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1.
Br J Surg ; 97(3): 420-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20101595

RESUMO

BACKGROUND: This study compared adhesion reformation after open and laparoscopic adhesiolysis in a rat model. METHODS: Adhesions were induced by surgically creating ischaemic buttons on the peritoneal side wall. After 7 days the animals underwent laparoscopy with carbon dioxide insufflation or laparotomy to score and lyse adhesions. Peritoneal tissue and fluid were collected after 24 h in a subset of animals, and adhesion reformation was scored 7 days after lysis in the remainder. Tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI) 1, transforming growth factor (TGF) beta1 and tumour necrosis factor (TNF) alpha mRNA, and total fibrinolytic activity were assessed. The abdomen of non-operated animals was insufflated for 7, 15 or 30 min with carbon dioxide, after which tPA and PAI-1 mRNA and total fibrinolytic activity were measured. RESULTS: Animals that underwent open adhesiolysis had 60 per cent fewer reformed adhesions than the laparoscopic adhesiolysis group (P < 0.001). There were no differences in tPA activity or tPA, PAI-1 and TNF-alpha mRNA between groups, but TGF-beta1 mRNA levels were significantly increased in the open group. Carbon dioxide insufflation did not affect peritoneal tPA activity. CONCLUSION: Open adhesiolysis may be more beneficial in minimizing adhesion reformation in the management of adhesion-related complications.


Assuntos
Laparoscopia/métodos , Aderências Teciduais/cirurgia , Animais , Dióxido de Carbono/farmacologia , Insuflação , Masculino , Fibrose Peritoneal/etiologia , Fibrose Peritoneal/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Prevenção Secundária , Aderências Teciduais/prevenção & controle , Ativador de Plasminogênio Tecidual/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
2.
Cephalalgia ; 30(3): 260-71, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19732075

RESUMO

A novel approach to the treatment of chronic migraine headaches based on neurostimulation of both occipital and supraorbital nerves was developed and reduced to clinical practice in a series of patients with headaches unresponsive to currently available therapies. Following positive trials, seven patients with chronic migraine and refractory chronic migraine headaches had permanent combined occipital nerve-supraorbital nerve neurostimulation systems implanted. The relative responses to two stimulation programs were evaluated: one that stimulated only the occipital leads and one that stimulated both the occipital and supraorbital leads together. With follow-up ranging from 1 to 35 months all patients reported a full therapeutic response but only to combined supraorbital-occipital neurostimulation. Occipital nerve stimulation alone provided a markedly inferior and inadequate response. Combined occipital nerve-supraorbital nerve neurostimulation systems may provide effective treatment for patients with chronic migraine and refractory chronic migraine headaches. For patients with chronic migraine headaches the response to combined systems appears to be substantially better than occipital nerve stimulation alone.


Assuntos
Terapia por Estimulação Elétrica/métodos , Transtornos da Cefaleia/terapia , Enxaqueca com Aura/terapia , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço/inervação , Lobo Occipital/fisiopatologia , Órbita/inervação , Satisfação do Paciente , Resultado do Tratamento , Adulto Jovem
3.
Surg Endosc ; 21(10): 1790-5, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17356938

RESUMO

BACKGROUND: Up to 94% of patients experience fibrous adhesions after abdominal surgery, and a significant number of these patients require a second operation for open or laparoscopic lysis of adhesions (LOA). The authors have previously shown that inhibition of the binding of tachykinin ligands to the neurokinin 1 receptor (NK-1R) using the neurokinin 1 receptor antagonist (NK-1RA) CJ-12,255 decreases primary adhesion formation and upregulates the peritoneal fibrinolytic system in a rat model. Whereas most studies have focused on the prevention of primary adhesions, few have addressed adhesion reformation after LOA. This study aimed to determine the effects of NK-1RA administration on adhesion reformation and peritoneal fibrinolytic activity after laparoscopic LOA. METHODS: Adhesions were induced in 31 rats using our previously described ischemic button model. The rats underwent laparoscopy 7 days later, during which adhesions were scored and lysed followed by administration of the NK-1RA or saline. Then 7 days after LOA, 23 rats were killed and adhesions were scored. Eight rats also were killed 24 h after the LOA to obtain peritoneal tissue and fluid, which were analyzed for tissue plasminogen activator (tPA) mRNA expression and peritoneal fibrinolytic activity by reverse transcriptase-polymerase chain reaction (RT-PCR) and bioassay, respectively. RESULTS: At laparoscopy, 79% +/- 3% of the buttons formed adhesions. In the saline-administered control animals, 42% +/- 3.2% of the buttons reformed adhesions after LOA (p < 0.05), whereas in the animals that received the NK-1RA, 18.2% +/- 3.5% of the buttons reformed adhesions (p < 0.05). As compared with control animals, NK-1RA administration increased tPA mRNA levels by 38% and fibrinolytic activity sixfold (p < 0.05; 7.0 +/- 2.1 U/ml vs 1.2 +/- 0.54 U/ml). CONCLUSIONS: When administered during laparoscopic LOA, an NK-1RA significantly upregulates peritoneal fibrinolytic activity and decreases adhesion reformation.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Laparoscopia , Antagonistas dos Receptores de Neurocinina-1 , Aderências Teciduais/prevenção & controle , Aderências Teciduais/cirurgia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar , Recidiva
4.
Toxicol Sci ; 89(1): 296-303, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16237190

