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1.
Palliat Support Care ; 13(2): 145-55, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24183005

RESUMO

OBJECTIVE: When infants are at risk of being born at a very premature gestation (22-25 weeks), parents face important life-support decisions because of the high mortality for such infants. Concurrently, providers are challenged with providing parents a supportive environment within which to make these decisions. Practice guidelines for medical care of these infants and the principles of perinatal palliative care for families can be resources for providers, but there is limited research to bridge these medical and humanistic approaches to infant and family care. The purpose of this article is to describe how parents at risk of delivering their infant prior to 26 weeks gestation interpreted the quality of their interpersonal interactions with healthcare providers. METHODS: Directed content analysis was employed to perform secondary analysis of data from 54 parents (40 mothers and 14 fathers) from the previously coded theme "Quality of Interactions." These categorized data described parents' encounters, expectations, and experiences of interactions that occurred prenatally with care providers. For this analysis, Swanson's theory of caring was selected to guide analysis and to delineate parents' descriptions of caring and uncaring interactions. RESULTS: Parents' expectations for caring included: (a) respecting parents and believing in their capacity to make the best decisions for their family (maintaining belief); (b) understanding parents' experiences and their continued need to protect their infant (knowing); (c) physically and emotionally engaging with the parents (being with); (d) providing unbiased information describing all possibilities (enabling); and (e) helping parents navigate the system and creating a therapeutic environment for them in which to make decisions (doing for). SIGNIFICANCE OF RESULTS: Understanding parents' prenatal caring expectations through Swanson's theory gives deeper insights, aligning their expectations with the palliative care movement.


Assuntos
Aconselhamento , Lactente Extremamente Prematuro , Cuidados Paliativos , Pais/psicologia , Assistência Perinatal/métodos , Qualidade da Assistência à Saúde , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez
2.
Xenobiotica ; 44(3): 264-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23517558

RESUMO

1. A catheterized rat model was used to define the intestinal and hepatic components of oral bioavailability for an 11ß-HSD1 inhibitor, AMG 221. These data were integrated with standard in vivo metabolism studies to elucidate the components contributing to the oral disposition of a novel drug candidate. 2. Intestinal and hepatic extraction ratios of AMG 221 obtained using a five-catheter rat model were 0.56 and 0.32, respectively. Therefore, both intestinal and hepatic extraction contributed to the first-pass component of oral bioavailability. There was no evidence for significant gut extraction of systemically administered drug. 3. Mass balance data and in vivo metabolite characterization obtained after administration of [(14)C] AMG 221 to rat showed that AMG 221 was completely absorbed from the gut lumen following an oral dose, primarily excreted in urine and was almost completely metabolized prior to excretion. 4. Hepatic bioavailability (FH), measured in two animals at various time points after oral dose administration was somewhat variable but generally characterized by an initial reduction during the absorption phase followed by an increase during the elimination phase, consistent with hepatic distribution of AMG 221. 5. The five-catheter rat model afforded estimates of hepatic and intestinal contribution to oral bioavailability that were used with other data to define the preclinical ADME characteristics of a drug candidate.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Tiazóis/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Radioisótopos de Carbono/metabolismo , Estrutura Molecular , Ratos , Tiazóis/administração & dosagem , Tiazóis/química , Dispositivos de Acesso Vascular
3.
Pediatr Radiol ; 42(5): 536-43, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22033858

