Population monitoring in support of a rabies vaccination program for skunks in Arizona

Three population monitoring methods were evaluated in support of a trap/vaccinate/release program for controlling a bat variant of rabies virus in skunks (Mephitis mephitis) in Flagstaff, Arizona (USA). Skunks were the primary species targeted for population monitoring during the program, but feral cats were also monitored as they represented an abundant secondary vector species capable of rabies transmission. Skunks were vaccinated and released, except for a subset tested for rabies. All captured cats were placed in the local animal shelter. Spotlight surveys essentially did not detect skunks, and were not able to detect reductions in the cat population. Catch-per-unit-effort marginally tracked population trends, but a passive track index adapted for an urban setting was most sensitive for detecting changes in skunk and cat populations. Mark-recapture population estimates could not be validly calculated from the data on captures and recaptures due to multiple violations of analytical assumptions.     

On the Origin of Rheumatoid Arthritis: The Impact of Environment and Genes—A Population Based Twin Study

Background

Rheumatoid arthritis (RA) is an autoimmune disease with a complex origin. Previous studies have reported heritability estimates on RA at about 60%. Only 16% of the genetic background of the disease has been disclosed so far. The purpose of the present investigation was to provide an optimized estimate on the heritability of RA and to study the recurrence risk in a nationwide Caucasian twin population.

Methods and Findings

In a mail survey addressed to 56.707 twin individuals, RA was reported by 479 individuals, mean age 52 (range 16–73). Respondents underwent an interview and clinical examination. Ascertainment probability was 80%. RA was confirmed in 162 twin individuals yielding a prevalence at 0.37% (95% CI 0.31–0.43). The mean discordance time was 19 years (range 0–57). The concordance was 9.1% (95% CI 1.9 to 24.3) in MZ, 6.4% (95% CI 2.1 to 14.3) in DZss. The increased relative risk of attracting RA conditioned on having an affected cotwin compared to the background population risk was 24.6 to 35.4 in MZ twins and 17.3 to 31.6 in DZss twins. The correlation coefficients were 0.60 (0.33 to 0.78) in monozygotic (MZ) and 0.55 (0.33 to 0.72) in dizygotic same sexed (DZss) pairs. Twelve percent (95% CI 0–76%) of the phenotypic variance in the liability to RA was due to additive genetic effects, 50% (95% CI 0–72%) to shared environmental effects and 38% (95% CI 17–61%) to non-shared environmental effects.

Conclusions

This study emphasizes that family factors are important for the development of RA. Although genetic effectors are important, shared and non-shared environmental triggers and/or epigenetic stochastic events seem to be even more significant. However, it should be borne in mind that the genetic and non-genetic components may not be the same across disease subsets.     

Mechanisms of Topoisomerase I (TOP1) Gene Copy Number Increase in a Stage III Colorectal Cancer Patient Cohort

Background

Topoisomerase I (Top1) is the target of Top1 inhibitor chemotherapy. The TOP1 gene, located at 20q12-q13.1, is frequently detected at elevated copy numbers in colorectal cancer (CRC). The present study explores the mechanism, frequency and prognostic impact of TOP1 gene aberrations in stage III CRC and how these can be detected by fluorescent in situ hybridization (FISH).

Methods

Nine CRC cell line metaphase spreads were analyzed by FISH with a TOP1 probe in combination with a reference probe covering either the centromeric region of chromosome 20 (CEN-20) or chromosome 2 (CEN-2). Tissue sections from 154 chemonaive stage III CRC patients, previously studied with TOP1/CEN-20, were analyzed with TOP1/CEN-2. Relationships between biomarker status and overall survival (OS), time to recurrence (TTR) in CRC and time to local recurrence (LR; rectal cancer only) were determined.

Results

TOP1 aberrations were observed in four cell line metaphases. In all cell lines CEN-2 was found to reflect chromosomal ploidy levels and therefore the TOP1/CEN-2 probe combination was selected to identify TOP1 gene gains (TOP1/CEN-2≥1.5). One hundred and three patients (68.2%) had TOP1 gain, of which 15 patients (14.6%) harbored an amplification (TOP1/CEN-20≥2.0). TOP1 gene gain did not have any association with clinical endpoints, whereas TOP1 amplification showed a non-significant trend towards longer TTR (multivariate HR: 0.50, p = 0.08). Once amplified cases were segregated from other cases of gene gain, non-amplified gene increases (TOP1/CEN-2≥1.5 and TOP1/CEN-20<2.0) showed a trend towards shorter TTR (univariate HR: 1.57, p = 0.07).

