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1.
Surg Neurol Int ; 8: 15, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28217394

RESUMEN

BACKGROUND: Basilar tip aneurysms are one of the most complex vascular lesions to treat surgically because of their location, depth of the approach, and close proximity of vital neurovascular structures such as the mesencephalon, cranial nerves, perforating arteries to the thalamus. There are different surgical approaches utilized to reach basilar tip aneurysms, namely, pterional, pretemporal, orbitozygomatic, subtemporal, and anterior petrosectomy. Each of them has its advantages and limitations. METHODS: In this paper, we present our personal experience with the use of subtemporal approach. The technique is described in detail including its nuances and potential pitfalls. RESULTS: The subtemporal approach is indicated for basilar tip aneurysms located at the level of the floor of the sella turcica to 1 cm above the dorsum sellae. CONCLUSION: Subtemporal approach offers good surgical corridor for the management of these complex vascular lesions.

3.
Bioorg Med Chem Lett ; 11(9): 1161-4, 2001 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-11354367

RESUMEN

Small and simple molecules mimicking a Lys-Tyr-Lys triad and some 'mutant' derivatives were designed and synthesized. These-compounds react with benzylpenicillin in water (75mM phosphate buffer, pH 7), apparently through general base assistance by the phenolic moiety. Class C beta-lactamase has a Lys-Tyr-Lys triad in its active site, and our finding gives some insight into the role of this triad in the enzymatic beta-lactam hydrolysis mechanism.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Oligopéptidos/química , Penicilina G/farmacología , Tirosina/química , Inhibidores de beta-Lactamasas , Inhibidores Enzimáticos/química , Cinética , Imitación Molecular , Penicilina G/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
4.
Steroids ; 66(2): 87-91, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11146087

RESUMEN

Localization of steroid sulfatase, a membrane-bound microsomal enzyme, in human fallopian tubes was immunohistochemically investigated, and expression of RNA was confirmed by competitive RT-PCR. Human fallopian tubes were obtained from 10 patients in follicular and early luteal phases during gynecological laparotomy. An anti-human rabbit polyclonal antibody was prepared against sulfatase protein purified from human placenta. Total RNA was isolated from epithelium of fallopian tubes. A heterologous RNA competitor was designed, and competitive RT-PCR was carried out. Steroid sulfatase was localized to the cytoplasm of epithelial cells. With respect to the positive staining of cells, the number of positive secretory cells was higher than that of ciliated cells. A significantly higher number of positive cells was found in tissue obtained from the early luteal phase than that found in tissue from the follicular phase. An abundant expression of sulfatase mRNA in early luteal phase was also observed. This study demonstrates, for the first time, that steroid sulfatase is localized to human epithelial cells and that steroid sulfatase staining and mRNA expression changes with the menstrual cycle. These results suggest that sulfatase in the fallopian tube may be involved in controlling the local steroid environment, which appears to regulate aspects of the physiological reproductive function of the fallopian tube.


Asunto(s)
Arilsulfatasas/metabolismo , Trompas Uterinas/enzimología , Adulto , Secuencia de Bases , Cartilla de ADN , Femenino , Humanos , Inmunohistoquímica , Ciclo Menstrual , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esteril-Sulfatasa
5.
Mol Hum Reprod ; 6(5): 469-73, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10775652

RESUMEN

The aim of this study was to evaluate the effect of lactoferrin (LF) on the proliferation of human endometrial stroma cells. In addition, we compared the effect of LF, oestradiol and epidermal growth factor (EGF) on the proliferation of human endometrial stroma cells. Human endometrial tissue was obtained from patients with a normal menstrual cycle in the proliferative phase and the stroma cells were isolated and cultured in vitro. When LF was added to the culture medium, the rate of cell proliferation increased significantly in comparison to controls (P < 0.01). The enhanced rate of proliferation induced by LF was neutralized by the addition of anti-LF monoclonal antibody. The effect of LF on cell proliferation at a concentration of 100 ng/ml was similar to that of 10 nmol/l oestradiol, but less than that of 10 mg/ml EGF. When LF was added in combination with either oestradiol or EGF, no additive effects on cell proliferation were observed. Based on the present results, it is suggested that LF has a potential biological effect in the proliferation of human endometrium.


