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Biomedical subjects

C Ruiz

Publications and source records attributed to C Ruiz.

At least 91 records · Page 5Linked to original sources
PubMed1996

Lymphocyte subpopulations and catecholamines; daytime variations and relationships.

The diurnal variations and their possible relations with endogenous catecholamines have been studied in 16 apparently healthy subjects (8 women and 8 men, between 22-35 years of age). A butterfly cannula was inserted into the flexure vein of the elbow at 8 h and at 20 h, a blood sample being taken after three 15-minute intervals. Leukocytes, lymphocytes, monocytes, and granulocytes were quantified in a cell counter while lymphocyte subpopulations were determined with flow cytometry in cells labelled with specific monoclonal antibodies. Plasma catecholamine concentrations were measured by high-pressure liquid chromatography. Significant differences for leukocyte circulating levels were found, as well as for all subpopulations measured at different times of day, save NK cells and monocytes. A statistically significant correlation was also found both between leukocytes, all subpopulations and epinephrine save B lymphocytes and NK cells, and between total lymphocytes, T lymphocytes, CD4, CD4/45RA+ subtypes and norepinephrine. In conclusion, diurnal rhythms were proved to exist in leukocyte and lymphocyte subpopulations; the significant correlation between these cells and catecholamine plasma levels suggests the presence of a possible mechanism that connects the cellular immunity with determined hormones.

Adult↗
PubMed1996

[Drainage of loculated and/or multiloculated pleural effusions using a small caliber catheter and urokinase (pleuro-fibrinolysis)].

The main causes of pleural fluid drainage failure are known to be the formation of fibrin septa, increased viscosity in pleural fluid and inappropriate placement of chest tubes. Reports also tell us that such problems can be solved by using ultrasound as a guide for tube placement and by infusing intrapleural fibrinolytic agents to prevent the formation of septa and reduce the viscosity of pleural fluid. To assess our experience, the role and efficacy of administering intercavitary urokinase (UK) through a small caliber catheter (SCC) implanted with ultrasound guidance as part of the treatment for pleural effusions (PE) that are multiloculated and/or loculated. Fifty multiloculated and/or loculated PE were drained through a pig-tail type SCC between 8.2 and 10 F caliber inserted with ultrasound guidance. The criteria for prescribing the procedure were as follows: PE of any etiology with ultrasound confirmation of fibrin septa and/or multiloculation and absence of contraindication off UK administration. UK was given at a dose of 100,000 i.u. every two hours until disappearance of PE. Before and after treatment the levels of D-dimer were measured in order to monitor pleural fibrinolytic activity. The SCC was properly placed in all patients. UK administration was 366,000 i.u. and time the SCC were in place was 4.7 days. All PEs were initially drained completely. We examined the patients 30 days later, finding that PE had recurred in 2 (4%), resolution was complete and without sequelae in 8 (16%), nearly complete but with slight pleural thickening in 32 (64%) and partial with pleural opacities larger than 2 mm in 8 (16%). Use of SCC and UK (pleural fibrinolysis) is a moderately invasive procedure that is effective and well tolerated and that shortens drainage time, prevents sequelae and is relatively inexpensive for the treatment of PE with fibrin septation and/or multiloculation.

Adolescent↗
PubMed1995

Evaluation of phagocytic capacity with a modified flow cytometry technique.

Phagocytic capacity was determined in human polymorphonuclear leukocytes with a modified flow cytometry technique. The advantages of this method include simplified sample preparation--the assay is done using whole blood--and quantification of phagocytosis with a phagocytic index obtained by comparison with controls, which obviates errors arising from non-specific adherence.

Anticoagulants↗
PubMed1995

Isolation of genes differentially expressed at the downstream anastomosis of prosthetic arterial grafts with use of mRNA differential display.

