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Biomedical subjects

B Denis

Publications and source records attributed to B Denis.

At least 19 recordsLinked to original sources
PubMed1999

Characterization of permissivity for hobo-mediated gonadal dysgenesis in Drosophila melanogaster.

The hobo transposon is responsible for one of the three hybrid dysgenic systems that have been described in Drosophila melanogaster. Most studies on the hobo dysgenic system have been carried out using the PM system as a reference. However, these two systems differ significantly. In particular, several studies have failed to find any correlation between the molecular structures of hobo elements, the instability of the transposon and the incidence of gonadal dysgenic (GD) sterility. On the other hand, no study of the ability of females to permit hobo activity in their progeny when they are crossed with males harboring active hobo elements (permissivity) has yet been reported. In order to investigate the parameters involved in hobo permissivity, four E strains were studied with regard to the molecular nature of their hobo sequences and the GD sterility induced by a controlled source of hobo transposase. We show that hobo permissivity varies both within and between E strains. Moreover, permissivity decreases with age in E females. Our results are discussed with respect to similar phenomena that have been described in relation to the reactivity of the IR dysgenic system.

Aging↗
PubMed1999

Prediction of cardiovascular events in clinically selected high-risk NIDDM patients. Prognostic value of exercise stress test and thallium-201 single-photon emission computed tomography.

OBJECTIVE: We evaluated the prognostic value of an exercise stress test and thallium-201 scintigraphy for the prediction of cardiac events in selected high-risk NIDDM patients. RESEARCH DESIGN AND METHODS: NIDDM patients (n = 158, 105 men, aged 63 +/- 9 years) with two or more of the following criteria were prospectively included: age > or = 65 years, active smoking, hypertension > 160/95 mmHg, hypercholesterolemia (cholesterol > 5.70 mmol/l or LDL > 3.10 mmol/l), peripheral artery disease, abnormal rest electrocardiogram, or microalbuminuria (20-200 micrograms/min). An exercise-stress scintigraphy was performed in 77 patients able to exercise, while a dipyridamole scintigraphy was performed in 80 patients unable to exercise. Follow-up was 23 +/- 17 months. Major end points were cardiac deaths or nonfatal myocardial infarction. RESULTS: The annual event rate was 7.31% (deaths: 8, myocardial infarction: 14). Independent predictors of events were as follows: an age > 60 (P = 0.02), an abnormal rest electrocardiogram (P = 0.02), microalbuminuria (P = 0.001), the inability to exercise (P = 0.009), and the presence of more than two defects on scintigraphy (P = 0.001). A cardiac death occurred in 1.3% of patients able to exercise versus 8.8% of patients unable to exercise (odds ratio = 6.8, P = 0.001). Among patients unable to exercise, large perfusion defects corresponded to an annual mortality rate of 22.3%. Conversely, the negative predictive value of a normal scintigraphy for the occurrence of death was 97%. CONCLUSIONS: Inability to exercise and large perfusion defects on thallium-201 scan are major predictors of future death and myocardial infarction in high-risk NIDDM patients.

Activities of Daily Living↗
PubMed1998

Arrhythmic cardiac arrest due to isolated coronary artery spasm: long-term outcome of seven resuscitated patients.

OBJECTIVES: Our aim was to look at the clinical features and long-term follow-up of seven patients without coronary artery disease, who had a history of life-threatening ventricular arrhythmias due to coronary spasm. BACKGROUND: Arrhythmic cardiac arrest due to isolated coronary spasm is rare, and there is limited information on the patients affected by this entity alone. METHODS: The seven patients were recruited retrospectively from a cohort of survivors of cardiac arrest. None had a history of angina pectoris, structural heart disease or significantly narrowed coronary segments. All had a positive ergonovine provocation test result. RESULTS: The patients' mean age was 44 years; three were male and four female. All were habitual cigarette smokers. No arrhythmias were induced on programmed ventricular stimulation; corrected QT interval (QTc) and corrected JT interval (JTc) dispersion were within normal ranges. After the ergonovine provocation test, treatment with calcium channel blocking agents (diltiazem, verapamil, nifedipine or amlodipine) was initiated at a dose determined by titration until a negative test result was obtained. At a mean follow-up interval of 58 months for the total group, six patients remained free of symptoms, whereas the one patient who did not stop smoking had a new cardiac arrest despite treatment for coronary spasm. CONCLUSIONS: A favorable long-term outcome may be expected in survivors of cardiac arrest due to coronary spasm, in the absence of significant coronary artery disease. Calcium channel blockers are the most appropriate therapy in these patients. These observations provide further evidence for the role of silent ischemia in cardiovascular death.

