Multiple sclerosis retrovirus particles and recombinant envelope trigger an abnormal immune response in vitro, by inducing polyclonal Vbeta16 T-lymphocyte activation.

A retroviral element (MSRV) defining a family of genetically inherited endogenous retroviruses (HERV-W) has recently been characterized in cell cultures from patients with multiple sclerosis (MS). To address the possible relationship with MS, direct detection of circulating virion RNA was proposed but revealed technically difficult to perform in standardized conditions, in the face of multiple endogenous HERV-W copies. A parallel approach has evaluated MSRV potential pathogenicity in relation to characteristic features of multiple sclerosis, in particular, T-lymphocyte-mediated immunopathology. We report here that MSRV particles induce T-lymphocyte response with a bias in the Vbeta16 chain usage in surface receptor, whatever the HLA DR of the donor. A recombinant MSRV envelope-but not core-protein reproduced similar nonconventional activation. Molecular analysis of Vbeta CDR3 showed that Vbeta16 expansions are polyclonal. Our results thus provide evidence that MSRV envelope protein can trigger an abnormal immune response with similar characteristics to that of superantigens.

Sterol composition of itraconazole-resistant and itraconazole-susceptible isolates of Aspergillus fumigatus.

Sterol composition of four clinical isolates of Aspergillus fumigatus resistant to itraconazole was determined by gas chromatography--mass spectrometry and compared with that of four susceptible strains. For all strains, the major sterol was ergosterol. Sterol compositions were qualitatively and quantitatively similar for the resistant and susceptible strains. These results suggest that itraconazole resistance is not related, for the strains studied, to alterations in the ergosterol synthesis pathway.

Acquired itraconazole resistance in Aspergillus fumigatus.

The antifungal susceptibility profiles of four ASPERGILLUS: fumigatus isolates, recovered at different times from a patient treated with itraconazole for a pulmonary ASPERGILLUS: infection, were evaluated. Itraconazole MICs against two pre-treatment isolates were 0.5 mg/L, whilst two later isolates, recovered after at least 4 months of itraconazole therapy, had itraconazole MICs of >16 mg/L. In vivo susceptibilities to itraconazole and amphotericin B were tested in a murine model of disseminated aspergillosis. Treatment efficacy was evaluated by examining mortality rates and qualitative cultures of brain and kidneys. Itraconazole therapy significantly prolonged survival of mice infected with the initial isolates as compared with untreated controls. The third isolate was only partially susceptible to itraconazole in vivo, and the fourth isolate was highly resistant. The four isolates were typed by random amplified polymorphic DNA (RAPD) with four different primers. RAPD patterns obtained with each of them were identical, suggesting that the same strain was recovered over time and had acquired resistance to itraconazole.

[Liver transplantation with a graft taken from a heart transplant patient who was brain-dead]. / Transplantation hépatique avec un greffon prélevé chez un greffé cardiaque en état de mort cérébrale.

The shortage of organ donors has led to progressive softening of selection criteria for organ donation. We report on hepatic transplantation in a 55-year-old woman with primary biliary cirrhosis, whose donor was a 50-year-old heart transplant recipient who became brain stem dead, due to cerebral bleeding 8 months after transplantation. An orthotopic liver transplantation was performed. The postoperative course was uneventful and the recipient was alive and had normal liver function after a 42-month follow-up. Analysis of the literature included ethical consideration, potential hepatotoxic effects of immunosuppressive drugs and modification of the graft immunogenicity. It confirms that transplanted patients should not be a priori excluded from organ donation.

Amphotericin B resistance of Aspergillus terreus in a murine model of disseminated aspergillosis.

The in-vivo activity of amphotericin B and itraconazole against a clinical isolate of Aspergillus terreus was determined in a murine model of disseminated aspergillosis. MICs of amphotericin B and itraconazole for the strain, determined by an NCCLS-based technique, were 2 microg/ml and 1 microg/ml, respectively. Mice infected intravenously were treated with either itraconazole (50 or 100 mg/kg/day) or amphotericin B 4.5 mg/kg/day for 10 days. Treatment with both doses of itraconazole significantly prolonged the survival rates compared with those for untreated mice. In comparison, mortality rate and median survival time were identical for mice treated with amphotericin B and for mice given no therapy, indicating that the strain was highly resistant to amphotericin B in this model. Analysis of sterol composition showed that the major sterol was ergosterol. This suggests that amphotericin B resistance was not related to a modified sterol profile.

In-vitro susceptibility of Aspergillus spp. isolates to amphotericin B and itraconazole.

