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1.
Lett Appl Microbiol ; 67(1): 64-71, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29604211

RESUMO

This study aims to obtain secondary metabolites extracts from filamentous fungi isolated from soil and marine sediments from Antarctica and assess its potential antibacterial activity on Xanthomonas citri subsp. citri, the agent of citrus canker. Metabolites production was conducted in Malt 2% broth at 15°C for 20 days after which intracellular and extracellular extracts were obtained. The extracts were evaluated by cell viability assays through Resazurin Microtitre Assay. From 158 fungal extracts, 33 hampered bacterial growth in vitro. The average inhibition of the extracts obtained from terrestrial (soil) and marine (sediments) fungi was 94 and 97% respectively. These inhibition values were close to the average of 90% cell death for the positive control. MIC90 and MBC for the bioactive extracts were established. Isolates that produced active metabolites against the phytopathogen were identified using molecular taxonomy (ITS-rRNA sequencing) as: Pseudogymnoascus, Penicillium, Cadophora, Paraconiothyrium and Toxicocladosporium. Antarctic fungal strains isolated from terrestrial and marine sediments were able to produce secondary metabolites with antimicrobial activity against X. citri subsp. citri, highlighting the importance of these microbial genetic resources. These metabolites have potential to be used as alternatives for the control of this plant pathogen. SIGNIFICANCE AND IMPACT OF THE STUDY: This manuscript makes an impact on the study of micro-organisms from extreme habitats and their possible contribution in discovering new active molecules against pathogens of agricultural interest. Studies on the Antarctic continent and its communities have attracted the scientific community due to the long period of isolation and low levels of disturbance that surrounds the region. Knowing the potential of fungi in this region to produce active secondary metabolites, we aim to contribute to the discovery of compounds with antibacterial action in Xanthomonas citri subsp. citri, a plant pathogen present in several regions around the globe.


Assuntos
Antibacterianos/farmacologia , Antibiose/fisiologia , Extratos Celulares/farmacologia , Fungos/metabolismo , Xanthomonas/crescimento & desenvolvimento , Regiões Antárticas , Antibacterianos/metabolismo , Citrus/microbiologia , Sedimentos Geológicos/microbiologia , Testes de Sensibilidade Microbiana , Doenças das Plantas/microbiologia , Microbiologia do Solo , Xanthomonas/genética
2.
Lett Appl Microbiol ; 66(6): 530-536, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29527704

RESUMO

This study aims to obtain secondary metabolites extracts from filamentous fungi isolated from soil and marine sediments from Antarctic ecosystems and to assess its potential antibacterial activity on Xanthomonas euvesicatoria and Xanthomonas axonopodis pv. passiflorae (phytopathogenic bacteria causing diseases in pepper and tomato and passionfruit, respectively). Among the 66 crude intracellular and extracellular extracts obtained from fungi recovered from soil and 79 obtained from marine sediment samples, 25 showed the ability to prevent the growth of X. euvesicatoria in vitro and 28 showed the ability to prevent the growth of X. axonopodis pv. passiflorae in vitro. Intracellular and extracellular extracts from soil fungi inhibited around 97% of X. euvesicatoria and 98% of X. axonopodis pv. passiflorae at 2·1 mg ml-1 . The average inhibition rates against X. euvesicatoria and X. axonopodis pv. passiflorae for intracellular and extracellular extracts from marine sediments fungi were around 96 and 97%, respectively, at 3·0 mg ml-1 . Extracts containing secondary metabolites with antimicrobial activity against X. euvesicatoria and X. axonopodis pv. passiflorae were obtained, containing possible substitutes for the products currently used to control these phytopathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: Micro-organisms from extreme ecosystems, such as the Antarctic ecosystem, need to survive in harsh conditions with low temperatures, low nutrients and high UV radiation. Micro-organisms adapt to these conditions evolving diverse biochemical and physiological adaptations essential for survival. All this makes these micro-organisms a rich source of novel natural products based on unique chemical scaffolds. Discovering novel bioactive compounds is essential because of the rise in antibiotic-resistant micro-organisms and the emergence of new infections. Fungi from Antarctic environments have been proven to produce bioactive secondary metabolites against various micro-organisms, but few studies have shown activity against Xanthomonas phytopathogens.


