Systematics within Gyps vultures: a clade at risk

Background  

Populations of the Oriental White-backed Vulture (Gyps bengalensis) have declined by over 95% within the past decade. This decline is largely due to incidental consumption of the non-steroidal anti-inflammatory veterinary pharmaceutical diclofenac, commonly used to treat domestic livestock. The conservation status of other Gyps vultures in southern Asia is also of immediate concern, given the lack of knowledge regarding status of their populations and the continuing existence of taxonomic uncertainties. In this study, we assess phylogenetic relationships for all recognized species and the majority of subspecies within the genus Gyps. The continuing veterinary use of diclofenac is an unknown but potential risk to related species with similar feeding habits to Gyps bengalensis. Therefore, an accurate assessment of the phylogenetic relationships among Gyps vultures should aid in their conservation by clarifying taxonomic uncertainties, and enabling inference of their respective relatedness to susceptible G. bengalensis.     

Determination of Poly-beta-Hydroxybutyrate and Poly-beta-Hydroxyvalerate in Activated Sludge by Gas-Liquid Chromatography

A convenient gas-liquid chromatography procedure to quantify poly-beta-hydroxybutyrate and poly-beta-hydroxyvalerate in activated sludge was developed by combining lyophilization of the samples, purification of the chloroform phase by water reextraction, and the use of capillary columns. With a flame ionization detector the sensitivity was estimated at 10 g/liter.     

Combination biotherapy utilizing interleukin-2 and alpha interferon in patients with advanced cancer: a National Biotherapy Study Group Trial.

The National Biotherapy Study Group (NBSG) conducted a broad phase II trial using interleukin-2 (IL-2) by continuous infusion and alpha interferon (IFN) subcutaneously in 267 patients with a variety of advanced cancers, including 29 with breast cancer, 89 with renal cancer, and 69 with melanoma. IL-2 [18 million international units (MIU)/m2] was given by continuous infusion for 108 hours with 3 mu/m2 subcutaneous IFN every other day during the IL-2 infusion. The patients were treated for 1 week followed by a 2-week rest. After two cycles of treatment, patients were evaluated for response. Of the 237 patients evaluable for response, 20 (8%) had a complete or partial response and 128 (54%) were stable. Therefore, 62% of the evaluable patients were nonprogressive during the first 90 days of IL-2/IFN therapy. The objective response rate was 11% in melanoma, 7% in renal cancer, 14% in breast cancer, and 3% in patients with a variety of malignancies for an overall response rate of 7% in these patients with advanced cancer. The patients were treated on a general medical ward and tolerated treatment well with fatigue and fever being nearly universal. Dyspnea, pruritus, chills, and elevated creatinines were frequent but less common. This combination biotherapy regimen has minimal activity in a variety of advanced cancers and must be compared with the best existing chemotherapy for each cancer type in randomized, prospective trials.     

Adhesion, penetration and intracellular replication of Legionella pneumophila: an in vitro model of pathogenesis

Legionella pneumophila attached to, penetrated and replicated within the three eukaryotic cell lines, MRC-5, HEp-2 and Vero. Multiplication occurred rapidly in these cells for an initial 48 h after inoculation and declined thereafter. Infected MRC-5 cell monolayers developed lytic-type cytopathic changes, with organisms being readily released. HEp-2 cells showed a more chronic infection, with slowly developing granular changes in the monolayers, and slow release of intracellular bacteria. In Vero cells, organisms were released rapidly along with a more progressively developing granular cytopathic effect in the monolayers. L. pneumophila was unable to grow in cell-free culture fluids. Uptake and intracellular development was similar for each cell type, and was initiated by 'bacteriopexis', a process in which the organisms bound via receptors and were surrounded by cellular microvilli which eventually fused, leading to bacterial engulfment. Replication of organisms in vacuoles within the cytoplasm of infected cells was confirmed by thorium labelling. These vacuoles were lined with ribosomes and, at the early stages of intracellular development, were found in close proximity to mitochondria, cytoplasmic filaments and banded enclosures. Ruthenium red staining showed that acid mucopolysaccharide capsular material was not present on these organisms during the attachment process or intracellular phase. Organism release was by lysis of the infected cells.     

Patterns of divergence during evolution of alpha 1-proteinase inhibitors in mammals

alpha 1-Proteinase inhibitor (alpha 1-PI), a member of the serine proteinase inhibitor superfamily, has a primary role in controlling neutrophil elastase activity within the mammalian circulation. Several studies have indicated that the reactive center region of alpha 1-PI, the amino acid sequence of which is critical to recognition of and binding to target proteinases, is highly divergent within and among species. This appears to be a consequence of accelerated rates of evolution that may have been driven by positive Darwinian selection. In order to examine this and other features of alpha 1-PI evolution in more detail, we have isolated and sequenced cDNAs representing alpha 1- PI mRNAs of the mouse species Mus saxicola and Mus minutoides and have compared these with a number of other mammalian alpha 1-PI mRNAs. Relative to other mammalian mRNAs, the extent of nonsynonymous substitution is generally high throughout the alpha 1-PI mRNA molecule, indicating greater overall rates of amino acid substitution. Within and among mouse species, the 5'-half of the mRNA, but not the 3'-half, has been homogenized by concerted evolution. Finally, the reactive center is under diversifying or positive Darwinian selection in murid rodents (rats, mice) and guinea pigs yet is under purifying selection in primates and artiodactyls. The significance of these findings to alpha 1-PI function and the possible selective forces driving evolution of serpins in general are discussed.      

Anaerobic acidogenesis of primary sludge: the role of solids retention time

This research investigates the effect of solids retention time (SRT) on the acid-phase anaerobic digestion of primary sludge. A series of experiments were conducted using two continuous-flow 3-L units with the following configuration: a completely mixed reactor (CMR) with clarifier and solids recycle and an upflow anaerobic sludge blanket (UASB) reactor. Results show that C(2) to C(5) volatile fatty acids (VFA) were the predominant compounds formed. At a constant hydraulic retention time (HRT) of 12 h, variation in SRT from 10 to 20 days resulted in a slight increase in VFA production in both systems, but at a shorter SRT (5 days) a drastic drop in acid production was observed. In addition, the percent distribution of VFA was to some extent affected by the change in SRT. On the other hand, organic matter degradation [measured by the chemical oxygen demand (COD) specific solubilization rate or the percent volatile suspended solids (VSS) reduction] appeared to be independent of SRT, at least in the range investigated. The percent soluble COD in the form of VFA, however, increased steadily with increasing SRT, approaching the 90% level at 20 days. The remaining soluble COD in the effluent from these systems may be mainly attributed to metabolic intermediates and unused soluble substrate. (c) 1994 John Wiley & Sons, Inc.