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R Guillemain

Publications and source records attributed to R Guillemain.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Electron beam scanner and thoracic transplantation].

To follow an heart transplantation, EBCT is more precise than ultrasonography and scintigraphy to calculate a stroke volume. In lung transplantation, it is important before surgery to know the value of right ventricule stroke volume in order to choice the surgical protocol. After lung transplantation SFE helps to follow the patient to look after complications, to drain a collection or to guide a biopsy. SFE contribution is discussed in rejection, infectious diseases, detection of immuno-induced carcinomas, in bronchiolitis obliterans and recurrence of the primitive disease.

Graft Rejection↗
PubMed1994

[Aspergillosis and renal, heart and lung transplantation].

The increase of organ transplantations during the last decades conjointly with the prescription of heavy immunosuppressive drugs, has led to an increased incidence of new invasive aspergillosis (IA). This study is a report of the Broussais Hospital experience from 1968 to 1993 on kidney, heart and heart and lungs transplantations. It concerns 21 IA cases. Incidence was 0.5% for kidney, 4.5% for heart and 18% for heart and lungs transplantations. The most important risk factors were the increase of immunosuppressive therapy (66% of the cases), neutropenia (19%), and renovation of the hospital wards (36%). Lung was the most frequent site of infection (95% of the cases), clinical symptoms were no significant. Diagnosis procedures were realised on biopsy (23%) and on bronchoalveolar lavage (66%). Usual amphotericin B treatment was disappointing: mortality rate of 77%, the liposomal preparation of the drug seemed to be more efficient: mortality rate of 50%. Itraconazole appeared to be used in succession with a careful adaptation of posology. Prophylactic amphotericin B in a local way (sprays and aerosols) led to a good efficiency jointly with the patient isolation during constructions in the hospital area.

Adolescent↗
PubMed1994

[Treatment of organ graft rejection by extracorporeal photochemotherapy].

Extracorporeal photochemotherapy is a recently developed immunomodulator treatment against heart and lung graft rejection. The recipient's mononuclear cells are screened and irradiated with UV-A in the presence of 8-methoxy-psoralene (8-MOP), then reinjected. We treated 4 patients who had begun to reject their heart and/or lung grafts, with this technique, using one session per week for 4 weeks, followed by one session every 2 weeks for 2 months, then one session per month. In all cases, extracorporeal photochemotherapy appeared to improve the clinical and biological status of these patients. Episodes of rejection which could not be reversed with immunosuppressor treatment alone were controlled.

Adolescent↗
PubMed1993

Elevated high density lipoprotein concentrations in heart transplant recipients are related to impaired plasma cholesteryl ester transfer and hepatic lipase activity.

Accelerated atherosclerosis is a major complication of heart transplantation, and is frequently associated with a dyslipoproteinemia characterized by a paradoxical increase in HDL-cholesterol concentration. To define this abnormality, the lipoprotein profiles of 25 heart transplant recipients (HTR) were analyzed and compared with those of 26 control subjects. HDL, as separated on the basis of density in 3 subfractions, were increased in concentration: HDL2: +51%, HDL3a: +29%, HDL3b: +32%. HDL2 and HDL3a displayed an enrichment in surface components, phospholipids, unesterified cholesterol and apo E, leading to an increased size compared with subfractions of similar density in the controls. The major steps of plasma HDL metabolism were investigated: cholesterol esterification (LCAT activity), cholesteryl ester transfer to apo B-containing lipoproteins (CETP) and the hepatic hydrolysis of HDL components (HL activity). We demonstrated a partial deficiency in CETP (-28%) and hepatic lipase (-36%) activities with normal LCAT activity. Correlations in total study population (HTR plus controls) evidenced negative associations between CETP activity and HDL3a concentrations and between HL activity and HDL2-cholesterol as a percent of total HDL-cholesterol. Therapeutic agents used in post transplantation treatment such as glucocorticoids and/or cyclosporine may be speculated thus to affect both CETP and HL activities and, by arresting the HDL cycle in a CE-saturated state, do decrease the efficiency of reverse cholesterol extraction at the site of the graft.

Apolipoproteins↗
PubMed1993

[Evaluation of a new rapid ELISA technique for detecting human cytomegalovirus antibodies (CMV). Applications in emergency blood transfusion and in organ transplantation].

Immunocubes can detect very low HCMV IgG levels with at least the same sensitivity as the reference technique: ELISA. Samples containing bacteria showed no particular interference on the test, and results for non-infected material were in agreement with those of ELISA. The rapid test did not give any false positive reactions even with samples from patients with very high antiherpes immunoglobulins levels. Samples from transplant patients at the beginning of seroconversion or diluted to IgG titers corresponding to ELISA cut-off values were always detected as positive by immunocubes. In view of the rapidity of the test, its high specificity, its ability to detect levels corresponding to extremely low IgG signals in ELISA, and the possibility of conserving objective proof of the test, we conclude that this rapid immunocube technique is of great interest for current serologic screening in an emergency context, especially for transfusion and organ transplantation.