RESUMO

BACKGROUND: Thrombosis of fetal intracranial dural sinuses is a rare entity. A specific type of midline dural sinus thrombosis (DST) at the torcular Herophili with extension into the superior sagittal sinus (SSS) was initially seen on fetal US and was referred to fetal MRI for definite diagnosis and better delineation. OBJECTIVE: Retrospective comparison to medical literature of three cases, diagnosed at our institution, of midline fetal DST with MR imaging findings and clinical outcomes. MATERIALS AND METHODS: We reviewed MRI findings on T2-weighted images of our three cases of fetal midline DST and clinical outcomes of these fetuses and compared our findings to medical literature. The MR imaging and clinical findings of our cases extend over 6 years. They consist of three pregnant women, 31-39 years of age each with a single fetus, with fetal MR imaging performed at different gestational ages (GA). Case 1 the MR imaging was performed at 21 5/7 weeks' GA, case 2 at 24 and 33 4/7 weeks' GA, and case 3 at 22 and 25 weeks' GA. Postnatal MRI was performed in case 2 at 6 months of life and case 3 at 1 day of life. Clinical follow-up occurred during the last 6 years. RESULTS: In all of our cases, T2-W MR imaging demonstrated ballooned midline torcular Herophili with iso- to hypointense mass with or without focal eccentric area of greater hypointensity occupying the torcular Herophili with extension into the SSS. Case 3 had associated leptomeningeal dural vascular malformation overlying the left cerebral hemisphere with development of migrational disorder in the left cerebral hemisphere. Clinical outcome consisted of fetal demise in case 1, normal postnatal outcome in case 2 and severe brain damage with poor postnatal outcome in case 3. CONCLUSION: Our findings of large iso-hypointense thrombus with or without a focal eccentric area more hypointense to thrombus in a dilated torcular Herophili with extension into the SSS on T2-W images corresponds to the majority of cases of this rare type of DST in the medical literature.


Assuntos
Cavidades Cranianas/anormalidades , Doenças Fetais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal , Trombose dos Seios Intracranianos/diagnóstico , Adulto , Meios de Contraste , Feminino , Idade Gestacional , Humanos , Meglumina/análogos & derivados , Compostos Organometálicos , Gravidez , Estudos Retrospectivos
4.
Qual Health Res ; 22(9): 1232-46, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22745363

RESUMO

This study evaluated parents' and health care providers' (HCPs) descriptions of hope following counseling of parents at risk of delivering an extremely premature infant. Data came from a longitudinal multiple case study investigation that examined the decision making and support needs of 40 families and their providers. Semistructured interviews were conducted before and after delivery. Divergent viewpoints of hope were found between parents and many HCPs and were subsequently coded using content analysis. Parents relied on hope as an emotional motivator, whereas most HCPs described parents' notions of hope as out of touch with reality. Parents perceived that such divergent beliefs about the role of hope negatively shaped communicative interactions and reduced trust with some of their providers. A deeper understanding of how varying views of hope might shape communications will uncover future research questions and lead to theory-based interventions aimed at improving the process of discussing difficult news with parents.


Assuntos
Comunicação , Aconselhamento Diretivo/métodos , Lactente Extremamente Prematuro/psicologia , Educação de Pacientes como Assunto/métodos , Relações Profissional-Família , Percepção Social , Adulto , Tomada de Decisões , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Hospitais , Humanos , Recém-Nascido , Entrevista Psicológica , Estudos Longitudinais , Masculino , Grupo Associado , Pesquisa Qualitativa , Gravação em Fita , Revelação da Verdade
5.
J Perinat Neonatal Nurs ; 25(1): 52-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21311270

RESUMO

Most deaths of extremely premature infants occur in the perinatal period. Yet, little is known about how parents make life support decisions in such a short period of time. In the paper, how parents make life support decisions for extremely premature infants from the prenatal period through death from the perspectives of parents, nurses, and physicians is described. Five cases, comprised of five mothers, four neonatologists, three nurses, and one neonatal nurse practitioner, are drawn from a larger collective case study. Prenatal, postnatal and end-of-life interviews were conducted, and medical record data were obtained. In an analysis by two research team members, mothers were found to exhibit these characteristics: desire for and actual involvement in life support decisions, weighing pain, suffering and hope in decision making, and wanting everything done for their infants. All mothers received decision making help and support from partners and family, but relationships with providers were also important. Finally, external resources impacted parental decision making in several of the cases. By understanding what factors contribute to parents' decision making, providers may be better equipped to prepare and assist parents when making life support decisions for their extremely premature infants.


