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1.
Biomed Pharmacother ; 154: 113615, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057219

RESUMO

AIMS: Hospitalization for heart failure treatment (HHF) is an incisive event in the course of HF. Today, the large majority of HHF patients is ≥ 65 years and discharge HF drugs are most often not applied at dose levels acknowledged to provide prognostic benefit. This study therefore aims to investigate the treatment effect size of discharge HF drugs in old HHF patients. METHODS: Drugs are analyzed according to pharmacological class. Individual discharge HF drug dose is reported as percentage of guidelines-recommended target dose. Primary endpoint was 1-year all-cause mortality (ACM) after discharge; the secondary endpoint combined 1-year ACM and first cardiovascular hospitalization within 1 year after discharge. Comparison between 65-80 years and > 80 years old study participants tested the relative treatment effect size as a function of respective age group. RESULTS: The 875 consecutive HHF patients had a median age of 82 years [76-87 years]; 48.6 % were females. Betablocker and diuretic treatment did not change the incidence of endpoints. Inhibition of the renin-angiotensin system (RASi), when compared to no treatment, decreased the incidence of endpoints both at the 1-25 % and the > 25 % target dose level. Antagonists of the mineralocorticoid receptor (MRA), when compared to no treatment, decreased the secondary endpoint at the 1-25 % target dose level but not at the > 25 % target dose level. The relative treatment effect size of RASi or MRA corresponded between the age strata for both endpoints. CONCLUSION: Low-dose RASi and MRA had beneficial effects in these old HHF patients.


Assuntos
Insuficiência Cardíaca , Sistema Renina-Angiotensina , Idoso de 80 Anos ou mais , Aldosterona , Angiotensinas , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Hospitalização , Humanos , Masculino , Renina , Volume Sistólico
2.
Curr Oncol ; 20(5): 265-72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24155631

RESUMO

BACKGROUND: Downsizing strategies are often attempted for patients with hepatocellular carcinoma (hcc) before liver transplantation (lt). The objective of the present study was to determine clinical predictors of favourable survival outcomes after transarterial chemoembolization (tace) before lt for hcc outside the Milan criteria, so as to better select candidates for this strategy. METHODS: In this retrospective study, patients with hcc tumours either beyond Milan criteria (single lesion > 5 cm, 3 lesions with 1 or more > 3 cm) or at the upper limit of Milan criteria (single lesions between 4.1 cm and 5.0 cm), with a predicted waiting time of more than 3 months, received carboplatin-based tace treatments. Exclusion criteria for tace included Child-Pugh C cirrhosis or the presence of portal vein invasion or extrahepatic disease on imaging. Only patients without tumour progression after tace underwent lt. RESULTS: Of 160 hcc patients who received liver grafts between 1997 and 2010, 35 were treated with tace preoperatively. The median of the sum of tumour diameters was 6.7 cm (range: 4.8-8.5 cm), which decreased with tace to 5.0 cm (range: 3.3-7.0 cm) at transplantation (p < 0.0004). The percentage drop in alpha-fetoprotein (αfp) was a positive predictor (p = 0.0051) and the time from last tace treatment to transplantation was a negative predictor (p < 0.0001) for overall survival. CONCLUSIONS: The percentage drop in αfp and a shorter time from the final tace treatment to transplantation significantly predicted improved overall survival after lt for hcc downsized with tace. As a serum marker, αfp should be followed when tace is used as a strategy to stabilize or downsize hcc lesions before lt.

3.
Eur J Cancer Care (Engl) ; 18(5): 466-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19473375

RESUMO

OBJECTIVE: Patients with Von Recklinghausen's disease (neurofibromatosis type 1) are at increased risk of developing various tumours. However, the coexistence of neurofibromatosis with small-bowel adenocarcinoma is exceedingly rare. We present an uncommon case of neurofibromatosis type 1, involving the small bowel in a 73-year-old man, who was admitted to our department with signs of acute abdomen. At laparotomy, multiple mesenteric and intramural nodules were seen in the distal ileum. These nodules obstructed ileal lumen, while the intestine wall was perforated in one point. A wide resection of the affected ileum together with all visible nodules in the adjacent mesentery was performed. Histology revealed neurofibromatosis type 1 with malignant transformation to small-bowel adenocarcinoma. The patient had no additional therapy. In a follow-up of 2 years, the patient is very well and there was no recurrence of the disease. We suggest that adenocarcinoma of small bowel should be considered in the evaluation of acute abdominal pain in neurofibromatosis patients.