Asunto(s)
Endometrio/citología , Endometrio/efectos de los fármacos , Lactoferrina/farmacología , Lactoferrina/fisiología , División Celular , Células Cultivadas , Factor de Crecimiento Epidérmico/farmacología , Estradiol/farmacología , Femenino , Humanos , Células del Estroma/efectos de los fármacos
6.
Placenta ; 20(2-3): 175-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10195738

RESUMEN

Lactoferrin (LF) has been found in most biological fluids including amniotic fluid and cervical mucus in pregnant women and is released from neutrophils in response to inflammation. It is an important component of the host defence against microbial infections due to its antimicrobial properties. Premature labour is caused by amniotic infection and high concentrations of inflammatory cytokines in amniotic fluid with infection are well established. In the present study, LF levels of intrauterine infection in amniotic fluid were measured and the biological significance of LF was investigated. The effects of LF on IL-6 production in cultured amnion cells were also investigated. The concentrations of LF and IL-6 in amniotic fluid with chorioamnionitis (CAM) were 8.76+/-0.65 microg/ml and 6.92+/-4.88 ng/ml (n = 28), respectively, and both were significantly higher (P<0.01) than those without CAM (0.86+/-0.81 microg/ml and 0.34+/-0.25 ng/ml; n = 31). LF and IL-6 levels were significantly higher (P<0.01) with CAM. A significant positive correlation between LF and IL-6 levels in amniotic fluid was found (r = 0.91, P<0.01). To our knowledge, this was the first study of its kind, which shows that IL-6 production induced by lipopolysaccharide in cultured cells was significantly inhibited below physiological concentration of LF in the amnion. In addition, the immunohistochemical localization of LF in fetal membranes was investigated. In the fetal membranes with CAM, strong positive staining was observed in amniotic and chorionic membranes, with leucocyte migration, while weak staining was observed in membranes without CAM. These results show conclusively that LF suppresses amniotic IL-6 production under the conditions of intrauterine infection.


Asunto(s)
Líquido Amniótico/química , Corioamnionitis/metabolismo , Lactoferrina/análisis , Amnios/química , Corion/química , Femenino , Humanos , Inmunohistoquímica , Interleucina-6/análisis , Lipopolisacáridos/farmacología , Embarazo , Valores de Referencia
7.
Nihon Rinsho ; 57 Suppl: 274-8, 1999 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-10778116
8.
J Obstet Gynaecol Res ; 24(4): 291-7, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9798360

RESUMEN

OBJECTIVE: Aromatization in the the fetal brain is thought to be involved both in sex differentiation during early development and in adult sexual behavior. Although recently the relationship between aromatase and catecholamine has been discussed, the effect of stress on aromatase in the fetal brain has not been clarified. Therefore, in the present study, localization of aromatase and the inhibitory effects of catecholamines and maternal stress on aromatase activity in the fetal rat brain were examined. METHODS: Localization of aromatase cytochrome P-450 using a specific polyclonal antiserum against human placenta aromatase was examined, and the inhibitory effects of dopamine and norepinephrine on aromatase activity in vitro were studied. Further, the influences of intrauterine stress on aromatase activity in the prenatal rat brain were evaluated in vivo. RESULTS: Aromatase-immunoreactive neurons are located principally in the medial amygdaloid nucleus. Aromatase activity in the fetal rat brain was competitively inhibited by dopamine and norepinephrine, with Ki values of 120 microM and 100 microM, respectively. Aromatase activity in the fetal brain was significantly lower in stressed rats given 1.5% salt water (89.2 +/- 17.5 fmol/mg/hr; n = 4) (p < 0.05) than in the control group (123.1 +/- 10.0 fmol/mg/hr; n = 4). CONCLUSION: Aromatase activity in the prenatal rat brain is influenced by catecholamine metabolism during intrauterine stress.