Assuntos
Atitude Frente a Morte , Tomada de Decisões , Recém-Nascido de Peso Extremamente Baixo ao Nascer/psicologia , Cuidados para Prolongar a Vida/psicologia , Pais/psicologia , Nascimento Prematuro/psicologia , Adulto , Feminino , Humanos , Recém-Nascido , Acontecimentos que Mudam a Vida , Masculino , Mães/psicologia , Enfermagem Neonatal/métodos , Pesquisa Metodológica em Enfermagem , Pais/educação , Gravidez , Nascimento Prematuro/enfermagem , Inquéritos e Questionários , Revelação da Verdade , Suspensão de Tratamento , Adulto Jovem
6.
Clin Kidney J ; 14(1): 167-173, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33564415

RESUMO

BACKGROUND: Previous studies have established an association between low birthweight (LBW) and future kidney disease, but few have explored the progression of kidney dysfunction through the pediatric years leading up through adolescence and young adulthood. METHODS: To better understand the temporal effects of birthweight on kidney disease progression, we conducted a retrospective cohort study comparing the glomerular filtration rate (GFR) between LBW (<2500 grams) and normal birthweight (NBW) infants who were admitted to the neonatal intensive care unit (NICU) at our institution from 1992 to 2006. RESULTS: Age at follow-up ranged 1-26 years old. GFR was found to be significantly lower in participants born with LBW than those born with NBW, with a mean difference of 5.5 mL/min/1.73m2 (P < 0.01). These differences were found in the adolescent and young adult age group over 9 years of age, specifically in the extremely low birthweight group (ELBW) whose birthweight was less than 1000 grams. CONCLUSIONS: We recommend screening for CKD in ELBW individuals starting at the age of 9 years old, regardless of their previous medical history.

7.
Drug Metab Dispos ; 38(1): 61-72, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19797607

RESUMO

The prediction of in vivo drug-drug interactions from in vitro enzyme inhibition parameters remains challenging, particularly when time-dependent inhibition occurs. This study was designed to examine the accuracy of in vitro-derived parameters for the prediction of inhibition of CYP3A by erythromycin (ERY). Chronically cannulated rats were used to estimate the reduction in in vivo and in vitro intrinsic clearance (CL(int)) of midazolam (MDZ) after single and multiple doses of ERY; in vitro recovery of CL(int) was determined at 1, 2, 3, and 4 days after discontinuation of ERY. Enzyme inhibition parameters (k(inact), K(I), and K(i)) of ERY were estimated in vitro by using untreated rat liver microsomes. In vivo enzyme kinetic analysis indicated that single and multiple doses of ERY (150 mg/kg i.v. infusion over 4 h) reduced MDZ CL(int) by reversible and irreversible mechanisms, respectively. CYP3A inactivation after multiple doses of ERY treatment reflected metabolic intermediate complex formation without a significant change in hepatic CYP3A2 mRNA. A physiologically based pharmacokinetic model of the interaction between ERY and MDZ predicted a 2.6-fold decrease in CYP3A activity after repeated ERY treatment using in vitro-estimated enzyme inhibition parameters and in vivo degradation half-life of the enzyme (20 + or - 6 h). The observed -fold decreases were 2.3-fold and 2.1-fold for the in vitro-estimated CYP3A activity and the in vivo CL(int), respectively. This study demonstrates that in vivo DDIs are predictable from in vitro data when the appropriate model and parameter estimates are available.


Assuntos
Inibidores do Citocromo P-450 CYP3A , Eritromicina/farmacologia , Algoritmos , Animais , Área Sob a Curva , Hidrocarboneto de Aril Hidroxilases/genética , Biocatálise/efeitos dos fármacos , Simulação por Computador , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas/fisiologia , Eritromicina/administração & dosagem , Eritromicina/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Cinética , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Proteínas de Membrana/genética , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Midazolam/análogos & derivados , Midazolam/sangue , Midazolam/metabolismo , Midazolam/farmacocinética , Modelos Biológicos , Ratos , Ratos Sprague-Dawley
8.
J Matern Fetal Neonatal Med ; 32(5): 820-825, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29103318