Conclusions

TOP1 gene copy number increase occurs frequently in stage III CRC in a mechanism that often includes CEN-20. Using CEN-2 as a measurement for tumor ploidy levels, we were able to discriminate between different mechanisms of gene gain, which appeared to differ in prognostic impact. TOP1 FISH guidelines have been updated.     

Isolation and characterization of<Emphasis Type="Italic"> Erythrobacter</Emphasis> sp. strains from the upper ocean

Seven strains of marine aerobic anoxygenic phototrophs belonging to the genus Erythrobacter were isolated. The strains were characterized regarding their physiological and biochemical properties, 16S rDNA and pufM gene sequences, morphological features, substrate preference, as well as pigment and lipid composition. All strains had functional type-2 reaction centers containing bacteriochlorophyll, served by small, light-harvesting complex 1, and were photosynthetically competent. In addition, large pools of carotenoids were found, but only some of the accessory pigments transfer energy to the reaction centers. All of the isolates were facultative photoheterotrophs. They required an organic carbon substrate for growth; however, they are able to supplement a significant fraction of their metabolic requirements with photosynthetically derived energy.Abbreviations BChl Bacteriochlorophyll - Chl Chlorophyll - Erb. Erythrobacter - Erm. Erythromicrobium - FAMEs Fatty acid methyl esters - IRFRR Infrared fast repetition rate - LH1, LH2 Light-harvesting complex 1 and 2, respectively - Por. Porphyrobacter - PUFAs Polyunsaturated fatty acids - Rsb. Roseobacter - RubisCO Ribulose-1,5-bisphosphate carboxylase/oxygenase - µ Growth rate - ₄₇₀ Functional cross-section of the photosynthetic unit at 470 nm     

Preclinical model to test human papillomavirus virus (HPV) capsid vaccines in vivo using infectious HPV/cottontail rabbit papillomavirus chimeric papillomavirus particles

A human papillomavirus (HPV) vaccine consisting of virus-like particles (VLPs) was recently approved for human use. It is generally assumed that VLP vaccines protect by inducing type-specific neutralizing antibodies. Preclinical animal models cannot be used to test for protection against HPV infections due to species restriction. We developed a model using chimeric HPV capsid/cottontail rabbit papillomavirus (CRPV) genome particles to permit the direct testing of HPV VLP vaccines in rabbits. Animals vaccinated with CRPV, HPV type 16 (HPV-16), or HPV-11 VLPs were challenged with both homologous (CRPV capsid) and chimeric (HPV-16 capsid) particles. Strong type-specific protection was observed, demonstrating the potential application of this approach.     

Long-term impacts of selective logging on two Amazonian tree species with contrasting ecological and reproductive characteristics: inferences from Eco-gene model simulations

The impact of logging and subsequent recovery after logging is predicted to vary depending on specific life history traits of the logged species. The Eco-gene simulation model was used to evaluate the long-term impacts of selective logging over 300 years on two contrasting Brazilian Amazon tree species, Dipteryx odorata and Jacaranda copaia. D. odorata (Leguminosae), a slow growing climax tree, occurs at very low densities, whereas J. copaia (Bignoniaceae) is a fast growing pioneer tree that occurs at high densities. Microsatellite multilocus genotypes of the pre-logging populations were used as data inputs for the Eco-gene model and post-logging genetic data was used to verify the output from the simulations. Overall, under current Brazilian forest management regulations, there were neither short nor long-term impacts on J. copaia. By contrast, D. odorata cannot be sustainably logged under current regulations, a sustainable scenario was achieved by increasing the minimum cutting diameter at breast height from 50 to 100 cm over 30-year logging cycles. Genetic parameters were only slightly affected by selective logging, with reductions in the numbers of alleles and single genotypes. In the short term, the loss of alleles seen in J. copaia simulations was the same as in real data, whereas fewer alleles were lost in D. odorata simulations than in the field. The different impacts and periods of recovery for each species support the idea that ecological and genetic information are essential at species, ecological guild or reproductive group levels to help derive sustainable management scenarios for tropical forests.     