Assuntos
Adenocarcinoma/patologia , Neoplasias do Íleo/patologia , Intestino Delgado/patologia , Neoplasias Primárias Múltiplas/patologia , Neurofibromatose 1/patologia , Abdome Agudo/etiologia , Idoso , Seguimentos , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/patologia , Masculino , Tomografia Computadorizada por Raios X
4.
Am J Transplant ; 8(12): 2558-68, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19032224

RESUMO

Orthotopic liver transplantation (OLT) continues to be the only remedy for end-stage liver disease. In an attempt to decrease the ever-widening gap between organ donor and recipient numbers, and ultimately make more livers amenable to transplantation, we characterized the healthy human liver's response to ischemia and reperfusion-induced injury during transplantation. This was carried out by transcriptional profiling using cDNA microarray to identify genes whose expression was modulated at the 1-h postreperfusion time point. We observed that the map kinase phosphatase-1/dual-specificity phosphatase-1 (MKP-1/DUSP1) mRNA was strongly and significantly upregulated. Validation of this observation was carried out using reverse transcriptase-polymerase chain reaction (RT-PCR), immunoblotting and immunohistochemistry. In addition, we characterized the signaling pathways regulating MKP-1 expression using the human hepatoma cell line HepG2. Finally, by combining MKP-1 silencing with reperfusion-associated stresses, we reveal the preferential role of this protein in attenuating the activity of the JNK and p38(MAPK) pathways, and the resulting apoptosis, making MKP-1 a potential target for therapeutic intervention.


Assuntos
Fosfatase 1 de Especificidade Dupla/metabolismo , Transplante de Fígado/fisiologia , Fígado/metabolismo , Traumatismo por Reperfusão/metabolismo , Apoptose/fisiologia , Biópsia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Fosfatase 1 de Especificidade Dupla/genética , Humanos , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , MAP Quinase Quinase 4/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
HPB (Oxford) ; 8(1): 67-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-18333243

RESUMO

BACKGROUND: A 29-year-old woman who presented with fatigue and jaundice was found to have an obstructing mass at the bifurcation of the bile duct. The patient underwent a successful left hepatectomy with resection of the bile duct bifurcation and a reconstruction with a right hepaticojejunostomy. Pathology revealed an atypical carcinoid tumour of the left extrahepatic bile duct, with perineural and lymphatic invasion. The patient subsequently developed multiple metastases in the remaining liver. METHODS: In the absence of extrahepatic disease, the patient underwent a successful liver transplant. RESULTS: Two years later she remains disease-free. DISCUSSION: To our knowledge this is the first report of a biliary carcinoid treated with hepatectomy and finally with liver transplantation, with excellent results. The biological behaviour of these rare tumours mandates aggressive surgical management.

6.
Mol Biol Cell ; 16(4): 1629-39, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15659649

RESUMO

Rho GTPases are mainly known for their implication in cytoskeleton remodeling. They have also been recently shown to regulate various aspects of membrane trafficking. Here, we report the identification and the characterization of a novel Caenorhabditis elegans Cdc42-related protein, CRP-1, that shows atypical enzymatic characteristics in vitro. Expression in mouse fibroblasts revealed that, in contrast with CDC-42, CRP-1 was unable to reorganize the actin cytoskeleton and mainly localized to trans-Golgi network and recycling endosomes. This subcellular localization, as well as its expression profile restricted to a subset of epithelial-like cells in C. elegans, suggested a potential function for this protein in polarized membrane trafficking. Consistent with this hypothesis, alteration of CRP-1 expression affected the apical trafficking of CHE-14 in vulval and rectal epithelial cells and sphingolipids (C(6)-NBD-ceramide) uptake and/or trafficking in intestinal cells. However, it did not affect basolateral trafficking of myotactin in the pharynx and the targeting of IFB-2 and AJM-1, two cytosolic apical markers of intestine epithelial cells. Hence, our data demonstrate a function for CRP-1 in the regulation of membrane trafficking in a subset of cells with epithelial characteristics.