PURPOSE: Downstream anastomotic intimal hyperplasia in prosthetic arterial grafts remains a major cause of delayed graft failure. The new method of messenger RNA (mRNA) differential display was used to screen numerous genes to gain insight into the molecular mechanisms of intimal hyperplasia. METHODS: Fifty-centimeter-long 8 mm expanded polytetrafluoroethylene grafts were placed in four mongrel dogs from the carotid artery to the distal abdominal aorta. At 3 months the distal anastomoses and adjacent normal aortas were harvested; a portion was taken for histologic examination, and total RNA was isolated from the remainder. Differential mRNA display was used to identify candidate cDNA clones whose expression differed in anastomotic intimal hyperplasia as compared with adjacent unaffected aorta. The clones were sequenced, and national gene databases were searched. Northern blot analysis confirmed alteration of gene expression. RESULTS: Approximately 5000 mRNA species were screened, and 11 candidate clones were obtained. DNA sequence revealed homology of five clones to known gene sequences. Homologous genes included an interferon-gamma-induced human gene, (IGUP I-5111), alpha-1 protease inhibitor gene, human retinoblastoma susceptibility gene, and human creatine kinase gene (two clones). Northern blot analysis revealed altered gene expression in 4 of 11, nonregulation in 1 of 11, and undetectable signals in 6 of 11. Expression of the clone representing IGUP I-5111 in the segment of intimal hyperplasia was found to be decreased over threefold to only 31% +/- 16.4% SE of the level seen in normal aorta. CONCLUSIONS: The technique of mRNA differential display has identified differences in gene expression in an in vivo model of anastomotic intimal hyperplasia. Expression of RNA with homology to an interferon-gamma-induced human gene was consistently decreased within the hyperplastic region at the downstream polytetrafluoroethylene arterial anastomosis.

Anastomosis, Surgical↗
PubMed1995

Constitutive secretion of interleukin-6 by human decidual stromal cells in culture. Regulatory effect of progesterone.

PROBLEM: Although several studies have demonstrated that decidual stromal cells (DSC) can secrete cytokines in culture, none of these studies documented the purity of the cultures. Since other cells of the decidua, such as macrophages and epithelial cells, also produce cytokines, it is important to ensure purity of the culture so that cytokine production can be ascribed with confidence to DSC. METHOD: DSC from early human pregnancies were highly purified and maintained in culture. Basal secretion by these cells of IL-6, together with other cytokines considered critical for pregnancy (IL-1 beta, TNF alpha and IFN gamma), was measured with immunological techniques. RESULTS: We found that DSC in culture produce insignificant quantities of IL-1 beta, TNF alpha and IFN gamma, but appreciable amounts of IL-6. The production of this later cytokine was, however, inhibited by the effect of progesterone. CONCLUSIONS: Basal production of IL-6 by DSC may be involved in physiological functions at the maternal-fetal interface. Nevertheless, the secretion of this cytokine is regulated by progesterone, probably to prevent excessive production of this cytokine from triggering an inflammatory response that might compromise pregnancy.

Antigens, CD↗
PubMed1995

Relationship of blood rheology to lipoprotein profile during normal pregnancies and those with intrauterine growth retardation.

AIMS: The effects on fetal growth of hyperlipidaemia in pregnancy are not well understood at present. In this study the different lipid fractions in normal pregnancies and pregnancies complicated by intrauterine growth retardation (IUGR) were determined and related to changes in plasma and serum viscosity. METHODS: Two groups of pregnant women were studied. Group 1 consisted of 35 healthy pregnant women aged between 21 and 38 years with no previous pathology and a normal pregnancy to term. Group 1 patients were studied at four periods defined at the start of the study: (1) < or = 17 weeks; (2) 18-24 weeks; (3) 25-32 weeks, (4) > or = 33 weeks. Group 2 consisted of 24 pregnant women aged between 16 and 34 years with ultrasound diagnosed IUGR confirmed after birth. Plasma lipids and plasma and serum viscosity were measured. RESULTS: Plasma triglycerides, low density lipoprotein cholesterol, and total cholesterol increased progressively throughout pregnancy, with significantly higher values after week 25. Apolipoprotein A (ApoA) and triglyceride concentrations were significantly lower in the IUGR group than in the normal group. The HDL/ApoA ratio was greater in the IUGR group than in the control group, as was the ApoB/ApoA ratio. There were no differences in the other lipids. Plasma and serum viscosity was higher in the IUGR group than in the normal group. CONCLUSIONS: Haemorheological modifications in the IUGR group are partly secondary to changes in high density lipoprotein metabolism and the competitive inhibition of fibrinolysis by ApoB, which is increased in pregnancies with IUGR. Changes in ApoA, and more specifically in the ApoB/ApoA ratio, could be good markers for the early detection of IUGR.