Assuntos
Antibacterianos/farmacologia , Capsicum/microbiologia , Extratos Celulares/farmacologia , Fungos/metabolismo , Passiflora/microbiologia , Doenças das Plantas/microbiologia , Solanum lycopersicum/microbiologia , Xanthomonas axonopodis/efeitos dos fármacos , Regiões Antárticas , Fungos/química , Sedimentos Geológicos/microbiologia , Microbiologia do Solo , Xanthomonas axonopodis/isolamento & purificação
4.
Am J Transplant ; 8(7): 1557-61, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18510644

RESUMO

Postoperative liver failure is a rare complication after living donor liver resection. This is a case report of a 22-year-old healthy donor who was rescued with liver transplantation 11 days after right hemihepatectomy. Nine months later the patient is alive, and has fully recovered from his multiple organ failure. According to a review of the literature, there are four additional living liver donors, who received a liver transplant. Our own patient is the only survivor, so far. This case demonstrates that even in supposedly healthy living donors postoperative complications cannot be completely prevented. Although liver failure is rare in these patients, timely transplantation may need to be considered as the only life-saving treatment.


Assuntos
Hepatectomia/efeitos adversos , Falência Hepática/etiologia , Transplante de Fígado , Doadores Vivos , Insuficiência de Múltiplos Órgãos/etiologia , Adulto , Feminino , Humanos
5.
Am J Med Sci ; 320(5): 337-41, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11093688

RESUMO

Falciparum malaria is frequently associated with significant morbidity and mortality. The use of exchange transfusion as a therapeutic modality for severe cases of malaria has been described previously. We describe a case of a 49 year-old African American gentleman with a history of hemoglobin-SC disease who presented with a severe case of Plasmodium falciparum malaria 3 weeks after having received an infected blood transfusion. His peripheral smear showed the presence of numerous intraerythrocytic ring forms and "banana-shaped" gametocytes with a high-grade parasitemia, estimated at 18%. He was treated with antimalarial chemotherapy and also underwent a 12-unit red blood cell exchange transfusion, decreasing his parasite load to < 1%, as determined on repeat smear. It is prudent to be aware of the efficacy of this adjunctive treatment, especially with ever-increasing travel and a resultant increase in the prevalence of tropical diseases in the United States.


Assuntos
Transfusão de Eritrócitos , Eritrócitos/parasitologia , Transfusão Total , Malária Falciparum/sangue , Malária Falciparum/terapia , Reação Transfusional , Negro ou Afro-Americano , Animais , Humanos , Masculino , Pessoa de Meia-Idade , Parasitemia/sangue , Parasitemia/terapia , Plasmodium falciparum/fisiologia
6.
Endocrine ; 12(1): 81-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10855695

RESUMO

Estrogen deficiency following ovariectomy or menopause results in bone loss. Although evidence strongly suggests that the immune system is involved in the pathogenesis of estrogen-deficient osteoporosis, it is not clear what role, if any, the T-lymphocyte plays in this process. Therefore, we examined the distribution of T-cell subsets in lymphoid organs and tissues, under varying estrogenic states in the rat. Six-month-old female Sprague-Dawley rats, ovariectomized (Ovx) and sham-operated, were randomized 5 d post-surgery into six groups to receive the following treatments: (A) sham/placebo; (B) sham/low-dose E2; (C) sham/high-dose E2; (D) Ovx/placebo; (E) Ovx/low-dose E2; (F) Ovx/high-dose E2. Half of the treated rats (groups A-F) were sacrificed on d 14; the remainder on d 28. Following euthanasia, mononuclear cells were isolated from the thymus, peripheral blood, spleen, lymph node and bone marrow, and were labeled for flow cytometric analysis using mouse anti-rat monoclonal antibodies directed against CD5, CD4, and CD8 antigenic markers. In the thymus, ovariectomy caused a dramatic increase and E2 treatment caused a dose-dependent decrease in weight that was proportional to the number of thymocytes. In the bone marrow, ovariectomy caused a significant reduction in the percentage of all T-cell subsets examined and this effect persisted throughout the duration of the study. Estrogen replacement therapy at the low-dose reversed the effects of ovariectomy and high-dose E2 treatment caused an increase in T-cell subsets in both the sham and Ovx groups, an effect that was more pronounced at d 14 compared with d 28. Although the percentages of some T-cell subsets in the other lymphoid organs/tissues were altered by ovariectomy or E2 treatment at d 0 and 14, all these changes had normalized by d 28 except for CD5 and CD4 cells in peripheral blood. In summary, with the exception of T-lymphocytes in the bone marrow, the effects of varying estrogenic states on T-cells were variable and transient. The influence of estrogen status on bone marrow T-lymphocytes suggests that these cells may play a role in mediating the effects of estrogen on bone turnover and warrant additional studies focusing on the functional role of T-cells in the bone marrow compartment.