Assuntos
Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Proteína cdc42 de Ligação ao GTP/química , Proteínas rho de Ligação ao GTP/química , Proteínas rho de Ligação ao GTP/metabolismo , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico , Caenorhabditis elegans/química , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Membrana Celular/química , Citoesqueleto/metabolismo , Desenvolvimento Embrionário , Endossomos/química , Endossomos/genética , Endossomos/metabolismo , Células Epiteliais/química , Células Epiteliais/citologia , Camundongos , Dados de Sequência Molecular , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Mutação/genética , Células NIH 3T3 , Filogenia , Alinhamento de Sequência , Proteínas rho de Ligação ao GTP/genética , Rede trans-Golgi/química , Rede trans-Golgi/metabolismo
7.
Transplant Proc ; 36(6): 1766-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15350473

RESUMO

BACKGROUND: The cellular events following liver ischemia/reperfusion (I/R) during transplantation are largely unknown. The spectrum of I/R damage to the liver can be clinically revealed by the development of primary graft dysfunction or nonfunction. Because viral-induced liver necrosis has been associated with the development of calcifications in an animal model, we investigated the spectrum of I/R changes identified at an ultrastructural level among livers after liver transplant (LT). MATERIALS AND METHODS: Random liver biopsies from five recipients with different degrees of liver dysfunction (LD) were processed for light (LM) and electron (EM) microscopic examination. The degree of calcification was estimated as mild-moderate or severe. The degree of cell vacuolization, used as a surrogate marker of cell necrosis, was reported as mild-moderate or severe. RESULTS: Two patients with severe LD had obvious calcifications by LM and EM examinations. Both showed significant vacuole formation, suggesting a severe degree of cell necrosis, and both succumbed to the sequelae of their LD. One patient showed evidence of mild calcifications at EM (but not LM) examination, with mild vacuole formation. The remaining two patients displayed no microcalcifications. Both presented only mild vacuole formation. Both patients recovered from LD and are currently alive. CONCLUSION: In this preliminary report, we conclude that the clinically observed degree of LD after orthotopic liver transplant (OLT)correlates well with ultrastructural modifications. These include calcification and vacuole formation. We believe that both findings can be used as surrogate markers of a clinically significant hepatic I/R injury.


Assuntos
Transplante de Fígado/patologia , Traumatismo por Reperfusão/patologia , Biópsia , Calcinose/patologia , Sobrevivência de Enxerto , Humanos , Fígado/ultraestrutura , Necrose , Período Pós-Operatório
8.
Transplant Proc ; 36(6): 1747-52, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15350468

RESUMO

BACKGROUND: Renal dysfunction remains the Achilles' heel of calcineurin inhibitor (CI)use. The purpose of this study was to assess our institutional, renal-sparing strategy using thymoglobulin (TMG) in recipients of orthotopic liver transplants. METHODS: We performed a retrospective analysis of data from 298 adult recipients who were transplanted between 1991 and 2002. The patients were divided into two groups: those induced with TMG (group 1) and those that were not treated with this agent (group 2). A subgroup analysis was performed of patients with baseline serum creatinine values above 1.5 mg/dL (group 1A received TMG; group 2A did not). All patients received tacrolimus or cyclosporine (CyA) maintenance immunosuppression. RESULTS: Indications and demographics were similar between the two groups. Although there was no difference in patient and graft survivals, there was a statistically significant benefit in the rejection-free graft survival at 1 year for group 1 (51% vs 39%; P =.02). Furthermore, serum creatinine at 6 months was lower for group 1, despite a similar baseline creatinine. Subgroup analysis for patients with baseline abnormal serum creatinines showed that group 1A displayed an improved rejection-free graft survival at 1 month but not at 1 year. CONCLUSIONS: Thymoglobulin induction therapy may allow a delay in the initiation of CI therapy without compromising patient and graft survival, while preventing early rejection, even among patients with baseline renal dysfunction.