Asunto(s)
Amígdala del Cerebelo/enzimología , Aromatasa/metabolismo , Catecolaminas/farmacología , Desarrollo Embrionario y Fetal/fisiología , Estrés Fisiológico/enzimología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/embriología , Animales , Aromatasa/inmunología , Aromatasa/fisiología , Encéfalo/embriología , Encéfalo/enzimología , Encéfalo/ultraestructura , Catecolaminas/fisiología , Modelos Animales de Enfermedad , Dopamina/farmacología , Dopamina/fisiología , Femenino , Cabras , Humanos , Inmunohistoquímica , Técnicas In Vitro , Cinética , Microsomas/metabolismo , Microsomas/fisiología , Norepinefrina/farmacología , Norepinefrina/fisiología , Embarazo , Ratas , Cloruro de Sodio/farmacología , Estrés Fisiológico/fisiopatología
9.
Adv Exp Med Biol ; 443: 267-71, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9781369

RESUMEN

Lactoferrin (Lf) has been found in most biological fluids including amniotic fluid and cervical mucoids in pregnant women, and released from neutrophils in response to the inflammation. As Lf possesses antimicrobial properties, it is widely considered to be an important component of the host defence against microbial infections. It is known that premature labor is caused by amniotic infection with the increase of prostaglandin production. High concentration of the inflammatory cytokines: interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) in the amniotic fluid has been known. However, changes of Lf in amniotic fluid with infection has not been reported. In the present study, Lf concentrations in amniotic fluid were measured under the intra-uterine infections state and the biological significance of Lf was investigated. The effects of Lf on the IL-6 and IL-6mRNA production in cultured amnion cells were also investigated. The concentrations of Lf and IL-6 in amniotic fluid with CAM were 8.76 +/- 0.65 micrograms/ml and 6.92 +/- 4.88 ng/ml (n = 28) respectively and both were significantly higher (p < 0.01) than those without CAM [0.86 +/- 0.81 microgram/ml and 0.34 +/- 0.25 ng/ml (n = 31)]. Significant positive correlation (r = 0.91, p < 0.01) between Lf and IL-6 levels in amniotic fluid was found. IL-6 production induced by lipopolysaccharide (LPS) (100 ng/ml) in cultured amnion cells was significantly inhibited (p < 0.05) under the physiological concentration of Lf in amnion. Total RNA was extracted from the amniotic cells by guianizine solution. RT-PCR procedure and product analysis were performed from one microgram aliquote of total RNA. beta-actin was used as an international standard and c-DNA samples were followed by 30 cycles of PCR. RT-PCR product of IL-6 mRNA was detected by Southern hybridization. Expression of IL-6 mRNA was inhibited by the addition of Lf. From the results, the possibility that Lf might suppress amniotic IL-6 production under the condition of amniotic infection is suggested. It is also suggested that Lf might act as self defence mechanism from intra-uterine infection.


Asunto(s)
Amnios/microbiología , Líquido Amniótico/metabolismo , Infecciones Bacterianas/diagnóstico , Interleucina-6/biosíntesis , Lactoferrina/metabolismo , Amnios/efectos de los fármacos , Amnios/metabolismo , Líquido Amniótico/microbiología , Células Cultivadas , Femenino , Humanos , Lactoferrina/farmacología , Embarazo , ARN Mensajero/análisis , ARN Mensajero/efectos de los fármacos
10.
Nihon Rinsho ; 55(11): 2902-7, 1997 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-9396285

RESUMEN

Function of hypothalamic-pituitary-ovarian axis is an essential factor for the maintenance of regular cycles in mature women. The disturbance of function of those organs causes gonadal dysfunction such as anovulation, amenorrhea and menstrual disorders. Therefore, the correct diagnosis for the assessment of CNS and ovarian function is clinically important to treat the patients those who have an menstrual disorders. In this review, the mechanism of normal gonadal cycles and the diagnostic method and the treatment of gonadal dysfunction are described.