Assuntos
Estradiol/farmacologia , Estrogênios/deficiência , Estrogênios/fisiologia , Tecido Linfoide/citologia , Ovariectomia , Linfócitos T/fisiologia , Animais , Células da Medula Óssea , Antígenos CD4/análise , Antígenos CD5/análise , Antígenos CD8/análise , Separação Celular , Estradiol/administração & dosagem , Feminino , Citometria de Fluxo , Linfonodos/citologia , Contagem de Linfócitos , Placebos , Ratos , Ratos Sprague-Dawley , Baço/citologia , Linfócitos T/imunologia , Timo/citologia
7.
Arch Intern Med ; 160(7): 1033-6, 2000 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10761970

RESUMO

The clinical and pathological findings of idiopathic ductopenia were studied in a 30-year-old woman who initially manifested jaundice and pruritus. Serum biochemical tests of liver function indicated severe and progressive cholestasis. Viral hepatitis markers and circulating autoantibodies were absent. The patient had a normal cholangiogram and lacked evidence of inflammatory bowel disease. Histological examination of a liver specimen showed severe cholestasis and absence of interlobular bile ducts. Severe jaundice and intractable pruritus developed in the patient and served as the indications for liver transplantation 4 months after initial examination. Transplantation resulted in prompt and complete resolution of the jaundice and pruritus. Two types of idiopathic adulthood ductopenia associated with different prognoses are recognized. Patients with type 1 idiopathic adulthood ductopenia are asymptomatic or manifest symptoms of cholestatic liver disease. They tend to have less destruction of the intrahepatic bile ducts on liver biopsy specimens. Their clinical course ranges from spontaneous improvement to progression to biliary cirrhosis. In contrast, patients with type 2 idiopathic adulthood ductopenia generally manifest initial symptoms of decompensated biliary cirrhosis, have extensive destruction of the intrahepatic bile ducts on liver biopsy, and frequently require orthotopic liver transplantation.


Assuntos
Colestase Intra-Hepática/diagnóstico , Cirrose Hepática Biliar/diagnóstico , Transplante de Fígado , Adulto , Colestase Intra-Hepática/complicações , Colestase Intra-Hepática/patologia , Colestase Intra-Hepática/cirurgia , Feminino , Humanos , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/patologia , Cirrose Hepática Biliar/cirurgia , Prurido/etiologia
8.
Ann Emerg Med ; 33(6): 715-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10339689

RESUMO

We describe a case of sparteine intoxication associated with using a preparation from lupine seeds. A female patient of Portuguese origin presented to the emergency department with classic anticholinergic signs after ingestion of a lupine seed extract. She took the preparation with the belief it represented a cure for her recently diagnosed diabetes. Analysis of the patient's lupine bean extract identified the preponderant compound as oxo-sparteine by gas chromatography/mass spectrometry. Intoxication by lupine seeds rarely occurs in human beings. To our knowledge, no medical or toxicologic evidence supports a belief that lupine extract could lower serum glucose levels. This case highlights the need for emergency care providers to be aware of the health hazards that can be associated with the use of such home remedies.


Assuntos
Antagonistas Colinérgicos/intoxicação , Diabetes Mellitus/terapia , Tratamento de Emergência/métodos , Fabaceae/intoxicação , Fitoterapia , Plantas Medicinais/intoxicação , Sementes/intoxicação , Esparteína/intoxicação , Idoso , Diabetes Mellitus/etnologia , Diagnóstico Diferencial , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Philadelphia , Intoxicação/diagnóstico , Intoxicação/terapia , Portugal/etnologia
9.
Bone ; 21(1): 65-70, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9213009

