Macroinvertebrate communities associated with duckweed (Lemnaceae) in two Eastern Cape rivers,South Africa

The functional feeding groups and diversity of macroinvertebrate communities associated with duckweed mats in the New Years River (two sites) and Bloukrans River (two sites), Eastern Cape province, South Africa, were assessed. Duckweed (Lemnaceae) is a ubiquitous family of floating macrophytes. A total of 41 macroinvertebrate families were collected monthly over a six-month period from February to July 2014. Duckweed biomass in both rivers was highly variable both temporally and spatially. The majority of identified macroinvertebrate taxa were predators and detritivores, with a small percentage of herbivores. An average of approximately 26% of the macroinvertebrate taxa found were from families that include species from more than one functional feeding group. Although overall measures of diversity and ecosystem health (Fisher’s α and Simpson’s index) remained constant over time in the New Years River, significant differences in macroinvertebrate community structure were seen between sites and months on both rivers, with dissimilarity being driven by a larger number of species in the New Years River. This high variability within macroinvertebrate assemblages probably reflects a combination of heterogeneous duckweed distribution, variation in physico-chemistry, opportunistic behaviours of macroinvertebrate predators and/or successional colonisation of duckweed mats.     

Flow cytometric analysis of whole blood lysis, three anticoagulants, and five cell preparations.

We studied the effects of anticoagulants and cell preparation methods on lymphocyte forward-angle scatter (FSC), autofluorescence, and immunofluorescent staining for CD45, CD14, and CD13. Blood samples collected in ethylenediaminetetracetic acid (EDTA), heparin, and acid citrate dextrose (ACD) were processed by using conventional Hypaque-Ficoll (HF) separation and four whole blood (WB) lysis techniques: Immuno-lyse, Q-Prep, FACS Lyse, and Gen Trak Lysis. Lymphocytes prepared by using three of the four whole blood methods gave FCS values comparable to those isolated by HF, while one method (FACS Lyse) gave consistently lower values. Autofluorescence values were comparable by all methods except Immuno-lyse, which showed consistently higher values in blood stored for 24 h with any anticoagulant. Immunofluorescent values for CD45-stained cells were quite consistent across all methods, and among the whole blood methods, FACS Lyse and Q-Prep uniformly gave the highest purity of CD45-positive cells in the lymphocyte light scatter gates. Additionally, propidium iodide (PI) analyses of CD45-stained whole blood, and analyzed without lysis, confirmed that ACD and heparin were superior to EDTA for maintaining viable leucocytes overnight. Future studies should focus on other commonly used reagents, a wide variety of abnormal samples, and cell viability.     

Genetic analysis of the two zebrafish patched homologues identifies novel roles for the hedgehog signaling pathway

Background  

Aberrant activation of the Hedgehog (Hh) signaling pathway in different organisms has shown the importance of this family of morphogens during development. Genetic screens in zebrafish have assigned specific roles for Hh in proliferation, differentiation and patterning, but mainly as a result of a loss of its activity. We attempted to fully activate the Hh pathway by removing both receptors for the Hh proteins, called Patched1 and 2, which are functioning as negative regulators in this pathway.     

A Bayesian approach for constructing genetic maps when markers are miscoded

The advent of molecular markers has created opportunities for a better understanding of quantitative inheritance and for developing novel strategies for genetic improvement of agricultural species, using information on quantitative trait loci (QTL). A QTL analysis relies on accurate genetic marker maps. At present, most statistical methods used for map construction ignore the fact that molecular data may be read with error. Often, however, there is ambiguity about some marker genotypes. A Bayesian MCMC approach for inferences about a genetic marker map when random miscoding of genotypes occurs is presented, and simulated and real data sets are analyzed. The results suggest that unless there is strong reason to believe that genotypes are ascertained without error, the proposed approach provides more reliable inference on the genetic map.     

Local administration of glucocorticoids decreases synovial citrullination in rheumatoid arthritis

Introduction

Protein citrullination is present in the rheumatoid synovium, presumably contributing to the perpetuation of chronic inflammation, in the presence of specific autoimmunity. As a result, the present study examined the possibility that effective antirheumatic treatment will decrease the level of synovial citrullination.

Methods

Synovial biopsies were obtained from 11 rheumatoid arthritis (RA) patients before and after 8 weeks of treatment with 20 mg methotrexate weekly, 15 RA patients before and 2 weeks after an intraarticular glucocorticoid injection, and eight healthy volunteers. Synovial inflammation was assessed with double-blind semiquantitative analysis of lining thickness, cell infiltration, and vascularity by using a 4-point scale. Expression of citrullinated proteins (CPs) with the monoclonal antibody F95 and peptidylarginine deiminase (PAD) 2 and 4 was assessed immunohistochemically with double-blind semiquantitative analysis. In vitro synovial fluid (SF), peripheral blood (PB), mononuclear cells (MCs), and synovial explants obtained from RA patients were incubated with dexamethasone and analyzed with immunohistochemistry for expression of CP as well as PAD2 and PAD4 enzymes.

Results

The presence of synovial CP was almost exclusive in RA compared with healthy synovium and correlated with the degree of local inflammation. Treatment with glucocorticoids but not methotrexate alters expression of synovial CP and PAD enzymes, in parallel with a decrease of synovial inflammation. Ex vivo and in vitro studies suggest also a direct effect of glucocorticoids on citrullination, as demonstrated by the decrease in the level of citrullination and PAD expression after incubation of SFMC and synovial explants with dexamethasone.

Conclusion

Synovial citrullination and PAD expression are dependent on local inflammation and targeted by glucocorticoids.     

Indomethacin and LY171883 modify porcine cardiopulmonary responses to leukotrienes

We evaluated the effects of leukotriene (LT) C4 (0.8, 1.6, 2.4 nmol/kg), LTD4 (0.2, 1.0, 2.0 nmol/kg), and LTE4 (4.6 nmol/kg) on the cardiopulmonary system in anesthetized pigs. LTC4 and LTD4 increased mean pulmonary arterial (Ppa), mean aortic (Pma), and peak tracheal (Pt) pressures and decreased cardiac index (Cl). After indomethacin (cyclooxygenase blocker) or indomethacin + LY171883 (LTD4/LTE4 receptor antagonist), the highest doses of sulfidopeptide LTs were repeated. Indomethacin attenuated the increased Ppa and Pt, but did not affect the decreased Cl or increased Pma; LY171883 blocked or greatly attenuated the residual responses. LY171883 (without indomethacin) also blocked or greatly attenuated the LT-induced increases in Ppa and Pma and the decrease in Cl. We conclude that sulfidopeptide LTs cause potent systemic and pulmonary vasoconstriction in the anesthetized pig. Moreover, approximately two-thirds of the pulmonary arterial hypertension is indirectly mediated (i.e., cyclooxygenase products), with the residual one-third possibly due to direct LT-receptor stimulation. On the other hand, systemic vasoconstriction and decreased Cl are independent of cyclooxygenase products, and thus are likely to be directly mediated by LTs. The data support an important interaction between LT receptors and release of cyclooxygenase products.     

Identification of biblical hyssop and origin of the traditional use of oregano-group herbs in the Mediterranean region

A comparative study of the traditional use of oregano-like herbs in the Mediterranean region provides convincing evidence that the hyssop of the Bible is the carvacrol chemotype of the plantMajorana syriaca. The ancient tradition of ritual use of this plant gave rise to two cultures of condiments: za’atar in the Middle East and oregano in Europe. The flavor of the original hyssop was the determining factor in this development and remained unchanged in oregano and za’atar throughout the centuries.