The MICs of amphotericin B and itraconazole for 230 isolates of Aspergillus spp., comprising 156 Aspergillus fumigatus, 20 Aspergillus terreus, 22 Aspergillus flavus, 17 Aspergillus nidulans and 15 Aspergillus niger, were determined by a broth microdilution method with RPMI 1640 medium. No isolate was detected with an MIC of amphotericin B >2 mg/L. Itraconazole MICs >16 mg/L were detected for four Aspergillus fumigatus and one Aspergillus nidulans isolates.

In-vivo itraconazole resistance of Aspergillus fumigatus in systemic murine aspergillosis. EBGA Network. European research group on Biotypes and Genotypes of Aspergillus fumigatus.

An animal model of disseminated aspergillosis was used to test the in-vivo activity of itraconazole against four isolates of Aspergillus fumigatus. Two reference isolates of A. fumigatus known to be resistant to itraconazole in vitro and in vivo were used as control isolates, and two new isolates were tested under the same conditions. For each isolate MICs for itraconazole and amphotericin B were determined by an NCCLS-based method. Mice infected intravenously were treated either with itraconazole 100 mg/ kg/day or amphotericin B 4.5 mg/kg/day for 10 days. Amphotericin B showed good in-vivo activity against all four isolates. For one strain, which had a low in-vitro MIC for itraconazole, in-vivo therapy with itraconazole prolonged the survival of mice and reduced fungal burdens in organs compared with untreated controls. In mice infected with a strain with a high MIC of >16 mg/L, itraconazole neither prolonged survival nor reduced fungal load in organs compared with controls. It is concluded that there is a relationship between MIC and treatment outcome in mice for A. fumigatus infection.

Comparison of a digestion-sedimentation technique with the Kato-Katz technique in the detection and quantification of S. mansoni eggs in light to moderate infections.

A comparison between a digestion-sedimentation technique (DST) and the Kato-Katz thick smear technique (KKT) in the detection and quantification of Schistosoma eggs in stool was carried out in 551 subjects. Specimen were collected one or two years after treatment with praziquantel from subjects living in a schistosomiasis endemic area of Mali. One hundred infections missed by the KKT were detected by the DST. Conversely, 35 infections missed by the DST were detected by the KKT (88% were light infections). More subjects were classified as lightly infected by the DST (p < 10(-3)) and more subjects were classified as moderately infected (101-400 epg) by the KKT (p = 0.02). The KKT produced higher counts than the DST among the youngest age group which was also the most infected. The principal advantage of the DST over the KKT was its better sensitivity to detect light infections resulting from a larger amount of stool processed.

Use of grafts procured from organ transplant recipients.

BACKGROUND: Massive intracerebral bleeding may cause brain stem death in transplant (Tx) recipients early or late postTx. We addressed the question as to whether Tx recipients may safely be used as organ donors. In particular, it is feared that exposure to immunosuppressive drugs may render those organs unsuitable for Tx. METHODS: We reviewed two case reports of liver grafts procured from Tx patients. In addition, we conducted a survey within United Kingdom Transplant Support Service Authority (UKTSSA) to delineate the UK experience in that area. RESULTS: Donor 1 was an 50-year-old heart Tx recipient who became brain stem dead due to cerebral bleeding 8 months postTx. His liver was used in an 55-year-old patient with PBC who is alive and well more than 22 months postTx. Donor 2 was a 22-year-old kidney Tx patient who developed cerebral bleeding 4 years postTx. His liver was used in a 65-year-old patient with PBC who is doing well more than 27 months postTx. During the study period of 1989-1995, 13 organs (9 kidneys, 3 hearts, 1 liver) were procured from 6 brain stem dead Tx patients (3 long, 2 heart, and 1 kidney Tx patients). Seven recipients are enjoying satisfactory graft function 1 to 7 years postTx; one kidney Tx recipient was relisted 4 years postTx due to chronic rejection; five functionning grafts were lost to patient death; primary nonfunction was seen in one heart Tx recipient. CONCLUSIONS: Tx patients can be successfully used as organ donors. In particular, chronic exposure to immunosuppression is not per se a contraindication to donation. Tx physicians confronted with the rare and tragic event of brain stem death in a Tx patient should not a priori exclude these patients from donation.

Use of spectrophotometric reading for in vitro antifungal susceptibility testing of Aspergillus spp.

A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72 h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.

Use of TCR ADV gene segments by the delta chain is independent of their position and of CD3 expression.