RESUMO

Post-transplantation bone disease is an increasingly recognized clinical entity whose etiology is multifactorial. The immunosuppressant agent cyclosporine-A (CsA) has repeatedly been shown experimentally to induce a high-turnover osteopenic state. Alendronate (Alen.) is a new generation bisphosphonate having far greater antiresorptive potency than previous bisphosphonates. It inhibits osteoclast resorption in vitro and in vivo without adversely affecting bone mineralization. This study was designed to investigate whether alendronate could prevent CsA-induced osteopenia in the rat. Forty-eight 8-month-old male Sprague Dawley rats were randomized into four groups to receive the following for 28 days: (1) CsA vehicle (veh.) p.o. daily and alendronate vehicle subcutaneously (s.c.) twice/week, (2) CsA 15 mg/kg p.o. daily and Alen. veh. s.c. twice/week, (3) Alen. 70 micrograms/kg s.c. twice/ week and CsA veh. p.o. daily, and (4) CsA 15 mg/kg p.o. daily and Alen. 70 micrograms/kg s.c. twice/week. Rats were weighed and bled and serum was assayed serially for calcium, PTH, 1,25(OH)2vit.D, and osteocalcin. Tibiae were removed following sacrifice on day 28, after double demeclocycline and calcein labeling, for histomorphometric analysis. Treated groups were compared to the vehicle-treated control. We confirmed previous findings that CsA produces elevated 1,25(OH)2 vitamin D and serum osteocalcin levels. Alendronate treatment by itself decreased osteocalcin by day 28 and resulted in a marginal decrease in serum total calcium on day 14. The histomorphometry findings reconfirmed that the administration of CsA induces a state of high-turnover osteopenia. Alendronate prevented CsA's adverse effects, particularly in maintaining trabecular bone volume, presumably by decreasing bone remodeling. Alendronate would seem to hold therapeutic promise in post-transplantation bone disease.


Assuntos
Alendronato/uso terapêutico , Doenças Ósseas Metabólicas/prevenção & controle , Ciclosporina/toxicidade , Imunossupressores/toxicidade , Administração Oral , Alendronato/administração & dosagem , Alendronato/farmacologia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Calcitriol/sangue , Cálcio/sangue , Ciclosporina/administração & dosagem , Modelos Animais de Doenças , Processamento de Imagem Assistida por Computador , Imunossupressores/administração & dosagem , Injeções Subcutâneas , Masculino , Osteocalcina/sangue , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Hormônio Paratireóideo/sangue , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Tíbia/citologia , Tíbia/efeitos dos fármacos , Tíbia/metabolismo , Tíbia/patologia
10.
J Clin Endocrinol Metab ; 82(4): 1202-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9100597

RESUMO

The purpose of our study was to determine the effects of GH and insulin-like growth factor I (IGF-I) administration singly and in combination on vertebral, tibial, and femoral bone in aged female monkeys as well as the various treatment effects on serum hormone levels and osteocalcin gene expression. Twenty-one ovulating female monkeys (rhesus macaque), aged 16-20 yr (5-6 kg), were divided into four groups to receive the following treatment for 7 weeks via Alzet pumps inserted sc: A, eluant (control group); B, recombinant human IGF-I (rhIGF-I; 120 micrograms/kg.day); C) rhGH (100 micrograms/kg.day); D, combination of rhIGF-I (120 micrograms/kg.day) and rhGH (100 micrograms/kg.day). Serum was assayed serially for glucose, IGF-I, GH, and IGF-binding protein-3 levels. All groups received double labeling with calcein. On the day of death, the primates' second lumbar vertebrae, tibiae, and femora were carefully dissected, fixed in 70% ethanol, and subjected to histomorphometric analysis. Ribonucleic acid was extracted from contralateral tibiae for the purpose of osteocalcin gene expression analysis. Serum glucose was unaffected by treatment. Serum GH was significantly elevated in groups C and D, whereas serum IGF-I and IGFBP-3 were only significantly increased in group D. Histomorphometric analysis showed no significant differences or trends for bone volume in any treatment group. Bone formation rate, surface and/or bone volume referent were significantly higher in both groups treated with GH (C and D) in tibia and femur, with a similar trend in vertebrae. The increase in bone formation rate was due mainly to a significant increase in mineral apposition rate, but there was also an increase in tibial mineralizing surface by GH by factorial analysis (P < 0.05). There were significant treatment effects on osteoid surface and osteoclastic surface in femur in the combination treatment group vs. the controls. Osteocalcin gene expression analysis supported an enhanced expression in both groups treated with GH. These findings are consistent with a short term effect of GH to increase bone remodeling and predominantly osteoblastic activity in the appendicular skeleton. In contrast, other than an isolated increase in osteoclastic surface in femoral bone, IGF-I, when administered alone, was unable to significantly influence bone formation or resorption activity in this short term study.