RESUMO

Using both in vivo (inhalation) and in vitro (cell culture) studies, we previously reported that p-aramid respirable fibers (RFP--defined as respirable-sized fiber-shaped particulates) are biodegraded in lungs and lung cells of rats following exposures. The current studies were undertaken to determine whether shortening mechanisms of p-aramid RFP biodegradability are also operative in human lung cells. Cultures of human A549 lung epithelial cells (A549), primary alveolar macrophages (HBAL) (collected via bronchoalveolar lavage [BAL]) from volunteers), and co-cultures (Co) of the A549 and HBAL were incubated with p-aramid RFP for either 1 h, 1 day, or 1 week to assess RFP shortening. Lengths of RFP were measured using scanning electron microscopy (SEM) following fixation, digestion of culture tissue components, and processing. Similar to findings using rat lung cells, only slight RFP shortening was measured in A549 cultures at 1-day and 1-week post-incubation. More importantly, in HBAL and Co groups, greater transverse cleavage of p-aramid RFP was measured at 1-day and 1-week postexposure compared to 1-h HBAL or Co groups, or in any A549 groups. In contrast, cellulose RFP, a biopersistent reference control fiber, were not measurably shortened under similar circumstances. Second, p-aramid RFP were incubated either with phosphate-buffered saline (PBS), or acellular BAL fluids from human volunteers or rats and processed for SEM analysis of RFP lengths. Mean lengths of p-aramid RFP incubated with human or rat BAL fluids were substantially decreased compared to PBS. Similar to our findings with rat lung cells, components of human lung fluids coat the p-aramid RFP as a prerequisite for subsequent enzymatic cleavage by human phagocytic lung cells and this finding reinforces the concept that inhaled p-aramid RFP are likely to be biodegradable in the lungs of humans.


Assuntos
Células Epiteliais/metabolismo , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Polímeros/farmacocinética , Administração por Inalação , Adolescente , Adulto , Animais , Biodegradação Ambiental , Biotransformação , Lavagem Broncoalveolar , Linhagem Celular , Celulose/química , Celulose/farmacocinética , Celulose/ultraestrutura , Técnicas de Cocultura , Células Epiteliais/citologia , Células Epiteliais/ultraestrutura , Feminino , Humanos , Pulmão/citologia , Macrófagos Alveolares/citologia , Macrófagos Alveolares/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polímeros/química , Ratos
5.
Part Fibre Toxicol ; 3: 3, 2006 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-16438714

