Postoperative Depression of Tumour-directed Cell-mediated Immunity in Patients with Malignant Disease

Leucocytes from 46 melanoma patients, 45 breast carcinoma patients, and 95 control donors were tested by the leucocyte migration test against the supernatants of homogenates of malignant melanomas, breast carcinomas, simple breast tumours, and breasts showing simple cystic disease. By comparison with controls inhibition of migration occurred significantly more frequently when tumour patients'' leucocytes were exposed to extracts of histogenetically similar tumours.Cell-mediated immunity to tumour-associated antigens was measured in 12 patients with breast carcinoma and 12 with malignant melanoma immediately before surgical operation and in the postoperative period. All patients tested before operation showed significant inhibition of migration on contact with extracts of histogenetically similar tumours. Postoperatively the degree of leucocyte migration inhibition was reduced in all patients with melanoma and breast carcinoma. Significant inhibition of leucocyte migration returned in most patients 6-22 days after operation.     

Diversity of anaerobic gut fungal populations analysed using ribosomal ITS1 sequences in faeces of wild and domesticated herbivores

Gut fungal-specific PCR primers have been used to selectively amplify the ITS1 region of gut fungal rDNA recovered from faeces of domestic and wild animals to investigate population diversity. Two different gel-based methods are described for separating populations of gut fungal rDNA amplicons, namely (1) denaturing gradient gel electrophoresis (DGGE) and (2) separation according to small size differences using Spreadex, a proprietary matrix for electrophoresis. Gut fungal populations were characterised by analysis of rDNA in faeces of seventeen domesticated and ten wild herbivores. Sequences derived from these gel-based characterisations were analysed and classified using a hidden Markov model-based fingerprint matching algorithm. Faecal samples contained a broad spectrum of fungi and sequences from five of the six recognised genera were identified, including Cyllamyces, the most recently described gut fungal genus, which was found to be widely distributed in the samples. Furthermore, four other novel groupings of gut fungal sequences were identified that did not cluster with sequences from any of the previously described genera. Both gel- and sequence- based profiles for gut fungal populations suggested a lack of geographical restriction on occurrence of any individual fungal type.     

Five novel locations of Neocentromeres in human: 18q22.1, Xq27.1∼27.2, Acro p13, Acro p12, and heterochromatin of unknown origin

Since the first report in 1993, an ectopic centromere, i.e. neocentromere formation, has been reported in more than 100 small supernumerary marker chromosomes (sSMC), in 7 instances of centromere repositioning, and in about a dozen cases with more complex chromosomal rearrangements. Here we report 2 new cases with centromere repositioning and 3 neocentric sSMC consisting exclusively of heterochromatic material. Yet, no centromere formation was reported for the regions 18q22.1 and Xq27.1～27.2 as it was observed in the 2 cases with centromere repositioning here; in both cases, cytogenetically an inversion was suggested. Two of the 3 neocentric sSMC were derived from a short arm of an acrocentric chromosome. The remainder neocentric sSMC case was previously reported and was stainable only by material derived from itself.     

Efficiency of bacterial protein synthesis during anaerobic degradation of cattle waste

The rate of [15N]ammonia (15NH3) uptake or incorporation into bacterial cells was studied, using stirred, 3-liter benchtop digestors fed on a semicontinuous basis with cattle waste. The fermentations were carried out at 40 and 60 degrees C and at four different loading rates (3, 6, 9, and 12 g of volatile solids per liter of reactor volume per day). The rate of NH3-N incorporation for the period 1 to 5 h after feeding at the four different loading rates was 0.49, 0.83, 1.05, and 1.08 mg/liter per h in the mesophilic digestor and 0.68, 1.07, 1.17, and 1.21 mg/liter per h in the thermophilic digestor. Values were lower 7 to 21 h after feeding in both digestors and were related to the rate of fermentation or CH4 production. In the mesophilic digestors, the rate of bacterial cell production ranged from 3.97 to 8.72 mg of dry cells per liter per h, 1 to 5 h after feeding at the different loading rates. Corresponding values for the thermophilic digestors ranged from 5.46 to 9.77 mg of dry cells per liter per h. Cell yield values ranged from 2.3 to 3.1 mg of dry cells per mol of CH4 produced in the mesophilic and thermophilic digestors at the two lower loading rates. The values were higher (2.8 to 3.4) in the mesophilic digestors at the two higher loading rates because of the accumulation of propionate and a consequent reduction in CH4 production. Low cell yields such as those measured in this study are characteristic of low-specific-growth rates under energy-limited conditions.     