Adult↗
PubMed1997

[A rare cause of inappropriate shocks of an implantable automatic defibrillator. Twiddler syndrome].

The authors report the case of a patient with an automatic defibrillator implanted by an endocavitary approach. The device emitted a series of inappropriate shocks. They were triggered by the detection of myopotentials resulting from lesions of the lead due to Twiddler's syndrome. This was reproduced by telemetry in real time and confirmed by chest and abdominal X-ray and the peroperative findings. Treatment consisted of ablation of all implanted material which was replaced by a new retropectoral model.

Electrocardiography, Ambulatory↗
PubMed1996

[Outcome of cardiac valve ring abscesses after medical treatment: attempt to identify criteria of favorable prognosis].

OBJECTIVES: Identify factors predicting favorable outcome after medical management of valve ring abscesses in order to propose a surveillance schedule for conservative treatment. METHODS: A multicentric study conducted from July 1989 to February 1996 included 28 patients (mean age 64 +/- 16 years, range 26-83) hospitalized for active endocarditis and valve ring abscesses diagnosed at transthoracic or transesophageal echography. Conservative medical therapy was given because of a decision of the medico-surgical team (n = 9), high surgical risk (n = 12), or patient refusal of surgery (n = 7). Outcome was favourable in 18 patients (Group I) and unfavorable in 10 (Group II) due to death (n = 9) or subsequent surgery (n = 1). Univariate and multivariate analysis were used to determine differences between the groups in terms of clinical and laboratory data. RESULTS: Mean follow-up in Group I was 33 +/- 18 months and 15 +/- 10 months in Group II. Univariate analysis showed significant differences between Group I and II respectively for age (59 +/- 18 yr vs 72 +/- 10, p = 0.04), delay to apyrexia after antibiotics (4.3 +/- 2.8 vs 8.3 +/- 2.4 days, p < 0.0008), heart failure (5% vs 70%, p = 0.003), grade III or IV valvular regurgitation (5% vs 60%, p < 0.04), and mean surface area of the abscess (1.5 +/- 1.2 vs 5.4 +/- 6.4 cm2, p < 0.03). Independent factors at multivariate analysis were by decreasing order: lack of heart failure at admission, delay to apyrexia, abscess surface area, and age. Outcome was favorable (mean follow-up 33 +/- 10 months) in all patients with an abscess surface area < 1.5 cm2, no signs of heart failure, no grade III or IV valvular regurgitation, apyrexia after less than 8 days on antibiotics and no staphylococcus positive blood culture. CONCLUSION: Medical management of valve ring abscesses may be indicated in selected patients in care units with rigorous surveillance facilities. Further studies are needed to precisely identify surveillance and treatment criteria.

Abscess↗
PubMed1996

Plasma and erythrocyte manganese concentrations. Influence of age and acute myocardial infarction.

This study was carried out to assess manganese (Mn) status after an acute episode of myocardial infarction. Plasma and erythrocyte Mn concentrations were measured from admission to hospital to day 15 postadmission in 21 patients suffering from acute myocardial infarction and in three control groups. The determination of Mn in these biological fluids was performed by electrothermal atomic absorption spectrometry. Plasma Mn was higher (p < 0.01) and erythrocyte Mn was similar in the acute myocardial infarction group compared to healthy age-matched control group. Plasma and erythrocyte Mn remained unchanged during the 2 wk after acute myocardial infarction and were not correlated to enzyme activities. A decrease of erythrocyte Mn with age, expressed in nmol/L, was noted (p < 0.02). These results suggest that plasma and erythrocyte Mn do not provide an indication of myocardial damage. Nonetheless, Mn status in elderly merits further attention.

Adult↗
PubMed1996

[Left ventricular diastolic function: value of its study with mitral and pulmonary venous Doppler phonocardiography and apexography].

The study of mitral flow and pulmonary venous flow by Doppler provides a non-invasive method of assessing diastolic function. But there are difficulties in differentiating normal pattern from "pseudo-normal" (Appleton Type II) (E/A Mitral > 1). Phonocardiography enables the recording of early (B3) and late (B4) diastolic gallops. The apexogramme enables calculation of the a/H and D/H ratios (amplitude of the "D" wave resulting from rapid early diastolic filling to the total amplitude of the apexogramme). These two techniques record pulsatile phenomena ("pulse waves") arising from variations in intra-left ventricular pressure. They may complete the interpretation of Doppler recordings of velocities of blood flow ("flow waves"). To evaluate the value of each technique, the authors studied left ventricular diastolic function by Doppler phonocardiography and apexography in 60 subjects (38 patients of which 30 with ischaemic heart disease, and 22 healthy subjects). The results showed that increase in velocity and deceleration slope of the Doppler mitral E wave was associated with the presence of a B3 and correlated (r = 0.60; p = 0.0001) with the D/H ratio of the apexogramme. On the other hand, the absence of correlation between the mitral A wave velocity and a B4 associated with an increased a/H ratio enables the differentiation of normal Doppler mitral flow (absence of B4, Doppler a/H ratio < 12%) from pseudo-normal appearances (B4, a/H ratio > 12%). Therefore, the evaluation of diastolic function by Doppler mitral and pulmonary venous flow analysis may be usefully completed by phonocardiography and apexography.