Assuntos
Soro Antilinfocitário/uso terapêutico , Inibidores de Calcineurina , Transplante de Fígado/fisiologia , Adulto , Creatinina/sangue , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Testes de Função Renal , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo
9.
Transplant Proc ; 36(6): 1760-2, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15350471

RESUMO

BACKGROUND: Little is known about the effect of blood transfusions and leukoreduction on acute rejection in liver transplantation. The purpose of this study was to assess the impact of leukoreduction on the occurrence of early rejection episodes in liver transplantation. METHODS: In 1999, mandatory leukoreduction was implemented in our program. Data from 339 consecutive liver transplant recipients were analyzed with attention to the time period as a proxy for leukoreduction, the number of transfusions, the wait list status, the hepatitis B or C status, the recipient age, and the type of immunosuppression. RESULTS: Using an early (6-month) rejection-free graft survival model, we observed that introduction of leukoreduction was independently associated with fewer rejection episodes (P =.001). Despite the lower rejection rate, due to a regimen of tacrolimus and antithymocyte globulin, the effect of implementation of leukoreduction remained significant (P =.021). CONCLUSION: The use of leukoreduction is associated with fewer early rejections, irrespective of the type of immunosuppression. These data support an exploration of the immunomodulatory effect of leukoreduction.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Procedimentos de Redução de Leucócitos , Transplante de Fígado/imunologia , Intervalo Livre de Doença , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Humanos , Estudos Retrospectivos
10.
Transplant Proc ; 35(7): 2420-2, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14611976

RESUMO

AIM: To assess the incidence of urological complications and hematuria after adult kidney transplantation using the Lich-Gregoire (LG) versus the Taguchi (T) ureteral implantation technique. METHODS: We performed a retrospective analysis of 212 consecutive kidney transplants from our institution using an access database. RESULTS: Sixty four patients underwent ureteral implantation using the T technique, and the other 148, the LG implantation. Both groups were matched for donor/recipient characteristics and for cold/warm ischemia times. There were 23 urological complications in 17 patients. Twenty-seven patients developed complicated hematuria. The rates of urinary leak and ureteral stones were not different. There was a higher incidence of permanent ureteral strictures using the LG technique (P =.05). T technique was associated more frequently with hematuria, but there was no difference in the length of stay. CONCLUSIONS: We identified an increased incidence of permanent strictures with the LG technique. The rate of hematuria was higher in the T group. Both techniques can be used interchangeably with acceptable rates of urological complications. The simplicity of the T technique has made it the technique of choice in our institution.


Assuntos
Complicações Intraoperatórias/cirurgia , Transplante de Rim/efeitos adversos , Ureter/cirurgia , Doenças Urológicas/epidemiologia , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Doenças Urológicas/etiologia
11.
Transplant Proc ; 35(7): 2435-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14611980

RESUMO

AIM: Most technical complications after orthotopic liver transplantation (OLT) are related to the biliary tree. This report reviews the role of routine intraoperative placement of stents to reduce biliary complications. METHODS: We retrospectively analyzed 396 consecutive OLTs. We reviewed rates of biliary complications after hepaticojejunostomy (HJA) as well as following choledochocholedochostomy (CCA) groups: "experimental" group (routine intraoperative biliary stenting, last 10 months), "recent" control group (nonstented, previous 10 months), "historical" control group (prior to that period of time). RESULTS: All groups were matched for donor/recipient characteristics and for graft cold/warm ischemia time. The overall prevalence of biliary complications was 30.7% after CCA versus 35% after HJA. In the experimental group 21 patients had a 4.8% biliary complication rate compared to the recent control and historical groups, where biliary complication rates were 30% and 32.6%, respectively (P <.05). CONCLUSIONS: The intraoperative use of biliary stents is feasible and appears to decrease the rate of biliary complications. These results support the need for a prospective randomized trial.


Assuntos
Doenças da Vesícula Biliar/prevenção & controle , Vesícula Biliar/cirurgia , Transplante de Fígado/métodos , Coledocostomia , Seguimentos , Humanos , Jejuno/cirurgia , Fígado/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Fatores de Tempo
13.
Curr Pharm Des ; 7(9): 803-31, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375780

RESUMO

Retinoids (vitamin A and its analogs) exert profound effects on a wide variety of life processes, including morphogenesis and embryonic development. Several retinoids are also effective drugs for therapy of skin diseases and some types of cancer. However, the applicability of this class of compounds is limited by their teratogenic activity. A major question in retinoid toxicology has been the marked interspecies differences in the lowest teratogenic doses of 13-cis-retinoic acid and retinol. In addition, great attention has been drawn to the risk assessment of embryotoxicity resulting from excessive intake of vitamin A by pregnant women. The present review first gives an overview of the biochemistry, metabolism and mode of action of retinoids as well as their role in embryonic development. It then summarizes the results of recent studies on retinoid metabolism, toxicokinetics, and embryonic exposure and discusses how the available information provides explanation of the aforementioned interspecies variations. Finally, it presents some approaches for risk assessment of high vitamin A intake by humans based on various animal models and epidemiological studies.