Tetracycline residues and tetracycline resistance genes in groundwater impacted by swine production facilities

Antibiotics are used at therapeutic levels to treat disease; at slightly lower levels as prophylactics; and at low, subtherapeutic levels for growth promotion and improvement of feed efficiency. Over 88% of swine producers in the United States gave antimicrobials to grower/finisher pigs in feed as a growth promoter in 2000. It is estimated that ca. 75% of antibiotics are not absorbed by animals and are excreted in urine and feces. The extensive use of antibiotics in swine production has resulted in antibiotic resistance in many intestinal bacteria, which are also excreted in swine feces, resulting in dissemination of resistance genes into the environment. To assess the impact of manure management on groundwater quality, groundwater samples have been collected near two swine confinement facilities that use lagoons for manure storage and treatment. Several key contaminant indicators - including inorganic ions, antibiotics, and antibiotic resistance genes - were analyzed in groundwater collected from the monitoring wells. Chloride, ammonium, potassium, and sodium were predominant inorganic constituents in the manure samples and served as indicators of groundwater contamination. Based on these analyses, shallow groundwater has been impacted by lagoon seepage at both sites. Liquid chromatography-mass spectroscopy (LC-MS) was used to measure the dissolved concentrations of tetracycline, chlortetracycline, and oxytetracycline in groundwater and manure. Although tetracyclines were regularly used at both facilities, they were infrequently detected in manure samples and then at relatively trace concentrations. Concentrations of all tetracyclines and their breakdown products in the groundwater sampled were generally less than 0.5 microg/L. Bacterial tetracycline resistance genes served as distinct genotypic markers to indicate the dissemination and mobility of antibiotic resistance genes that originated from the lagoons. Applying PCR to genomic DNA extracted from the lagoon and groundwater samples, four commonly occurring tetracycline (tet) resistance genes - tet(M), tet(O), tet(Q), and tet(W) - were detected. The detection frequency of tet genes was much higher in wells located closer to and down-gradient from the lagoons than in wells more distant from the lagoons. These results suggested that in the groundwater underlying both facilities tetracycline resistance genes exist and are somewhat persistent, but that the distribution and potentially the flux for each tet gene varied throughout the study period.     

Pyrosequencing-based analysis of the mucosal microbiota in healthy individuals reveals ubiquitous bacterial groups and micro-heterogeneity

This study used 16S rRNA-based pyrosequencing to examine the microbial community that is closely associated with the colonic mucosa of five healthy individuals. Spatial heterogeneity in microbiota was measured at right colon, left colon and rectum, and between biopsy duplicates spaced 1 cm apart. The data demonstrate that mucosal-associated microbiota is comprised of Firmicutes (50.9% ± 21.3%), Bacteroidetes (40.2% ± 23.8%) and Proteobacteria (8.6%± 4.7%), and that interindividual differences were apparent. Among the genera, Bacteroides, Leuconostoc and Weissella were present at high abundance (4.6% to 41.2%) in more than 90% of the studied biopsy samples. Lactococcus, Streptococcus, Acidovorax, Acinetobacter, Blautia, Faecalibacterium, Veillonella, and several unclassified bacterial groups were also ubiquitously present at an abundance <7.0% of total microbial community. With the exception of one individual, the mucosal-associated microbiota was relatively homogeneous along the colon (average 61% Bray-Curtis similarity). However, micro-heterogeneity was observed in biopsy duplicates within defined colonic sites for three of the individuals. A weak but significant Mantel correlation of 0.13 was observed between the abundance of acidomucins and mucosal-associated microbiota (P-value = 0.04), indicating that the localized biochemical differences may contribute in part to the micro-heterogeneity. This study provided a detailed insight to the baseline mucosal microbiota along the colon, and revealed the existence of micro-heterogeneity within defined colonic sites for certain individuals.     

