Acceptor specificity of the human leukocyte alpha3 fucosyltransferase: role of FucT-VII in the generation of selectin ligands

The alpha3 fucosyltransferase, FucT-VII, is one of the key glycosyltransferases involved in the biosynthesis of the sialyl Lewis X (sLex) antigen on human leukocytes. The sialyl Lewis X antigen (NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential component of the recruitment of leukocytes to sites of inflammation, mediating the primary interaction between circulating leukocytes and activated endothelium. In order to characterize the enzymatic properties of the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been expressed in Trichoplusia ni insect cells. The enzyme is capable of synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from 3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors demonstrate that FucT-VII is able to synthesize both di-fucosylated and tri-fucosylated structures from mono- fucosylated precursors, but preferentially fucosylates the distal GlcNAc within a polylactosamine chain. Furthermore, the rate of fucosylation of the internal GlcNAc residues is reduced once fucose has been added to the distal GlcNAc. These results indicate that FucT-VII is capable of generating complex selectin ligands, in vitro , however the order of fucose addition to the lactosamine chain affects the rate of selectin ligand synthesis.      

The effect of salts on the kinetics of iron release from N-terminal and C-terminal monoferrictransferrins

The kinetics of iron release from N-terminal and C-terminal monoferric human transferrins has been studied using EDTA as the accepting chelate. In the absence of added salts iron release from the N-terminal site is more facile but the relative lability can be reversed by the addition of NaClO₄, NaCl and LiCl. The results indicate that both anions and cations can affect the lability of the two sites. Since the relative lability of the two monoferrictransferrins is affected by fairly moderate concentrations of NaCl and NaClO₄ we suggest that the ionic composition serum may play an important role in determining the observed distribution of iron among the sites. A new method for the preparation of N-terminal monoferrictransferrin is described.     

Application of beta-irradiation through the struts of a previously deployed stent

The application of beta-radiation in coronary arteries is a promising new technique for the treatment of in-stent restenosis. This is the first case in which the 5 F. delivery catheter of the Beta-Cath trade mark system was advanced through the struts of a stent, previously deployed in an adjacent branch, so as to deliver radiation to the target vessel.     

Identification to the species level of <Emphasis Type="Italic">Lactobacillus</Emphasis> isolated in probiotic prospecting studies of human,animal or food origin by 16S-23S rRNA restriction profiling

Background  

The accurate identification of Lactobacillus and other co-isolated bacteria during microbial ecological studies of ecosystems such as the human or animal intestinal tracts and food products is a hard task by phenotypic methods requiring additional tests such as protein and/or lipids profiling.     

Lesion Load May Predict Long-Term Cognitive Dysfunction in Multiple Sclerosis Patients

Background

Magnetic Resonance Imaging (MRI) techniques provided evidences into the understanding of cognitive impairment (CIm) in Multiple Sclerosis (MS).

Objectives

To investigate the role of white matter (WM) and gray matter (GM) in predicting long-term CIm in a cohort of MS patients.

Methods

303 out of 597 patients participating in a previous multicenter clinical-MRI study were enrolled (49.4% were lost at follow-up). The following MRI parameters, expressed as fraction (f) of intracranial volume, were evaluated: cerebrospinal fluid (CSF-f), WM-f, GM-f and abnormal WM (AWM-f), a measure of lesion load. Nine years later, cognitive status was assessed in 241 patients using the Symbol Digit Modalities Test (SDMT), the Semantically Related Word List Test (SRWL), the Modified Card Sorting Test (MCST), and the Paced Auditory Serial Addition Test (PASAT). In particular, being SRWL a memory test, both immediate recall and delayed recall were evaluated. MCST scoring was calculated based on the number of categories, number of perseverative and non-perseverative errors.

Results

AWM-f was predictive of an impaired performance 9 years ahead in SDMT (OR 1.49, CI 1.12–1.97 p = 0.006), PASAT (OR 1.43, CI 1.14–1.80 p = 0.002), SRWL-immediate recall (OR 1.72 CI 1.35–2.20 p<0.001), SRWL-delayed recall (OR 1.61 CI 1.28–2.03 p<0.001), MCST-category (OR 1.52, CI 1.2–1.9 p<0.001), MCST-perseverative error(OR 1.51 CI 1.2–1.9 p = 0.001), MCST-non perseverative error (OR 1.26 CI 1.02–1.55 p = 0.032).

Conclusion

In our large MS cohort, focal WM damage appeared to be the most relevant predictor of the long-term cognitive outcome.     

