Assessment of histogenesis and proliferative potential in cytologic specimens of human brain tumors. Value of immunocytochemistry and nucleolar organizer regions.

The value of immunocytochemistry and nucleolar organizer regions (NORs) for the histogenetic identification and the estimation of the proliferative potential of brain tumors was assessed by the investigation of imprint smears of 51 neurosurgical tumor specimens. A panel of five monoclonal antibodies was used to cover a broad range of immunohistochemical markers. For the assessment of NORs, a silver staining technique (AgNOR) was used. NORs were enumerated and measured by means of an interactive image analysis system. The immunocytochemical results were similar for the smears and paraffin-embedded sections for 95.6% of the investigations performed and for 76.2% of the cases. Glial fibrillary acidic protein (GFAP) was positive in 9 of 17 tumors of glial origin, but was negative in 9 metastatic tumors. Vimentin was positive in 10 of 10 and fibronectin in 9 of 10 meningiomas investigated. The number of NORs increased steadily with the increasing grade of malignancy. Especially in glioblastomas, the number of NORs per cell exhibited a wide range, which might reflect the heterogeneity of these neoplasms. Metastases revealed a higher number of NORs per cell than did glioblastomas. In the cytologic differential diagnosis of these tumors, an absence of GFAP expression combined with a high NOR count is suggestive of a metastatic tumor.     

Occupancy modelling as a new approach to assess supranational trends using opportunistic data: a pilot study for the damselfly Calopteryx splendens

There is limited information available on changes in biodiversity at the European scale, because there is a lack of data from standardised monitoring for most species groups. However, a great number of observations made without a standardised field protocol is available in many countries for many species. Such opportunistic data offer an alternative source of information, but unfortunately such data suffer from non-standardised observation effort and geographical bias. Here we describe a new approach to compiling supranational trends using opportunistic data which adjusts for these two major imperfections. The non-standardised observation effort is dealt with by occupancy modelling, and the unequal geographical distribution of sites by a weighting procedure. The damselfly Calopteryx splendens was chosen as our test species. The data were collected from five countries (Ireland, Great Britain, the Netherlands, Belgium and France), covering the period 1990–2008. We used occupancy models to estimate the annual number of occupied 1 × 1 km sites per country. Occupancy models use presence-absence data, account for imperfect detection of species, and thereby correct for between-year variability in observation effort. The occupancy models were run per country in a Bayesian mode of inference using JAGS. The occupancy estimates per country were then aggregated to assess the supranational trend in the number of occupied 1 × 1 km². To adjust for the unequal geographical distribution of surveyed sites, we weighted the countries according to the number of sites surveyed and the range of the species per country. The distribution of C. splendens has increased significantly in the combined five countries. Our trial demonstrated that a supranational trend in distribution can be derived from opportunistic data, while adjusting for observation effort and geographical bias. This opens new perspectives for international monitoring of biodiversity.     

Overwintering locations and hosts for onion thrips (Thysanoptera: Thripidae) in the onion cropping ecosystem in New York

Identifying locations where onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), overwinter and subsequently disperse is important for designing control strategies. In upstate New York from 2003 through 2006, potential overwintering sites in the commercial onion, Allium cepa L., cropping system were investigated early in the spring before onion seedling emergence and again late in the season after onions were harvested. Onion thrips adults were sampled directly from the soil and indirectly from the soil by using emergence cages. Sampling locations included onion field interiors and edges and areas outside of these fields, including woods. Host material sampled included onion culls; volunteer onions, which sprout from cull onions left behind after harvest; and weeds. Onion thrips adults were found in all sections of onion fields and in locations outside of onion fields, with the fewest emerging from woods. Emergence began in early May and extended into June. Peak emergence occurred during the last half of May, at which time 50-75% of the population had emerged. Adults colonized volunteer onions as early as late March and as late as mid-November. No adults were found overwintering in onion cull piles. Adults also colonized several weed species, especially pigweed, Amaranthus hybridis L., and lambsquarters, Chenopodium album L., late in the fall. Our results indicate that onion thrips adults overwinter in the soil within and near onion fields and that they probably colonize volunteer onion plants before subsequent generations infest the onion crop in the spring. Volunteer onions and weeds also provide onion thrips with a host after onions are harvested. Consequently, onion thrips management strategies should include tactics that reduce volunteer onion and weed abundance.     

Synthesis and in vitro muscarinic activities of a series of 1,3-diazacycloalkyl carboxaldehyde oxime derivatives

A series of 1,3-diazacycloalkyl carboxaldehyde oxime derivatives was synthesized and tested for muscarinic activity in receptor binding assays using [3H]-oxotremorine-M (OXO-M) and [3H]-pirenzepine (PZ) as ligands. Potential muscarinic agonistic or antagonistic properties of the compounds were determined using binding studies measuring their potencies to inhibit the binding of OXO-M and PZ. Preferential inhibition of OXO-M binding was used as an indicator for potential muscarinic agonistic properties; this potential was confirmed in functional studies on isolated organs.     

