Inhibitory action of natural carrageenans on Herpes simplex virus infection of mouse astrocytes

The effects of the carrageenans 1T1 (lambda-type), 1C1 (kappa/iota-type) and 1C3 (upsilon/nu-type), isolated from the red seaweed Gigartina skottsbergii, on herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infection of murine astrocytes were investigated. The three compounds were effective inhibitors of virus replication, as determined by a virus yield inhibition assay, in astrocytes as well as in Vero cells. The 50% inhibitory concentration was in the range of 0.9-3.6 and 0.4-3.2 microg/ml for astrocytes and Vero cells, respectively, whereas the 90% inhibitory concentration ranged from 6.5 to 17.0 microg/ml in astrocytes and from 3.5 to 22.2 microg/ml in Vero cells. No cytotoxicity was detected at concentrations of up to 1,000 microg/ml, indicating high selectivity indices for these compounds. Inhibition of viral cytopathology and antigen expression was also detected in the presence of the carrageenans. The increase in the expression of glial fibrillary acidic protein (GFAP), an activated astrocyte marker, produced during the course of HSV-1 infection in astrocytes, was reversed in the presence of 1C1 and 1C3. By contrast, the lambda-carrageenan 1T1 increased the expression of GFAP, independently of HSV-1 infection.     

Open reduction and intramedullary stabilisation of subtrochanteric femur fractures: A retrospective study of 56 cases

Subtrochanteric femur fractures commonly present with predictable displacement because of the deforming muscle forces acting upon the proximal femur. For this reason, successful closed reduction and femoral nailing can be a technically demanding procedure. Open reduction prior to nail placement has been advocated to improve and maintain anatomic fracture alignment. The purpose of this study was to evaluate the results of patients with closed subtrochanteric femur fractures treated with open reduction and a reamed antegrade statically locked intramedullary nail. An initial query of our database identified 154 patients who had sustained a subtrochanteric femur fracture over the defined study period. Ninety-six patients had adequate radiographic and clinical follow-up. Fifty-six (58%) patients were treated with open reduction and nail placement. There were no wound complications or infections and all patients went on to successful osseous union. There was no loss of reduction and a final coronal and sagittal plane deformity of <5 degrees in 55 of 56 (98%) patients. Open reduction of closed subtrochanteric femur fractures followed by intramedullary nailing leads to high union rates with rare complications.     

Upper digestive tract hemorrhage in cirrhotic patients

Sixteen clinical and biological variables were recorded in 116 episodes of upper digestive tract hemorrhage of known cause in cirrhotic patients. One-dimensional analysis reveals a significant correlation between six variables and the rupture of esophagogastric varices, whereas multiple linear regression and partial correlation analysis reduces the significant variables to two: a history of digestive hemorrhage and the nonalcoholic etiology of the cirrhosis. A value of the discriminant function exists for which the specificity and, consequently, the positive predictive value are equal to 100%, but with a sensitivity of 39%. These results mean that, in an explanatory approach, partial correlation analysis seems to constitute an indispensable complement to analysis of clinical and biological variables, since it reduces the chances of unwarranted explanatory interpretation. However, in a pragmatic approach, the recording of 16 variables does not permit a clear discrimination between ruptured varices and nonruptured varices; this suggests that either other factor(s) remain to be discovered or else that those related to ruptured varices and to acute ulcerations are the same.     

The ERP correlates of target checking are dependent upon the defining features of the prospective memory cues

In some contexts, prospective memory (PM) is thought to be dependent upon strategic monitoring of the environment for relevant cues. Behavioral data reveal that strategic monitoring is associated with slowing of response time for ongoing activity trials when a prospective component is added to the task, and functional imaging data reveal that monitoring is associated with recruitment of the anterior prefrontal cortex and other cortical structures. In the current study, event-related brain potentials (ERPs) were used to examine the neural correlates of target checking, one process underlying strategic monitoring. Consistent with previous research the behavioral data revealed a Stimulus Specific Interference Effect, wherein slowing of response time varied depending upon whether PM cues were words or nonwords. The ERP data also revealed that the neural correlates of target checking were sensitive to the defining features of the PM cues (i.e., were a word or nonword). When PM cues were words, the effect of target checking was associated with variation in ERP amplitude beginning around 100 ms after stimulus onset. In contrast, when PM cues were nonwords, the effect of target checking on the ERPs did not emerge until around 200 ms after stimulus onset. These data provide support for the multi-process view of PM by demonstrating that the pattern of neural recruitment related to target checking is sensitive to the defining characteristics of the PM cues.     

Effect of Ornamental Stone Waste Incorporation on the Rheology,Hydration, Microstructure,and CO2 Emissions of Ordinary Portland Cement

The ornamental stone industry generates large amounts of waste thus creating environmental and human health hazards. Thus, pastes with 0–30 wt.% ornamental stone waste (OSW) incorporated into ordinary Portland cement (OPC) were produced and their rheological properties, hydration kinetics, and mechanical properties were evaluated. The CO₂ equivalent emissions related to the pastes production were estimated for each composition. The results showed that the paste with 10 wt.% of OSW exhibited similar yield stress compared to the plain OPC paste, while pastes with 20 and 30 wt.% displayed reduced yield stresses up to 15%. OSW slightly enhanced the hydration kinetics compared to plain OPC, increasing the main heat flow peak and 90-h cumulative heat values. The incorporation of OSW reduced the 1-, 3-, and 28-days compressive strength of the pastes. Water absorption results agreed with the 28 days compressive strength results, indicating that OSW increased the volume of permeable voids. Finally, OSW incorporation progressively reduced the CO₂ emission per m³ of OPC paste, reaching a 31% reduction for the highest 30 wt.% OSW content. Overall, incorporating up to 10 wt.% with OSW led to pastes with comparable fresh and hardened properties as comported to plain OPC paste.     

Antimicrobial peptides: synthesis and antibacterial activity of linear and cyclic drosocin and apidaecin 1b analogues

Drosocin and apidaecin Ib are two insect antimicrobial peptides showing a significant sequence homology and a common mechanism of action, which includes stereoselective elements but is devoid of any pore-forming activity. A substantial difference between the two peptides is the presence in the drosocin sequence of an O-glycosylated threonine residue, which is important for its antimicrobial activity. Through the synthesis of a series of differently glycosylated drosocin analogues, we have shown that the antimicrobial activity against several Gram-negative bacteria appears to be modulated by the sugar moiety (Gal vs GalNAc) and the type of glycosidic linkage (alpha-O-, beta-O-, or alpha-C-). The insertion of a glycosylated threonine residue in the apidaecin Ib sequence improves the sequence homology with drosocin but reduces the antimicrobial activity. To gain information on the possible bioactive conformation of these peptides, we synthesized an unglycosylated cyclic analogue of drosocin, containing an intrachain disulfide bond, and the head-to-tail cyclic analogues of drosocin and apidaecin, as well as their corresponding cyclic dimers. Only the large cyclic dimer of apidaecin partially retained the antimicrobial activity, suggesting that a bending of the peptide chain, in particular in the middle of the molecule, is not a structural element characteristic of the bioactive conformation of drosocin and apidaecin. Experiments aimed at testing the effect of selected drosocin and apidaecin peptides on biological membranes showed that some peptides display a moderate hemolytic activity and that a dissociation between antibacterial activity and cytotoxicity to eukaryotic cells can be achieved in differently glycosylated peptide analogues.