Adolescent↗
PubMed1995

Sequential gene activation by ecdysone in Drosophila melanogaster: the hierarchical equivalence of early and early late genes.

Ecdysteroids are key regulators of insect development. In Drosophila melanogaster the late larval response to ecdysone is characterised by a precise sequential activation of members of the superfamily of nuclear receptors (DHR3, DHR39, EcR, E75, E78, FTZ-F1, usp). Many of these genes are localised in the polytene chromosome puffs of the salivary gland previously classified as intermoult, early or early-late puff loci. Ashburner et al. (Ashburner, M., Chihara, C., Meltzer, P. and Richards, G. (1974) Cold Spring Harbour Symp. Quant. Biol. 38, 655-662) proposed a formal model describing interactions between ecdysone, its receptor and the early and late puffs during this ecdysone response. To integrate transcripts from the intermoult and early-late puffs into this model, we have used a micro RT-PCR assay to study their hormonal regulation using salivary gland culture protocols first used in the puffing analyses. We show that transcripts from certain early-late puffs are induced in parallel with the early transcripts and are thus hierarchically equivalent. In vivo the profile of the increase in hormone titre, the sensitivity of different promoters to hormone and the rate of transcript accumulation must contribute to the temporal differences in expression observed between these two classes.

Animals↗
PubMed1994

[Changes in the cerebral flow velocity induced in the middle cerebral artery by acute stress studied by transcranial Doppler ultrasonography].

BACKGROUND: The behavior of brain flow on acute stress has not been previously evaluated. Transcranial Doppler ultrasonography (TD) is a bloodless method to evaluate the speed of cerebral flow in the arteries of the Willis polygon. The present study was designed to analyze the changes which occur in the same during two situations of acute stress. METHODS: The mean speed of cerebral flow (MS) and the pulsation rate (PR) of the right and left middle cerebral artery (MCA) were measured basally and following a mental stress test (calculation) and physical stress (cold test) by TD and through the temporal window. Twenty-five healthy volunteers (18 women and 8 men) with a mean age of 27.8 +/- 7.3 years were studied. RESULTS: In response to mental stress an increase was observed in MS in both the right MCA (10 +/- 8.6 cm/sec) and the left MCA (10.4 +/- 8.7 cm/sec) with a decrease in the MCA (0.14 +/- 0.23 in the right MCA, 0.14 +/- 0.18 cm/sec in the left MCA). In response to the cold test an increase in MS (7.3 +/- 7.5 cm/sec in the right MCA, 14.8 +/- 14.7 cm/sec in the left MCA) was also observed with a decrease in the PR (0.2 +/- 0.2 in the right MCA and 0.2 +/- 0.16 in the left MCA). No significant differences were observed in the changes induced in the right or left artery or in those induced by the mental or cold tests. CONCLUSIONS: These results suggest that the acute stress produces an increase in cerebral flow in the arteries of the Willis polygon.

Adult↗
PubMed1994

Triploid partial molar pregnancy detected through maternal serum alpha-fetoprotein and HCG screening.

BACKGROUND: Screening for Down syndrome using maternal serum alpha-fetoprotein (MSAFP) and hCG, with or without unconjugated estriol (E3), has become standard practice in much of the United States. When both MSAFP and hCG are elevated, the possibility of a partial molar pregnancy with fetal neural tube or abdominal-wall defect should be added to the differential diagnosis, as illustrated by this case. CASE: A 22-year-old woman had elevated MSAFP and hCG levels on routine screening at 16 weeks' gestation. Ultrasound examination suggested a neural tube defect and a thickened placenta. Amniocentesis was performed. She very rapidly developed preeclampsia. Fluorescence in situ hybridization showed three distinct spots for the three probes tested. A triploid karyotype was confirmed with standard cytogenetic analysis. The fetus had an open neural tube defect, and placental pathology was consistent with a partial hydatidiform mole. CONCLUSIONS: A possible partial molar pregnancy with abdominal-wall or open neural tube defect should be added to the differential diagnosis for interpreting Down syndrome screens when both MSAFP and hCG are elevated. A presumptive diagnosis of triploidy using fluorescence in situ hybridization was important in the management of this pregnancy.

Adult↗
PubMed1994

Dose-dependent effects of transdermal nicotine on early morning awakening and rapid eye movement sleep time in nonsmoking normal volunteers.

