Covalent immobilization of cellulose layers onto maleic anhydride copolymer thin films

Thin films of cellulose are advantageous for analytical studies in aqueous environments to investigate various factors determining the performance of cellulose-based products. However, the weak fixation of cellulose layers on common carrier materials often limits this approach. To address this problem, we suggest a novel maleic anhydride copolymer precoating technique which allows for the covalent attachment of cellulose thin films through esterification. Maleic anhydride copolymers were deposited and covalently bound onto planar, aminosilane-modified glass or silicon oxide surfaces. Cellulose was subsequently immobilized on top of the copolymer precoatings by spin coating from N-methylmorpholine-N-oxide/dimethyl sulfoxide solutions. The resulting cellulose films were thoroughly characterized with respect to layer thickness, morphology, chemical constitution, and electrical charging. The stability of the layers against shear stress was demonstrated in aqueous solutions and the covalent attachment of the cellulose to the copolymer films was proven by means of dissolution experiments followed by ellipsometry and high-resolution X-ray photoelectron spectroscopy.     

Genetic linkage and transmission disequilibrium of marker haplotypes at chromosome 1q41 in human systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by the production of autoantibodies to a wide range of self-antigens. Recent genome screens have implicated numerous chromosomal regions as potential SLE susceptibility loci. Among these, the 1q41 locus is of particular interest, because evidence for linkage has been found in several independent SLE family collections. Additionally, the 1q41 locus appears to be syntenic with a susceptibility interval identified in the NZM2410 mouse model for SLE. Here, we report the results of genotyping of 11 microsatellite markers within the 1q41 region in 210 SLE sibpair and 122 SLE trio families. These data confirm the modest evidence for linkage at 1q41 in our family collection (LOD = 1.21 at marker D1S2616). Evidence for significant linkage disequilibrium in this interval was also found. Multiple markers in the region exhibit transmission disequilibrium, with the peak single marker multiallelic linkage disequilibrium noted at D1S490 (pedigree disequilibrium test [PDT] global P value = 0.0091). Two- and three-marker haplotypes from the 1q41 region similarly showed strong transmission distortion in the collection of 332 SLE families. The finding of linkage together with significant transmission disequilibrium provides strong evidence for a susceptibility locus at 1q41 in human SLE.     

Genome screening in human systemic lupus erythematosus: results from a second Minnesota cohort and combined analyses of 187 sib-pair families

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by a loss of immunologic tolerance to a multitude of self-antigens. Epidemiological data suggest an important role for genes in the etiology of lupus, and previous genetic studies have implicated the HLA locus, complement genes, and low-affinity IgG (Fcgamma) receptors in SLE pathogenesis. In an effort to identify new susceptibility loci for SLE, we recently reported the results of a genomewide microsatellite marker screen in 105 SLE sib-pair families. By using nonparametric methods, evidence for linkage was found in four intervals: 6p11-21 (near the HLA), 16q13, 14q21-23, and 20p12.3 (LOD scores >/=2.0), and weaker evidence in another nine regions. We now report the results of a second complete genome screen in a new cohort of 82 SLE sib-pair families. In the cohort 2 screen, the four best intervals were 7p22 (LOD score 2.87), 7q21 (LOD score 2.40), 10p13 (LOD score 2.24), and 7q36 (LOD score 2.15). Eight additional intervals were identified with LOD scores in the range 1.00-1.67. A combined analysis of MN cohorts 1 and 2 (187 sib-pair families) showed that markers in 6p11-p21 (D6S426, LOD score 4.19) and 16q13 (D16S415, LOD score 3.85) met the criteria for significant linkage. Three intervals (2p15, 7q36, and 1q42) had LOD scores in the range 1.92-2.06, and another 13 intervals had LOD scores in the range of 1.00-1.78 in the combined sample. These data, together with other available gene mapping results in SLE, are beginning to allow a prioritization of genomic intervals for gene discovery efforts in human SLE.     

Uterotropic activity of cis and trans isomers of zearalenone and zearalenol

The cis and trans isomers of zearalenone [2,4-dihyroxy-6-(10-hydroxy-6-oxo-1-undecenyl)-benzoic acid mu-lactone] and zearalenol [2,4-dihydroxy-6-(6,10-dihydroxy-1-undecenyl)-benzoic acid mu-lactone] were tested for uterotropic activity in the white rat. The metabolites were administered through the oral route (per os) and by topical application to the freshly shaven skin on the back. cis-Zearalenone was significantly more active than trans when fed orally to the rats in the diet or when applied topically by skin application. However, the cis isomer of zearalenol was not significantly different than its trans isomer. trans-Zearalenone was less active than trans-zearalenol.     

