


Assuntos
Envelhecimento/fisiologia , Cádmio/toxicidade , Rim/fisiologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Hematócrito , Rim/efeitos dos fármacos , Rim/ultraestrutura , Masculino , Microscopia Eletrônica , Ratos , Ratos Sprague-Dawley , Fluxo Plasmático Renal/efeitos dos fármacos , Urodinâmica/efeitos dos fármacos
14.
Arthritis Rheum ; 43(11): 2513-22, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11083275

RESUMO

OBJECTIVE: To investigate whether synovial cells from rheumatoid arthritis (RA) synovium can be divided into 2 functionally different subpopulations: active or proliferative cells and apoptotic cells. METHODS: Expression of cell surface and cytoplasmic molecules on synovial cells was assessed by immunohistochemistry, flow cytometry, or Western blotting. Cells were categorized as intercellular adhesion molecule 1 (ICAM-1) positive or negative based on positive and negative selection of antibody-coated beads. Cell cycle and apoptosis were assessed using propidium iodide staining, TUNEL method, and DNA fragmentation. RESULTS: Expression of ICAM-1 and Fas was noted mainly in the synovial lining to sublining layer in vivo, and synovial cells could be clearly distinguished as ICAM-1 positive or negative. The expression of Fas was higher on ICAM-1-positive cells than on ICAM-1-negative cells in vitro. The functional and phenotypic heterogeneity between ICAM-1-positive and -negative cells was further emphasized by cell cycle machinery. The majority of ICAM-1-positive cells were arrested at the G0/G1 phase, whereas many of the ICAM-1-negative cells were at the S to G2/M proliferating phase. In ICAM-1-positive cells, p53 and p21 expression was up-regulated and cyclin-dependent protein kinase 6 activity was inhibited. Most ICAM-1-positive cells were apoptotic (as evidenced by TUNEL positivity and DNA fragmentation). ICAM-1-positive cells were induced not only by interleukin-1beta, but also by Fas crosslinking. CONCLUSION: ICAM-1-positive synovial cells represent growth arrest and subsequent apoptosis, whereas ICAM-1-negative cells are proliferative. Such differences in regulation of the cell cycle based on ICAM-1 status are important determinants of the lifespan, proliferation, and growth arrest of RA synoviocytes.


Assuntos
Artrite Reumatoide/patologia , Quinases Ciclina-Dependentes , Molécula 1 de Adesão Intercelular/análise , Membrana Sinovial/citologia , Apoptose/fisiologia , Ciclo Celular/fisiologia , Divisão Celular/fisiologia , Quinase 6 Dependente de Ciclina , Regulação para Baixo , Expressão Gênica/fisiologia , Genes bcl-2 , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Interleucina-1/farmacologia , Interfase/efeitos dos fármacos , Interfase/fisiologia , Osteoartrite/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Membrana Sinovial/metabolismo , Membrana Sinovial/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Regulação para Cima , Receptor fas/biossíntese
16.
J Bone Miner Res ; 15(10): 1912-23, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11028443

RESUMO

The concept of differential regulation of certain adhesion molecules on different cell subsets and their relevance to cell functions has emerged in recent years. The initial event in bone remodeling is an increase in osteoclastic bone resorption and cell adhesion between osteoclastic precursors and bone marrow stromal cells or osteoblasts is known to commit the osteoclast development. Here, we show that human osteoblasts can be divided into two subsets based on the expression of the intercellular adhesion molecule (ICAM)-1; ICAM-1+ osteoblasts highly adhered to monocytes, including osteoclast precursors, produced osteoclast differentiation factor (ODF), and induced multinuclear osteoclast-like cell formation. Anti-ODF monoclonal antibody (mAb) did not inhibit the adhesion of monocytes to osteoblastic cells, whereas anti-leukocyte function-associated antigen (LFA)-1, a receptor for ICAM-1, mAb blocked the adhesion. We thereby propose that the higher affinity adhesion via LFA-1/ICAM-1 is prerequisite for efficient function of membrane-bound ODF during osteoclast maturation. The functional characteristics of ICAM-1+ osteoblasts were emphasized further by cell cycle regulation, as manifested by (i) up-regulation of p53 and p21, (ii) reduction of activity of cyclin-dependent kinase (cdk) 6, (iii) underphosphorylation of retinoblastoma protein, (iv) increased Fas but reduced bcl-2 expression, and (v) majority of cells remained at G0/G1 phase. Furthermore, ICAM-1+ osteoblasts were induced by interleukin-1beta (IL-1beta). Taken together, we propose that the differentiation of osteoblasts to ICAM-1+ subpopulation by inflammatory cytokines plays an important role in osteoporosis, which is observed in patients with chronic inflammation, because ICAM-1+ osteoblasts can bias bone turnover to bone resorption, committing osteoclast maturation through cell adhesion with its precursor, and the majority of ICAM-1+ osteoblasts arrested at G0/G1 phase. Such regulation of cell cycle arrest also is an important determinant of the life span of cells in bone in which continuous bone remodeling maintains its homeostasis.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Molécula 1 de Adesão Intercelular/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Proteínas de Transporte/metabolismo , Adesão Celular , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Quinases Ciclina-Dependentes/metabolismo , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Imunofluorescência , Expressão Gênica , Humanos , Molécula 1 de Adesão Intercelular/genética , Interleucina-1/farmacologia , Interleucina-6/metabolismo , Glicoproteínas de Membrana/metabolismo , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Osteoblastos/classificação , Osteoblastos/efeitos dos fármacos , Osteocalcina/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Fosforilação , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
17.
Endocr J ; 47(3): 293-302, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11036873