Asunto(s)
Trastornos Gonadales/diagnóstico , Amenorrea/diagnóstico , Amenorrea/tratamiento farmacológico , Anovulación/diagnóstico , Anovulación/tratamiento farmacológico , Femenino , Trastornos Gonadales/etiología , Humanos
11.
J Steroid Biochem Mol Biol ; 61(3-6): 117-26, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9365180

RESUMEN

The diverse function of human placental aromatase including estradiol 6alpha-hydroxylase and cocaine N-demethylase activity are described, and the mechanism for the simultaneous metabolism of estradiol to 2-hydroxy- and 6alpha-hydroxyestradiol at the same active site of aromatase is postulated. Comparison of aromatase activity is also made among the wild type and N-terminal sequence deleted forms of human aromatase which are recombinantly expressed in Escherichia coli. Aromatase cytochrome P450 was reconstituted and incubated with [6alpha,7alpha-(3)H2,4-(14)C]estradiol, 7-ethoxycoumarin, and [N-methyl-(3)H3]cocaine. 6Alpha-hydroxy[7alpha-(3)H,4-(14)C]estradiol was isolated as the metabolite of estradiol and the 3H-water release method based on the 6alpha-3H label was established. The initial rate kinetics of the 6alpha-hydroxylation gave Km of 4.3 microM, Vmax of 4.02 nmol min(-1) mg(-1), and turnover rate of 0.27 min(-1). Testosterone competed dose-dependently with the 6alpha-hydroxylation and showed the Ki of 0.15 microM, suggesting that they occupy the same binding site of aromatase. The deethylation of 7-ethoxycoumarin showed Km of 200 microM, Vmax of 12.5 nmol min(-1) mg(-1) and turnover rate of 1.06 min(-1). The N-demethylation of cocaine was analysed by the 3H-release method, giving Km of 670 microM, Vmax of 4.76 nmol min(-1) mg(-1), and turnover rate of 0.49 min(-1). All activity was dose-responsively suppressed by anti-aromatase P450 monoclonal antibody MAb3-2C2. The N-terminal 38 amino acid residue deleted form of aromatase P450 was expressed in particularly high yield giving a specific activity of 397 +/- 83 pmol min(-1) mg(-1) (n = 12) of crude membrane-bound particulates with a turnover rate of 2.6 min(-1).


Asunto(s)
Aromatasa/química , Aromatasa/genética , Aromatasa/metabolismo , Sitios de Unión/genética , Femenino , Humanos , Cinética , Placenta/enzimología , Embarazo , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia , Relación Estructura-Actividad
12.
Endocrinology ; 137(9): 3791-6, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8756548

RESUMEN

In studying the diverse functions of aromatase we found that purified and reconstituted aromatase also catalyzes O-deethylation of 7-ethoxycoumarin. Aromatase cytochrome P450 was purified from human term placentas by monoclonal antiaromatase P450 antibody-Sepharose 4B column chromatography. Kinetic analysis of the O-deethylation of 7-ethoxycoumarin by reconstituted aromatase showed Km of 200 microM, Vmax of 12.5 nmol.min-1.mg-1, and turnover rate of 1.06 min-1. 7-Ethoxycoumarin competitively inhibited androstenedione aromatization, the Ki was 180 microM. Fadrozole (CGS16949A), a specific competitive aromatase inhibitor, and MAb3-2C2, an antiaromatase P450 monoclonal antibody, inhibited both aromatase and 7-ethoxycoumarin O-deethylase activities dose responsively. The IC50 of Fadrozole was 33 nM for aromatase and 67 nM for 7-ethoxycoumarin O-deethylase. The IC50 of MAb3-2C2 was 1.1 micrograms IgG for aromatase and 4.0 micrograms IgG for 7-ethoxycoumarin O-deethylase. These results indicate that the two enzyme activities are catalyzed by the same active site of the cytochrome P450. Contrary to the previous postulate on the mechanism-based inactivation of microsomal aromatase by 4-androstene-3,6,17-trione, we found that with purified aromatase, both the initial 19-hydroxylase and the after lyase reactions are simultaneously inactivated by the steroid suicide inhibitor.


Asunto(s)
Aromatasa/metabolismo , Cumarinas/metabolismo , Androstenos/farmacología , Anticuerpos Monoclonales/inmunología , Aromatasa/inmunología , Inhibidores de la Aromatasa , Activación Enzimática/efectos de los fármacos , Fadrozol/farmacología , Humanos
13.
Jpn Circ J ; 60(9): 691-8, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8902587