Adult↗
PubMed1996

[Radiologic aspects of endoscopic sphincterotomy complications].

Endoscopic sphincterotomy (ES) is a minimally invasive technique which is the standard of reference in many clinical situations (e.g distal choledocolithiasis, recurrent lithiasis or bile duct stenosis). Complication are rare but are often misdiagnosed although radiological aspects are demonstrative. The purpose of this study is to illustrate the patterns of the complications. Ten patients have been treated for the last four years in our institution for ES complications. There were eight cases of pancreatitis, three of which had associated perforation, one arterioportal fistula, and one isolated perforation. Diagnosis was reached with CT in all but one case. Two patients have been successfully treated with percutaneous treatment (one embolization with Gianturco coils, and one drainage). Two patients died, one of necrotizing pancreatitis and the second of decubitus complication. The other patient were followed with CT. We give exemples of different observations and discuss their follow up. The severity and extent of post ES pancreatitis were readily assessed by CT and response to therapy monitored by serial examinations. Severity of disease, evaluated according to the length of hospitalization, correlated well with the presence and degree of pancreatic necrosis. CT also highlights perforations including minimal effusions. In our study differential diagnosis between post ES pancreatitis and perforation is not significant regarding the initial conservative therapy in both situations. CT scan helps us to opt for a surgical decision or for a percutaneous drainage. It also permits to follow the evolution of the lesions. In our cases involving perforations, we noted a spontaneous complete resolution of gas effusion on control and we also observed that pancreatitis evolution was similar to standard pancreatitis evolution. In a life threatening post ES hemobilia, not responding to standard medical treatment, angiography is the diagnostic exam of choice before embolization which is regarded as the best initial treatment of vascular lesions. We conclude that CT is the exam of choice in the initial diagnosis and follow up post ES complications.

Acute Disease↗
PubMed1996

Rectourethral fistula due to Crohn's disease.

Fistulas between the large bowel and the prostatic urethra, due to Crohn's disease, are very uncommon. Pneumaturia and an abnormal urethral discharge are the most common symptoms. Diagnosis is made by a voiding cystourethrogram or a retrograde urethrography. Treatment is usually difficult with a high percentage of recurrence. A well documented case is presented.

Adult↗
PubMed1996

[Localised primary lesion of the right pulmonary artery in Takayasu's disease].

Takayasu's disease involves the pulmonary vessels in over 50% of cases. However, primary lesions of the pulmonary arteries are very rare. The authors report the cases of a 34 year-old Caucasian woman presenting with clinical and radiological signs of acute pulmonary embolism, but in whom the pulmonary angiography showed stenotic and occlusive lesions of the right pulmonary artery. MRI provided an accurate diagnosis by showing typical thickening of the pulmonary arterial walls.

Acute Disease↗
PubMed1996

[An unusual case of cardiac insufficiency].

A 70 year old patient with a past history of a left ventricular cardiomyopathy with concentric hypertrophy presented with an exacerbation of cardiac failure; radiology revealed bilateral lung infiltrations, predominantly on the right and a restrictive ventilatory disorder. The broncho-alveolar lavage revealed a lymphocytosis with CD4 prominence. Microbiological examination was negative. With a worsening radiological picture despite increased anti-failure treatment a video-assisted surgical biopsy was performed. The histological examination revealed diffuse interstitial pulmonary amyloidosis. This observation underlined the value of looking for this rare cause of cardiac failure and pulmonary infiltration in a situation where the pulmonary images did not improve on diuretics.

Aged↗
PubMed1995

[Valve ring abscesses: apropos of 59 cases. A multicenter study].