RESUMO

Interleukin-4 (IL-4) inhibits the spontaneous and stimulated bone resorption resulting from the inhibition of osteoclast formation, as well as osteoclastic activity. Since IL-13 shares some biological properties with IL-4, it was recently reported that IL-13 inhibits bone resorption. The present study was designed to determine the effects of murine IL-4 (IL-4) and murine IL-13 (IL-13) on the murine osteoblastic cell line MC3T3-E1. IL-4 and IL-13 stimulated 3H-thymidine incorporation in the MC3T3-E1 cells and its proliferation in dose dependent manners. A spontaneous increase in alkaline phosphatase (ALP) activity in the cells after plating was inhibited by IL-4 or IL-13, and both cytokines blunted an increase in ALP activity by human parathyroid hormone (PTH) (1-34). PTH-stimulated cyclic AMP (cAMP) production was inhibited by pretreatment with IL-4 and IL-13 for 48 hr in dose dependent manners. Pretreatment with IL-4 and IL-13 for 48 hr caused a decrease in PTH-induced cAMP production at any stimulatory concentration. However, the effective dose (ED50) was unchanged by the pretreatment with these cytokines. Pretreatment with IL-4 and IL-13 did not modulate cAMP generation by forskolin. In contrast, cAMP generation by PGE2 is greater in the cells treated with the cytokines compared to those without the cytokines. These results indicate that IL-4 and IL-13 act on MC3T3-E1 cells in the same manner, stimulating cell proliferation, but inhibiting cell differentiation. The inhibition of osteoblast differentiation by IL-4 and IL-13 may be associated with a decrease in PTH actions on osteoblasts.


Assuntos
Interleucina-13/farmacologia , Interleucina-3/farmacologia , Osteoblastos/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , AMP Cíclico/metabolismo , Dinoprostona/farmacologia , Humanos , Camundongos , Osteoblastos/metabolismo , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Timidina/metabolismo
18.
J Clin Endocrinol Metab ; 85(8): 2775-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10946880

RESUMO

In hyperthyroid Graves' disease, short-term methimazole is sufficient to induce lasting remission in some patients, but even long-term treatment fails to do so in others. We have evaluated the role of autoimmune abnormalities in the helper T cell type 2 (TH2)-interleukin-13 (IL-13)-TSH receptor system in maintaining hyperthyroidism by comparing IgE levels in patients with various thyroid diseases. One hundred and ninety-three patients with hyperthyroid Graves' disease were treated with methimazole, and blood samples were obtained to measure serum levels of T4, T3, TSH, thyroglobulin, antimicrosomal antibody, TSH binding inhibitory Ig (TBII), thyroid-stimulating antibody, thyroid stimulation-blocking antibody, IgE, interferon-gamma, IL-4, and IL-13. Elevation of serum IgE (> or = 170 U/mL) was found in 35.5% of patients with hyperthyroid Graves' disease, and serum levels of T4, T:1, antimicrosomal antibody, and TBII were significantly greater in patients with IgE elevation than in those with normal serum IgE. During methimazole treatment, there was a parallel decrease in the serum T4 concentration in the presence or absence of an IgE elevation. However, there was a significantly smaller decrease in TBII in patients with elevated IgE than in those with normal IgE. As a result, the remission rate was significantly greater in patients with normal IgE than in those with IgE elevation. Serum levels of IL-13 were elevated in 64.7% of patients with IgE elevation in the absence of detectable TH1 marker, interferon-gamma. These findings suggest that in one third of patients with hyperthyroid Graves' disease, TH2 cells are stimulated and secrete excess amounts of IL-13, which subsequently stimulates B cells to synthesize more TSH receptor antibody and IgE, so that during methimazole treatment TBII decreases less in patients with IgE elevation, producing a lower remission rate.