Assuntos
Osso e Ossos/efeitos dos fármacos , Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Animais , Osso e Ossos/anatomia & histologia , Feminino , Expressão Gênica , Hormônio do Crescimento/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Macaca mulatta , Osteocalcina/genética , Osteogênese/efeitos dos fármacos , RNA Mensageiro/metabolismo , Proteínas Recombinantes , Fatores de Tempo
11.
J Bone Miner Res ; 12(4): 607-15, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9101372

RESUMO

Our laboratory has demonstrated that the immunosuppressants Cyclosporin A (CsA) and tacrolimus (FK506), in vivo in the rat, produce a high-turnover osteopenia. CsA is known to decrease serum testosterone (Test) levels both in the rat and in human transplant patients. Less is known of FK506's effect on androgens. CsA-induced hypogonadism may contribute to the aforementioned bone loss because hypogonadism itself is a risk factor for osteoporosis and fracture. The aim of this study was to assess serum androgen levels following CsA and FK506 therapy and to see wether Test replacement therapy, in the form of 28-day controlled release subcutaneous pellet implants, could prevent CsA-induced osteopenia. Two experiments were conducted. In experiment I, four groups of 6-month-old male Sprague-Dawley rats received the following: (A) CsA vehicle and placebo pellet, (B) Test 15 mg pellet and CsA vehicle, (C) CsA 10 mg/kg and placebo pellet, (D) Test 15 mg pellet and CsA 10 mg/kg. In experiment II, two groups of rats received (E) FK506 vehicle and (F) FK506 4 mg/kg. CsA, FK506, and vehicles were given for 28 days by daily oral gavage. The rats were weighted and bled on days 0, 14, and 28. All rats received double fluorescent labeling, and on day 28 the tibiae were removed for histomorphometry. Whole blood was assayed for CsA and FK506 levels. Serum was assayed for total and free Test as well as for osteocalcin (BGP), blood urea nitrogen (BUN), creatinine, and calcium. Whole blood monoclonal CsA levels measured by fluorescent immunoassay were in the therapeutic range, while a drug concentration profile showed good absorption of FK506. Those rats receiving Test and FK506 lost weight, while those receiving CsA remained constant. BUN was only marginally elevated in the CsA-treated groups on day 28 (p < 0.05), while creatinine was unchanged. On day 28, total and free Test was significantly reduced in the CsA-treated rats versus control (p < 0.05), while Test replacement therapy maintained total Test levels above vehicle (p < 0.01) and free Test levels similar to vehicle on day 28. FK506 did not lower total or free Test levels. BGP levels were significantly increased in the CsA (p < 0.01) and FK506 (p < 0.001) groups on day 28. BGP in the groups receiving Test alone and in combination with CsA remained similar to vehicle. Histomorphometry confirmed CsA- and FK506-induced high-turnover osteopenia. The Test alone group marignally increased bone formation. Test replacement failed to prevent the CsA-induced bone loss. In conclusion, immunosuppressive doses of CsA, but not FK506, lowers serum total and free Test. Hypoandrogenemia does not seem to be a major factor in CsA-induced osteopenia because bone loss occurs despite Test replacement.


Assuntos
Doenças Ósseas Metabólicas/induzido quimicamente , Ciclosporina/efeitos adversos , Imunossupressores/efeitos adversos , Testosterona/sangue , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal , Doenças Ósseas Metabólicas/tratamento farmacológico , Cálcio/sangue , Creatinina/sangue , Sinergismo Farmacológico , Humanos , Masculino , Transplante de Órgãos/efeitos adversos , Osteocalcina/sangue , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Ratos , Ratos Sprague-Dawley , Tacrolimo/efeitos adversos , Tacrolimo/sangue , Testosterona/uso terapêutico
12.
J Bone Miner Res ; 12(3): 479-86, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9076592

RESUMO

Our laboratory has previously demonstrated that the T-lymphocyte is critical in the development of cyclosporin A-induced osteopenia in the rat model. A similar state of osteopenia is induced by estrogen depletion in the ovariectomized (OVX) rat, which is the animal model of postmenopausal bone loss. However, the role of the immune system, and particularly the T-lymphocyte, in estrogen deplete osteopenia has not been elucidated. We used the Rowett athymic nude rat as our model of T-lymphocyte deficiency. In this study, the experimental rats were divided into four groups as follows: (1) sham-operated Rowett heterozygous (rnu/+) euthymic rats (control group); (2) OVX Rowett heterozygous (rnu/+) euthymic rats; (3) sham-operated Rowett homozygous (rnu/rnu) athymic nude rats, which are T-lymphocyte deficient; and (4) ovariectomized Rowett homozygous (rnu/rnu) rats. Rats were weighed, and venous blood was taken in weeks 2, 4, and 6 for determination of serum osteocalcin. Serum 1,25-dihydroxyvitamin D (1,25(OH)2D) was determined on the day of sacrifice. Following sacrifice, histomorphometry was performed on double-labeled proximal tibial metaphyses. Flow cytometric analysis of splenic mononu-clear cell isolates stained for OX19-positive (CD5) T-lymphocytes was performed. T-lymphocyte analysis revealed significant reductions in both athymic nude groups, while OVX euthymic rats demonstrated a diminished number of T-cells relative to their sham-operated counterparts. Histomorphometric data indicated that both OVX groups exhibited a significant loss of trabecular volume, with associated increases in indices for bone formation and resorption, with resorption likely outstripping formation, resulting in osteopenia. Serum osteocalcin was significantly elevated in the ovariectomized euthymic group throughout the experimental period compared with the control group (p < 0.01); it was elevated in the ovariectomized athymic group on week 4 only (p < 0.01 vs. control). It appears that the T-lymphocyte may not be an essential component in the pathogenesis of estrogen deficiency osteopenia. The contribution of circulating T-lymphocytes as well as other T-lymphocyte-rich organs needs to be explored further.