A novel Epac-specific cAMP analogue demonstrates independent regulation of Rap1 and ERK

cAMP is involved in a wide variety of cellular processes that were thought to be mediated by protein kinase A (PKA). However, cAMP also directly regulates Epac1 and Epac2, guanine nucleotide-exchange factors (GEFs) for the small GTPases Rap1 and Rap2 (refs 2,3). Unfortunately, there is an absence of tools to discriminate between PKA- and Epac-mediated effects. Therefore, through rational drug design we have developed a novel cAMP analogue, 8-(4-chloro-phenylthio)-2'-O-methyladenosine-3',5'-cyclic monophosphate (8CPT-2Me-cAMP), which activates Epac, but not PKA, both in vitro and in vivo. Using this analogue, we tested the widespread model that Rap1 mediates cAMP-induced regulation of the extracellular signal-regulated kinase (ERK). However, both in cell lines in which cAMP inhibits growth-factor-induced ERK activation and in which cAMP activates ERK, 8CPT-2Me-cAMP did not affect ERK activity. Moreover, in cell lines in which cAMP activates ERK, inhibition of PKA and Ras, but not Rap1, abolished cAMP-mediated ERK activation. We conclude that cAMP-induced regulation of ERK and activation of Rap1 are independent processes.     

Chemically methylated and reduced pectins: preparation,characterisation by 1H NMR spectroscopy,enzymatic degradation,and gelling properties

The gelling properties of pectins are known to be closely related to the degree of methylation (DM) and the distribution of the ester groups. In order to investigate this dependency, a natural citrus pectin (DM 64%) has been methylated to pectins with higher DM or saponified to achieve pectins with lower DM. A simple method for determination of DM by 1H NMR spectroscopy is presented. New modified pectins have been prepared by treatment of pectins having different DM with NaBH(4) to reduce selectively the methyl esters to primary alcohols in the presence of free acids. The degree of reduction (DR) and the DM of the remaining carboxylic acids could likewise be determined by 1H NMR spectroscopy. The new reduced pectins are recognized by the pectin degrading enzymes polygalacturonase PGI and PGII as well as by pectin lyase, all from Aspergillus niger, but the enzymes exhibit lower specific activities as compared with unmodified pectin. The new reduced pectins exhibit high gelling properties.     

Long-term effects of polyacrylamide hydrogel on human breast tissue

Polyacrylamide hydrogel is an atoxic, stable, nonresorbable sterile watery gel consisting of approximately 2.5% cross-linked polyacrylamide and nonpyrogenic water. Polyacrylamide hydrogel is widely used in ophthalmic operations, drug treatment, food packaging products, and water purification. In the former Soviet Union, polyacrylamide hydrogel has been used in plastic and aesthetic surgery for more than 10 years, and Kiev City Hospital treats approximately 300 women a year for breast augmentation using the polyacrylamide hydrogel Interfall (Contura SA, Montreux, Switzerland). Capsule shrinkage following these injections has never been observed. The authors examined breast tissue samples from a total of 27 women who had polyacrylamide hydrogel injected at Kiev City Hospital up to 8 years and 10 months earlier. Age at operation, duration of polyacrylamide hydrogel implantation, history of possible side effects to the gel injection, other intercurrent diseases, the reason for present open breast operation, and breast palpation findings before operation were in each case compared with the histological findings on samples taken from breast tissue bordering the gel. The gel presented itself as a dark violet, homogenous mass with a rounded or ragged outline in large or medium-size deposits and as elongated strands, which mimicked the extracellular matrix, in small deposits. Histological findings of the breast tissue bordering the gel showed three different patterns: large collections of gel gave rise to a thick, soft-looking cellular membrane of macrophages and foreign-body giant cells; medium-size deposits were surrounded by just a thin layer of macrophages; and small deposits were not associated with any reaction in the surrounding tissue. Projections of the cellular soft membrane, known as granulomas, were seen in six patients. The granulomas were composed of macrophages, foreign-body giant cells, lymphocytes, and blood cells. A thin layer of fibrous connective tissue was occasionally present around the foreign-body membrane, but the thick fibrous capsule, which has been described in connection with silicone implants, was completely absent. The gel changes could be correlated to neither time since gel injection nor a history of recent injury or inflammation. It is concluded that the polyacrylamide hydrogel Interfall, which has been used in the former Soviet Union, is stable over time, nondegradable, confined to the breast, and diffusion and migration resistant. When the hydrogel is injected in medium-size or large quantities a cellular foreign-body reaction occurs, but in small amounts it is capable of splitting up individual connective tissue fibers and fat cells, substituting for the extracellular connective tissue matrix without eliciting any foreign-body reaction. As far as these data are concerned, polyacrylamide hydrogel is well tolerated by the breast and does not give rise to severe fibrosis, pain, or capsule shrinkage. However, to determine safety with more certainty, a larger sample size would be necessary.