The authors report the results of a multicenter study which recensed 59 cases (46 men, 13 women, average age 59.8 +/- 14 years) of valve ring abscesses defined by echocardiographic criteria alone (20 cases) or by echocardiographic and/or operative criteria (39 cases). The site of abscess was aortic (53 cases), mitral (5 cases) and tricuspid (1 case). The abscess complicated a prosthetic valve in 34 cases, occurred with a non-pathological valve in 11 cases or a pathological valve in 14 cases. Taking the 39 operated patients as a reference, the diagnostic sensitivity of transthoracic echocardiography was 25% and that of transoesophageal echocardiography: 88%. Bacterial vegetations were diagnosed with a sensitivity of 55% for transthoracic and 88% for transoesophageal echocardiography. The mediocre results of transthoracic echocardiography make transoesophageal echocardiography mandatory when there is a clinical suspicion of abscess: transoesophageal echocardiography should be systematic in prosthetic valve endocarditis and widely employed in native aortic valve endocarditis. The clinical outcome of these cases was: 39 cases were operated: global mortality of 23%, and 18 cases were treated medically, surgery having been declined for various reasons: old age (2 patients), operative risk (1 patient), patient refusal (4 patients), general condition considered to be too good to justify surgery (11 cases, including 6 sterilised abscesses diagnosed some time after the acute infectious phase). The outcome of these 18 patients, who form the biggest non-operated series of valve ring abscesses to date, was studied in detail: 4 died (18% mortality), 1 was operated secondarily for progressive valve dehiscence and 13 had a favourable outcome with an average follow-up period of 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Abscess↗
PubMed1995

Ambulatory chronotherapy with 5-fluorouracil, folinic acid, and carboplatin for advanced non-small cell lung cancer. A phase II feasibility trial.

Thirty-two patients with advanced non-small cell lung carcinoma (NSCLC) received a chronomodulated 5-day venous infusion of 5-fluorouracil (5 FU) (700 mg/m2/day), folinic acid (F) (300 mg/m2/day), and carboplatin (C) (40, 50, or 55 mg/m2/day), as first chemotherapy. Courses were repeated every 21 days (after a 16-day interval). In total, 158 courses (median: 4, range: 1 through 16; 81 and 58 courses at, respectively, a 40 and 50 to 55 mg/m2 daily dosage of C) were delivered using a multichannel programmable in-time pump (Intelliject, Aguettant) connected to a double lumen implanted venous side-port. The administration was allowed in fully ambulatory convenience. Overall tolerance was excellent. Grade 3 of 4 hematologic toxicity was encountered in 4.6% of courses for thrombopenia and in 7.0% of courses for neutropenia. Nausea or vomiting (grade 3 or 4) occurred in 7.8% of courses. Mucositis, diarrhea, alopecia, or skin grade 3 or 4 toxicity were observed in less than 3% of courses. Treatment delay was needed in only 7.8% of courses and dose reductions were needed in 4.6% of courses for 5 FU and in 6.5% of courses for C. This good tolerance allowed a sustained quality of life and prompted further trials aiming to define the place of this protocol in the multidisciplinary treatment approach of NSCLC.

Adult↗
PubMed1994

[Diagnosis and staging of colorectal cancers].

Early colorectal cancer produces no symptom, thus justifying efforts at detection in screening programs. Symptoms are usually secondary to obstruction, local invasion, perforation or bleeding. Any fecal bleeding must be investigated to rule out a colorectal cancer. The initial imaging study to identify a colorectal cancer is often colonoscopy, which is frequently supplemented with a double contrast barium enema. Once the presence of cancer is histologically proven, the preoperative evaluation includes detection of hepatic and extrahepatic spread, especially with ultrasound and CT scan. Endorectal ultrasonography has been shown to be a significant advance for staging rectal cancer. It provides the best staging in selecting patients for preservation of sphincter function and for adjuvant therapies. The most useful prognostic factors in tumors without distant metastases are the depth of tumor extension, the number of positive lymph nodes and the histologic grade. Preoperative CEA level, vascular invasion and ploidy are also important prognostic factors.

Colorectal Neoplasms↗
PubMed1994

Longitudinal changes in serum zinc concentration and distribution after acute myocardial infarction.

The authors studied the changes in serum zinc concentration and distribution during the 15 days following acute myocardial infarction in 21 patients. The method is based on ultrafiltration and electrothermal atomic absorption spectrometry. It is rapid and needs only 2.5 ml of serum. Serum and erythrocyte copper and zinc, serum zinc-binding ligands and serum enzyme activities were also determined. Serum zinc (P < 0.00001) and exchangeable zinc (mainly albumin-bound zinc, P = 0.01) declined within the first 3 days and then returned gradually to reference ranges. Exchangeable zinc was correlated with transthyretin (P = 0.00001) and total serum zinc (P < 0.00001). Exchangeable zinc accounted for virtually all of the differences in total serum zinc concentration after myocardial infarction. This result could be related to an increase of zinc uptake by tissues. Therefore, studies are needed to evaluate whether zinc supplementation in the early stages of acute myocardial infarction might improve prognosis.

Adult↗