RESUMO

The aim of this study was to evaluate the acute lung toxicity in rats of intratracheally instilled TiO2 particles that have been substantially encapsulated with pyrogenically deposited, amorphous silica. Groups of rats were intratracheally instilled either with doses of 1 or 5 mg/kg of hydrophilic Pigment A TiO2 particles or doses of 1 or 5 mg/kg of the following control or particle-types: 1) R-100 TiO2 particles (hydrophilic in nature); 2) quartz particles, 3) carbonyl iron particles. Phosphate-buffered saline (PBS) instilled rats served as additional controls. Following exposures, the lungs of PBS and particle-exposed rats were evaluated for bronchoalveolar lavage (BAL) fluid inflammatory markers, cell proliferation, and by histopathology at post-instillation time points of 24 hrs, 1 week, 1 month and 3 months. The bronchoalveolar lavage results demonstrated that lung exposures to quartz particles, at both concentrations but particularly at the higher dose, produced significant increases vs. controls in pulmonary inflammation and cytotoxicity indices. Exposures to Pigment A or R-100 TiO2 particles produced transient inflammatory and cell injury effects at 24 hours postexposure (pe), but these effects were not sustained when compared to quartz-related effects. Exposures to carbonyl iron particles or PBS resulted only in minor, short-term and reversible lung inflammation, likely related to the effects of the instillation procedure. Histopathological analyses of lung tissues revealed that pulmonary exposures to Pigment A TiO2 particles produced minor inflammation at 24 hours postexposure and these effects were not significantly different from exposures to R-100 or carbonyl iron particles. Pigment A-exposed lung tissue sections appeared normal at 1 and 3 months postexposure. In contrast, pulmonary exposures to quartz particles in rats produced a dose-dependent lung inflammatory response characterized by neutrophils and foamy (lipid-containing) alveolar macrophage accumulation as well as evidence of early lung tissue thickening consistent with the development of pulmonary fibrosis. Based on our results, we conclude the following: 1) Pulmonary instillation exposures to Pigment A TiO2 particles at 5 mg/kg produced a transient lung inflammatory response which was not different from the lung response to R-100 TiO2 particles or carbonyl iron particles; 2) the response to Pigment A was substantially less active in terms of inflammation, cytotoxicity, and fibrogenic effects than the positive control particle-type, quartz particles. Thus, based on the findings of this study, we would expect that inhaled Pigment A TiO2 particles would have a low risk potential for producing adverse pulmonary health effects.

6.
J Am Coll Cardiol ; 17(1): 167-73, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1987222

RESUMO

The echocardiographic studies and clinical course of 27 fetuses (mean gestational age 26.9 weeks) diagnosed in utero with tricuspid valve disease and significant tricuspid regurgitation were reviewed. The diagnosis of Ebstein's anomaly was made in 17 of the fetuses, 7 had tricuspid valve dysplasia with poorly developed but normally attached leaflets and 2 had an unguarded tricuspid valve orifice with little or no identifiable tricuspid tissue. One fetus was excluded from data analysis because a more complex heart lesion was documented at autopsy. All fetuses had massive right atrial dilation and most who were serially studied had progressive right-sided cardiomegaly. Hydrops fetalis was found in six cases and atrial flutter in five. Associated cardiac lesions included pulmonary stenosis in five cases and pulmonary atresia in six. Four fetuses with normal forward pulmonary artery flow at the initial examination were found at subsequent study to have retrograde pulmonary artery and ductal flow in association with the development of pulmonary stenosis (n = 1) and pulmonary atresia (n = 3). On review of the clinical course of the 23 fetuses (excluding 3 with elective abortion), 48% of the fetuses died in utero and 35% who were liveborn died despite vigorous medical and, when necessary, surgical management, many of whom had severe congestive heart failure. Of the four infants who survived the neonatal period, three had a benign neonatal course, all of whom were diagnosed with mild to moderate Ebstein's anomaly; only one had pulmonary outflow obstruction. An additional finding at autopsy was significant lung hypoplasia documented in 10 of 19 autopsy reports.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anomalia de Ebstein/diagnóstico por imagem , Ecocardiografia , Doenças Fetais/diagnóstico por imagem , Coração Fetal/diagnóstico por imagem , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/anormalidades , Ultrassonografia Pré-Natal , Anomalia de Ebstein/mortalidade , Feminino , Doenças Fetais/mortalidade , Humanos , Gravidez , Estudos Retrospectivos , Insuficiência da Valva Tricúspide/mortalidade
7.
J Am Coll Cardiol ; 8(2): 391-5, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2942595

RESUMO

With the combined use of two-dimensional ultrasound and Doppler echocardiography, noninvasive examination of the human fetal heart and circulation has recently become possible. These techniques were employed to investigate diastolic atrioventricular valve flow in the fetal heart in 120 fetuses studied between 17 and 42 weeks of gestation. Two-dimensional ultrasound was used to examine fetal and intrauterine anatomy, and estimates of gestational age were made based on biparietal diameters and femur lengths. Doppler echocardiography was performed with a 3.5 or 5 MHz Doppler sector scanner. Flow velocity patterns were obtained through the tricuspid and mitral valves during diastole. Peak flow velocity during late diastole or atrial contraction (A) was compared with peak flow velocity during early diastole (E) in four groups of fetuses: Group 1, 17 to 24 weeks of gestation; Group 2, 25 to 30 weeks; Group 3, 31 to 36 weeks; and Group 4, 37 to 42 weeks. The ratio of A to E decreased significantly as gestational age advanced, from 1.56 +/- 0.06 (+/- SE) to 1.22 +/- 0.03 across the tricuspid valve (p less than 0.001) and from 1.55 +/- 0.04 to 1.22 +/- 0.06 across the mitral valve (p less than 0.001). In tricuspid valve measurements, peak flow velocity during early diastole increased from 26.3 +/- 2.0 cm/s in Group 1 to 36.5 +/- 1.7 cm/s in Group 4 (p less than 0.001), whereas peak flow velocity during atrial contraction did not change.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Coração Fetal/fisiologia , Velocidade do Fluxo Sanguíneo , Diástole , Ecocardiografia , Feminino , Coração Fetal/anatomia & histologia , Idade Gestacional , Ventrículos do Coração/embriologia , Humanos , Valva Mitral/embriologia , Valva Mitral/fisiologia , Gravidez , Reologia , Valva Tricúspide/embriologia , Valva Tricúspide/fisiologia , Função Ventricular
8.
Toxicol Sci ; 88(2): 514-24, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16177240