Effect of Fatigue on Hamstring Reflex Responses and Posterior-Anterior Tibial Translation in Men and Women

Anterior cruciate ligament (ACL) rupture ranks among the most common injuries in sports. The incidence of ACL injuries is considerably higher in females than in males and the underlying mechanisms are still under debate. Furthermore, it has been suggested that muscle fatigue can be a risk factor for ACL injuries.We investigated gender differences in hamstring reflex responses and posterior-anterior tibial translation (TT) before and after fatiguing exercise. We assessed the isolated movement of the tibia relative to the femur in the sagittal plane as a consequence of mechanically induced TT in standing subjects. The muscle activity of the hamstrings was evaluated. Furthermore, isometric maximum voluntary torque (iMVT) and rate of torque development (RTD) of the hamstrings (H) and quadriceps (Q) were measured and the MVT H/Q as well as the RTD H/Q ratios were calculated.After fatigue, reflex onset latencies were enhanced in women. A reduction of reflex responses associated with an increased TT was observed in females. Men showed no differences in these parameters. Correlation analysis revealed no significant associations between parameters for TT and MVT H/Q as well as RTD H/Q.The results of the present study revealed that the fatigue protocol used in this study altered the latency and magnitude of reflex responses of the hamstrings as well as TT in women. These changes were not found in men. Based on our results, it is conceivable that the fatigue-induced decrease in neuromuscular function with a corresponding increase in TT probably contributes to the higher incidence of ACL injuries in women.     

Mustard gas surrogate, 2-chloroethyl ethylsulfide (2-CEES), induces centrosome amplification and aneuploidy in human and mouse cells

Mustard gas is a simple molecule with a deadly past. First used as a chemical weapon in World War I, its simple formulation has raised concerns over its use by terrorist organizations and unstable governments. Mustard gas is a powerful vesicant and alkylating agent that causes painful blisters on epithelial surfaces and increases the incidence of cancer in those exposed. The mechanism of mustard gas toxicity and tumorigenesis is not well understood but is thought to be mediated by its ability to induce oxidative stress and DNA damage. Interestingly, several proteins that have been shown to either be targets of mustard gas or mediate mustard gas toxicity have also been shown to regulate centrosome duplication. Centrosomes are small nonmembrane-bound organelles that direct the segregation of chromosomes during mitosis through the formation of the bipolar mitotic spindle. Cells with more or less than two centrosomes during mitosis can segregate their chromosomes unequally, resulting in chromosome instability, a common phenotype of cancer cells. In our studies, we show that subtoxic levels of 2-chloroethyl ethylsulfide (2-CEES), a mustard gas analog, induce centrosome amplification and chromosome instability in cells, which may hasten the mutation rate necessary for tumorigenesis. These data may explain why those exposed to mustard gas exhibit higher incidences of cancer than unexposed individuals of the same cohort.     

Food resource allocation patterns in lactating females in a long-term selection experiment for litter size in mice

Resource allocation patterns, as quantified by residual food intake (RFI), and the consequences for offspring development were investigated during lactation in 96 females of a mouse line selected for 104 generations for high litter size at birth (S-line) and in 87 females of a non-selected control line (C-line). Litters of 45 C-line dams (Cs) and 48 S-line dams (Ss) were standardised (s) at birth; other dams (ns) supported total number of pups born (Cns and Sns, respectively). RFI during lactation was significantly lower in Sns-dams than in C-line dams and Sns-dams. After weaning Sns-dams seemed to be able to restore the negative resource situation. Sns-pups were about 25% less mature than Cns-pups at all times. Maturity was similar for Cs- and Ss-pups from 2 d in lactation on, and about 18% and 53% higher than Cns- and Sns-pups. The pre-weaning mortality rate was significantly higher in Sns-litters (35.6 ± 2.76) than in Cns-litters (4.95 ± 2.23). The results suggest that S-line dams allocated considerably more resources to maintenance of offspring than C-line dams. This was insufficient to provide the offspring with an adequate amount of resources, resulting in reduced pup development and increased pre-weaning mortality rates.     

Effects on Turkey Poults of Rations Containing Corn Invaded by Fusarium tricinctum (Cda.) Sny. & Hans

Consumption of an otherwise balanced ration containing 1% of corn invaded by Fusarium tricinctum isolate 2061-C resulted in the death of 13% of turkey poults within 35 days, in decreased feed efficiency and weight gain, and moderate development of bilateral necrotic lesions at angles of the mouth, especially in those that succumbed. Consumption of a ration with 2% of corn invaded by F. tricinctum resulted in death of 60 to 83% of the birds, in greatly reduced growth and feed efficiency in the survivors, and in development of severe mouth lesions. Consumption of rations containing 5, 10, and 20% of corn invaded by the fungus resulted in death of all birds in 5 to 15 days.