RESUMEN

To assess the early stage of atherosclerosis of the thoracic descending aorta, we evaluated morphological atheromatous lesions (atherosis) and the stiffness parameter of the artery (beta; sclerosis) in 24 male rabbits using echography. Male Japanese white rabbits weighing 2.5-3.0 kg were fed a diet containing 1% cholesterol for 7 (n = 8) or 14 weeks (n = 8). Rabbits fed a normal diet were used as controls (n = 8). Atheromatous lesions were evaluated with intravascular ultrasound (IVUS: Aloka, 20 MHz, 6F). We also calculated beta using M-mode echography (7.5 or 10 MHz) and direct aortic pressure measurement. Thickening of the intima-media complex was clearly observed with IVUS in the 14-week group but was not detected in the others. Histologically, only a thin layer of foamy cells on the intima (thickness < 20 microns) was observed in the 7-week group. The value of beta was significantly increased in both the 7-week (4.7 +/- 2.2) and 14-week groups (4.5 +/- 0.8) compared with controls (1.7 +/- 0.9, both p < 0.01). These results suggest that the development of atherosis might be preceded by vascular sclerosis during the early stage of atherosclerosis when the serum cholesterol level is high: at a time when the thin layer of foamy cells could not be detected by conventional IVUS.


Asunto(s)
Arteriosclerosis/diagnóstico por imagen , Túnica Íntima/patología , Túnica Media/patología , Animales , Arteriosclerosis/inducido químicamente , Arteriosclerosis/patología , Dieta Aterogénica , Masculino , Conejos , Túnica Íntima/diagnóstico por imagen , Túnica Media/diagnóstico por imagen , Ultrasonografía
14.
Endocr J ; 43(4): 363-8, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8930523

RESUMEN

2-Hydroxylation is one of the major metabolic pathways of estrogens and is believed to be catalyzed by a form of cytochrome P450. Recently it has been reported that estrogen 2-hydroxylase activity in human placenta is catalyzed by aromatase. Some investigators suggested the effect of catechol estrogen on human placental steroidogenesis which may be related to pregnancy-induced hypertension (PIH) through the inhibition of catechol-O-methyltransferase (COMT) activity. In order to better understand the interrelationship between placental aromatase and estrogen 2-hydroxylase activities in PIH patients, both activities were evaluated in the PIH placentas. Human placental microsomes obtained from PIH patients were incubated with [1 beta-3H]androstenedione or [2-3H]estradiol in the presence of NADPH. Aromatase and estrogen 2-hydroxylase activities were assessed by the tritium water method. The immunosuppression patterns of both activities due to monoclonal antiaromatase cytochrome P450 antibody (MAb3-2C2) were studied. Estrogen 2-hydroxylase activity was significantly higher in PIH placentas (4.7 +/- 0.9 pmol/min/mg protein, n = 7) than in normal placentas (3.0 +/- 0.7 pmol/min/mg protein, n = 7). When the PIH placental microsomes were subjected to immunosuppression by 1 to 100 micrograms IgG of MAb3-2C2, estrogen 2-hydroxylase activity was suppressed by 94 to 65% whereas aromatase activity was strongly suppressed by 72 to 17%, respectively. From our results of high estrogen 2-hydroxylase activity in PIH placentas, it is assumed that there is a different estrogen catalyzing mechanism in PIH placentas.


Asunto(s)
Aromatasa/metabolismo , Citocromo P-450 CYP1A1 , Sistema Enzimático del Citocromo P-450/metabolismo , Hipertensión/enzimología , Microsomas/enzimología , Placenta/enzimología , Complicaciones Cardiovasculares del Embarazo/enzimología , Esteroide Hidroxilasas/metabolismo , Anticuerpos Monoclonales/farmacología , Inhibidores de la Aromatasa , Inhibidores Enzimáticos/farmacología , Estradiol/metabolismo , Femenino , Retardo del Crecimiento Fetal/enzimología , Humanos , Cinética , Placenta/ultraestructura , Embarazo
15.
Gene ; 165(2): 321-2, 1995 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-8522198

RESUMEN

The flounder (Paralichthys olivaceus) growth hormone (GH)-encoding gene (fGH) and its promoter region were cloned and sequenced following amplification of genomic DNA by the polymerase chain reaction. The fGH gene is 2.1-kb long and consists of six exons and five introns. In the 5'-flanking region of the determined transcription start point, a potential TATA box is located at -24, and Pit-1/GHF-1-binding site candidates are located in the -70 to -53 and -133 to -141 regions.