RESUMO

Most pigment-grade titanium dioxide (TiO(2)) samples that have been tested in pulmonary toxicity tests have been of a generic variety-i.e., generally either uncoated particles or TiO(2) particles containing slightly hydrophilic surface treatments/coatings (i.e., base TiO(2)). The objectives of these studies were to assess in rats, the pulmonary toxicity of inhaled or intratracheally instilled TiO(2) particle formulations with various surface treatments, ranging from 0-6% alumina (Al(2)O(3)) or alumina and 0-11% amorphous silica (SiO(2)). The pulmonary effects induced by TiO(2) particles with different surface treatments were compared to reference base TiO(2) particles and controls. In the first study, groups of rats were exposed to high exposure (dose) concentrations of TiO(2) particle formulations for 4 weeks at aerosol concentrations ranging from 1130-1300 mg/m(3) and lung tissues were evaluated by histopathology immediately after exposure, as well as at 2 weeks and 3, 6, and 12 months postexposure. In the second study, groups of rats were intratracheally instilled with nearly identical TiO(2) particle formulations (when compared to the inhalation study) at doses of 2 and 10 mg/kg. Subsequently, the lungs of saline-instilled and TiO(2)-exposed rats were assessed using both bronchoalveolar (BAL) biomarkers and by histopathology/cell proliferation assessment of lung tissues at 24 h, 1 week, 1 and 3 months postexposure. The results from these studies demonstrated that for both inhalation and instillation, only the TiO(2) particle formulations with the largest components of both alumina and amorphous silica surface treatments produced mildly adverse pulmonary effects when compared to the base reference control particles. In summary, two major conclusions can be drawn from these studies: (1) surface treatments can influence the toxicity of TiO(2) particles in the lung; and (2) the intratracheal instillation-derived, pulmonary bioassay studies represent an effective preliminary screening tool for inhalation studies with the identical particle-types used in this study.


Assuntos
Administração por Inalação , Materiais Revestidos Biocompatíveis/toxicidade , Intubação Intratraqueal , Pulmão/efeitos dos fármacos , Titânio/administração & dosagem , Titânio/toxicidade , Aerossóis , Óxido de Alumínio/toxicidade , Animais , Biomarcadores/análise , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Relação Dose-Resposta a Droga , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/patologia , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Dióxido de Silício/toxicidade
9.
Clin Pharmacol Ther ; 36(3): 343-9, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6467794

RESUMO

Plasma levels of desipramine (DMI) and the unconjugated form of its principal metabolite 2-hydroxydesipramine (OH-D) were measured under steady-state conditions in nine depressed inpatients during treatment with 75 mg DMI every 12 hr and after at least 1 wk of an increased dose of DMI (after steady state). When DMI dosage was raised after an initial steady state had been reached, the rise in plasma DMI level was proportionately greater than the increase in dosage, suggesting saturation of DMI elimination pathways. Levels of OH-D rose in proportion to dose, suggesting saturation of DMI elimination by 2-hydroxylation could not explain DMI plasma level changes. In contrast, there were no dose-dependent effects on the disposition of amitriptyline or its metabolite nortriptyline in subjects receiving the same amitriptyline dose.