RESUMO

OBJECTIVE: To examine prospective parents' perceptions of management options and outcomes in the context of threatened periviable delivery, and the values they apply in making antenatal decisions during this period. STUDY DESIGN: Qualitative analysis of 46 antenatal interviews conducted at three tertiary-care hospitals with 54 prospective parents (40 pregnant women, 14 partners) who had received counseling for threatened periviable delivery (40 cases). RESULTS: Participants most often recalled being involved in resuscitation, cerclage, and delivery mode decisions. Over half (63.0%) desired a shared decision-making role. Most (85.2%) recalled hearing about morbidity and mortality, with many reiterating terms like "brain damage", "disability", and "handicap". The potential for disability influenced decision making to variable degrees. In describing what mattered most, participant spoke of giving their child a "fighting chance"; others voiced concerns about "best interest", a "healthy baby", "pain and suffering", and religious faith. CONCLUSIONS: Our findings underscore the importance of presenting clear information on disability and eliciting the factors that parents deem most important in making decisions about periviable birth.


Assuntos
Tomada de Decisões , Viabilidade Fetal , Pais/psicologia , Feminino , Humanos , Cuidados para Prolongar a Vida/psicologia , Masculino , Gravidez , Pesquisa Qualitativa
9.
Drug Metab Dispos ; 36(6): 1097-101, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18339815

RESUMO

Itraconazole (ITZ) is a substrate of CYP3A and both ITZ and hydroxyitraconazole (OH-ITZ), a major metabolite formed by CYP3A, are potent inhibitors of CYP3A. The concentration- and time-dependent changes in the hepatic availability (F(H)) of ITZ were evaluated in rats after oral doses of 5 and 40 mg/kg. Simultaneous blood samples were obtained from the aorta, portal vein, and hepatic vein for 24 h following duodenal ITZ administration, and concentrations of ITZ and OH-ITZ determined by LC/MS. During the absorption phase, the F(H) of ITZ increased from 0.2 to 1.0, reflecting the time course of hepatic CYP3A inhibition. A counterclockwise hysteresis was observed between ITZ concentrations entering the liver (C(IN,ITZ)) and F(H), whereas there was no time delay observed between the change in F(H) and the OH-ITZ concentrations entering the liver (C(IN,OH-ITZ)). The direct relationship between C(IN,OH-ITZ) and F(H) suggested that OH-ITZ was mainly responsible for the inhibition of CYP3A. A positive portal venous-aortic gradient for OH-ITZ was measured after duodenal administration of ITZ, indicating intestinal formation of OH-ITZ. The in vivo Ki for OH-ITZ (38 +/- 3 nM) was estimated from C(IN,OH-ITZ) versus F(H) of ITZ, and is similar to values obtained from inhibition of midazolam hydroxylation in CYP3A4 supersomes (Drug Metab Dispos 32:1121-1131, 2004). The data suggest that OH-ITZ, formed by intestinal CYP3A, controls the time course of hepatic CYP3A inhibition and is mainly responsible for the observed increase in F(H) of ITZ.


Assuntos
Antifúngicos/farmacocinética , Inibidores do Citocromo P-450 CYP3A , Mucosa Intestinal/metabolismo , Itraconazol/análogos & derivados , Itraconazol/farmacocinética , Fígado/metabolismo , Animais , Antifúngicos/sangue , Disponibilidade Biológica , Itraconazol/sangue , Itraconazol/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
10.
Am J Kidney Dis ; 45(4): 758-61, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15806479