Assuntos
Retinoides/metabolismo , Retinoides/toxicidade , Teratogênicos/metabolismo , Teratogênicos/toxicidade , Anormalidades Induzidas por Medicamentos/patologia , Animais , Feminino , Humanos , Troca Materno-Fetal , Gravidez , Retinoides/farmacocinética , Teratogênicos/farmacocinética
15.
Dermatology ; 200(1): 40-2, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10681612

RESUMO

BACKGROUND: The introduction of HIV-1 protease inhibitors into the treatment of patients infected with HIV-1 has had a major influence on clinical practice. However, the use of protease inhibitors is frequently associated with the development of resistance and several side effects and interactions with other drugs have been reported. OBSERVATIONS: We present the first pediatric patient with paronychia with pyogenic granuloma associated with the administration of the protease inhibitor indinavir. Clinical findings are discussed in view of a possible interference of indinavir with endogenous retinoid metabolism. CONCLUSION: Considerable evidence advocates the mediation of indinavir side effects by impaired oxidative metabolism of retinoic acid through the inhibition of cytochromes P450 3A by indinavir rather than by impaired formation of 9-cis-retinoic acid.


Assuntos
Granuloma Piogênico/induzido quimicamente , Inibidores da Protease de HIV/efeitos adversos , Indinavir/efeitos adversos , Paroniquia/induzido quimicamente , Dermatopatias/induzido quimicamente , Adolescente , Criança , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , Humanos , Indinavir/uso terapêutico , Masculino , Retinoides/metabolismo , Dedos do Pé
16.
Cancer Res ; 59(22): 5737-44, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10582693

RESUMO

Uterine leiomyomata are the main indication for a hysterectomy in the United States and occur in 25% of women >35 years. Because uterine leiomyomata can form when ovariectomized guinea pigs are exposed to estradiol and retinoic acids, we tested whether human leiomyomata had high levels of retinoic acids and related nuclear receptors. Compared with normal human myometrium, leiomyomata had 3- to 5-fold higher levels of peroxisome proliferator-activated receptor gamma (PPARgamma), retinoid X receptor alpha proteins, and all-trans retinoic acid, but only during the follicular phase of the menstrual cycle. 9-cis Retinoic acid was undetectable in either leiomyomata or myometrium. PPARgamma mRNA levels were lower in leiomyomata than myometrium, but only during the luteal phase of the cycle. A PPARgamma agonist, troglitazone, was given to guinea pigs along with estradiol and all-trans retinoic acid and produced the largest leiomyomata seen to date in this model. By contrast, no tumors formed when troglitazone was given alone or with estradiol or when troglitazone was given with estradiol and 9-cis retinoic acid. New therapies for human leiomyomata may emerge by combining antagonists for PPARgamma and retinoid X receptor alpha with selective estrogen receptor modulators.


Assuntos
Leiomiomatose/metabolismo , Miométrio/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Ácido Retinoico/metabolismo , Tiazolidinedionas , Fatores de Transcrição/metabolismo , Tretinoína/metabolismo , Neoplasias Uterinas/metabolismo , Alitretinoína , Animais , Carcinógenos , Cromanos , Implantes de Medicamento , Estradiol , Feminino , Cobaias , Humanos , Leiomiomatose/induzido quimicamente , Ciclo Menstrual , Miométrio/efeitos dos fármacos , Receptor alfa de Ácido Retinoico , Tiazóis , Troglitazona , Neoplasias Uterinas/induzido quimicamente
17.
Drug Metab Dispos ; 27(3): 317-21, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10064560