Assuntos
Transtorno Depressivo/metabolismo , Desipramina/análogos & derivados , Desipramina/metabolismo , Administração Oral , Adolescente , Adulto , Idoso , Amitriptilina/sangue , Cromatografia Líquida de Alta Pressão , Transtorno Depressivo/tratamento farmacológico , Desipramina/sangue , Desipramina/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Nortriptilina/sangue , Distribuição Aleatória
10.
Am J Psychiatry ; 143(12): 1597-600, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3789215

RESUMO

Desipramine and its metabolite 2-hydroxydesipramine were measured in the milk of a nursing mother and in the plasma of the mother and infant during administration of 300 mg/day of desipramine to the mother. Similar concentrations of both compounds were found in maternal plasma and milk. A pharmacokinetic plot of the milk over 24 hours showed the expected rise and fall of the substances following a single nighttime dose. Neither parent compound nor metabolite could be detected in the infant's serum even though the measurements were made shortly after peak ingestion by the infant. Furthermore, no clinical signs of toxicity were observed in the infant after 3 weeks of treating the mother with desipramine.


Assuntos
Aleitamento Materno , Desipramina/análogos & derivados , Desipramina/análise , Recém-Nascido/sangue , Leite Humano/análise , Adulto , Transtorno Depressivo/sangue , Transtorno Depressivo/tratamento farmacológico , Desipramina/metabolismo , Feminino , Humanos , Cinética
11.
Environ Health Perspect ; 108(11): 1085-90, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11102301

RESUMO

Declines in amphibian populations, and amphibians with gross malformations, have prompted concern regarding the biological status of many anuran species. A survey of bullfrogs, Rana catesbeiana, and green frogs, Rana clamitans, conducted in central and southern New Hampshire showed malformed frogs at 81% of the sites sampled (13 of 16 sites). Brain gonadotropin-releasing hormone (GnRH) and the synthesis of androgens and estradiol, hormones essential to reproductive processes, were measured from limb-malformed and normal (no limb malformation) frogs. Normal frogs had significantly higher concentrations (nearly 3-fold) of in vitro produced androgens and of brain GnRH than malformed frogs. Because most malformations are thought to occur during development, we propose that environmental factors or endocrine-disrupting chemicals that may cause developmental abnormalities also act during early development to ultimately cause abnormally reduced GnRH and androgen production in adult frogs. The consequences of reduced GnRH and androgens on anuran reproductive behavior and population dynamics are unknown but certainly may be profound and warrant further research.


Assuntos
Hormônios Esteroides Gonadais/metabolismo , Rana catesbeiana/anormalidades , Rana catesbeiana/metabolismo , Ranidae/anormalidades , Ranidae/metabolismo , Androgênios/metabolismo , Animais , Encéfalo/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/toxicidade , Estradiol/metabolismo , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Técnicas In Vitro , Deformidades Congênitas dos Membros/etiologia , Deformidades Congênitas dos Membros/metabolismo , Masculino , New Hampshire , Testículo/anormalidades
12.
Bone Marrow Transplant ; 23(12): 1317-20, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10414922

RESUMO

Varicella zoster virus (VZV) infection is a frequent complication following bone marrow transplantation (BMT). Involvement of the ophthalmic division of the trigeminal nerve, herpes zoster ophthalmicus (HZO), can result in significant and potentially vision-threatening ocular complications. We report the frequency and characteristics of HZO following BMT, including the timing of infection, treatment, ocular complications, and visual outcome. Between 1983 and 1997, 572 patients underwent BMT and seven children developed HZO at a median of 150 days following transplantation. All but one of the children had undergone allogeneic BMT. All of the children were treated with acyclovir after onset of the rash but none had received prophylactic therapy. All seven children developed ocular complications within the first 4 weeks following the onset of the dermatomal rash but none reported any symptoms during this period. Complications included keratitis in six, anterior uveitis in three and scleritis in one. Keratitis was an early complication developing within the first 4 weeks, while anterior uveitis and scleritis occurred later in the course of the disease. The high frequency of ocular complications and lack of symptoms in children with HZO following BMT suggests that early ophthalmologic evaluation is warranted in this group of patients. Prompt diagnosis and treatment of ocular complications is essential in the prevention of acute and long-term ocular sequelae in these children.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Herpes Zoster Oftálmico/etiologia , Adolescente , Criança , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/complicações , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia
13.
Obstet Gynecol ; 69(2): 175-8, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3808503