RESUMO

Despite clinical and experimental data suggesting a direct relationship between antineutrophil cytoplasmic antibodies (ANCAs) and disease activity in patients with microscopic polyangiitis (MPA), the causal relationship between perinuclear ANCAs specific for myeloperoxidase (MPO-ANCA) and disease manifestations has been controversial. We describe the case of a woman with a history of pulmonary-renal syndrome caused by MPA whose disease became clinically and serologically active during pregnancy. Forty-eight hours after delivery, the newborn developed pulmonary hemorrhage and abnormalities in renal function. The newborn's cord blood showed an immunoglobulin G MPO-ANCA level identical to that of the mother's serum, indicating passive transfer of the antibody to the neonate. Our findings represent the first human model supporting the interpretation that MPO-ANCAs were immunopathogenic.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/imunologia , Imunidade Materno-Adquirida , Isoanticorpos/imunologia , Nefropatias/congênito , Pneumopatias/congênito , Complicações na Gravidez/imunologia , Vasculite/congênito , Adulto , Autoantígenos/imunologia , Cesárea , Dispneia/etiologia , Emergências , Feminino , Sangue Fetal/imunologia , Glomerulonefrite/imunologia , Hemorragia/congênito , Hemorragia/imunologia , Humanos , Recém-Nascido , Nefropatias/imunologia , Pneumopatias/imunologia , Troca Materno-Fetal , Peroxidase/imunologia , Gravidez , Síndrome , Vasculite/imunologia
11.
Shock ; 19(4): 352-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12688547

RESUMO

We have previously shown that systemic infusion of the bacterial toxins Staphylococcal enterotoxin B (SEB) and endotoxin (LPS) induces hepatic dysfunction as measured by decreased biliary indocyanine green (ICG) excretion. In this study, we compare the effects of these bacterial toxins after infusion into the portal and systemic circulation and directly measure biliary bile acid excretion as a measure of cholestasis. We hypothesized that bacterial toxins infused into the portal vein would induce greater hepatic dysfunction than toxins infused into the systemic circulation. Using a chronically catheterized rat model, biliary bile acid excretion was directly measured after infusion of LPS at 10 and 100 microg/kg with and without 50 microg/kg SEB into the portal vein (IPV) or inferior vena cava (IV) at baseline, and at 6 and 24 h. We found that when LPS was infused alone, only IPV administration caused a significant decrease in bile acid excretion at 6 h. There was no change in bile acid excretion after IV administration of LPS. In contrast, when the combination of LPS and SEB was infused, both IV and IPV administration significantly decreased bile acid excretion at 6 and 24 h. At 6 h post-LPS and -SEB administration, the decrease in bile acid excretion was significantly greater after IPV than IV administration. There was no site-specific difference in IFN-gamma release after infusion of toxins. However, peak TNFalpha release was decreased in IPV-infused rats [10 microg/kg (P < 0.05) or 100 microg/kg (P = ns) LPS with SEB] compared with the same doses in IV-infused rats. These data question the role of systemic TNF-alpha and IFN-gamma in regulating hepatic dysfunction and suggest a differential functional response of the liver to systemic and gut-derived septic events. This study also further explains the frequent development of liver dysfunction in patients with sepsis, multisystem organ failure, and other diseases with altered intestinal permeability.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Endotoxinas/toxicidade , Enterotoxinas/toxicidade , Animais , Bile/química , Ácidos e Sais Biliares/análise , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/metabolismo , Endotoxinas/administração & dosagem , Enterotoxinas/administração & dosagem , Injeções Intravenosas , Masculino , Veia Porta , Ratos , Ratos Sprague-Dawley , Veia Cava Inferior
12.
Shock ; 17(4): 312-5, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11954833

RESUMO

The mechanism of liver injury in endotoxemia is unclear. Previous studies have shown that splenectomy protects the liver from endotoxin-induced injury. The purpose of this study was to determine the relationship of TNFalpha and IFNgamma release and endotoxin-induced liver injury in splenectomized and nonsplenectomized rats. Splenectomized and nonsplenectomized (Sham) rats with chronic catheters in the aorta and inferior vena cava (IVC) were parenterally infused with 10 to 5000 microg/kg endotoxin. TNFalpha, IFNgamma, and alanine aminotransferase (ALT), a marker of hepatocellular damage, were measured in aortic blood. Compared to sham controls, splenectomized animals demonstrated significantly reduced endotoxin-induced ALT concentrations at endotoxin doses >10 microg/kg. Peak endotoxin-induced TNFalpha concentrations were not significantly different between the splenectomized and sham groups. In contrast, peak endotoxin-induced IFNgamma concentrations were significantly decreased in the splenectomized group. These data suggest a relationship between endotoxin-induced IFNgamma and liver injury. We speculate that the spleen contributes to the endotoxin-induced liver injury by modulating release of IFNgamma.