The CD3 signaling complex is required for cell surface expression and selection of both alphabeta and gammadelta TCR. In this study we analyzed TCRD transcripts in both wild-type and CD3-epsilon-deficient mice. We show that the repertoire of ADV segments used by the delta chain is unchanged in the latter. Not all ADV genes participate in making up the TCRD repertoire. However, their use does not depend on their distance from the other TCRD-forming segments. For example ADV12, situated at more than 870 kb from the DD region, is expressed as part of TCRD transcripts, whereas ADV8, members of which are proximal to the DD region, is not. These data suggest that the accessibility of ADV8 gene segments is differentially regulated during T cell development in the thymus. Taken together, our results suggest that TCRA and TCRD rearrangements are independently controlled, and that the absence of TCRA expression in CD3-epsilon-deficient mice is not due to a lack of accessibility of the ADV gene segments but rather to inaccessibility of the AJ gene region.

Differential chronology of TCRADV2 gene use by alpha and delta chains of the mouse TCR.

The genes coding for TCR alpha and delta chains share the same genetic locus (TCRA/D). The rules governing the utilization of a V gene with the alpha and delta chains have not been established. More specifically, it is not known whether the position of a gene within the locus influences its utilization in alpha and delta TCR. To elucidate these points, we mapped ADV2 genes in the TCRA/D locus of BALB/c mice and analyzed their utilization in TCR alpha and delta transcripts from thymi isolated from mice of different ages. Our results show that all ADV2 genes can be used by the two chains, but with strikingly different patterns. Moreover, ADV2 utilization by the alpha chain proceeds in successive concentric waves during development, suggesting a progressive regulation of gene accessibility and utilization. These results support independent control of TCRA and TCRD gene assembly.

Fluorogenic detection of viable Toxoplasma gondii.

In order to easily assess growth and destruction of Toxoplasma gondii in vitro, this report describes two double staining assays that both visualize live and dead organisms: acridine orange--ethidium bromide (AO-EB) and bisbenzimide (Hoechst 33258)--propidium iodide (B-PI). EB and PI were chosen for dead organisms staining while AO and B stain viable organisms. Thus, both double staining assays seem more informative than Giemsa staining or indirect immunofluorescence. They offer methods to study internal structure of the parasite as well as information on host-parasite relationships. Moreover, detection in culture are sensitive, easier, and less time consuming than previous methods. So, they should to be useful in strains behaviour analysis.

[Man-water contacts and urinary schistosomiasis in a Mauritanian village]. / Contacts homme-eau et schistosomiase urinaire dans un village mauritanien.

For the period September to December 1985, 1226 water contacts were recorded during 8 days of direct observation. Various activities were analysed in order to determine their responsibility in transmission. An index of exposure, allowing for duration of contact, body surface exposed and infectiousness of the water was calculated for each contact. Domestic contacts, primarily female, represented 62% of the observations but only 15% of total exposure. Conversely, contacts for recreational purposes mainly involved young boys and accounted for 14% of the observations and 70% of total exposure. Between 6 and 20 years of age the mean index of exposure by contact was higher in males than in females. Changing water contact behavior seems to be an unrealistic means of preventing transmission in the community studied. The most appropriate strategy of control would appear to be selective treatment of heavily infected individuals.

[Cutaneous South-American Leishmaniasis. Parasitological and serological diagnosis by indirect immunofluorescence and enzyme linked immunoassay (ELISA). 94 cases]. / Leishmaniose cutanée sud-americaine. Diagnostic parasitologique et sérologique par immunofluorescence indirecte (IFI) et enzyme linked immuno assay (ELISA). A propos de 94 cas.

A parasitological (direct test and culture) and serological (IIF and ELISA) survey was carried out in 94 soldiers infested by a cutaneous South American leishmaniasis during a training in the guyanese forest. 52 p.c of the parasitological tests were positive, direct test being much more sensitive than cultures. By this technique, Leishmania Viannia guyanensis was detected 8 times, and Leishmania Viannia braziliensis twice. I.I.F. was negative in all cases because the utilization of a non-homologous antigen in the promastigote form and of the condition of its preparation. ELISA test utilizing the same antigen in a soluble form was specific and its sensitivity was 52 p.c. This technique was positive in 52 p.c of the cases, corroborating some diagnosis for which parasitological test was negative. 66 p.c of the total cases were confirmed.

Schistosoma haematobium infection in Mauritania: two years of follow-up after a targeted chemotherapy--a life-table approach of the risk of reinfection.

Reinfection pattern among 6- to 20-year-old subjects was studied over 24 months in two Mauritanian villages of intense Schistosoma haematobium infection after a targeted chemotherapy with praziquantel involving the whole community. Subjects received treatment according to the presence of haematuria/proteinuria and this indirect screening technique was able to identify 98-100% of the heavily infected subjects (50 + eggs/10 ml). The two villages differed with respect to their characteristics, quality of follow-up and reinfection pattern. The post-treatment 6-month cumulative incidence during the two transmission periods following the chemotherapy, estimated from a subset of 116 subjects, was 18.0% and 20.5%. Reinfection rates were higher among males (Cox-Mantel: P = 0.0015), among children 6-10 years of age than older (P = 0.0078) and among subjects with more than 50 eggs/10 ml of urine before treatment than subjects with a lower egg output (P = 0.009). A Cox proportional hazard regression model was fitted and confirmed that gender, age and pretreatment level of infection were predictors of the rate of reinfection but that there was no interaction between these predictors.