Antibodies, Bacterial↗
PubMed1992

Primary gastrointestinal malignant lymphomas associated with Epstein-Barr virus after heart transplantation.

Gastrointestinal involvement has been reported in 12-21% of post-transplant lymphoproliferative disorders but is unusual in the setting of heart transplantation. We report four post-transplant lymphoproliferative disorders observed among the 174 heart transplant recipients of our series, all of which were primary malignant lymphomas of and confined to the digestive tract. The mean onset time from transplantation was 22 months. Small intestine lesions were present in all four patients, with gastric involvement in one. Histologically, the tumour was monomorphic of immunoblastic type in one case and polymorphic in the three other cases. Analysis of cytoplasmic immunoglobulins demonstrated the presence of a major monoclonal subset in all patients. Epstein-Barr virus genome was found in numerous tumour cells by in situ hybridization. The exclusive localization to the digestive tract and the lymphoepithelial lesions observed in two cases suggest that these lymphoproliferations might originate from mucosa-associated lymphoid tissue.

Adult↗
PubMed1991

Monoclonal and oligoclonal gammopathies in heart-transplant recipients.

Immunoglobulin abnormalities in serum from 76 heart-transplant recipients were examined by cellulose acetate and agarose gel electrophoresis. Monoclonal components were typed by immunofixation. IgG, IgA, and IgM and total kappa and lambda light chains were quantified by immunonephelometry. We confirm that both monoclonal and oligoclonal immunoglobulin banding are common in serum from these patients. Of the 149 serum samples examined, 21 (15%) had one monoclonal component and 53 (35%) had two or more. These monoclonal immunoglobulins were generally present at a low concentration and were transient. The class of immunoglobulins most commonly involved was IgG (about sevenfold more numerous than IgM); monoclonal IgA components and free light chains were not detected. The nephelometric kappa/lambda and heavy chain/light chain ratios were poor indicators of these abnormalities. Immunoglobulin abnormalities were not correlated with the sex and age of recipients, the pre-existing cardiopathy, the time since transplantation, or plasma concentrations of cyclosporine, but did correlate with plasma immunoglobulin concentration, biopsy findings, and viral infections, especially cytomegalovirus (CMV). A monoclonal IgG purified from a patient with a high titer of anti-CMV antibodies did not react with CMV antigens. The origin of these immunoglobulin abnormalities is unclear. Our data suggest that the presence of monoclonal or oligoclonal banding in heart-transplant recipients is of limited prognostic significance.

Adult↗
PubMed1990

Serum lipid abnormalities in heart transplant recipients: predominance of HDL2-like particles in the HDL pattern.

Accelerated coronary atherosclerosis is a major risk limiting long-term survival after heart transplantation and is commonly associated with dyslipoproteinemia even in subjects who were not dyslipoproteinemic before intervention. The purpose of this study was to analyse the abnormalities in the lipid profiles of 2 different groups of heart-transplanted males: 18 subjects with underlying ischemic heart disease (IHD) and 19 subjects with non-obstructive cardiomyopathy of unknown aetiology (CM). Both groups were compared to 33 healthy males. All patients were under immunosuppressive therapy including prednisone, cyclosporin A and azathioprine. A moderate hyperlipidemia was found in all transplant recipients, associated with high HDL-cholesterol concentrations in the CM group (1.80 +/- 0.37 vs. 1.29 +/- 0.23 mmol/l) and normal HDL-cholesterol levels in the IHD group (1.40 +/- 0.23 mmol/l). HDL subfractionation showed a marked increase in HDL2-cholesterol (CM: 1.12 +/- 0.32; IHD: 0.69 +/- 0.28; control: 0.40 +/- 0.17 mmol/l) while HDL3-cholesterol was significantly lower than in the control group. Analysis of HDL particle sizes showed in all transplant subjects an increase of an intermediate size particle HDL2a (diameter 9.0 +/- 0.10 nm) which is a minor form in control subjects. In the CM group, both the common HDL2b (10.2 +/- 0.13 nm) and HDL2a were abundant in 13 of 17 patients. The pattern was more heterogeneous in the IHD group but witnessed to a high frequency of HDL2a particles either alone (5/14) or associated with larger HDL2b (4/14) or with small HDL3 (4/14).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiomyopathies↗
PubMed1990

Effect of systemic hypertension on renal function and left ventricular hypertrophy in heart transplant recipients.

