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Biomedical subjects

A Dumont

Publications and source records attributed to A Dumont.

At least 37 records · Page 2Linked to original sources
PubMed1999

Effect of aspirin in pregnant women is dependent on increase in bleeding time.

OBJECTIVES: Randomized trials with low-dose aspirin to prevent preeclampsia and intrauterine growth restriction have yielded conflicting results. In particular, 3 recent large trials were not conclusive. Study designs, however, varied greatly regarding selection of patients, dose of aspirin, and timing of treatment, all of which can be determinants of the results. Retrospectively analyzing the conditions associated with failure or success of aspirin may therefore help to draw up new hypotheses and prepare for more specific randomized trials. STUDY DESIGN: We studied a historical cohort of 187 pregnant women who were considered at high risk for preeclampsia, intrauterine growth restriction, or both and were therefore treated with low-dose aspirin between 1989 and 1994. Various epidemiologic, clinical, and laboratory data were extracted from the files. Univariate and multivariate analyses were performed to search for independent parameters associated with the outcome of pregnancy. RESULTS: Age, parity, weight, height, and race had no influence on the outcome. The success rate was higher when treatment was given because of previous poor pregnancy outcomes than when it was given for other indications, and the patients with successful therapy had started aspirin earlier than had those with therapy failure (17.7 vs 20.0 weeks' gestation, P =.04). After multivariate analysis an increase in Ivy bleeding time after 10 days of treatment by >2 minutes was an independent predictor of a better outcome (odds ratio 0.22, 95% confidence interval 0.09-0.51). Borderline statistical significance was observed for aspirin initiation before 17 weeks' gestation (odds ratio 0.44, 95% confidence interval 0.18-1. 08). Abnormal uterine artery Doppler velocimetric scan at 20-24 weeks' gestation (odds ratio 3.31, 95% confidence interval 1.41-7.7), abnormal umbilical artery Doppler velocimetric scan after 26 weeks' gestation (odds ratio 37.6, 95% confidence interval 3.96-357), and use of antihypertensive therapy (odds ratio 6.06, 95% confidence interval 2.45-15) were independent predictors of poor outcome. CONCLUSIONS: Efficacy of aspirin seems optimal when bleeding time increases >/=2 minutes with treatment, indicating a more powerful antiplatelet effect. This suggests that the dose of aspirin should be adjusted according to a biologic marker of the antiplatelet effect. A prospective trial is warranted to test this hypothesis.

Adult↗
PubMed1998

Tumor necrosis factor-alpha-induced cell killing and activation of transcription factor NF-kappaB are uncoupled in L929 cells.

The induction of transcription factor NF-kappaB has been shown to counteract tumor necrosis factor (TNF)-alpha-induced cell death in various cell types. In this study, we investigated the role of NF-kappaB for TNF-alpha-triggered cell death in the widely used mouse cell line L929 by various approaches. Inhibition of the mitochondrial permeability transition by bongkrekic acid impaired TNF-alpha-induced cell death without affecting the activity of NF-kappaB. The reduction of NF-kappaB-mediated gene expression by the synthetic steroid dexamethasone was associated with a decrease in TNF-alpha-mediated cell killing, suggesting that NF-kappaB does not protect L929 cells from TNF-alpha-induced cell death. This concept was reinforced by experiments employing L929 cell lines stably overexpressing a transdominant negative form of IkappaB-alpha. These cell lines were unable to activate NF-kappaB and to inducibly express the IL-6 gene, but they showed the same susceptibility toward TNF-alpha-mediated cell death as L929 wild-type cells.

Animals↗
PubMed1998

Co-stimulatory effect of nitric oxide on endothelial NF-kappaB implies a physiological self-amplifying mechanism.

Here we investigated the effects of the second messenger molecule NO at various concentrations on the activation of transcription factor NF-kappaB, IkappaB-alpha kinase (IKK-alpha), Jun N-terminal kinase (JNK) and apoptosis in murine endothelial cells. Low concentrations of NO alone failed to activate NF-kappaB, IKK-alpha and JNK. When NF-kappaB was prestimulated by TNF-alpha or phorbol 12-myristate 13-acetate, the addition of NO at low concentrations enhanced the activation of NF-kappaB. This provides a mechanism for a self-amplifying signal in the inflammatory response, since the inducible NO synthase in endothelial cells is regulated by NF-kappaB. The co-stimulatory effect of NO on NF-kappaB activation was also evident from IKK-alpha kinase assays and reporter gene experiments in endothelial cells. High doses of NO impaired the TNF-alpha-induced DNA-binding activity of NF-kappaB. Accordingly, these high amounts of NO also repressed the TNF-alpha-induced transactivation by NF-kappaB as efficient as dexamethasone. The doses of NO required for the inhibition of NF-kappaB are not cytotoxic for the endothelial cells, enabling the establishment of an autoregulatory loop for NF-kappaB signaling.