Transcriptional Regulation of Cannabinoid Receptor-1 Expression in the Liver by Retinoic Acid Acting via Retinoic Acid Receptor-γ

Alcoholism can result in fatty liver that can progress to steatohepatitis, cirrhosis, and liver cancer. Mice fed alcohol develop fatty liver through endocannabinoid activation of hepatic CB₁ cannabinoid receptors (CB₁R), which increases lipogenesis and decreases fatty acid oxidation. Chronic alcohol feeding also up-regulates CB₁R in hepatocytes in vivo, which could be replicated in vitro by co-culturing control hepatocytes with hepatic stellate cells (HSC) isolated from ethanol-fed mice, implicating HSC-derived mediator(s) in the regulation of hepatic CB₁R (Jeong, W. I., Osei-Hyiaman, D., Park, O., Liu, J., Bátkai, S., Mukhopadhyay, P., Horiguchi, N., Harvey-White, J., Marsicano, G., Lutz, B., Gao, B., and Kunos, G. (2008) Cell Metab. 7, 227–235). HSC being a rich source of retinoic acid (RA), we tested whether RA and its receptors may regulate CB₁R expression in cultured mouse hepatocytes. Incubation of hepatocytes with RA or RA receptor (RAR) agonists increased CB₁R mRNA and protein, the most efficacious being the RARγ agonist CD437 and the pan-RAR agonist TTNPB. The endocannabinoid 2-arachidonoylglycerol (2-AG) also increased hepatic CB₁R expression, which was mediated indirectly via RA, because it was absent in hepatocytes from mice lacking retinaldehyde dehydrogenase 1, the enzyme catalyzing the generation of RA from retinaldehyde. The binding of RARγ to the CB₁R gene 5′ upstream domain in hepatocytes treated with RAR agonists or 2-AG was confirmed by chromatin immunoprecipitation and electrophoretic mobility shift and antibody supershift assays. Finally, TTNPB-induced CB₁R expression was attenuated by small interfering RNA knockdown of RARγ in hepatocytes. We conclude that RARγ regulates CB₁R expression and is thus involved in the control of hepatic fat metabolism by endocannabinoids.     

Midwater macroplankton of British Columbia studied by submersible PISCES IV

Data are reported from 30 dives during winter and spring 1980–83at sites in the Strait of Georgia and inlets running off it,and in inlets on the west coast of Vancouver Island. Observationswere made from the surface to the bottom (maximum 733 m) butmost attention was given to the midwater plankton community.The vertical distribution and abundance of hydromedusae, siphonophores,ctenophores, euphausiids, pelagic worms and molluscs were recordedsystematically, along with data for one copepod species (Neocalanusplumchrus). The midwater environment was found to be stablein terms of species composition and depth ranges, which permittedthe data for several years and many locations to be pooled.Four categories of plankton are recognized: (a) epipelagic (concentratedin the top 50 m); (b) mesopelagic (50–175 m); (c) bathypelagic(below 175 m); and (d) meso-bathypelagic (forms living in bothmeso- and bathypelagic zones). Species in this last categorybehave like mesopelagic forms at the upper end of their ranges,migrating to the surface at night. Deeper-lying members of thesame species do not migrate. For six such species, the cut-offpoint between migratory and non-migratory components was foundto lie at a mean depth of 175 m. This depth is therefore takenas the demarcation point between the meso- and bathypelagiczones. Taking account of published data on light penetration,it is estimated that, for the whole region, daytime light intensityat 175 m, and hence the effective limit for phototaxis of thespecies in question, lies in the range 10^–8–10^–9µW cm^–2.