Functional Analysis of Glycoprotein L (gL) from Rhesus Lymphocryptovirus in Epstein-Barr Virus-Mediated Cell Fusion Indicates a Direct Role of gL in gB-Induced Membrane Fusion

Glycoprotein L (gL), which complexes with gH, is a conserved herpesvirus protein that is essential for Epstein-Barr virus (EBV) entry into host cells. The gH/gL complex has a conserved role in entry among herpesviruses, yet the mechanism is not clear. To gain a better understanding of the role of gL in EBV-mediated fusion, chimeric proteins were made using rhesus lymphocryptovirus (Rh-LCV) gL (Rh gL), which shares a high sequence homology with EBV gL but does not complement EBV gL in mediating fusion with B cells. A reduction in fusion activity was observed with chimeric gL proteins that contained the amino terminus of Rh gL, although they retained their ability to process and transport gH/gL to the cell surface. Amino acids not conserved within this region in EBV gL when compared to Rh gL were further analyzed, with the results mapping residues 54 and 94 as being functionally important for EBV-mediated fusion. All chimeras and mutants displayed levels of cell surface expression similar to that of wild-type gL and interacted with gH and gp42. Our data also suggest that the role of gL involves the activation or recruitment of gB with the gH/gL complex, as we found that reduced fusion of Rh gL, EBV/Rh-LCV chimeras, and gL point mutants could be restored by replacing EBV gB with Rh gB. These observations demonstrate a distinction between the role of gL in the processing and trafficking of gH to the cell surface and a posttrafficking role in cell-cell fusion.Epstein-Barr virus (EBV) is a member of the lymphocryptovirus (LCV) subgroup of gammaherpesviruses and primarily infects epithelial and B lymphocytes, where it establishes productive and latent infections, respectively (8, 40). EBV is extremely prevalent in humans, with more than 90% of the population being infected. Following primary infection, EBV persists in a latent state in memory B lymphocytes, where it can remain indefinitely (3, 43). The expansion and proliferation of these cells can lead to the development of a number of EBV-related malignancies, including tumors of lymphoid tissues, such as Hodgkin''s lymphoma, Burkitt''s lymphoma, and some T-cell lymphomas, as well as tumors associated with epithelial tissues, such as nasopharyngeal carcinoma and gastric carcinoma (5, 32, 36, 48). EBV is also associated with lymphoproliferative disorders in immunocompromised patients, such as oral hairy leukoplakia and posttransplant lymphoproliferative disorders (12, 15, 43, 45).Herpesvirus entry is a multistep process that includes the initial binding of the virus to the cell surface, interaction with a cellular entry receptor, membrane-virion fusion, and internalization of the virion (40). The enveloped membrane of EBV contains numerous glycoproteins that are necessary for mediating attachment and the subsequent fusion between viral and cell membranes, although the required glycoproteins differ for epithelial and B-cell infection (13, 22). Infection of B cells is initiated upon the binding of EBV glycoprotein gp350/220 to the CD21/CR2 cellular receptor expressed on target cells (9, 27, 41). Following the initial binding, viral glycoprotein gp42 binds to human leukocyte antigen class II (HLA class II) and triggers fusion, which is mediated by the concerted actions of glycoproteins gB, gH, and gL (21, 41). Glycoproteins gH and gL form a heteromeric complex that is conserved among the herpesvirus family despite a low degree of sequence homology in gH and gL across herpesviruses (33, 40). The gH/gL complex has an essential role in entry of herpesviruses, yet the exact role of each protein is not well understood. The role of gH is thought to be in cell fusion, while gL mediates processing and transport of gH to the cell surface (34, 35, 47, 51). Since gL is generally essential for the proper processing and transport of gH in all herpesviruses, it has been difficult to examine the role of gL separate from gH.While little is known about the role of gL in EBV-mediated fusion, data from studies of other herpesviruses have suggested a more direct role of gL in fusion. Antibodies specific for the C terminus of herpes simplex virus (HSV) gL, mapped to residues 168 to 224, were found to inhibit fusion with some strains of HSV type 1 (HSV-1), suggesting a role of this region in fusion (28). Deletion analysis of HSV-1 gL determined that the first 161 amino acids of gL are sufficient for binding gH, and further deletion identified the region between amino acids 155 and 161 of HSV-1 gL as critical for gH transport and cell fusion (19, 20, 33). Together, the results of these studies suggest that the inhibition of fusion observed with gL antibodies (Abs) is not due to an inhibition of gH/gL complex formation. Another study found that mutations to the amino-terminal region of HSV-2 gH permitted transport of the glycoprotein to the cell surface independent of gL but that gL was still required for fusion, suggesting a role of gL in fusion after the complex has trafficked to the plasma membrane (6). Most recently, the results of an investigation of the functional homology of the primate rhesus LCV (Rh-LCV) gL (Rh gL) suggest that gL may have a functional role in EBV fusion with B cells. Rh gL shares a high degree of sequence similarity with EBV (81.6%), and yet, the glycoprotein was unable to mediate fusion with human B cells when expressed with either EBV gH or Rh gH, even though the gH/gL complex was detected on the cell surface and Rh gL could associate with gH and gp42 (31). The LCV that infects rhesus primates is biologically similar to EBV in that it shares a similar genome organization, repertoire of lytic and latent genes, and pathogenesis (7, 25, 37, 46).To gain a better understanding of the role of gL in EBV-mediated fusion with B cells, we constructed chimeric gL proteins that included portions of Rh gL inserted into the sequence of EBV gL. We identified the amino terminus of EBV gL as being functionally necessary in mediating fusion with B cells, and this role is distinguishable from the role of gL in the processing and transport of gH to the cell surface. Single and double point mutations were constructed in both EBV and Rh gL, and our results indicated that residues 54 and 94 are functionally critical in mediating fusion with B cells. Interestingly, our studies also identified a species-specific reliance between gL and gB, suggesting a possible association between these two glycoproteins that is necessary in mediating fusion. Thus, our studies demonstrated that EBV gL has a more substantial role in mediating fusion with B cells that is distinct from its role in the processing and trafficking of gH.     

On the possibility of oral treatment with protein solutions

Experiments on animals showed that native proteins may diffuse into the blood flow after oral administration of diluted protein solutions. An in vitro study led us to hypothesize that treatment with diluted solutions is accompanied by a decrease in the rate of protein proteolysis and accelerated protein diffusion through the intestinal mucosa.