Assuntos
Endotoxinas/toxicidade , Interferon gama/biossíntese , Fígado/efeitos dos fármacos , Fígado/lesões , Baço/fisiologia , Alanina Transaminase/sangue , Animais , Interferon gama/sangue , Fígado/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Esplenectomia , Fator de Necrose Tumoral alfa/biossíntese
13.
Pediatrics ; 116(6): 1466-73, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16322172

RESUMO

OBJECTIVE: No uniform method for calculating growth velocity (GV) (grams per kilogram per day) among extremely low birth weight (ELBW) infants has been reported. Because the calculation of actual GV is so labor intensive, investigators have estimated GV with varying approaches, making comparisons across studies difficult. This study compares the accuracy of 3 mathematical methods used for estimating average GV, namely, 2-point models using the difference between weights at 2 time points divided by time and weight (either birth weight [BW] or average weight), linear regression models that are normalized for either BW or average weight, and an exponential model. The accuracy of all models was compared with actual GVs calculated from daily weight measures for a group of ELBW infants. METHODS: Actual GVs were calculated from daily weights for 83 ELBW infants admitted to the special care nursery and were compared with estimated GVs from each of the 5 models for the same infants. RESULTS: The exponential model, using weights from 2 time points, ie, GV = [1000 x ln(Wn/W1)]/(Dn-D1), was extremely accurate, with mean absolute errors of 0.02% to 0.10%. The 2-point and linear models were highly inaccurate when BW was used in the denominator, with mean absolute errors of 50.3% to 96.4%. The 2-point and linear models were fairly accurate when average weight was used in the denominator, with mean absolute errors of 0.1% to 8.97%. Additional analyses showed that the accuracy of the 2-point and linear model estimates was affected significantly by the combination of BW, length of stay, and chronic lung disease, whereas the exponential model was not affected by these combined factors. CONCLUSIONS: GV estimates calculated with 3 commonly used models varied widely, compared with actual GVs; however, the exponential model estimates were extremely accurate. The exponential model provides the accuracy and ease of use that are lacking in current methods applied to infant growth research.


Assuntos
Antropometria , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Humanos , Recém-Nascido , Modelos Teóricos
14.
Pediatr Nephrol ; 17(8): 609-11, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12185466

RESUMO

A 10-week-old female infant developed hypertension. The elevated blood pressure was associated with metabolic alkalosis and urinary chloride wastage. The family history was unremarkable. Her urinalysis, blood urea nitrogen (BUN), and serum creatinine concentrations were all normal. A renal ultrasound was normal. A technetium-99m diethylenetriaminopentoacetic acid (DTPA) renal scan with captopril showed normal blood flow bilaterally. The head ultrasound and echocardiogram were normal. Blood epinephrine, norepinephrine, catecholamines, thyroxine, and steroid levels were also normal. Treatment with various combinations of labetalol, hydralazine, captopril, methyldopa, nifedipine, and spironolactone, all at high doses, failed to control the elevated blood pressure. Serum aldosterone level and peripheral plasma renin activity were low. The lack of therapeutic response to spironolactone, with a good response to amiloride and recurrence of hypertension and metabolic alkalosis after amiloride cessation that was subsequently treated with amiloride, established the diagnosis of Liddle syndrome. To our knowledge, this is the youngest patient with Liddle syndrome that has been reported in the literature.