Prospective Randomized Trial Comparing Hepatic Venous Outflow and Renal Function after Conventional versus Piggyback Liver Transplantation

Background

This randomized prospective clinical trial compared the hepatic venous outflow drainage and renal function after conventional with venovenous bypass (n = 15) or piggyback (n = 17) liver transplantation.

Methods

Free hepatic vein pressure (FHVP) and central venous pressure (CVP) measurements were performed after graft reperfusion. Postoperative serum creatinine (Cr) was measured daily on the first week and on the 14^th, 21^st and 28^th postoperative days (PO). The prevalence of acute renal failure (ARF) up to the 28th PO was analyzed by RIFLE-AKIN criteria. A Generalized Estimating Equation (GEE) approach was used for comparison of longitudinal measurements of renal function.

Results

FHVP-CVP gradient > 3 mm Hg was observed in 26.7% (4/15) of the patients in the conventional group and in 17.6% (3/17) in the piggyback group (p = 0.68). Median FHVP-CVP gradient was 2 mm Hg (0–8 mmHg) vs. 3 mm Hg (0–7 mm Hg) in conventional and piggyback groups, respectively (p = 0.73). There is no statistically significant difference between the conventional (1/15) and the piggyback (2/17) groups regarding massive ascites development (p = 1.00). GEE estimated marginal mean for Cr was significantly higher in conventional than in piggyback group (2.14 ± 0.26 vs. 1.47 ± 0.15 mg/dL; p = 0.02). The conventional method presented a higher prevalence of severe ARF during the first 28 PO days (OR = 3.207; 95% CI, 1.010 to 10.179; p = 0.048).

Conclusion

Patients submitted to liver transplantation using conventional or piggyback methods present similar results regarding venous outflow drainage of the graft. Conventional with venovenous bypass technique significantly increases the harm of postoperative renal dysfunction.

Trial Registration

ClinicalTrials.gov https://clinicaltrials.gov/ct2/show/NCT01707810     

Correlation between shell phenotype and local environment suggests a role for natural selection in the evolution of Placostylus snails

The giant edible Placostylus snails of New Caledonia occur across a wide range of environmental conditions, from the dry southwest to the wetter central and northeastern regions. In large, slow‐moving animals such as Placostylus, speciation could be assumed to be largely driven by allopatry and genetic drift as opposed to natural selection. We examined variation in shell morphology using geometric morphometrics and genetic structure within two species of Placostylus (P. fibratus, P. porphyrostomus), to determine the drivers of diversity in this group. Despite the current patchy distribution of snails on New Caledonia, both mtDNA and nuclear SNP data sets (>3000 loci) showed weak admixing between populations and species. Shell morphology was concordant with the genetic clusters we identified and had a strong relationship with local environment. The genetic data, in contrast to the morphological data, did not show concordance with climatic conditions, suggesting the snails are not limited in their ability to adapt to different environments. In sympatry, P. fibratus and P. porphyrostomus maintained genetic and morphological differences, suggesting a genetic basis of phenotypic variation. Convergence of shell shape was observed in two adjacent populations that are genetically isolated but experience similar habitat and climatic conditions. Conversely, some populations in contrasting environments were morphologically distinct although genetically indistinguishable. We infer that morphological divergence in the Placostylus snails of New Caledonia is mediated by adaptation to the local environment.     

Morphological differences among egg nests and adult individuals of Cicadatra persica (Hemiptera,Cicadidae), distributed in Erneh,Syria

The aim of this study is determining the different patterns of egg nests and the morphological differences between the specimens of Cicadatra persica Kirkalidy, 1909 (Hemiptera: Cicadidae) distributed in fruit orchards in Erneh located on AL-Sheikh mountain south west of Syria. The appearance of 80 egg nests was studied, and the results showed that there were two basic patterns of egg nests laid by Cicadatra persica, 90% of the egg nests were of the first pattern (consists of several adjacent slits), while 10% of them were of the second pattern (consists of several divergent slits). A random sample consisting of 300 specimens (150 males and 150 females) were also studied concentrating on the differences in the color of the supra-antennal plate and in the number of spurs on the tibia of the hind legs. The results showed that there were two basic patterns of individuals based on the differences in the color of supra-antennal plate. The first pattern (individuals with yellow supra-antennal plates), constituted more than 90%, and the second one (individuals with black supra-antennal plates) constituted less than 10%. The results also showed that there were 27 different patterns based on the number of spurs on the tibia of the hind legs. One of them was a common pattern (2, 3) whose individuals have 2 spurs on the upper side of the tibia of the hind legs and 3 spurs on the lateral side of the tibia of the hind legs. The total percent of this common pattern was 76%. The other 26 patterns were different from each other, and the total percent of all these different patterns was 24%.