A radioimmunoprecipitation method in the serodiagnosis of HIV infection: the development of the optimal conditions for its performance and the evaluation of the possibilities for its use

The optimum conditions for using the method of radioimmunoprecipitation (RIP) for the detection of human immunodeficiency virus (HIV) in serum samples have been established. Out of several available cell lines persistently infected with HIV, specially selected line 17 has been chosen. The characteristic feature of this is the high and stable (under the conditions of prolonged cultivation) accumulation of virus-specific proteins in infected cells. The optimum conditions for making the test and its evaluation have also been established. The data of literature on the advantages of the method of RIP over such traditional methods as the enzyme immunoassay and immunoblotting have been confirmed. Thus, the presence of specific antibodies in several serum samples registered as false negative has been established. The intertypical reactivity of two serotypes of the virus, HIV-1 and HIV-2, has been studied. Cross reactivity of antibodies with respect to the HIV gene gag, but not with respect to viral glycoproteids, has been established. Ideas on the expediency and prospects of using RIP for the serological control of HIV infection are presented.     

The ability of selected bacterial isolates to utilise components of synthetic metal-working fluids as sole sources of carbon and nitrogen for growth

A total of 24 bacterial isolates able to grow on metal-working fluids were obtained from soil or metal-working fluids (both in-use and heavily contaminated fluids). Pure cultures of the isolates were tested for their ability to degrade a selection of components, including borate esters, phosphate ester, biocide and triethanolamine, typically found in synthetic metal-working fluids. All components, when present at a level equivalent to half that found in an in-use metal-working fluid, supported growth when utilised as the sole source of carbon and/or nitrogen. Each component was degraded by at least 50% by an individual isolate within 120 hours in batch liquid culture.     

X-ray absorption spectroscopy of selenium-containing amino acids

Received: 2 April 1999 / Accepted: 17 September 1999     

High SEPT9_v1 Expression Is Associated with Poor Clinical Outcomes in Head and Neck Squamous Cell Carcinoma

The purpose of this work was to determine SEPT9_v1 expression levels in head and neck squamous cell carcinoma (HNSCC) and to analyze whether SEPT9_v1 expression is relevant to clinical outcomes. Recently, the SEPT9 isoform SEPT9_v1 has been implicated in oncogenesis, and methylation of the SEPT9 promoter region was reported in HNSCC. These findings led us to hypothesize that SEPT9_v1 could be differently expressed in HNSCC. To determine whether SEPT9_v1 is expressed in HNSCC, tissue microarray immunohistochemical analysis was performed using a SEPT9_v1-specific antibody. Tissue microarrays stained with a polyclonal SEPT9_v1-specific antibody was used to determine protein expression levels in HNSCC tissue samples, some with known clinical outcomes. This analysis showed that SEPT9_v1 is in fact highly expressed in HNSCC compared with normal epithelium, and high expression levels directly correlated with poor clinical outcomes. Specifically, a high SEPT9_v1 expression was associated with decreased disease-specific survival (P = .012), time to indication of surgery at primary site (P = .008), response to induction chemotherapy (P = .0002), and response to chemotherapy (P = .02), as well as advanced tumor stage (P = .012) and N stage (P = .0014). The expression of SEPT9_v1 was also strongly correlated with smoking status (P = .00094). SEPT9_v1 is highly expressed in HNSCC, and a high expression of SEPT9_v1 is associated with poor clinical outcomes. These data indicate that SEPT9_v1 warrants additional investigation as a potential biomarker for HNSCC.     

The development and ecology of the Japanese macaque gut microbiome from weaning to early adolescence in association with diet

Previously we have shown that the Japanese macaque gut microbiome differs not by obesity per se, but rather in association with high‐fat diet (HFD) feeding. This held true for both pregnant dams, as well as their 1‐year‐old offspring, even when weaned onto a control diet. Here we aimed to examine the stability of the gut microbiome over time and in response to maternal and postweaning HFD feeding from 6 months of age, and at 1 and 3 years of age. In both cross‐sectional and longitudinal specimens, we performed analysis of the V4 hypervariable region of the 16S rRNA gene on anus swabs collected from pregnant dams and their juveniles at age 6 months to 3 years (n = 55). Extracted microbial DNA was subjected to 16S‐amplicon‐based metagenomic sequencing on the Illumina MiSeq platform. We initially identified 272 unique bacterial genera, and multidimensional scaling revealed samples to cluster by age and diet exposures. Dirichlet multinomial mixture modeling of microbiota abundances enabled identification of two predominant enterotypes to which samples sorted, characterized primarily by Treponema abundance, or lack thereof. Approximating the time of initial weaning (6 months), the Japanese macaque offspring microbiome underwent a significant state type transition which stabilized from 1 to 3 years of age. However, we also found the low abundance Treponema enterotype to be strongly associated with HFD exposure, be it during gestation/lactation or in the postweaning interval. Examination of taxonomic co‐occurrences revealed samples within the low Treponema cluster were relatively permissive (allowing for increased interactions between microbiota) whereas samples within the high Treponema cluster were relatively exclusionary (suggesting decreased interactions amongst microbiota). Taken together, these findings suggest that Treponemes are keystone species in the developing gut microbiome of the gut, and susceptible to HFD feeding in their relative abundance.     