Assuntos
Alcalose/patologia , Insuficiência de Crescimento/patologia , Hipertensão/patologia , Hipopotassemia/patologia , Nefropatias/patologia , Alcalose/tratamento farmacológico , Amilorida/uso terapêutico , Pressão Sanguínea/fisiologia , Diuréticos/uso terapêutico , Eletrólitos/metabolismo , Insuficiência de Crescimento/tratamento farmacológico , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipopotassemia/tratamento farmacológico , Recém-Nascido , Nefropatias/diagnóstico por imagem , Nefropatias/tratamento farmacológico , Testes de Função Renal , Compostos Radiofarmacêuticos/uso terapêutico , Espironolactona/uso terapêutico , Síndrome , Pentetato de Tecnécio Tc 99m/uso terapêutico , Ultrassonografia
15.
Crit Care Med ; 30(11): 2509-14, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12441762

RESUMO

OBJECTIVE: To determine whether endotoxin-induced hyperlactatemia in hemodynamically stable animals is due to increased lactate production or decreased lactate clearance by measuring lactate turnover rate in the vascular compartment (LTRvc). DESIGN: Prospective, controlled trial. SETTING: Research laboratory in a university hospital. SUBJECTS: Male Sprague-Dawley rats weighing 275-425 g with chronic vascular catheters. INTERVENTIONS: Chronically catheterized rats were treated with 6 microg/kg endotoxin or saline. LTRvc was determined from the specific activity of carbon-14 [14C]lactate in aortic blood during a constant infusion of [14C]lactate into the inferior vena cava. The role of the splanchnic organs in lipopolysaccharide-induced alterations in LTRvc was determined from the splanchnic first-pass clearance of [14C]lactate infused into the superior mesenteric artery and direct measurements of blood lactate concentration gradients across the splanchnic organs. MEASUREMENTS AND MAIN RESULTS: Despite a 260% increase in lactate concentrations after lipopolysaccharide treatment, the specific activity of [14C]lactate and the LTRvc did not change, indicating that lipopolysaccharide-induced hyperlactatemia is caused by decreased lactate clearance from the vascular compartment rather than increased lactate flux into the vascular compartment. In contrast, lactate clearance by the splanchnic system was increased. The specific activity of [14C]lactate in aortic blood decreased 33% after lipopolysaccharide treatment when the [14C]lactate was infused into the superior mesenteric artery, indicating increased first-pass clearance of [14C]lactate by the splanchnic organs. Furthermore, the hepatic venous-aortic concentration gradient of lactate became increasingly negative after lipopolysaccharide treatment, indicating increased vascular extraction of lactate by the splanchnic system (0.07 +/- 0.07 micromol/mL vs. -0.34 +/- 0.14 micromol/mL). CONCLUSIONS: Lipopolysaccharide-induced hyperlactatemia in hemodynamically stable rats is caused by a net decrease in lactate clearance from the vascular compartment despite the fact that the clearance of lactate by the splanchnic system remains intact.


Assuntos
Acidose Láctica/fisiopatologia , Lactatos/sangue , Sepse/fisiopatologia , Acidose Láctica/sangue , Acidose Láctica/etiologia , Análise de Variância , Animais , Hemodinâmica , Lipopolissacarídeos , Fígado/metabolismo , Masculino , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley , Sepse/sangue , Sepse/complicações , Circulação Esplâncnica/fisiologia
16.
Crit Care Med ; 31(4): 1154-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12682487

