Neophilometroides n. gen. (Nematoda: Philometridae) for Philometroides caudatus Moravec,Scholz and Vivas-Rodríguez, 1995, with erection of Neophilometroidinae n. subfam

A detailed examination (including scanning electron microscopy) of newly collected nematode specimens (subgravid females) referable to Philometroides caudatus Moravec, Scholz and Vivas-Rodríguez, 1995, from the swimbladder of the pimelodid catfish, Rhamdia guatemalensis, in the Papaloapan River in Tlacotalpan, State of Veracruz, Mexico, as well as the paratype specimens of this species, revealed the presence of a small buccal capsule armed with peribuccal teeth in the female. Because of this unique morphological feature within the Philometridae, and considering other taxonomically important characters such as the structure of the male tail and the shape of the anterior end of the esophagus in the gravid female, Neophilometroidinae n. subfam, and Neophilometroides n. gen. are proposed to accommodate this species. Philometra paraguayensis Petter, 1995, is transferred to Neophilometroides as N. paraguayensis (Petter, 1995) n. comb. Newly collected specimens are briefly described and illustrated.     

Chemokines: structure,receptors and functions. A new target for inflammation and asthma therapy?

Five to 10% of the human population have a disorder of the respiratory tract called 'asthma'. It has been known as a potentially dangerous disease for over 2000 years, as it was already described by Hippocrates and recognized as a disease entity by Egyptian and Hebrew physicians. At the beginning of this decade, there has been a fundamental change in asthma management. The emphasis has shifted from symptom relief with bronchodilator therapies (e.g. beta(2)-agonists) to a much earlier introduction of anti-inflammatory treatment (e.g. corticosteroids). Asthma is now recognized to be a chronic inflammatory disease of the airways, involving various inflammatory cells and their mediators. Although asthma has been the subject of many investigations, the exact role of the different inflammatory cells has not been elucidated completely. Many suggestions have been made and several cells have been implicated in the pathogenesis of asthma, such as the eosinophils, the mast cells, the basophils and the lymphocytes. To date, however, the relative importance of these cells is not completely understood. The cell type predominantly found in the asthmatic lung is the eosinophil and the recruitment of these eosinophils can be seen as a characteristic of asthma. In recent years much attention is given to the role of the newly identified chemokines in asthma pathology. Chemokines are structurally and functionally related 8-10 kDa peptides that are the products of distinct genes clustered on human chromosomes 4 and 17 and can be found at sites of inflammation. They form a superfamily of proinflammatory mediators that promote the recruitment of various kinds of leukocytes and lymphocytes. The chemokine superfamily can be divided into three subgroups based on overall sequence homology. Although the chemokines have highly conserved amino acid sequences, each of the chemokines binds to and induces the chemotaxis of particular classes of white blood cells. Certain chemokines stimulate the recruitment of multiple cell types including monocytes, lymphocytes, basophils, and eosinophils, which are important cells in asthma. Intervention in this process, by the development of chemokine antagonists, might be the key to new therapy. In this review we present an overview of recent developments in the field of chemokines and their role in inflammations as reported in literature.     

A Review of: “Bioseparations, (Downstream Processing for Biotechnology) P.A. Belter,E.L. Cussler and W.S. Hu,Wiley Interscience,New York, 1988; hardbound, 368 pages, $39.95”

ABSTRACT

Covalent structural information on membrane proteins is not easily acquired since it is difficult to obtain pure membrane proteins in sufficient quantities. We have therefore examined the Bio-Rad 491 prep cell continuous elution electrophoresis apparatus as a method for providing the quantities of purified , alpha and beta subunits from (Na.K)-ATPase required for these studies. Twenty-four milligrams of crude (Na.K)-ATPase preparation was applied to the prep cell which consisted of a 7% Laemmli separating gel 4.5 cm in length. The prep cell was Y run under constant power and continuous cooling conditions. Those fractions containing the beta subunit were combined and further purified by wheat germ agglutinin affinity"' chromatography. Fractions containing the alpha subunit were combined and did not require further purification. The identity and the degree of purity of the proteins obtained using this approach was assessed utilizing SDS-PAGE, amino acid analysis 375 Copyright 1993 by Marcel Dekker, Inc. * and N-tertninal sequencing. This simple and fast method provides approximately 1.8 milligrams of each purified subunit from 24 milligrams of relatively crude microsomes. Recovery of the alpha and beta subunits from the crude (Na.K)-ATPase preparation was estimated to be 28% and 81%, respectively.