To evaluate the incidence, risk factors and effects of systemic hypertension on renal function and left ventricular hypertrophy after cardiac transplantation, 85 transplant recipients on triple drug, low dosage, immunosuppressive therapy were studied. After a mean follow-up period of 12.5 +/- 8.7 months, a high incidence of hypertension was observed in 57 (67%) of the patients, and 42 (71%) of the 57 had developed new hypertension. None of the pretransplant and posttransplant cardiovascular risk factors were significantly associated with posttransplant hypertension. Faster deterioration of renal function, as assessed by intraindividual variations of serum creatinine values, was demonstrated in hypertensive patients and appeared as an early indicator of cyclosporine nephrotoxicity in patients at risk for hypertension. Serial echocardiographic evaluations demonstrated an early increase in left ventricular mass and fractional shortening in both hypertensive and normotensive heart transplant recipients. Fractional shortening further diminished significantly in normotensive patients but remained elevated in hypertensive patients, demonstrating sustained enhanced contractility in this group. Further studies will help to determine the exact relation between cyclosporine dosages and hypertension and their respective roles in the development of renal insufficiency and left ventricular hypertrophy after cardiac transplantation.

Adult↗
PubMed1990

Interaction between roxithromycin and cyclosporin in heart transplant patients.

Cyclosporin is an immunosuppressive agent commonly used in transplant patients. It is actively metabolised by the cytochrome P450 system and interactions with drugs metabolised by the same system are predictable. This is particularly relevant since cyclosporin has a low therapeutic index and its renal toxicity is concentration-related. Roxithromycin, a new, well-tolerated macrolide with a weak interactive profile, uses the same isoenzyme of the P450 system as cyclosporin. To evaluate its interaction potential in clinical practice, 8 heart transplant recipients treated with cyclosporin for at least 1 month received roxithromycin for 11 days (150 mg twice daily). Bi-weekly controls of plasma cyclosporin concentrations and creatinine levels were carried out before, during and after roxithromycin treatment. A slight nonsignificant rise in cyclosporin concentrations was observed, but creatinine levels remained stable during roxithromycin treatment. Values of cyclosporin concentrations diminished after withdrawal of roxithromycin. Cyclosporin dosage adjustment was not necessary. There was a minor pharmacokinetic interaction, which can be considered safe for the usual therapeutic dosage of roxithromycin used.

Adult↗
PubMed1990

[Mid-term echographic evaluation of systolic function after cardiac transplantation].

The aim of this study was to analyse variations in left ventricular mass (LVM) and systolic function after cardiac transplantation and to evaluate eventual changes induced by the onset of systemic hypertension (HT). In a retrospective study, we selected the echocardiographic examinations of 42 patients performed at the end of the first month (M1), sixth month (M6), and at the end of follow-up (ME) after cardiac transplantation. The patients were divided into two groups (NT: n = 14; HT: n = 28) depending on whether hypertension occurred during follow-up. The average duration of follow-up was 12.8 +/- 6 months; this was comparable in the two groups. Mild left ventricular hypertrophy was observed from the first postoperative examination: M1 = 193 +/- 50 g; M6 = 199 +/- 62 g; ME = 197 +/- 45 g (NS). The hypertrophy was constant with time and related to wall thickening; it was associated with an increased left ventricular fractional shortening (FS) which decreased with time especially in the NT group (average/42 patients: M1 = 0.38 +/- 0.09; M6 = 0.34 +/- 0.08; ME = 0.35 +/- 0.05; p = 0.03 between M1 and ME). The influence of hypertension on the development of LVH and wall thickening was negligible. The role of transplant rejection should be considered: the repetition of episodes of rejection was less marked than the histological severity of rejection. The role of other factors (ischaemia, persistent haemodynamic abnormalities) is a matter of discussion.

Adult↗
PubMed1990

[Effect of hypertension on the renal and cardiac functions of patients with heart transplantation].

To evaluate the incidence, risk factors and effects of systemic hypertension on renal function and left ventricular hypertrophy after heart transplantation, 85 recipients under triple drug low low dosage immunosuppressive therapy were studied. After a mean follow-up of 12.5 +/- 8.7 months, high incidence of hypertension was observed in 67% of the patient and 71% had developed de novo hypertension. None of the pre-transplant nor post-transplant cardiovascular risk factors were significantly associated with post-transplant hypertension. Faster deterioration of renal function, as assessed by intraindividual variations of serum creatinine values, was demonstrated in hypertensive patients and appeared as an early indicator of cyclosporine nephrotoxicity in patients at risk for hypertension. [table: see text] Serial (early, intermediate, late) echocardiographic evaluations demonstrated early increase in left ventricular mass and in fractional shortening in both hypertensive and normotensive heart transplant recipients with sustained enhanced contractility in hypertensive patients. [table: see text] Further studies will help to determine the exact relationship between cyclosporine dosages and hypertension, and their respective roles in the development of renal insufficiency and left ventricular hypertrophy after heart transplantation.

Adult↗