ABSTRACT In diploid late-acting self-incompatible (LSI) species of Bignoniaceae, self-pollinated pistils show a marked delay in ovule penetration by pollen tubes, followed by delayed, but otherwise normal, initial stages of endosperm development and subsequent pistil abscission. Most polyploid species of Bignoniaceae are apomictic and set selfed fruits with viable polyembryonic seeds carrying adventitious embryos. Handroanthus serratifolius is a polyploid species with sporophytic apomictic individuals that produce polyembryonic seeds after either self- or cross-pollination, and other LSI individuals that produce exclusively monoembryionic seeds. Our aim was to determine whether self-sterility events in the latter are similar to those observed in other diploid LSI species of Bignoniaceae. No conspicuous differences in the progress of ovule penetration, fertilization and early stages of endosperm development were observed between selfed and crossed pistils, which contrasts with the marked delay observed in these events after self-pollination in diploid LSI species of the family. Adventitious embryo precursor cells (AEPs) were observed in some ovules, but they apparently do not develop into embryos. We believe that the AEPs in these plants represent a ‘potential’ for sporophytic apomixis, which would explain the similar behaviour of post-pollination events in selfed vs. crossed pistils despite their inability to set fruits after selfing.

Polyploidization is common among angiosperms and might induce typically allogamous plants to become autogamous (self-compatible, relying on sexual self-fertilization) or apomictic (achieving asexual reproduction through seeds). This work aimed to determine whether neopolyploidy leads to the breakdown of the self-incompatibility system in the hexaploid non-apomictic species Handroanthus serratifolius (Vahl) S. Grose, through analyses of its floral biology, pollination biology and breeding system. Although anthesis lasted for three days, increasing the overall floral display, receptivity decreased as of the second day. Centridini and Euglossini bees were the main pollinators, and low nectar availability (1.95 ± 1.91 µl/flower) might have obliged them to visit multiple flowers. We observed low reproductive efficacy. That might be explained by self-sterility and by the great number of flowers per individual, which could increase the frequency of geitonogamy. Ovule penetration by the pollen tubes in self-pollinated pistils with posterior abscission indicated late-acting self-incompatibility in H. serratifolius, as observed in other diploid Bignoniaceae species, although inbreeding depression cannot be excluded. The self-sterility found in the monoembryonic, hexaploid individuals studied here contrasts with the results for other neopolyploid Handroanthus and Anemopaegma species, which are often autogamous and apomictic. Our results suggest that neopolyploidy is not the main factor leading to self-fertility in Handroanthus.

A origem dos embriões supranumerários e a embriogenia de Tabebuia ochracea foram analisadas. Embriões supranumerários apomíticos têm origem adventícia a partir de células da hipóstase e do tegumento da região micropilar do óvulo. A embriogenia corresponde ao tipo Onagrado. Das 233 sementes dissecadas 81,37% apresentaram poliembrionia e foram encontrados até sete embriões em uma mesma semente. Aparentemente, embriões sexuais e adventícios podem se desenvolver juntos, numa mesma semente. Alguns dos embriões adventícios apresentam alterações morfoanatômicas graves que podem prejudicar seu desenvolvimento em plântulas.

The origin of the extranumerary embryos and the embryogeny of Tabebuia ochracea were analysed. Extranumerary apomictic embryos are of adventitious origin from hypostase cells and from the integument of ovule micropilar region. The embryogeny corresponds to Onagrad type. Among 233 dissected seeds, 81.37% presented polyembryony and up to seven embryos were detected in a single seed. Sexual and adventitious embryos can develop together in a single seed. Some of the adventitious embryos show severe morphoanatomical anomalies that can affect their development into seedlings.

Forty-nine AIDS patients, most of who were antiretroviral therapy (ARV) naïve, with active tuberculosis, were treated with Rifampin 600mg, Isoniazid 400mg and Pirazinamide 2g daily. They also received ARV, consisting of Efavirenz (600mg/day) plus 2 NRTIs. All patients were prospectively followed for at least 24 months. Baselines were: male/female ratio 2:1, mean age 34.7 ± 9.4 yrs; weight 51 ± 9.0 kg, viral load 5.6 ± 0.6 logs, CD4 cell count 101 ± 128 cells/ mm³. Follow up mean values of data logs of VL and CD4+ cell /mm³ counts were: VL 1.7 and CD4+ 265; VL 1.3 and CD4+ 251; VL 1.4 and CD4+ 326 at 6, 12 and 24 months, respectively. Weight gain changes were: 5 ± 9.9 ± 12 and 21 ± 16 kg respectively at 6, 12 and 24 months. A non-concomitant ARV regimen was introduced at least three weeks after TB treatment initiation. Severe adverse reactions included rash (two), toxic hepatitis (six), Immune Reconstitution Syndrome (seven), and four deaths. We conclude that Efavirenz at a daily dose of 600 mg is sufficient and safe to treat HIV/TB patients using a Rifampin containing regimen.

Diarrhea due to intestinal microbial infections is a frequent manifestation among HIV-infected patients. It has been postulated that HIV-infected patients may have special types of intestinal infections, and that immune activation from such parasites may affect the progression of HIV disease. To evaluate these associations, the frequency of infections was examined in HIV-infected patients in Bahia, Brazil. To determine the potential impact of the presence of intestinal parasitic infections on HIV disease progression, a retrospective study approach was used. The medical charts of 365 HIV-infected patients who had been treated at the AIDS Clinic of the Federal University of Bahia Hospital were reviewed, and the prevalence of parasites was compared with 5,243 HIV-negative patients who had attended the hospital during the same period of time. Among HIV-infected subjects, CD4 count, RNA plasma viral load (VL), and number of eosinophils were compared according to their stool examination results. The overall prevalence of each parasite was similar for HIV-positive and HIV-negative patients. However, the prevalence of S. stercoralis (p<10-7) and G. lamblia (p=0.005) was greater for HIV-infected subjects. The mean CD4 count and viral load of HIV patients in our clinic who had stool examinations was 350 cells ± 340 and 4.4 ± 1.4 log RNA viral load, respectively. In this patient group there was no clear association between the level of the absolute CD4 count or the viral load and a specific parasitic infection. The presence of an intestinal parasitic infection was not associated with faster progression of the HIV disease among HIV-infected patients.We conclude that strongyloidiasis and giardiasis are more frequent in HIV-infected patients in Bahia, Brazil. If this association is due to immune dysregulation, as has been proposed elsewhere, it must occur in patients after only minor shifts in CD4 count from normal levels, or as a result of immune dysfunction not represented by CD4 count. These infections do not appear to alter the progression of HIV disease.