Asunto(s)
Lenguado/genética , Genes/genética , Hormona del Crecimiento/genética , Regiones Promotoras Genéticas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Proteínas de Unión al ADN/genética , Exones/genética , Intrones/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , TATA Box , Factor de Transcripción Pit-1 , Factores de Transcripción/genética , Transcripción Genética/genética
16.
Nihon Rinsho ; 51(5): 1233-40, 1993 May.
Artículo en Japonés | MEDLINE | ID: mdl-8331791

RESUMEN

In the last two decades M-mode and two-dimensional echocardiography yielded outstanding improvements in diagnostic cardiology by providing readily available morphological and functional information of the heart as well as the great vessels. Recent advance of Doppler echocardiography makes it possible not only to examine the blood flow velocity but also to estimate the pressure gradient in the cardiovascular system. Moreover, advent of transesophageal echocardiography permits the routine visualization of certain cardiac regions that often cannot be visualized from the transthoracic views, such as the left atrial appendage and pulmonary vein. By using these echocardiographic techniques, the presence, severity, and hemodynamic consequences of heart failure due to various cardiovascular diseases can be determined noninvasively and repeatedly.


Asunto(s)
Ecocardiografía , Insuficiencia Cardíaca/diagnóstico por imagen , Adulto , Volumen Cardíaco , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Válvula Mitral/patología , Miocardio/patología , Sístole , Función Ventricular Izquierda
17.
Arch Orthop Trauma Surg ; 112(6): 299-301, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8123385

RESUMEN

Traumatic anterior dislocation of the hip is a relatively uncommon injury, and when it does occur it is frequently combined with osteochondral fracture of the femoral head or the acetabulum. Anterior dislocation of the hip with an associated fracture of the ipsilateral greater trochanter is extremely rare. This paper presents a case of this rare type of injury and clarifies the mechanism of the injury using a cadaver specimen.


Asunto(s)
Luxación de la Cadera/patología , Fracturas de Cadera/patología , Sínfisis Pubiana/lesiones , Adulto , Moldes Quirúrgicos , Estudios de Seguimiento , Curación de Fractura/fisiología , Luxación de la Cadera/terapia , Fracturas de Cadera/terapia , Humanos , Masculino , Traumatismo Múltiple/patología , Traumatismo Múltiple/terapia , Sínfisis Pubiana/patología , Tomografía Computarizada por Rayos X
18.
Am J Physiol ; 263(1 Pt 2): H109-16, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1636750

RESUMEN

Effect of changing afterload and inotropic states on inner and outer ventricular wall thickening. Am. J. Physiol. 263 (Heart Circ. Physiol. 32): H109-H116, 1992.--To study the differing behaviors of the inner (IH) and outer halves (OH) of the left ventricular (LV) free wall during an increasing afterload and changing inotropic states, we determined the LV pressure (LVP) and transmural (TM) and OH wall thickness (WTTM and WTOH) by sonomicrometry in 11 anesthetized dogs. The percent systolic wall thickening (% delta WT) and the fractional contribution (FC) were calculated. At rest, % delta WT of TM, IH, and OH were 22 +/- 1 (mean +/- SE), 33 +/- 3, and 13 +/- 2 (P less than 0.01 vs. IH), respectively. The FC of IH and OH were 74 +/- 5 and 29 +/- 4% (P less than 0.01 vs. IH), respectively. During increasing afterload by aortic constriction (AC) without drugs, % delta WT in IH was reduced to 22 +/- 2%, associated with unchanged % delta WT in OH (12 +/- 3%), whereas the FC of IH and OH were not altered from resting values. During AC with dobutamine infusion (3 micrograms.kg-1.min-1), the % delta WT and FC in each layer were not reduced from resting values. On the other hand, during AC with propranolol (2 mg bolus iv), the reduction of % delta WT in IH was greater (from 29 +/- 4 to 15 +/- 6%, P less than 0.01) than that in OH (from 11 +/- 2 to 10 +/- 3%; P less than 0.01 vs. IH). The FC in the IH was decreased (56 +/- 16%) by AC with propranolol, so that the difference in FC between IH and OH became insignificant (FCOH 40 +/- 13%, P greater than 0.1 vs. FCIH).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Corazón/fisiología , Contracción Miocárdica/fisiología , Animales , Aorta/fisiología , Simulación por Computador , Constricción , Dobutamina/farmacología , Perros , Ecocardiografía , Corazón/anatomía & histología , Corazón/efectos de los fármacos , Ventrículos Cardíacos , Hemodinámica , Isoproterenol/farmacología , Propranolol/farmacología , Descanso
19.
Jpn Circ J ; 55(6): 535-42, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1875520

