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The role of dendritic Langerhans cells (LCs) in the immunopathogenesis of American cutaneous leishmaniasis (ACL) was reviewed in the light of more recent clinical and immunological features of ACL, caused by the principal human pathogenic leishmanial parasites found in Brazil: Leishmania (Viannia) braziliensis and L. (L.) amazonensis. The report shows a species-specific correlation between the LC density and the CD4+ and CD8+ T-cell profiles in the cellular infiltrate of skin lesions of ACL patients, providing the conclusion that LCs might be influencing the dichotomy of interaction between L. (V.)
Anti-Müllerian hormone (AMH), also known as Müllerian inhibiting substance (MIS), is expressed by granulosa cells in females of many mammalian species, and circulating AMH concentrations have been used to monitor granulosa-cell tumors (GCT) in women. The objective was to characterize expression of AMH in equine GCT, and in normal equine ovaries, based upon immunohistochemistry (IHC), using a polyclonal primary antibody directed against human AMH. Equine GCT (n=27) and normal equine ovaries (n=10) were examined by IHC. In addition, sera from four mares with GCT were characterized for AMH bioactivity, based upon suppression...
Preliminary screening of fungi and bacteria isolated from unmanaged mango trees in different ecologies of Ethiopia, yielded isolates antagonistic towards Colletotrichum gloeosporioides, the cause of mango anthracnose. Four isolates of bacteria, five yeasts and two filamentous fungi were evaluated in this study. Cell suspensions and culture filtrates of the isolates inhibited spore germination and hyphal growth of C. gloeosporioides in vitro. The isolates significantly reduced severity of anthracnose on artificially inoculated mango fruit. Brevundimonas diminuta isolate B-62-13, Stenotrophomonas maltophilia L-16-12, a member of Enterobacteriaceae L-19-13, Candida membranifaciens F-58-22, and the yeast isolate...
Uptake and depuration kinetics of Cd, Co, Cr, Mn, Ni and Zn were determined in the brown alga Lobophora variegata exposed to realistic concentrations of these metals, using highly sensitive radiotracer techniques. The experiments were designed to assess the possible influence of varying dissolved metal concentrations on the capacity of metal bioconcentration and retention in the alga. Results indicate that the alga takes up Cd, Co, Cr, Ni, and Zn in direct proportion to their ambient dissolved concentrations over the entire range of concentrations tested (three orders of magnitude). In contrast, Mn was taken up in proportion...
The Knudsen effusion mass spectrometric technique was used to study vapor species over praseodymium triiodide. The monomer, PrI3, and dimer, Pr2I6, molecules and the negative ions, PrI4− and Pr2I7−, were observed in saturated vapor in the temperature range from 856K to 1048K. The partial vapor pressures of neutral constituents were determined and the enthalpies of sublimation obtained using the second and the third laws of thermodynamics (ΔsH°(298.15K)=291±4kJmol−1 for PrI3, and ΔsH°(298.15K)=400±
In the environment, the sorption and the degradation of organic pollutants are of increasing interest. The investigation of the chemical structures provides a basis for the development of a suitable binding model approach and for the mechanistic understanding of the chemical fate processes. The aim of this study was the identification of different species of the antibiotic compound sulfadiazine (SDZ) using 1H and 13C NMR experiments and ab initio density functional theory (DFT) calculations. In the neutral, aprotic solvent dimethylsulfoxide-d6 (DMSO-d6), a new sulfadiazine structure containing an O–H–N hydrogen bond was identified....
Several approaches have been suggested and evaluated for reducing ammonia emissions from excreted animal manure: reducing nitrogen excretion through dietary manipulation, reducing volatile ammonia in the manure to stop ammonia loss, and segregating urine from faeces to reduce contact between urease and urine. When urine–faeces segregation is not an option, urease inhibitors can also be used to reduce or eliminate the hydrolysis of urea into ammonia. Methods for reducing the more volatile ammonia in manure include the reduction of pH, which shifts the equilibrium in favour of ammonium over ammonia; use of other chemical additives that bind ammonium-N; and...
Environmental enrichment is an important strategy to improve the welfare of laboratory animals. Running wheels might serve as enrichment devices for laboratory mice, since mice use them extensively when they are provided. However, competition among group-housed mice for such highly preferred enrichment devices could also lead to injurious aggression. We therefore assessed the effects of providing a running wheel-igloo enrichment on the social behaviour of group-housed male mice. CD-1 (ICR) mice (n=60, 20 per treatment) were housed in standard polycarbonate cages (five mice per cage) for 2 weeks (BASE), and then placed in either: (1)...