RESUMO

Two-dimensional and pulsed Doppler ultrasound techniques were used to examine 87 fetuses between 17 and 41 weeks' gestation in order to compare pulmonary artery and aortic outflow diameters, mean and maximal flow velocities, and transvalve flows. For purposes of analysis, fetuses were divided into two groups: those less than 31 weeks, and those of 31 weeks or more. Diameters of the pulmonary artery and aortic outflow region increased with advancing gestational age (P less than .001), while mean and maximal Doppler flow velocities did not change. Transvalve volume flow increased across both regions (pulmonary artery from 381 +/- 12 mL/minute to 530 +/- 13 mL/minute and aortic outflow from 286 +/- 10 mL/minute to 410 +/- 13 mL/minute, P less than .001) with advancing gestation. Pulmonary artery diameters were larger than aortic outflow diameters in both groups (P less than .01), while mean Doppler flow velocities were not significantly different. Maximal Doppler flow velocities were greater in the aorta than in the pulmonary artery (P less than .001), and transvalve flow was greater across the pulmonary artery than the aorta in both groups (P less than .05, ratio 1.3:1). This work demonstrates differences in fetal pulmonary artery and aortic outflow anatomy and physiology that must be considered in evaluating studies of fetal cardiac physiology.


Assuntos
Aorta/embriologia , Ecocardiografia , Feto/anatomia & histologia , Artéria Pulmonar/embriologia , Aorta/fisiologia , Velocidade do Fluxo Sanguíneo , Circulação Coronária , Idade Gestacional , Humanos , Artéria Pulmonar/fisiologia
14.
Obstet Gynecol ; 77(4): 551-7, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2002978

RESUMO

The fetal cardiac and placental circulations are interconnected through the umbilical venous and arterial vasculature. We hypothesized that alterations in umbilical venous blood flow velocities are present in fetuses with abnormal umbilical arterial circulation, and further, that changes in inferior vena cava blood flow velocities occur with, and might explain, these variations in umbilical venous blood flow velocities. Umbilical venous and inferior vena cava blood flow velocities were examined in 15 normal fetuses and in 59 fetuses with abnormalities that included absent end-diastolic umbilical artery blood flow velocities (N = 21) or abnormal heart rates (N = 27). Inferior vena cava velocities were also analyzed in 11 other fetuses with anomalies or known growth or placental abnormalities who had abnormal umbilical venous blood flow velocities. In normal fetuses, variations in umbilical venous velocities occurred during fetal activity or with fetal breathing; however, no variation in velocity corresponded with heart rate. Eleven of 21 fetuses with absent end-diastolic velocities in the umbilical artery demonstrated decreases in umbilical venous velocities ("venous pulsations") during arterial diastole. Blood flow velocities in the reverse direction, from the right atrium into the inferior vena cava with atrial contraction, were significantly greater in these fetuses than in those without umbilical venous pulsations (27.5 +/- 14.9% and 7.5 +/- 5.7% of total forward flow velocity, respectively; P less than .001). Venous pulsations were also seen in fetuses with abnormally fast or slow heart rates; reverse flow with atrial contraction in the inferior vena cava was likewise greater than normal in these fetuses.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arritmias Cardíacas/fisiopatologia , Doenças Fetais/fisiopatologia , Feto/fisiologia , Veias Umbilicais , Veia Cava Inferior , Velocidade do Fluxo Sanguíneo , Doenças Fetais/diagnóstico por imagem , Humanos , Ultrassonografia Pré-Natal
15.
Obstet Gynecol ; 84(6): 1033-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7970460

RESUMO

OBJECTIVE: To describe ethnic differences in tobacco use during pregnancy in a clinical population of Mexican-American and non-Hispanic white women. METHODS: Subjects were randomly selected from all patients attending a university-based obstetrics clinic in Tucson, Arizona. Of 555 subjects selected, 367 were interviewed and had their urinary cotinine levels measured. The 37 subjects who refused an interview and the 136 who were selected but not interviewed did not differ from other subjects regarding ethnicity, education, obstetric history, or smoking status. The interviewer gathered standard demographic and obstetric information as well as data on smoking behavior. Subjects were interviewed in Spanish or English by a bilingual interviewer using a standardized questionnaire. Statistical techniques included chi 2 test, t test, and logistic regression. RESULTS: The odds for Mexican-American women to have been smokers were 3.39 times lower than for non-Hispanic white women. The odds of quitting during pregnancy were 4.71 times higher for Mexican-Americans (95% confidence interval 1.66-13.38). Urinary cotinine values verified the latter rates. Mexican-American smokers reported smoking significantly fewer cigarettes than non-Hispanic white women (t = 2.34, P < .05). CONCLUSIONS: In comparing Mexican-American and non-Hispanic white women, we found marked differences in smoking behavior during pregnancy. Mexican-Americans were nearly three times more likely to quit than non-Hispanic whites, and those who continued to smoke showed greater reductions in cigarettes per day. These results show behavioral changes in Mexican-Americans during pregnancy that meaningfully alter the risk profile for the fetus. Understanding the basis for this behavioral change may facilitate the development of preventive measures for other ethnic groups.