RESUMEN

To evaluate the differences in shape and phase lag of the flow velocity curves in the superior (SVC) and inferior (IVC) venae cavae and the hepatic vein (HV), Doppler echocardiographic examination was performed in 40 healthy adults (aged 20 to 67 years, mean +/- SD: 39 +/- 12 years). Flow velocity patterns in each vein were characterized by 4 major deflections: S wave, a systolic forward flow; D wave, a diastolic forward flow; A wave, a small backward flow or reduction of diastolic forward flow due to atrial contraction; and O wave, a small backward flow or reduction of forward flow after the second heart sound. Except for a reduced phasic flow in a collapsed IVC, the venous flow velocity recordings in each vein demonstrated very similar pulsatile patterns and small differences in mean time lags of less than 50 msec. In general, the lowest values of peak A/peak S, peak O/peak S and peak D/peak S were observed in HV flow and the highest in IVC flow. Backflows of A and O waves were prominent in HV flow, but small and least frequent in IVC flow. These data suggest that the baseline of the central venous flow recordings might shift downward in HV flow and upward in IVC flow. However, even if both the baseline shift and amplitude of the flow curve were normalized in each venous flow velocity curve, apparent differences in shape of the flow velocity curves would remain. We concluded that the characteristics and differences of each central venous flow velocity pattern should be noted in studies of these areas.


Asunto(s)
Venas Hepáticas/fisiología , Venas Cavas/fisiología , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Ecocardiografía Doppler , Femenino , Venas Hepáticas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Flujo Pulsátil , Valores de Referencia , Vena Cava Inferior/fisiología , Vena Cava Superior/fisiología , Venas Cavas/diagnóstico por imagen
20.
Am J Cardiol ; 67(13): 1121-6, 1991 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-2024603

RESUMEN

To analyze left atrial (LA) pump function in normal subjects, in patients with essential hypertension and in patients with a healed myocardial infarction, LA dimension (aortic-root echogram) and pressure (catheter-tip manometer) were simultaneously recorded in 25 patients (8 normal subjects, 7 with hypertension and 10 with myocardial infarction). The pressure-dimension relation of the left atrium was composed of 2 loops: the A loop (expressing the pump function of the left atrium) and the V loop. LA dimension at the beginning of active LA shortening was significantly greater in hypertensive subjects (33 +/- 3 mm) and in those with myocardial infarction (32 +/- 4 mm) than in normal subjects (28 +/- 3 mm) (p less than 0.01, p less than 0.05, respectively). The area of the A loop significantly increased in subjects with hypertension (48 +/- 3 mm Hg.mm, p less than 0.01) and in subjects with myocardial infarction (29 +/- 10 mm Hg.mm, p less than 0.05), compared with normal subjects (20 +/- 8 mm Hg.mm). The mean fractional shortening velocity of the left atrium significantly increased in subjects with hypertension, compared with normal subjects and those with myocardial infarction (p less than 0.05 for both). LA peak wall tension during the LA active contraction period significantly increased with hypertension and with myocardial infarction, compared with normal subjects (p less than 0.01, p less than 0.05, respectively). The area of the A loop was directly proportional to the LA dimension at the beginning of active LA shortening (r = 0.53), p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Función del Atrio Izquierdo , Hipertensión/fisiopatología , Infarto del Miocardio/fisiopatología , Adulto , Anciano , Función del Atrio Izquierdo/fisiología , Presión Sanguínea , Cateterismo Cardíaco , Volumen Cardíaco/fisiología , Ecocardiografía , Femenino , Hemodinámica , Humanos , Hipertensión/diagnóstico por imagen , Hipertensión/patología , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/patología
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