Bacteria that cause pneumonic plague can evade our first-line defences, making it difficult for the body to fight infection. In fact, a signature of the plague is the lack of an inflammatory response. Now, scientists have discovered a way to protect against death following infection with plague bacteria, by using molecules that can mimic the pathogens. According to research published in the July issue of Microbiology, these molecules make antibiotics more effective and can even be used to protect against other diseases.
The third edition of The Ciliated Protozoa continues the innovative approach of the previous two editions, thoroughly documenting the progress in our understanding of the evolutionary diversification of these widely distributed eukaryotic microorganisms. The Glossary is considerably revised and expanded, serving as an illustrated ‘subject index’ of more than 700 terms. An ...
As I noted previously, I'm presently on vacation. Unfortunately, I'm in areas with very sporadic web access, so I'm only posting when I can!
We spotted this sparrow's-egg lady's slipper on the trail to the mineral licks just north of Muncho Lake (in northern British Columbia). I'd been hoping to see this species on my trip, but wasn't really expecting to find it so soon (on the morning of the third day). We could only find a few individuals in the shady areas of some mixed forest.
Read more about this orchid via the USDA's "Meet the Ladies": Cypripedium passerinum. The Flora of North America also has its scientific account of this species.
Seminal products transferred during copulation can have substantial effects on females, including accelerated oviposition, decreased mating receptivity and shorter life span. This study addresses two sets of hypotheses about ingested seminal products: (1) whether they act as nutrition or have effects like those of seminal proteins and (2) whether they harm females (implying sexual conflict). We studied the ladybird beetle Adalia bipunctata, the females of which consume a spermatophore after mating. To examine the effect of spermatophore feeding on short-term reproduction, we combined a spermatophore treatment (allowing or preventing ingestion) with a diet manipulation. If spermatophores serve only...
The temperate comb-footed spider, Anelosimus studiosus, shows a social behaviour polymorphism: individuals may defend asocial nests against intrusion by conspecifics or cooperate with them in multifemale nests. A suite of behavioural traits, including response to predators and prey, degree of superfluous killing, exploratory behaviour and general level of activity, was examined in laboratory trials to: (1) establish the extent to which these traits are correlated with social phenotype and (2) explore the potential adaptive value of this trait suite to the respective asocial and social phenotypes. Populations from the two latitudes studied, 26° and 36°, showed similar suites...
Phylogeny of Chaetanthera (Asteraceae: Mutisieae) reveals both ancient and recent origins of the high elevation lineages.
Mol Phylogenet Evol. 2006 Dec;41(3):594-605
Authors: Hershkovitz MA, Arroyo MT, Bell C, Hinojosa LF
Penalized likelihood analysis of previously published chloroplast DNA (cpDNA) ndhF sequences suggests that the central-southern Andean genus Chaetanthera diverged ca. 16.5 million years (my) ago, well before the uplift of the Andes to their present heights. Penalized likelihood analysis based on new nuclear ribosomal DNA (rDNA) internal transcribed spacer (ITS) sequences indicates that the most relictual lineages occupy high elevation Andean habitats that did not exist until some 10my later. This result is contrary to the expectation that younger habitats should be occupied by phylogenetically younger lineages. The results are interpreted with respect to the development of aridity in lowland habitats during the Miocene and Pliocene, which presumably extinguished the lowland relatives of the high elevation taxa or, in effect, forced them upwards in search of adequate moisture. As the more northerly lineages were being displaced upward, others diversified in the mediterranean-type climate area of central Chile, giving rise to additional high elevation taxa again, at an early date, as well as lowland taxa. Some species of Chaetanthera from lowland central Chile appear as the phylogenetically youngest taxa, suggesting secondary adaptation to lowland aridity. At the same time, at least two high elevation species, Chaetanthera peruviana and Chaetanthera perpusilla, appear to have been derived recently from a lower elevation ancestor, while some middle to low elevation taxa seem to have evolved recently out of a high elevation complex. The results suggest that the younger high elevation habitats have served as both "cradle" and "museum" for Chaetanthera lineages.
PMID: 16854602 [PubMed - indexed for MEDLINE]