The dose-dependent, acute effects of transdermal nicotine (7 and 14 mg) and placebo, applied 2 hours before bedtime, on sleep and mood were determined in 12 nonsmoking normal volunteers. Compared with placebo patch, transdermal nicotine was associated with early morning awakening and reduced total rapid eye movement (REM) sleep time and REM% in a dose-dependent fashion. On the recovery night after the administration of an active nicotine patch, REM latency and stage 2% were significantly reduced, whereas REM sleep time and REM% increased compared with the active patch. Mood and subjective recall of dreaming were not significantly affected in this study. Although one subject vomited about 10.5 hours after the 14-mg dose, reported side effects were generally mild.

Administration, Cutaneous↗
PubMed1993

Holzgreve syndrome: recurrence in sibs.

We report on 2 sibs with cardiac and renal abnormalities. The first had hypoplastic left heart sequence and renal hypoplasia; the second had a complex congenital heart defect, renal agenesis, and cleft lip and palate. We suggest that these cases represent the first familial examples of the Holzgreve syndrome. As such, they demonstrate the phenotypic variability seen in sibs, and may serve to further delineate the syndrome.

Abnormalities, Multiple↗
PubMed1993

The cholinergic REM sleep induction test with pilocarpine in mildly depressed patients and normal controls.

Previous studies suggested that depressed patients enter rapid-eye movement (REM) sleep more quickly than normal controls following the administration of muscarinic agonists such as arecoline or RS 86. We recently reported that pilocarpine, an orally active muscarinic agonist, induced REM sleep and reduced Stage 3 & 4 (Delta) sleep in young normal volunteers. In this study we present preliminary evidence that pilocarpine had similar effects on REM latency, REM percentage, and Delta (Stages 3 & 4) sleep percentage in depressed patients and controls. Pilocarpine, however, decreased stage-4 sleep in controls more than in depressed patients. Because this group of patients were only mildly depressed at the time of the study, had a high frequency of comorbid substance abuse diagnoses, and had normal electroencephalogram (EEG) sleep patterns under placebo conditions, further studies are necessary to test the hypothesis that depressed patients show hypersensitive cholinergic REM sleep induction.

Adult↗
PubMed1993

Expression of adhesion molecules by endothelial cells of early human decidua.

The expression of adhesion molecules by endothelial cells (EC) of early human decidua was studied with monoclonal antibodies and the immunoperoxidase technique. Although E-selectin, INCAM-110 and VCAM-1 were poorly detected on decidual EC, ICAM-1, P-selectin and DR antigens were highly expressed by these cells, some of which showed high endothelial venule-like morphology. Our results suggest that decidual EC are activated, and are probably involved in the active recruitment of leucocytes.

Cell Adhesion Molecules↗
PubMed1993

Cardiovascular reflexes in Parkinson disease.

We have investigated the autonomic function of 95 patients with Parkinson disease (PD) by testing their cardiovascular reflexes and compared the results with those of 53 healthy volunteers. 51.1% of the patients were on antiparkinsonian therapy. The patients showed a smaller heart rate response to deep breathing with a mean exhalation-inspiration difference of 87.73 +/- 7 (p: 0.0005), a smaller heart rate response to standing with a mean 30: 15 index of 1.18 +/- 0.25 (p: 0.01), and a smaller blood pressure rise to handgrip with a mean rise of 9.53 +/- 8.76 mmHg (p: 0.005). We found a higher percentage of patients with established sympathetic lesion (41% vs 34%) or atypical patterns of global autonomic function involvement (33% vs 26%), but the percentage of subjects with parasympathetic lesion was similar in both, patients and controls (16% vs 15%). We found no significant difference on cardiovascular performance between treated and untreated patients. The patients with autonomic impairment were older than the patients with normal autonomic function. Our findings suggest that patients with PD have a true autonomic dysfunction.

Adult↗
PubMed1993

Expression of class II HLA molecules by endothelial cells of human decidua.

Many authors have documented a high level of expression of class II HLA molecules by decidua. Although macrophages appear to be responsible for this, we show in this article that endothelial cells (EC) of the venules and capillaries of human decidua also strongly express class II molecules, whereas EC of chorionic villi do not. We discuss this finding in the context of the maternal-fetal immune interaction.

Arterioles↗