Animals↗
PubMed1997

Longitudinal survey of voice quality after pediatric laryngotracheoplasty.

This study assesses the effect of pediatric laryngotracheoplasty on voice quality. A group of ten children who underwent laryngotracheoplasty with thyrotomy and anterior cartilage graft were examined two or more times after decannulation and their voices were compared to those of sex- and age-matched controls. Each examination included a laryngoscopy, evaluation by a speech/language pathologist and measurement of maximum phonation times and fundamental frequencies using the Signalyse program. The strength of the voices and the maximum phonation times gradually improved. The fundamental frequency became lower with age, as in the controls. The data suggest that laryngotracheoplasty does not hamper the development of voice with age in children and that the voice improves without any further surgery, although hoarseness remains.

Adolescent↗
PubMed1997

Methodological validation and clinical usefulness of carbon-14-urea breath test for documentation of presence and eradication of Helicobacter pylori infection.

UNLABELLED: A simple [14C]urea breath test (C-14-UBT) was validated with aims of determining accuracy in documenting both the presence and proof of eradication of Helicobacter pylori infection. METHODS: Fifty-six dyspeptic patients had endoscopy with biopsies and C-14-UBT. Eleven biopsy-proven H. pylori-negative patients allowed C-14-UBT normal value determination. Forty-three patients with recurrent peptic ulcer disease and biopsy-proven H. pylori infection were included in an antimicrobial eradication protocol. Endoscopy with biopsies and C-14-UBT were done again 8 wk after initiation of treatment in 35 patients. For C-14-UBT, 185 kBq (5 microCi) of [14C]urea was swallowed. Breath samples obtained up to 20 min were counted to calculate AS20, [(% 14CO2 dose excreted/mmol of CO2) x kg] at 20 min. Combined histologic and microbiologic analyses of antral biopsies were used as a gold standard. RESULTS: The positivity value was set as AS20 > 0.33% (mean + 3 s.d. of AS20 in H. pylori-negative patients). Diagnosis of H. pylori infection was correct with C-14-UBT in 55/56 patients (44 true-positive, 11 true-negative and 1 false-negative; sensitivity = 98%; specificity = 100%). As a proof of eradication, C-14-UBT correctly classified 33/35 patients (5 true-positive, 28 true-negative and 2 false-positive; sensitivity = 100%; specificity = 93%). The C-14-UBT global performance yielded sensitivity, specificity and accuracy of 98%, 95% and 97%, respectively. A significant correlation (r = 0.84) was found between AS20 and the number of H. pylori colonies on culture. CONCLUSION: This C-14-UBT is highly accurate both for diagnosis and proof of eradication of H. pylori infection and reflects the antral bacterial load. It is simple, fast and inexpensive, and it is therefore suitable for clinical practice.

Breath Tests↗
PubMed1997

[Severe preeclampsia: management. Is conservative treatment justified?].

Severe preeclampsia is a major contributor to maternal and perinatal morbidity and mortality. This review was performed to assess the fetal and maternal benefits of allowing women presenting with severe preeclampsia between 24 and 32-34 weeks of amenorrhea to continue their pregnancy following antihypertensive treatment. After ultrasound scanning to assess growth and biophysical state of the fetus, patients without deteriorating maternal conditions, were managed with volume expansion, antihypertensive drugs (as hydralazine, labetalol, nifedipine), anticonvulsants and prophylactic steroids to promote fetal pulmonary maturity. Previous studies have indicated that this conservative management is also possible with the HELLP syndrome, without an increase in maternal morbidity.

Anticonvulsants↗
PubMed1996

Clinical comparison of three labeled-antibody immunoassays of free triiodothyronine.

Three labeled-antibody immunoassays of free triiodothyronine (FT3) were studied in hyperthyroid patients, patients with nonthyroidal illness, and patients being treated with amiodarone; we also studied sera presenting known interferences (n for all groups = 465). The results were compared with those of a one-step labeled-analog assay. The precision of the two automated assays were similar to that of the manual assays. The three labeled-antibody FT3 assays demonstrated a satisfactory diagnostic performance for confirming hyperthyroidism and robustness to interference; nevertheless, two assays displayed unusual behavior in some patients with nonthyroidal illness, with chronic renal failure, or after amiodarone therapy.