RESUMO

Retinaldehyde (RAL), a key intermediate in retinoid metabolism, acts as a retinoic acid (RA) precursor, but is also reduced to retinol (ROH), which can subsequently be esterified to retinyl esters, the storage form of vitamin A. Limited information is available on the metabolism of geometric isomers of RAL as well as on the transplacental distribution of their metabolites, including RA isomers. Such information would be very helpful for the assessment of the teratogenic potency of RAL isomers, as teratogenesis represents a major side effect of retinoid use in pharmacotherapy. In the present study we examined concentrations of retinoids in plasma, maternal tissues, and embryos of pregnant rats 2 h after a single oral dose (100 mg/kg body weight) of all-trans-, 13-cis-, or 9-cis-RAL on gestational day 13. The main findings of this study were the very similar patterns of retinoid metabolites (consisting of retinoids with mainly the all-trans-configuration) after administration of all-trans- and 13-cis-RAL, and the high concentrations of 9-cis-RA, 9,13-dicis-RA, and 9-cis-retinoyl-beta-D-glucuronide after dosing with 9-cis-RAL. In addition, all-trans-RA as a RAL metabolite reached the embryos to a much greater extent than any of its cis-isomers. The results are discussed in view of in vitro data on enzymes involved in the biotransformation of RAL isomers.


Assuntos
Prenhez/metabolismo , Retinaldeído/metabolismo , Retinoides/metabolismo , Animais , Feminino , Isomerismo , Gravidez , Ratos , Ratos Wistar
18.
J Med Primatol ; 27(6): 310-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10203012

RESUMO

To further define teratogenicity associated with 13-cis-retinoic acid (13-cis-RA) in the cynomolgus monkey, the drug was orally administered on three different treatment regimens. Experiment (Exp.) 1 (2.5 mg/kg/day, gestational day [GD] 12-27, n = 11) investigated the teratogenicity of a single daily dose of 13-cis-RA administered shortly after embryo implantation. Pharmacokinetic sampling was done to determine retinoid profiles on the first (GD12) and last (GD27) days of treatment. Exposure to 13-cis-RA during early organogenesis in Exp. 2 (2.5 mg/kg/day, GD20-27, and 2 x 2.5 mg/kg/day, GD28-30, n = 5) investigated the potential adverse effects of 13-cis-RA on the developing limb. The use of multiple doses of 13-cis-RA in Exp. 3 (2 x 2.5 mg/kg/day, GD26-27, n = 5) investigated the necessity of double dosing on the induction of retinoid embryopathy in the macaque. Malformations of retinoid target organs as well as embryolethality were most prevalent when single daily doses of 13-cis-RA were administered during pre- and early organogenesis in Exp. 1. Moreover, multiple doses on GD26-27 failed to induce any manifestation of abnormal development in Exp. 3. These results confirm that the lowest observed adverse effect level (LOAEL) in macaques is 2.5 rather than 5.0 times greater than that observed in human pregnancies. Exposure during forelimb development (GD20-30) in Exp. 2 was unsuccessful in inducing defects of this skeletal region, although defects in several retinoid target organs (i.e., cerebellum and internal ear) were present, indicating that a teratogenic threshold was achieved. Pharmacokinetic analysis of 13-cis-RA and its metabolites on GD12 and 27 in Exp. 1 showed considerable exposure to the administered drug and its 4-oxo-metabolite. In contrast, the exposure to all-trans-RA was negligible. The results support the use of a specific treatment schedule in early gestation in the macaque as the most appropriate model for characterizing the teratogenic potential of retinoids in humans.


Assuntos
Anormalidades Induzidas por Medicamentos , Feto/efeitos dos fármacos , Macaca fascicularis/embriologia , Prenhez/efeitos dos fármacos , Retinoides/toxicidade , Animais , Esquema de Medicação , Feminino , Macaca fascicularis/anormalidades , Gravidez , Retinoides/administração & dosagem
19.
Toxicol Appl Pharmacol ; 143(2): 436-44, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9144460