[Anisoylated plasminogen streptokinase complex during the acute phase of myocardial infarction. Results of a multicenter double-blind study versus heparin]. / Le complexe streptokinase plasminogène acylé à la phase aiguë de l'infarctus du myocarde. Résultats d'une étude multicentrique en double aveugle versus héparine.

Two hundred and thirty-one patients admitted to hospital within 5 hours of the onset of symptoms of a primary myocardial infarction were randomised into 2 groups: one received thrombolytic therapy [anisoylated plasminogen streptokinase activator complex (APSAC): 30 IU in 5 minutes] and the other was given conventional heparin therapy (5,000 IU). Heparin was given to both groups 4 hours later (500 IU/kg/day); the APSAC (N = 119) was identical with respect to age, location of infarct, Killip classification, delay before randomisation (188 +/- 62 minutes). Coronary angiography and ventriculography were performed after 3.4 +/- 1.2 days, and angioscintigraphy and myocardial scintigraphy after 19 +/- 2.5 days to determine the size of the infarct and the quality of left ventricular function. Coronary patency was much higher in the APSAC group (77%) than the heparin group (37%) (p less than 0.001). The angiographic ejection fraction was significantly greater in the thrombolytic group than in the heparin group (53 +/- 13% vs 47 +/- 12%, p less than 0.002), the difference being statistically significant in the anterior and inferior infarct subgroups. At the third week, the difference remained significant in the anterior infarct subgroup: a 31 per cent reduction in necrosed myocardial mass was observed in the APSAC group (33% in anterior infarcts: p less than 0.05 and 16% in inferior infarcts: NS). The limitation of infarct size explained the smaller reduction in left ventricular systolic function (r = 0.73; p less than 0.01). The hospital and one year mortality was comparable in the two groups which was not surprising given the small number of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects on infarct size and left ventricular function of early intravenous injection of anistreplase in acute myocardial infarction. The APSIM Study Investigators.

A total of 231 patients suffering from a first acute myocardial infarction were randomly allocated within 4 hours following the onset of symptoms either to anistreplase or anisoylated plasminogen streptokinase activator complex (APSAC), 30 U over 5 minutes, or to conventional heparin therapy, 5000 IU in bolus injection. Heparin was reintroduced in both groups 4 h after initial therapy at a dosage of 500 IU/kg per day. A total of 112 patients received anistreplase and 119 received heparin within a mean period of 188 +/- 62 min following the onset of symptoms. Infarct size was estimated from single photon emission computerized tomography and expressed in percentage of the total myocardial volume. The patency rate of the infarct-related artery was 77% in the anistreplase group and 36% in the heparin group (p less than 0.001). Left ventricular ejection fraction determined from contrast angiography was significantly higher in the anistreplase group than in the heparin group (6 absolute percentage point difference). A significant 31% reduction in infarct size was found in the anistreplase group (33% for the anterior wall infarction subgroup [p less than 0.05] and 16% for the inferior wall infarction subgroup, NS). A close inverse relation was found between the values of left ventricular ejection fraction and infarct size (r = -.73, p less than 0.01). In conclusion, early infusion of anistreplase in acute myocardial infarction produced a high early patency rate, a significant limitation of infarct size, and a significant preservation of left ventricular systolic function, mainly in the anterior wall infarctions.

[Effect of thrombolytic agents on infarct size and left ventricle systolic function in myocardial infarction]. / Effet des thrombolytiques sur la taille de la nécrose et la fonction systolique ventriculaire gauche dans l'infarctus du myocarde.

The early intravenous administration of thrombolytic agents in the acute phase of myocardial infarction induces reperfusion of the artery responsible for the necrosis, thereby limiting the size of the infarct and preserving the left ventricular systolic function with consequent reduction of short- or long-term mortality. With the exception of urokinase, these effects have been demonstrated with all thrombolytic agents used so far, including streptokinase, plasminogen tissue activator and anistreplase. Owing to its special pharmacokinetic properties, the latest thrombolytic agent, formerly known as APSAC (anisoylated plasminogen streptokinase activator complex), provides a high arterial reperfusion rate with a low percentage of reocclusion. As a result, the mean size of the infarct is reduced by 31 per cent (36% in the case of anterior infarct), and the left ventricular systolic function is highly significantly preserved.