Assuntos
Doenças Ósseas Metabólicas/fisiopatologia , Estrogênios/deficiência , Ovário/fisiologia , Linfócitos T/imunologia , Animais , Peso Corporal/fisiologia , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/patologia , Ciclosporina , Modelos Animais de Doenças , Feminino , Osteocalcina/sangue , Ovariectomia , Ratos , Ratos Nus , Tíbia/patologia , Vitamina D/análogos & derivados , Vitamina D/sangue
13.
Bone ; 19(4): 381-6, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8894144

RESUMO

Cyclosporine (CsA) is a potent immunosuppressant that has revolutionized the success of organ transplantation. Flurbiprofen (FB), a propionic acid derivative NSAID, has been demonstrated in vivo to reduce osteoclast numbers in normal rats. The aim of this experiment was to determine whether addition of FB to CsA-treated rats could prevent the bone changes associated with CsA therapy. Forty-eight 10-12-week-old male Sprague-Dawley rats were randomized to receive, daily for 28 days: (1) CsA vehicle p.o. plus FB vehicle sc; (2) CsA (15 mg/kg) p.o. plus FB vehicle sc, (3) CsA vehicle p.o. plus FB (1.5 mg/kg) sc; and (4) CsA (15 mg/kg) p.o. plus FB (1.5 mg/kg) sc. Rats were weighed and venous blood sampled at baseline, 14 days, and 28 days for determination of glucose, Ca+2, BUN, creatinine, PTH, osteocalcin, and 1,25(OH)2 vitamin D. Tibiae were removed following killing, after double labeling for histomorphometry. Body mass was significantly lower than control in all rats receiving CsA on days 14 and 28 while blood glucose was only elevated in the CsA alone group. Day 28 BUN and creatinine were significantly elevated in the CsA group and the combination of CsA and FB revealed an exacerbation of this trend. Vitamin D and osteocalcin were consistently increased in the CsA and CsA/FB groups. Bone histomorphometry showed evidence of trabecular osteopenia in CsA and CsA/FB groups. CsA alone resulted in elevated bone turnover. FB was unable to prevent the trabecular bone loss induced by CsA therapy. This experiment indicates no role for FB as a therapeutic option in CsA-induced bone disease at the given doses and duration of treatment by virtue of its lack of bone sparing ability and adverse renal effects when the two drugs are administered concurrently.


Assuntos
Anti-Inflamatórios não Esteroides/toxicidade , Ciclosporina/toxicidade , Flurbiprofeno/toxicidade , Imunossupressores/toxicidade , Osteoclastos/efeitos dos fármacos , Osteoporose/induzido quimicamente , Administração Oral , Análise de Variância , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Calcitriol/sangue , Cálcio/sangue , Contagem de Células , Creatinina/sangue , Ciclosporina/administração & dosagem , Flurbiprofeno/administração & dosagem , Ensaio Imunorradiométrico , Imunossupressores/administração & dosagem , Injeções Subcutâneas , Rim/efeitos dos fármacos , Rim/patologia , Testes de Função Renal , Masculino , Osteocalcina/sangue , Osteoclastos/citologia , Hormônio Paratireóideo/sangue , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Tíbia/citologia , Tíbia/efeitos dos fármacos , Tíbia/patologia
14.
J Bone Miner Res ; 11(8): 1191-8, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8854256

