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Biomedical subjects

E Petersen

Publications and source records attributed to E Petersen.

171 records · Page 10Linked to original sources

Age-dependent occurrence of protective anti-Plasmodium falciparum sporozoite antibodies in a holoendemic area of Liberia.

Antibodies to Plasmodium falciparum sporozoites were detected in children aged 6 months to 9 years, and in adults, in a holendemic village near Yekepa, Liberia, by enzyme linked immunosorbent assay (ELISA) using the recombinant circumsporozoite protein R32tet32 or by inhibition of sporozoite invasion (ISI) of hepatoma cells. Both assays were significantly correlated with each other and showed that anti-sporozoite antibodies increase with age. ISI was more sensitive than ELISA and demonstrated significantly increased anti-sporozoite antibodies at age 5-6 years, when young children show partial clinical resistance to malaria. These results suggest that anti-sporozoite antibodies, as measured by ISI, may contribute to protection against malaria.

Adult↗

A longitudinal study of antibodies to the Plasmodium falciparum antigen Pf155/RESA and immunity to malaria infection in adult Liberians.

118 adult Liberians from 2 villages were studied prospectively for one year with monthly blood examinations for malaria parasites. The crude parasite rate was 41.5% and the crude gametocyte rate was 6.1%. The inoculation rate varied between 0.075 in the dry season and almost 0.4 in the rainy season, which is in accordance with other data from holoendemic areas. 47.5% (56) had a titre to the Pf155/RESA antigen less than or equal to 1/50 ('low responders') and 52.5% (62) had a titre of greater than or equal to 1/250 ('high responders'). The response was not age-dependent in this adult population, which may suggest that genetic factors are determining whether the individual become a high or low responder. Antibodies against the Pf155/RESA antigen were measured in 2 surveys 8 months apart, and the mean antibody response to Pf155/RESA and its EENV sequence was constant without seasonal variation. Pf155/RESA high responders had lower parasite densities during all 3 seasons surveyed, and Pf155/RESA high responders, with high antibody reactivity against the (EENV)6 sequence from the 3' repeat region of Pf155/RESA, had significantly lower parasite densities in the rainy season of 1987. The data suggest that high titres of antibodies to the Pf155/RESA antigen, and especially to its EENV sequence, might play a role in protective immunity in adults.

Adult↗

Hyperpigmented dermal macules in children following the administration of Maloprim for malaria chemoprophylaxis.

The occurrence of an unexpected side effect following the use of Maloprim (pyrimethamine/dapsone) for malaria chemosuppression in 3-59 months old children in Sierra Leone is reported. As part of a trial of chemoprophylaxis and insecticide-impregnated bed nets, 2000 children received either Maloprim or placebo; 4% of children who received Maloprim fortnightly for more than 3 months developed hyperpigmented macules, whereas none of the children who received placebo did so. Histopathological examination of full thickness skin biopsies showed macrophages containing melanin in the dermal layer. Clustering of cases was noted among siblings, suggesting the possible involvement of genetic factors in the pathogenesis of these skin reactions. One child was accidentally re-exposed to Maloprim after the drug had been withdrawn and he developed a severe reaction. No other serious side effect was noted. Hyperpigmented lesions similar to those reported in this study have been described previously in patients with leprosy treated with dapsone, and the dapsone component of Maloprim is the likely cause of the skin reactions seen in children given this drug for malaria chemoprophylaxis.

Anti-Infective Agents↗

Ganciclovir treatment of serious cytomegalovirus infection in heart and heart-lung transplant recipients.

Experience with ganciclovir treatment of life- or sight-threatening cytomegalovirus (CMV) infections in 22 heart and heart-lung transplant recipients at six medical centers was reviewed. All six heart-lung recipients and six of 16 heart recipients had CMV pneumonitis; five heart recipients had CMV gastrointestinal disease, three had retinitis, and two had infections in more than one organ system. Of the 18 patients (82%) surviving initial ganciclovir therapy, 16 improved, one stabilized, and one showed no change in clinical status. All cultures positive for CMV before treatment became negative during therapy. Six patients (33% of survivors) had recurrent episodes and received additional therapy. Four patients (18%) died during initial therapy; death was believed to be related to CMV infection in only two cases and to ganciclovir treatment in no case. Adverse reactions possibly attributable to ganciclovir included neutropenia (four patients), impaired renal function (one), thrombocytopenia (one), decreased blood pressure (one), and seizure (one). Ganciclovir appears to be well tolerated and to alter favorably the outcome of serious CMV infection in this patient population.

Acyclovir↗

Reported side effects to chloroquine, chloroquine plus proguanil, and mefloquine as chemoprophylaxis against malaria in Danish travelers.

BACKGROUND: The aim of the study was to provide data on the relative frequency of reported symptoms in travelers using chloroquine, chloroquine plus proguanil, and mefloquine. METHOD: The study was an open, nonrandomized study recording self-reported events in travelers recruited consecutively from two travel clinics in Copenhagen, Denmark. The main outcome measures were the relative proportion of travelers reporting particular symptoms in the three prophylaxis groups, compliance, hospitalization and premature termination of the travel. RESULTS: From May 1996 to April 1998 5, 446 travelers were included and 4,158 questionnaires (76.3%) returned. Compliance was significantly better in mefloquine users with 83.3% of short term travelers compared to 76.3% in chloroquine plus proguanil users. Also, 84.8%, 59.3% and 69.5% using chloroquine, chloroquine plus proguanil, and mefloquine respectively reported no symptoms and 0.6%, 1.1% and 2.8% reported "unacceptable" symptoms. Compared to chloroquine, mefloquine users had a significantly higher risk of reporting depression, RR 5.06 (95% CI 2.71 - 9.45), "strange thoughts," RR 6.36 (95% CI 2.52 - 16.05) and altered spatial perception, RR 3.00 (95% CI 1.41 - 6.41). CONCLUSION: Overall mefloquine is tolerated at least as well as chloroquine plus proguanil and shows better compliance, however, symptoms related to the central nervous system are more prevalent in mefloquine users and when symptoms develop, they are perceived as more severe.

Antimalarials↗

Neospora caninum infection and repeated abortions in humans.

To determine whether Neospora caninum, a parasite known to cause repeated abortions and stillbirths in cattle, also causes repeated abortions in humans, we retrospectively examined serum samples of 76 women with a history of abortions for evidence of N. caninum infection. No antibodies to the parasite were detected by enzyme-linked immunosorbent assay, immunofluorescence assay, or Western blot.

Abortion, Habitual↗