Assuntos
Doença de Graves/imunologia , Imunoglobulina E/sangue , Metimazol/uso terapêutico , Células Th2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antitireóideos/uso terapêutico , Biomarcadores/sangue , Feminino , Bócio/sangue , Bócio/imunologia , Bócio Nodular/sangue , Bócio Nodular/imunologia , Doença de Graves/sangue , Doença de Graves/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Tireoidite Autoimune/sangue , Tireoidite Autoimune/imunologia , Tiroxina/sangue , Fatores de Tempo , Tri-Iodotironina/sangue
19.
Hepatology ; 32(2): 278-88, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10915734

RESUMO

Primary graft nonfunction of steatotic liver allograft is one of the factors causing shortage of donor livers. Ischemia/reperfusion (I/R) injury is an important contributory factor to primary graft nonfunction. In this study, we investigated the complex chain of events from transcription factor activation to necrosis through cytokine induction and apoptosis in steatotic rat liver after warm I/R. Rats with alcoholic or nonalcoholic fatty liver were subjected to hepatic warm I/R and compared with control rats. Rats fed an ethanol diet for 6 to 8 weeks developed severe hepatic necrosis accompanied by increased neutrophil recruitment after I/R, compared with rats with nonalcoholic fatty liver or control. Hepatic apoptosis as assessed by DNA fragmentation at 4 hours after I/R, however, increased to a similar degree in each of the 2 fatty liver models compared with the control. Alcoholic fatty liver exposed to I/R showed a rapid increase in nuclear factor-kappaB (NF-kappaB) binding activity at 1 hour after I/R, which preceded an increased expression of tumor necrosis factor alpha (TNF-alpha) and cytokine-induced neutrophil chemoattractant-1 (CINC-1). In contrast, nonalcoholic fatty liver did not show such potentiation of either NF-kappaB activation or cytokine induction after I/R. Our results have indicated that alcoholic fatty liver may differentially induce CINC-1 production and hepatic necrosis after I/R. Furthermore, our results suggest that apoptosis per se does not always lead to necrosis in the liver following I/R.


Assuntos
Quimiocinas CXC , Quimiocinas/genética , Fígado Gorduroso Alcoólico/patologia , Peptídeos e Proteínas de Sinalização Intercelular , Isquemia/patologia , Fígado/patologia , Neutrófilos/fisiologia , Traumatismo por Reperfusão/patologia , Animais , Apoptose , Quimiocina CXCL1 , Fatores Quimiotáticos/genética , Fígado Gorduroso Alcoólico/metabolismo , Substâncias de Crescimento/genética , Fígado/irrigação sanguínea , Masculino , NF-kappa B/fisiologia , Necrose , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Fator de Transcrição AP-1/fisiologia , Fator de Necrose Tumoral alfa/genética
20.
Neuroendocrinology ; 71(6): 366-74, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10878498

RESUMO

Starvation induces a decrease in circulating leptin levels and activation of the hypothalamus-pituitary-adrenal (HPA) axis. Leptin inhibits the HPA axis in unfed rodents or genetically leptin-deficient ob/ob mice, whereas it stimulates corticotropin-releasing hormone (CRH) gene expression in the paraventricular nucleus (PVN). However, the interactions between leptin, CRH and the HPA axis are poorly understood and are likely to be complex. We recently demonstrated that central leptin administration caused increases in plasma arginine-vasopressin (AVP) and AVP gene expression of the PVN in nonstressful rats. AVP stimulates the release of adrenocorticotropic hormone (ACTH), but it also potentiates the action of CRH on ACTH release. In this study, we investigated the effects of leptin on plasma ACTH and corticosterone levels, CRH mRNA of the PVN and proopiomelanocortin (POMC) mRNA of the pituitary in nonstrained rats. Intracerebroventricularly administered leptin caused increases in plasma ACTH and corticosterone levels in dose-dependent manners. In Northern blot analyses, the leptin injection induced significant increases in the expression of CRH mRNA in the PVN and POMC mRNA in the pituitary. The increased plasma ACTH and corticosterone levels by leptin were attenuated with intracerebroventricular pretreatment of a V(1a) receptor antagonist (OPC-21268) or a V(1a)/V(1b) receptor antagonist (dP[Tyr(Me)(2)]AVP), but not with that of a V(2) receptor antagonist (OPC-31260). The leptin-induced CRH mRNA expression in the PVN and POMC mRNA expression in the pituitary were also reduced by the pretreatment with OPC-21268 and dP[Tyr(Me)(2)]AVP. These results suggest that intracerebroventricular leptin administration activates the HPA axis by AVP receptor activation through V(1a) receptors in the PVN which in turn activates CRH neurons to drive ACTH and corticosterone secretion in concert with AVP in nonstrained rats.


Assuntos
Arginina Vasopressina/fisiologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Leptina/farmacologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Hormônio Adrenocorticotrópico/sangue , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos , Northern Blotting , Corticosterona/sangue , Sondas de DNA , Injeções Intraventriculares , Leptina/administração & dosagem , Masculino , Pró-Opiomelanocortina/biossíntese , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Estimulação Química
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