Zidovudine plus interferon-[alpha] versus zidovudine alone in HIV-infected symptomatic or asymptomatic persons with CD4+ cell counts > 150x106/l: results of the Zidon trial

Objective: To evaluate the efficacy and safety of zidovudine (ZDV) and lymphoblastoid interferon (IFN)-[alpha] combination therapy compared with ZDV monotherapy in HIV-infected subjects with CD4+ cell counts between 150 and 500x106/1. Design: Open, randomized controlled trial with subjects stratified by the Centers for Disease Control and Prevention (CDC) 1986 classification of HIV disease (group 11/111 or IV). The study was amended to a sequential design in February 1992 to allow interim analyses to be conducted. Setting: Outpatient clinics in 45 hospitals in Europe, Australia and Canada. Participants: A total of 402 previously untreated subjects with symptomatic HIV infection (CDC group IV) and CD4+ count 150-500xT06/1 or asymptomatic HIV infection (CDC group 11/111) with CD4+ count 150-350 x 106/l. Interventions: ZDV 250 mg twice daily with or without 3 MU subcutaneous injections of lymphoblastoid IFN-[alpha] three times per week. Main outcome measures: Time to development of a study endpoint defined as: progression from CDC group 11/111 to group IV, group IV non-AIDS to AIDS, or group IV AIDS to a second AIDS-defining condition; also CD4+ count to < 50x 106/1 on two occasions at least 1 month apart or HIV-related death irrespective of CDC group on entry. Results: There was no reduction in the rate of disease progression for patients receiving ZDV plus IFN-[alpha] compared with patients receiving ZDV alone. No major differences between the groups were seen for CD4+ counts or percentages, or p24 antigenaemia. In a subset of 70 patients, a similar proportion from both dose groups showed evidence of ZDV resistance after 48 weeks of treatment. More adverse experiences were seen in the ZDV/IFN-a group. Conclusions: Combination therapy with low dose lymphoblastoid IFN-[alpha] and ZDV revealed no clinical benefit compared with ZDV monotherapy

Marine influence in the Barreiras Formation, State of Alagoas, northeastern Brazil

Tidal processes were important for deposition of the Barreiras Formation located in northern Brazil, while correlatable deposits in northeastern Brazil have been traditionally related to continental environments. Facies analysis in southern Alagoas revealed that the Barreiras Formation consists of cross-stratified conglomerates and sandstones (facies Sx and Cgx), compound cross-stratified sandstones (facies Cx), and heterolithic beddings (facies H). A significant portion of these deposits occurs within channel morphologies displaying fining and thinning upward successions. An abundance of sedimentary features is comparable to those from the northern Brazilian counterpart. These include: tidal bundles; herringbone cross-stratification; heterolithic beddings with sandstone and mudstone beds in sharp contacts; and ichnofossils mostly consisting of Ophiomorpha nodosa, Skolithos and Planolites. Altogether, these features point to a marginal marine depositional setting dominated by tidal processes, which are related to an estuarine system, an interpretation also provided for the Barreiras Formation in northern Brazil. The widespread occurrence of deposits with unambiguous evidence of tidal processes in the Barreiras Formation of northern Brazil, and now in the State of Alagoas, leads to argue that the early/middle Miocene worldwide marine transgression might have left a much more widespread sedimentary record along the Brazilian coast than currently regarded.<br>Processos de maré foram importantes na deposição da Formação Barreiras localizada no norte do Brasil, enquanto depósitos correlatos do nordeste brasileiro têm sido tradicionalmente relacionados a ambientes continentais. Análise de fácies no sul de Alagoas revelou que a Formação Barreiras consiste em conglomerados e arenitos com estratificações cruzadas (facies Sx e Cgx), arenitos com estratificação cruzada composta (facies Cx), e acamamentos heterolíticos (facies H). Uma porção significativa desses depósitos ocorre inserida em morfologias de canal, internamente contendo sucessões de granocrescência e adelgaçamento ascendentes. A abundância de feições sedi-mentares é comparável àquelas documentadas em depósitos correlatos do norte do Brasil. Estas incluem: bandamentos de maré; estratificações cruzadas espinha-de-peixe; acamamen-tos heterolíticos contendo camadas de arenitos e argilitos em contato brusco; e icnofósseis consistindo principalmente em Ophiomorpha nodosa, Skolithos e Planolites. Estas feições apontam para ambiente deposicional marinho marginal dominado por processos de maré, possivelmente relacionado a sistema estuarino. Esta interpretação é similar à atribuída para a Formação Barreiras no norte do Brasil. A ampla ocorrência de depósitos contendo evidência inequívoca de processos de maré na Formação Barreiras no norte do Brasil, e agora também no Estado de Alagoas, leva a propor que o período de transgressão marinha registrada globalmente no eo/meso Mioceno pode ter deixado um registro sedimentar muito mais amplo ao longo da costa brasileira do que até então considerado