Enhanced biodecolorization of synthetic textile dye effluent by Phanerochaete chrysosporium under improved culture conditions

Biodecolorization of a synthetic commercial textile dye effluent (0.1 gl^–1) by Phanerochaete chrysosporium was enhanced by improving the original Kirk's medium with respect to buffer, C:N ratio, Mg²⁺ and Zn²⁺ ions, inoculum, temperature shifts, agitation and sunflower oil additon. An increase of 6.7-fold in lignin peroxidase (LIP) level, 4-fold in biomass and 45.5% enhanced decolorization of effluent was achieved. Degradation was both enzymatic (47.2%) and by biosorption (61.67%).     

Evaluation of the effect of closed areas on a unique and shallow water coral reef fish assemblage reveals complex responses

Areas closed to fishing are advocated as both fisheries management and biodiversity conservation tools. However, few studies investigate the responses of suites of both target and non-target fish species within an assemblage, which is an important consideration for ecosystem-based fisheries management approaches. Diver-operated stereo-video was used to assess the abundance and length of coral reef fish across multiple areas both open and closed to fishing at the Houtman Abrolhos Islands, Western Australia. After taking into consideration spatial differences in benthic habitat, the composition of fish assemblages was found to differ between open and closed areas. The target species, Plectropomus leopardus, was approximately two times more abundant in closed areas. Furthermore, 51 % of P. leopardus were larger than the minimum legal length (MLL) for retention in closed areas compared with only 1.8 % in areas open to fishing. Another target species, Choerodon rubescens was surveyed in greater abundance at sizes larger than the MLL in closed areas (64 % >400 mm) in comparison with areas open to fishing (36 %). A number of non-target species were also larger in closed areas (e.g., Kyphosus cornelii, Scarus schlegeli). In contrast, several non-targeted prey species were more abundant in open areas (e.g., Pomacentrus milleri was six times more abundant in open areas). Our results document complex responses of target and non-target species in closed areas at the Houtman Abrolhos Islands.     

The molecular basis of potassium nutrition in plants

Over the last five years, the cloning and characterization of K⁺ transport genes corresponding to K⁺ channels (KAT1, AKT1, KST1, AKT2), associated subunits (KAB1) and a high-affinity transporter (HKT1) has opened up important new avenues for research on plant K⁺ nutrition. With the abundance of molecular data now available it seems timely to link this information with the wealth of data previously accumulated on the physiology of plant K⁺ acquisition. The ultimate goal of all this research is to gain a better understanding of K⁺ transport and nutrition in the intact plant. Thus it is important to begin to integrate the molecular research with results from biochemical and physiological research conducted at the cellular, root and whole plant levels. This article will focus on describing the features of the cloned K⁺ transporters and their possible roles in mediating high- and low-affinity K⁺ uptake from the soil, as well as how K⁺ acquisition may be regulated.Abbreviations NEM N-ethyl maleimide - PCMBS p-chloromercuribenzene sulphonic acid     

An in situ study of beta-glucosidase activity in normal and gaucher fibroblasts with fluorogenic probes

Beta-glucosidase activity was evaluated in situ by means of fluorogenic probes in normal human fibroblasts and fibroblasts from homozygous carriers of the Gaucher trait. Probe internalization, targeting to lysosomes and post-cleavage probe retention were the primary concerns. Internalization and targeting were attempted by in situ photosensitized labilization of lysosomal membranes, lysosomotropic detergents and the use of low density lipid (LDL) or the receptor ligand apolipoprotein E (ApoE). Post-cleavage increase of fluorescence with fluoresceinyl (bis) betaglucopyranoside was appreciably above the rather large pre-cleavage emission. In cells incubated overnight with nonylumbelliferylbetaglucoside (UG9) in the presence of bovine serum albumin and in the absence of ApoE, the probe was dealt with as a cytotoxic agent, accumulating in a paranuclear cap, most likely comprising elements of the endoplasmic reticulum (ER) and Golgi apparatus. Targeting of UG9 to lysosomes occurred within 1 to 3 h of preincubation in the presence of ApoE. There was some evidence of specificity, as Gaucher fibroblasts exhibited weaker cleavage of UG9 (by 50 per cent or more) compared to normal fibroblasts, but in the Gaucher cells there was some residual beta-glucosidase activity. Cleavage of UG9 was nearly totally suppressed in Gaucher cells treated with the beta-glucosidase inhibitor, conduritol B epoxide, for 24 h to 7 days. Suppression in the control fibroblasts was evident but to a lesser degree. The in situ method of fluorogenic assay established for beta-glucosidase deficiency, is in principle applicable to enzyme deficiencies in other lysosomal storage diseases, or to evaluate enhanced enzyme activity following gene therapy.