RESUMO

Cyclosporin A (CsA) administered to the oophorectomized (Ox) rat exacerbates the high turnover osteopenia associated with estrogen deficiency. 17 beta-estradiol replacement therapy prevent this bone loss. The aim of this study was to see whether an estrogen-like compound, Raloxifene analog (LY117018 HCL, Ral) could likewise ameliorate CsA-induced osteopenia in the Ox rat. Sixty 6-month-old Sprague-Dawley rats, divided into five groups, underwent oophorectomy. One group acted as a basal group and the others received either vehicle (group B), CsA 15 mg/kg/day (group C), Ral 3 mg/kg/day (group D), or CsA 15 mg/kg/day and Ral 3 mg/kg/day (group E) for 28 days by gavage. A sixth sham operated group of 12 rats received vehicle only (group A). Rats were weighed and bled on days 0, 14, and 28 for measurement of ionized calcium, glucose, osteocalcin (BGP), 17 beta-estradiol, and 1,25-dihydroxyvitamin D3 (1,25[OH]2D3). Tibiae were removed on day 28 for bone histomorphometry after double tetracycline and calcein labeling. Oophorectomy caused a significant gain in weight in groups B and C which was prevented by Ral in groups D and E. Randomized blood glucose levels and 1,25(OH)2D3 levels were elevated in both CsA-treated groups. Blood ionized calcium levels were lower in vehicle (group B) compared with sham (group A) on day 28. Ox (group B) had significantly higher serum BGP levels compared with sham-operated rats. Serum BGP levels were further elevated in group C compared with vehicle and were lowered in both Ral-treated groups to vehicle levels by day 28. Bone histomorphometry revealed a high turnover osteopenia with increased parameters of bone formation and resorption and loss of cancellous bone volume postoophorectomy (group B). CsA (group C) exacerbated the effects of oophorectomy. Ral (group D) completely prevented the high turnover osteopenia caused by oophorectomy and was able to attenuate substantially the effects of CsA in the Ox rat (group E). Ral therapy ameliorated CsA-induced osteopenia in the Ox rat and might prove a useful agent in preventing bone loss in postmenopausal women receiving CsA.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Antagonistas de Estrogênios/farmacologia , Ovário/fisiologia , Pirrolidinas/farmacologia , Receptores de Estrogênio/agonistas , Tiofenos/farmacologia , Animais , Doenças Ósseas Metabólicas/induzido quimicamente , Osso e Ossos/efeitos dos fármacos , Ciclosporina , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Antagonistas de Estrogênios/efeitos adversos , Estrogênios/deficiência , Feminino , Fígado/efeitos dos fármacos , Ovariectomia , Pirrolidinas/efeitos adversos , Ratos , Ratos Sprague-Dawley , Tiofenos/efeitos adversos , Útero/efeitos dos fármacos
15.
Calcif Tissue Int ; 59(1): 38-44, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8661983

RESUMO

Immunosuppression with cyclosporin A (CsA) is effective in a number of immune-mediated diseases and in preventing rejection following organ transplantation. We have repeatedly demonstrated that CsA in the rat model produces accelerated bone remodelling with net bone loss, best characterized in trabecular bone. IGF-I holds promise as a treatment for various osteopenic conditions. Although currently a subject of much controversy, various studies have suggested that in vivo it is anabolic to cortical as well as trabecular bone. The purpose of this study was, in part, to further characterize the effects of CsA and IGF-I on trabecular and cortical bone, and to see whether systemic IGF-I is able to modulate CsA's deleterious skeletal effects. Sixty 10 week-old, male, Sprague-Dawley rats were randomized to receive the following daily for 3 weeks: (1) CsA vehicle (veh) per os (po) + recombinant human (rh) IGF-1 veh subcutaneously (sc); (2) CsA 15 mg/kg po + rhIGF-I-veh; (3) CsA-veh + rhIGF-I 200 microg/kg sc; (4) CsA-veh + rhIGF-I 600 microg/kg sc; (5) CsA 15 mg/kg + rhIGF-I 200 microg/kg, and (6) CsA 15 mg/kg + rhIGF-I 600 microg/kg. Rats were weighed and venous blood was sampled serially for determination of glucose, ionized calcium (Ca2+), PTH, vitamin D, and osteocalcin. Following sacrifice on day 20, histomorphometry was performed on double calcein-labeled tibial metaphysis and diaphysis. All rats receiving CsA had elevated levels of blood glucose and osteocalcin by day 9 and vitamin D at day 20. PTH was similar in all groups, and Ca2+ was only raised in the CsA and CsA + IGF-I 200 microg/kg groups. Rats receiving IGF-I 200 microg/kg and IGF-I 600 microg/kg gained more weight than either vehicle- or CsA-treated animals, attesting to IGF-1's anabolic properties. CsA caused severe trabecular bone loss, not prevented by IGF-I; it even further increased the eroded surface. CsA and IGF-I had little effect on cortical bone volume or marrow area. IGF-I increased endocortical matrix synthesis, as evidenced by the increases in the percent endocortical osteoid perimeter, an effect negated by the addition of CsA. This experiment demonstrates that trabecular bone is more susceptible than cortical bone to the deleterious effects of CsA and indicates little role for IGF-1 in the pathophysiology or treatment of CsA-induced bone disease at the given doses and duration of treatment.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Ciclosporina/toxicidade , Fator de Crescimento Insulin-Like I/uso terapêutico , Animais , Glicemia , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/prevenção & controle , Reabsorção Óssea/terapia , Cálcio/metabolismo , Ciclosporina/antagonistas & inibidores , Humanos , Masculino , Osteocalcina/sangue , Hormônio Paratireóideo/metabolismo , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos , Aumento de Peso
16.
Dtsch Tierarztl Wochenschr ; 99(11): 452-4, 1992 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1459034

