Human intestinal parasites in Subsaharan Africa. I. Eastern Boè and Canhabaque Island (Guinea-Bissau)

A coprological survey was carried out in 1982-1983 in East Boè and in Canhabaque Island, (Bijagòs Islands), where 289 and 288 specimens of stools, respectively, have been collected. The samples were taken from apparently healthy subjects, of both sexes and of different age groups. The tests were made according to the modified Ritchie technique. The following results were obtained: A) East Boè: 1) Protozoa: E. coli 68.9%, E. nana 24.6%, G. intestinalis 8.7%, I. buetschlii 5.9%, E. histolytica 1.7%, E. hartmanni 0.7%, T. intestinalis 0.7%. b) Helminths: Ancylostomatidae 69.2%, T. trichiura 38.4%, S. stercoralis 6.2%, Taenia sp. 1.7%, H. nana 0.7%, S. haematobium 0.7%, S. mansoni 0.7%, S. fuelleborni 0.7%. B) Canhabaque: a) Protozoa: E. coli 85.1%, I. buetschlii 14.9%, E. nana 12.5%, G. intestinalis 8.3%, C. mesnili 7.3%, E. hartmanni 1.4%, E. histolytica 1.0%, T. intestinalis 0.4%. b) Helminths: Ancylostomatidae 87.9%, T. trichiura 9.4%, S. stercoralis 7.9%, S. fuelleborni 2.8%, Trichostrongylus sp. 1.4%, A. lumbricoides 0.7%, H. nana 0.4%. Eggs of Capillaria sp. probably pseudoparasites, were found in 8.7% of samples. The high prevalence of Ancylostomatidae infections appears to be related to the heavy fecal pollution all over the examined territory. The utilization of antihelminthic drug of popular medicine, which has a specific action on A. lumbricoides, could explain the lack and the low prevalence, respectively, of A. lumbricoides infections in both examined areas. In the past, other authors emphasized the low prevalence of this parasite for other Guinea Bissau regions which have a different geomorfological constitution. The cases of S. fuelleborni and H. nana are the first reported for Guinea Bissau.     

An adenovirus mRNA which encodes a 14,700-Mr protein that maps to the last open reading frame of region E3 is expressed during infection.

The E3 regions of adenovirus types 2 and 5, respectively, are known to synthesize proteins of 19,000 Mr (19K) and 11.6K, but information regarding the identity and characterization of other potential E3 proteins encoded by the six remaining open reading frames (ORFs) is lacking. In this study, we show that the last ORF of region E3, which encodes a 14.7K protein, is expressed in adenovirus-infected cells. This information was largely derived from analysis of an E3 deletion mutant (H2dl801) in which an extensive deletion (1,939 base pairs) was found to eliminate all ORFs except for two proteins of 12.5K and 14.7K. The 14.7K protein was translated from RNA isolated from H2dl801-infected cells that had been hybridization selected to E3 DNA; hybridization-selected RNA from wild-type adenovirus type 5-infected cells translated both the 19K and the 14.7K proteins. Moreover, an antiserum directed against a bacterial 14.7K fusion protein (A. E. Tollefson and W. S. M. Wold, J. Virol. 62:33-39, 1988) immunoprecipitated the 14.7K translation product synthesized by wild-type and mutant H2dl801 adenovirus mRNAs.     

Thaimycins,new anthelmintic and antiprotozoal antibiotics produced by Streptomyces michiganensis var. amylolyticus var. nova

Summary A new microorganism, isolated in our laboratories and identified as Streptomyces michiganensis var. amylolyticus var. nova is described.Thaimycins can be obtained by submerged fermentation of this microorganism on a suitable culture medium.Three new related compounds, thaimycins A, B and C have been obtained and characterized by their physical and chemical properties.Data on the antiprotozoal and anthelmintic activities in vitro as well as in vivo are reported.     

N-Acetyl-aspartylglutamate (NAAG) in human cerebrospinal fluid: Determination by high performance liquid chromatography,and influence of biological variables

Summary NAAG is one of the neuropeptides found in highest concentrations in the CNS. The presence of micromolar concentrations of NAAG in human CSF was demonstrated by using two different and complementary analytical approaches: 1) isocratic separation of endogenous NAAG by reverse-phase high performance liquid chromatography (HPLC) with dual wavelength detection and 2) derivatization of endogenous NAAG with acidic methanol and subsequent HPLC analysis of the derivative NAAG-trimethyl ester. The NAAG concentration was between 0.44µmol/l and 7.16µmol/l (mean of 2.19 ± 1.53µmol/l) in CSF samples from forty neuropsychiatric patients. Endogenous NAAG or [³H]NAAG added to CSF samples were not significantly degraded when the CSF was incubated at 37°C during one hour, suggesting that the peptide is a highly stable metabolite in the subarachnoid space. In addition, evidence is provided that NAAG does not present a concentration gradient along the lower subarachnoid space.     

Role of the tubulin-microtubule system in lymphocyte activation

The role of the tubulin-microtubule system was examined in human peripheral blood leukocytes after activation with phytohemagglutinin (PHA). Soluble tubulin and microtubules were measured with a [(3)H]colchicine-binding assay. It was found that the tubulin content of PHA-activated lymphocytes was consistently increased relative to total protein content after 36 h of culture. There was no increase in the proportion of total tubulin synthesis which was present as microtubules at 36 h. Nevertheless, as a result of increased tubulin synthesis, there was a two-to three-fold increase in total microtubular mass. Colchicine, which disrupts microtubles, was used to assess the role of microtubule assembly in the sequence of events which follow lymphocyte activation, namely lymphokine release, protein synthesis, RNA synthesis, and DNA synthesis. Colchicine consistently inhibited DNA synthesis but did not inhibit release of the lymphokine, osteoclast activating factor (OAF). Protein and RNA syntheses were inhibited much less than DNA synthesis. The fact that some effects of PHA on lymphocytes appear to require intact microtubules and at least one does not suggest that the microtubule dependent step in PHA-stimulated lymphocyte activation occurs at a stage after propagation of the signal from the membrane to the cell interior.