Assuntos
Americanos Mexicanos/estatística & dados numéricos , Gravidez , Fumar/epidemiologia , População Branca/estatística & dados numéricos , Adulto , Arizona/epidemiologia , Cotinina/urina , Feminino , Humanos , Abandono do Hábito de Fumar , Fatores Socioeconômicos
16.
Obstet Gynecol ; 87(1): 83-8, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8532273

RESUMO

OBJECTIVE: To examine the incidence of very low birth weight (VLBW) neonates, defined as those weighing less than 1500 g, delivered by adolescents compared with the general obstetric population. METHODS: A retrospective observational study of 16,857 women delivering live-born infants from January 1, 1989, to June 30, 1993, was conducted at the University of Arizona Health Sciences Center. Adolescents were defined as those having a maternal age of 18 years or less at the time of delivery. The rate of VLBW infants delivered to adolescent mothers was compared with the general obstetric population (women at least 19 years old) using chi 2 analysis, multiple analysis of variance, and multiple linear regression. RESULTS: During the study period, 204 VLBW infants were delivered, yielding an overall VLBW delivery rate of 1.2%. Adolescents had a VLBW delivery rate that was considerably higher than the general obstetrical population: 35 of 1758 (2.0%) versus 169 of 15,099 (1.1%) (P = .002). Whereas adolescents accounted for 10.6% of the total deliveries during the study period, they delivered 17% of the VLBW neonates. The relative risk of an adolescent delivering a VLBW infant was 1.7 (95% confidence interval 1.2-2.2). CONCLUSION: Preterm birth is one of the major unresolved problems in modern obstetrics. Although the association between adolescence and preterm birth has been reported previously, specific attention has not been focused on the VLBW neonate. We conclude that adolescents deliver a disproportionate number of VLBW infants.


Assuntos
Recém-Nascido de muito Baixo Peso , Gravidez na Adolescência , Adolescente , Análise de Variância , Feminino , Humanos , Incidência , Recém-Nascido , Modelos Lineares , Gravidez , Estudos Retrospectivos
17.
Obstet Gynecol ; 87(4): 617-20, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8602319

RESUMO

OBJECTIVE: To examine effects of fluid administration on inferior vena cava pressure and umbilical venous Doppler velocities in the term fetal lamb. METHODS: With the ewe given inhalation anesthetics, eight chronically instrumented intrauterine fetal lambs at 125-135 days' gestation were given normal saline fluid boluses. Inferior vena cava peak pressures and umbilical venous Doppler velocities were measured before, during, and after administration of normal saline. Pressures were obtained with fluid-filled and solid state pressure transducers. RESULTS: Umbilical venous Doppler velocity pulsations developed in six fetuses after 120 mL and all eight fetuses after 240 mL of fluid were administered. Inferior vena cava peak pressure increased from 5.15 +/- 2.7 to 10.9 +/- 3.9 mmHg (P < .001). Heart rate did not change significantly, and umbilical arterial systolic-to-diastolic velocity ratios decreased (P < .03). CONCLUSION: Umbilical venous Doppler velocity pulsations developed after fluid administration and were associated with increases in inferior vena cava peak pressure. These findings suggest that umbilical venous pulsations develop when fetal venous pressures are elevated.


Assuntos
Feto/fisiologia , Veias Umbilicais/fisiologia , Veia Cava Inferior/fisiologia , Animais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Pulso Arterial/fisiologia , Ovinos , Ultrassonografia Doppler
18.
Obstet Gynecol ; 81(6): 983-8, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8497367