RESUMO

OBJECTIVE: To determine the effect of chronic exposure to endotoxin (lipopolysaccharide) and Staphylococcal enterotoxin B on hepatic injury and function. DESIGN: Prospective, controlled trial. SETTING: Research laboratory in a university hospital. SUBJECTS: Male Sprague-Dawley rats weighing 325-350 g with chronic vascular and bile catheters. INTERVENTIONS: Chronically catheterized rats were treated daily with saline, 50 microg/kg Staphylococcal enterotoxin B alone, 1000 microg/kg lipopolysaccharide alone, 1000 microg/kg lipopolysaccharide with 50 microg/kg Staphylococcal enterotoxin B, or 100 microg/kg lipopolysaccharide with 50 microg/kg Staphylococcal enterotoxin B for 10 days. Serum and biliary measures of hepatic injury and dysfunction were measured before and then 6 hrs and 1, 2, 3, 7, and 10 days after the start of treatment. The animals were killed at 10 days and the livers examined histologically. MEASUREMENTS AND MAIN RESULTS: Mean rates of bile flow, biliary indocyanine green excretion, and bile acid flux were significantly decreased immediately after treatment (6 hr, 1 and 2 days) and then at 10 days. Increases in biliary and serum gamma-glutamyltransferase and serum bile acids also occurred in a similar bimodal pattern. Animals treated with lipopolysaccharide or Staphylococcal enterotoxin B alone became tolerant and did not develop the bimodal pattern of hepatic dysfunction. Histologic examination of the liver at 10 days revealed periportal inflammation and fibrosis. CONCLUSIONS: The combination of lipopolysaccharide and Staphylococcal enterotoxin B leads to late liver injury, whereas either toxin alone does not. These data may explain the frequent development of liver dysfunction in patients exposed to multiple bacterial toxins such as in sepsis, multiple-system organ failure, and other diseases with altered intestinal permeability.


Assuntos
Enterotoxinas/administração & dosagem , Lipopolissacarídeos/administração & dosagem , Hepatopatias/fisiopatologia , Fígado/fisiopatologia , Sepse/fisiopatologia , Staphylococcus aureus , Superantígenos/administração & dosagem , Alanina Transaminase/sangue , Animais , Bile/fisiologia , Ácidos e Sais Biliares/sangue , Escherichia coli , Verde de Indocianina , Infusões Intravenosas , Interferon gama/sangue , Hepatopatias/etiologia , Testes de Função Hepática , Masculino , Insuficiência de Múltiplos Órgãos/fisiopatologia , Ratos , Ratos Sprague-Dawley , Sepse/complicações , Fator de Necrose Tumoral alfa/análise , gama-Glutamiltransferase/análise
17.
Drug Metab Dispos ; 32(11): 1325-30, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15319324

RESUMO

The purpose of this investigation was to examine the effects of surgery and anesthesia on in vivo CYP3A activity and portal venous blood flow. Midazolam, a CYP3A probe for both rats and humans, was administered orally (2.7 mg), intravenously (0.57 mg), or via the portal vein (0.57 mg) to rats 4 h after anesthesia with ketamine/xylazine and surgery for placement of indwelling vascular and duodenal catheters and 3 days after surgery (chronic). The systemic clearance of midazolam was 51 +/- 4 ml/min/kg in the chronic animals, and this was significantly decreased (29 +/- 1 ml/min/kg, P = 0.024) in acute rats studied 4 to 6 h after anesthesia and surgery. The hepatic availability (FH), directly determined from the aortic and hepatic venous concentration gradient, was significantly higher in the acute animals (0.57 +/- 0.05) compared with the chronic animals (0.33 +/- 0.07, P = 0.001). Hepatic availability was determined using a classical approach in which FH was calculated from the area under the plasma concentration versus time curve ratio after portal venous or intravenous administration. FH was higher in the acute rats (0.48) compared with the chronic animals (0.27 +/- 0.03). Portal venous blood flow was significantly lower in the acute animals (5.0 +/- 0.4 ml/min/100 g body weight) compared with the chronic animals (9.1 +/- 0.9 ml/min/100 g body weight, P = 0.015). The effect of surgery and anesthesia was confirmed using the indicator dye dilution method after infusion of [14C]polyethylene glycol 4000 into the superior mesenteric artery. Our data suggest that anesthesia and surgery decreases both hepatic CYP3A activity and hepatic blood flow in rats. Studies performed in rats within 3 days of surgery and anesthesia are conducted under nonphysiologic conditions and therefore provide inaccurate assessment of drug disposition, in particular, clearance and bioavailability.


Assuntos
Anestésicos/farmacologia , Hidrocarboneto de Aril Hidroxilases/metabolismo , Cateterismo , Oxirredutases N-Desmetilantes/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Citocromo P-450 CYP3A , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Masculino , Oxirredutases N-Desmetilantes/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley
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