Adolescent↗
PubMed1996

[Vaginal cesarean for fetal deaths in utero].

Among a series of 100 cases of retroplacental hematomas we performed vaginal cesareans in 15 and present here the technical difficulties, solutions and indications of this procedure in case of in utero fetal death. Criteria for choosing vaginal cesarean were: term les than 32 weeks, biparietal diameter > 80 mm, fetal weight < 2500 g. The main difficulty was the disproportion between the size of the fetus and the cervical orifice due to insufficient anterior trachelotomy. Possible solutions are posterior trachelotomy or craniotomy. This procedure is rapid and causes little blood loss and important advantage in case of impaired hemostasis.

Adult↗
PubMed1995

Steindler and pectoralis major flexorplasty: a comparative analysis.

Previously published studies on transfers to restore elbow flexion have rarely compared the outcomes among different techniques. We found no comparison between the Steindler procedure and pectoralis major tendon transfer. This study compared functional outcomes after these two types of elbow flexorplasty performed in conjunction with shoulder arthrodesis for patients with brachial plexus injuries. The same examiner assessed 14 patients who underwent shoulder fusion and elbow flexorplasty. Five had a pectoralis major tendon transfer, and nine underwent a modified Steindler procedure. All patients had brachial plexus lesions that were irreparable or had not responded to neurolysis, repair, or grafting. Average follow-up time was 60 months (range, 12 months-10 years). All patients completed a questionnaire (pain, function) and underwent an objective assessment of range of motion, isometric strength, isotonic power, grip, and pinch strength. The BTE Work Simulator (Baltimore Therapeutic Equipment, Hanover, MD) was used for muscle strength testing. Improvement was noted in daily activities including dressing and bilateral activities and was reflected in a significant improvement over preoperative function. No differences (at p = .05 level of significance) were found in objective tests between the pectoralis major transfer and the Steindler groups. In the patient requiring stabilization of the shoulder and flexorplasty, the pectoralis major tendon transfer was at least equivalent to the modified Steindler flexorplasty in terms of range of motion, strength, and subjective measures.

Activities of Daily Living↗
PubMed1995

[Scintigraphy of iodine 123 labelled serum amyloid P component in beta 2-microglobulin amyloidosis of hemodialysis].

UNLABELLED: To assess the iodine-123-labelled serum amyloid P component (SAP) scintigraphy in patients with haemodialysis-associated amyloidosis. PATIENTS: Eight patients with histologically proven beta 2-microglobulin amyloidosis. METHODS: Purified SAP was iodinated by a modified iodogen method. Whole body data were acquired with a large rectangular field gamma-camera. RESULTS: In 7 cases, articular uptake was observed in the symptomatic joints (shoulders, wrists, knees) or in view of bone cysts (wrists). Among the 3 patients with erosive arthropathy of the hands, only one had positive scintigraphy. None positive scintigraphic image was obtained in the spine or the hip joint. In one patient with multifocal amyloid joint disease, no positive image was noted. No abnormal visceral uptake was observed and particularly of the spleen except in one patient with liver uptake. CONCLUSION: I-123 SAP scintigraphy might be not very sensitive in diagnosing beta 2 amyloid deposits. This method needs further investigations and particularly in patients undergoing haemodialysis for more than 20 years.

Aged↗
PubMed1994

Spatial distribution of DNA ploidy in colorectal carcinoma.

This paper reports on the phenomenon of heterogeneity of DNA distribution in colorectal carcinoma. The aim of this study was to find a new strategy in sampling methodology as a solution to the heterogeneity problem by studying ploidy topography. The study was carried out by using image analysis for densitometric measurements of tissue imprints of 19 colorectal specimens after Feulgen staining. Heterogeneity of ploidy in colorectal carcinoma is well known; therefore, we wished to determine whether this heterogeneity is random within different parts of a colorectal tumour. For each tumour, five systematic and reproducible samples were taken from the peripheral, intermediate and central tumoural areas. In addition two samples were taken from adjacent non-tumoural areas: one from the proximal and the other from the distal site with respect to the neoplastic lesion. By using image analysis three parameters were obtained. Mean DNA content was computed for each sample and expressed in arbitrary units (DNA-a.u.) from the measurement of integrated optical density according to the Beer Lambert law. Secondly mean DNA content expressed in relative units (DNA-r.u.) was computed according to an internal euploid control. Finally entropy was computed from each histogram of DNA content. Experimental design was based on a repeated measures analysis of variance with a priori orthogonal comparisons. We found that DNA content and particularly entropy are not randomly distributed. Furthermore, there was a significant difference between the two non-tumoural epithelia.