RESUMO

OBJECTIVE: To assess the validity of Doppler flow sonography for the prediction of malignancy in adnexal masses and to compare the results with two-dimensional ultrasonographic examination and CA 125 levels. METHODS: In a cross-sectional study, 55 patients with adnexal masses were examined using Doppler sonography to measure the resistance index of tumor-associated blood flow profiles. In addition, abdominal and transvaginal ultrasound examinations were performed and preoperative CA 125 serum levels were assessed. RESULTS: Sixteen patients had malignant tumors and 39 had benign tumors. A resistance index cutoff of less than or equal to 0.8 showed the highest sensitivity (93.8%), with a specificity of 56.4%, a positive predictive value of 46.8%, and a negative predictive value of 95.7%. Compared with two-dimensional sonographic evaluation using either a scoring system or subjective assessment, and with CA 125 levels, the resistance index showed higher sensitivity and negative predictive value but lower specificity and positive predictive value. False-positive resistance index values were prevalent with endometriosis, leiomyomata, and mucinous cystadenoma. The combination of the resistance index with either the sonographic features or CA 125 increased the sensitivity and negative predictive value to 100%, with only a slight decrease in specificity and positive predictive value, but was not superior to the combination of two-dimensional sonography and CA 125. CONCLUSION: Doppler sonographic evaluation of resistance indexes in the vessels of adnexal masses increased the sensitivity of two-dimensional sonography and CA 125. However, 46% of positive Doppler results were false and 37.5% of the benign tumors had low resistance indexes, thus limiting the validity of this technique for screening programs.


Assuntos
Doenças dos Anexos/diagnóstico por imagem , Antígenos Glicosídicos Associados a Tumores/sangue , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Doenças dos Anexos/diagnóstico , Doenças dos Anexos/epidemiologia , Estudos Transversais , Feminino , Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias dos Genitais Femininos/epidemiologia , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassom , Ultrassonografia/métodos
19.
Obstet Gynecol ; 71(6 Pt 2): 978-81, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3287252

RESUMO

Two-dimensional Doppler echocardiography was used to diagnose congestive heart failure in a fetus with a large sacrococcygeal teratoma. Ultrasound performed for size-date inconsistency revealed a 27.5-week fetus with hydrops and a large solid and cystic mass in the sacral region. Fetal echocardiography showed dilated ventricles and a pericardial effusion; Doppler ultrasound demonstrated increased velocities and volume flows, along with tricuspid and mitral regurgitation. At delivery, the mass was bleeding actively, the amniotic fluid was markedly bloody, and the neonatal hematocrit was 10%. We postulate that intrauterine hemorrhage from the teratoma led to anemia and high-output cardiac failure confirmed by Doppler echocardiography, and suggest that all fetuses with sacrococcygeal teratomas be evaluated by two-dimensional Doppler echocardiography to detect the presence of congestive heart failure, in order to allow well-timed therapeutic interventions.


Assuntos
Ecocardiografia , Doenças Fetais/diagnóstico , Insuficiência Cardíaca/etiologia , Diagnóstico Pré-Natal , Teratoma/complicações , Adulto , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Gravidez , Região Sacrococcígea , Teratoma/diagnóstico , Ultrassonografia
20.
Obstet Gynecol ; 89(6): 953-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9170473

RESUMO

OBJECTIVE: To identify the source of umbilical venous velocity pulsations, times of transmission from the atrial contraction pressure waveform to velocity waves in the inferior vena cava, ductus venosus, intra-abdominal umbilical vein, and intra-amniotic umbilical vein were examined. METHODS: Five lamb fetuses at 125-135 days' gestation were instrumented with solid state pressure transducers in the inferior vena cava, fluid-filled catheters in the inferior vena cava and descending aorta, and epicardial pacemakers. Three to 5 days postoperatively, inferior vena cava, ductus venosus, and umbilical vein velocities were examined with Doppler ultrasound. Normal saline was administered and umbilical vein velocity pulsations developed (180 +/- 60 mL). In three fetuses, premature atrial contractions were induced under baseline conditions and after umbilical vein velocity pulsations developed. RESULTS: Times of transmission from the atrial contraction pressure waveform until velocity decreases in the fetal venous system were significantly different in the inferior vena cava, ductus venosus, intra-abdominal umbilical vein, and intra-amniotic umbilical vein (P < .001). Times increased with the distance from the atrium. Inferior vena cava pressure increased with fluid administration from 3.7 +/- 4.7 mmHg to 9.3 +/- 2.3 mmHg (P < .01). Time from increased pressure waveforms with induced premature atrial contractions to the nadir of subsequent umbilical vein velocity waves decreased from 0.123 +/- 0.047 seconds before saline administration to 0.072 +/- 0.039 seconds after saline administration (P < .001). CONCLUSION: Transmission time of atrial pressure into the venous circulation increases with distance from the atrium and decreases with volume loading. Umbilical venous velocity pulsations derive from atrial pressure changes transmitted in a retrograde fashion.


Assuntos
Coração Fetal/fisiologia , Contração Miocárdica/fisiologia , Pulso Arterial/fisiologia , Veias Umbilicais/fisiologia , Animais , Velocidade do Fluxo Sanguíneo , Pressão , Ovinos
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