RESUMO

1118 Friesian cows and 101 Friesian heifers were investigated in internal pelvic measurements and their relationships to external measurements. The mean of the pelvic vertical and the medium diagonally diameter of the pelvis are 19.8 cm and 18.3 cm. 363.9 square centimetres and 76.3 centimetres were found for the pelvic surface and pelvic circumference. The difference between the biggest and smallest pelvis was 295.0 square centimetres. Medium to high coefficiences of correlation were detected between the internal pelvic measurements but relationships between internal and external pelvic measurements were low. From determined external pelvic measurements only the hip breadth provides usefull informations of the pelvic shape.


Assuntos
Bovinos/anatomia & histologia , Ossos Pélvicos/anatomia & histologia , Pelve/anatomia & histologia , Animais , Feminino
17.
Anesthesiology ; 52(1): 78-80, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7352651
18.
Artigo em Inglês | MEDLINE | ID: mdl-344293

RESUMO

Spatial distribution of pulmonary blood flow (SDPBF) during 2- to 3-min exposures to 6-8 Gy acceleration was studied, using radioactive microspheres in dogs, and compared to previously reported 1 Gy control distributions. Isotope distributions were measured by scintiscanning individual 1-cm-thick cross sections of excised, fixed lungs. Results indicate: 1) the fraction of cardiac output traversing left and right lungs did not change systematically with the duration and magnitude of acceleration; but 2) the fraction is strongly affected by the occurrence or absence of fast deep breaths, which cause an increase or decrease, respectively, in blood flow through the dependent lung; and 3) Gy acceleration caused a significant increase in relative pulmonary vascular resistance (PVR) in nondependent and dependent regions of the lung concurrent with a decrease in PVR in the midsagittal region of the thorax. Result 3 may be mediated primarily by changes in regional alveolar volume and geometry in the nondependent hemithorax conbined with hydrostatic effects of extravascular fluid and active hypoxic response in the dependent region and is superimposed on, and may override, hydrostatic effects of perfusion pressures on SDPBF during acceleration.


Assuntos
Gravitação , Circulação Pulmonar , Resistência Vascular , Adaptação Fisiológica , Animais , Débito Cardíaco , Cães , Técnica de Diluição de Corante , Pulmão/fisiologia , Medidas de Volume Pulmonar , Fluxo Sanguíneo Regional
19.
Artigo em Inglês | MEDLINE | ID: mdl-632161

RESUMO

Regional displacements of lung parenchyma due to respiratory movements at 1 G and 7 Gy were studied in anesthetized dogs in the left decubitus position in a water-filled respirator that provided control of respiratory volumes and rate and minimized inertial shifts in position and shape of the thorax and abdominal contents and related effects on the lungs. Inspiratory movements at 1 G were relatively uniform, although regional volume increased more in the nondependent (right) lung than in the dependent (left) lung. Regional functional residual capacity (FRC) increased in the nondependent lung and decreased in the dependent lung during exposures to 7 Gy. The greatest inspiratory increase in volume occurred near the midlung, where regional FRC changed the least during acceleration. The decrease in dependent and increase in nondependent lung volumes during acceleration are attributed to the increased weight and consequent downward displacement of the higher specific gravity mediastinal contents concomitantly with upward displacement of pulmonary gas, producing an exaggeration of the dependent-to-nondependent gradient in alveolar size.


Assuntos
Adaptação Fisiológica , Gravitação , Pulmão/fisiologia , Animais , Cães , Medidas de Volume Pulmonar , Masculino , Postura , Respiração
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