Colorectal Neoplasms↗
PubMed1994

Changing patterns of scaphoid fractures in adolescents.

OBJECTIVE: To determine if the presentation of scaphoid fractures in children has changed. DESIGN: Case study with a minimum follow-up of 1 year. SETTING: Outpatient orthopedic clinic in an urban pediatric hospital. PATIENTS: Twenty-one adolescents (mean age 13.9 years) with scaphoid fractures and an open distal radial growth plate. Fracture healing was assessed at 2-week intervals until union was achieved. INTERVENTIONS: Immobilization in a short-arm thumb spica cast. MAIN OUTCOME MEASURES: Fracture union as defined by the absence of pain and obliteration of the fracture line. Active and passive range of motion of wrist as measured with a goniometer. RESULTS: Only 2 of the 21 patients had avulsed fractures. Twelve fractures were located in the middle one-third of the scaphoid. All fractures healed, but two fractures were in a dorsiflexed position. All patients had full, painless range of wrist motion. No arthrosis was present. CONCLUSIONS: The presentation of scaphoid fractures in adolescents has changed over the years and now resembles the adult pattern. Malunited scaphoid fractures may be seen. Displaced fractures should be reduced.

Accidental Falls↗
PubMed1993

[Neurotoxic role of glycocolle and derivatives in transurethral resection of the prostate].

72-year-old patient underwent an elective transurethral resection of the prostate (TURP) performed with a spinal anaesthesia. The irrigation solution contained glycine at a concentration of 15 g.l-1. The patient's level of consciousness deteriorated over the next 4 hours. He went in an areflexic coma with pupillary areflexia and left mydriasis. The diagnosis of TUR syndrome was substantiated by a sodium blood concentration of 98 mmol.l-1, an osmotic gap of 48 mosmol.kg-1 and blood ammonia at 415 mumol.l-1. To investigate the pathophysiological role of glycine and its metabolites, their concentrations were measured by chromatography and spectrometry in plasma and CSF 8, 24 and 48 hours postoperatively. Glycine and its metabolites (serine, alanine, glyoxylic acid and glycolic acid) accumulated during the postoperative period in both blood and CSF. The central nervous system is in direct contact with these neurotropic compounds. Glycine is an inhibitory neurotransmitter, whereas glyoxylic acid and glycolic acid are considered as to be neurotoxic.

Aged↗
PubMed1992

Prevention of nosocomial pneumonia in intubated patients: respective role of mechanical subglottic secretions drainage and stress ulcer prophylaxis.

Chronic microaspiration through a tracheal cuff is the main culprit in the penetration and colonization of the lower respiratory tract. A total of 145 patients intubated for more than 3 days were randomly assigned to a double nosocomial pneumonia (NP) prevention: 1--Prevention of aspiration by hourly subglottic secretion drainage (SSD) with a specific endotracheal tube (HI-LO Evac tube, Mallinckrodt); 2--Prevention of gastric colonization using either sucralfate or antacids. Four random groups were defined, similar in age and severity of illness. Subglottic secretion drainage treatment was associated with: a) a twice lower incidence of NP (no-SSD: 29.1%, SSD: 13%); b) a prolonged time of onset of NP (no-SSD: 8.3 +/- 5 days, SSD: 16.2 +/- 11 days); c) a decrease in the colonization rate from admission to end-point day in tracheal aspirates (no-SSD: +21.3%, SSD: +6.6%) and in subglottic secretions (no-SSD: +33.4%, SSD: +2.1%). Sucralfate was not associated with a significantly lower incidence of NP (antacids: 23.6%, sucralfate: 17.8%), but with a lower increase in the colonization rate in subglottic and gastric aspirates, from admission to end-point day.

Adult↗
PubMed1991

Short- and long-term prognosis, functional outcome following ICU for elderly.

Among 1532 ICU patients we analysed 295 elderly patients (19%) aged more than 70-years-old. We determined prospectively the immediate and subsequent one-year outcome with a study of the predictive value of their ICU admission parameters. Then we followed the ICU survivors over the year after discharge (1, 6, 12 months) by quality of life questionnaires. ICU mortality was 26.7%; SAPS was the only predictor of short term mortality. On ICU discharge, 216 elderly were followed at 1, 6, 12 months; the one-year cumulative mortality was 49% from ICU discharge, majority of deaths occurring over the first month. Age, previous health status and SAPS had a predictor value of one-year mortality for ICU survivors. 103 patients were alive at one year: 88% returned to home, 72% had a relatively good functional status allowing an independent life, and 82% had the same or improved functional status.

Activities of Daily Living↗