RESUMO

Earlier studies with etretinate and its metabolite acitretin suggested that area under the concentration-time curve (AUC) is the most suitable pharmacokinetic correlate to etretinate-induced teratogenesis. In an attempt to test this hypothesis with respect to the embryotoxic effects of all-trans-retinoic acid (all-trans-RA), we determined the embryotoxicity and plasma pharmacokinetics of all-trans-RA and its metabolites following administration of all-trans-RA to Wistar rats on Gestational Day (GD) 9, either subcutaneously (sc; dose levels 1, 3, or 5 mg/kg body mass) or orally (po; 5 mg/kg body mass). The 5 mg/kg dose of all-trans-RA was not embryotoxic when administered orally but led to high rates of embryolethality and skeletal defects following sc treatment. Determination of retinoids by HPLC showed that all-trans-RA reached similar maximum plasma concentrations (C(max)) after both dosing regimens, but its plasma AUC was ca. threefold higher after sc injection than po administration due to the slower uptake rate of the drug and its limited detoxification via beta-glucuronidation following sc injection. Furthermore, retinoid analysis in rat tissues (liver, kidney, duodenum, and jejunum), collected 1 hr after sc or po administration of 5 mg all-trans-RA/kg body mass on GD 9, confirmed that formation of all-trans-retinoyl-beta-glucuronide was much more extensive after po than after sc administration. Finally, linear regression analysis of either C(max). or AUC values of all-trans-RA in rat plasma and fetal abnormality rates showed that AUC values are better correlated with the embryotoxic outcome than C(max) [AUC-based correlation coefficient (r) > 0.90; C(max)-based r < 0.43]. Our findings establish the relevance of the AUC of all-trans-RA, and not its C(max), as the most appropriate pharmacokinetic marker of embryonic exposure and embryotoxic potency of all-trans-RA and stress the importance of the duration of exposure as a major determinant of embryotoxic outcome for retinoids.


Assuntos
Embrião de Mamíferos/metabolismo , Feto/metabolismo , Ceratolíticos/farmacocinética , Tretinoína/farmacocinética , Anormalidades Induzidas por Medicamentos/etiologia , Administração Oral , Animais , Área Sob a Curva , Osso e Ossos/anormalidades , Osso e Ossos/efeitos dos fármacos , Vias de Administração de Medicamentos , Embrião de Mamíferos/efeitos dos fármacos , Feminino , Feto/efeitos dos fármacos , Idade Gestacional , Injeções Subcutâneas , Ceratolíticos/administração & dosagem , Ceratolíticos/toxicidade , Modelos Lineares , Troca Materno-Fetal/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar , Distribuição Tecidual , Tretinoína/administração & dosagem , Tretinoína/toxicidade
20.
Breast Cancer Res Treat ; 43(1): 43-51, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9065598

RESUMO

A series of 80 female patients undergoing surgery for primary breast ductal infiltrating carcinoma not otherwise specified (NOS) was immunohistochemically studied in order to verify any relationships between Proliferating Cell Nuclear Antigen (PCNA) immunostaining, Heat Shock Protein 70 (HSP70) immunoreactivity, and several clinicopathological predictors. Positive PCNA scores (> 20% of strongly immunopositive malignant nuclei) were observed in neoplastic cells' nuclei in 13 tumors (16.25%) and were intimately associated with axillary nodal involvement (p = 0.0131), relatively high tumor grades (p = 0.0016), increased tumor size (p = 0.0312), and low or negative levels of estrogen receptors (p = 0.0323). HSP70 positive immunoexpression in malignant cells' cytoplasm (percentage of HSP70 immunoreactive cells > 10%) was detected in 33 samples (41.25%). It correlated significantly with presence of axillary lymph nodal metastases (p = 0.0033) and rather poor tumor differentiation (p = 0.0014), whereas an association of borderline statistical significance emerged between HSP70 immunoreactivity and high progesterone receptor status (p = 0.0637). PCNA positive immunostaining demonstrates the tumors' proliferative fraction and might be used as an indicator of increased malignant potential in breast cancer since it was associated with four adverse prognosticators. HSP70 immunodetection is a probable marker of the biological stress experienced by breast cancer cells, since it was related to relatively high tumor grades. Since both proteins may potentially predict disease outcome, their prognostic significance must be validated by direct relation to survival. A multivariate statistical analysis including the variables with which both proteins were associated will reveal any possible independent prognostic value of PCNA and HSP70 immunostaining in local, ductal invasive breast cancer NOS.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteínas de Choque Térmico/análise , Antígeno Nuclear de Célula em Proliferação/análise , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Prognóstico
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