A linkage group with FRA16B (the fragile site at 16q22.1)

Summary Polymorphic DNA markers located in bands 16q13, 16q21 and 16q22 were examined for recombination with FRA16B, the fragile site at 16q22.100. A tight linkage cluster D16S10-FRA16B-D16S4-HP was established. There were no recombinants between D16S10 and D16S4, which flank FRA16B. The markers D16S10 and D16S4 are in close proximity on the genetic map and delineate a small chromosomal segment, which contains the distamycin A-inducible fragile site.     

Applicable methods of reconstruction for the replacement of soft tissue after the radical resection of oral tumors

In Hungary the number of oral and pharyngeal cancers is alarmingly high. While the mortality rate in 1955 was 282, by 2005 it rose to 1567. However, in the last 1-2 years stagnation can be observed. Nevertheless, even now significant proportions of men and women are involved. Alcohol consumption and smoking are invariably the leading causes, but one cannot disregard the shortcomings of oral cancer screenings, either. Unfortunately, drastic changes in this field are not likely to occur in the near future. Numerous solutions have been developed for the replacement of soft tissue. In our article, we describe and evaluate four of them. When using these techniques, we were often successful in replacing soft tissue deficiencies.     

Transient forebrain ischemia increases the blood-brain barrier permeability for albumin in stroke-prone spontaneously hypertensive rats

1. The aim of the present study was to reveal the effect of transient forebrain ischemia on the regional and temporal changes in the permeability of the blood-brain barrier (BBB) permeability for sodium fluorescein (MW: 376 Da) and Evan's blue-labeled albumin (MW: 67 kDa) in stroke-prone spontaneously hypertensive rats (SHRSP).2. BBB permeability was significantly higher in the brain regions of 16-week-old control SHRSP than those in age-matched normotensive Wistar-Kyoto rats.3. Transient forebrain ischemia evoked by 10-min bilateral carotid occlusion increased the permeability of the BBB for albumin, but not for sodium fluorescein, after 6 and 24 h of reperfusion in brain regions of SHRSP.4. Extravasation of serum macromolecules may contribute to neuronal loss and development of hypertensive encephalopathy in SHRSP.     

The molecular basis of X-linked spondyloepiphyseal dysplasia tarda

The X-linked form of spondyloepiphyseal dysplasia tarda (SEDL), a radiologically distinct skeletal dysplasia affecting the vertebrae and epiphyses, is caused by mutations in the SEDL gene. To characterize the molecular basis for SEDL, we have identified the spectrum of SEDL mutations in 30 of 36 unrelated cases of X-linked SEDL ascertained from different ethnic populations. Twenty-one different disease-associated mutations now have been identified throughout the SEDL gene. These include nonsense mutations in exons 4 and 5, missense mutations in exons 4 and 6, small (2-7 bp) and large (>1 kb) deletions, insertions, and putative splicing errors, with one splicing error due to a complex deletion/insertion mutation. Eight different frameshift mutations lead to a premature termination of translation and account for >43% (13/30) of SEDL cases, with half of these (7/13) being due to dinucleotide deletions. Altogether, deletions account for 57% (17/30) of all known SEDL mutations. Four recurrent mutations (IVS3+5G-->A, 157-158delAT, 191-192delTG, and 271-275delCAAGA) account for 43% (13/30) of confirmed SEDL cases. The results of haplotype analyses and the diverse ethnic origins of patients support recurrent mutations. Two patients with large deletions of SEDL exons were found, one with childhood onset of painful complications, the other relatively free of additional symptoms. However, we could not establish a clear genotype/phenotype correlation and therefore conclude that the complete unaltered SEDL-gene product is essential for normal bone growth. Molecular diagnosis can now be offered for presymptomatic testing of this disorder. Appropriate lifestyle decisions and, eventually, perhaps, specific SEDL therapies may ameliorate the prognosis of premature osteoarthritis and the need for hip arthroplasty.     

Quecksilber in Federn des Sperbers(Accipiter nisus) aus dem Erzgebirge

Zusammenfassung In der vorliegenden Arbeit wird der Quecksilbergehalt von 48 Mauserfedern (Hand- und Armschwingen) des Sperbers aus dem Erzgebirge (Freistaat Sachsen, BRD) untersucht. Die Federn stammen von 37 Weibchen und wurden zwischen 1980 und 1998 gesammelt. Zum Vergleich dienen fünf Federproben von Museumspräparaten, die vor 1930 auf dem Gebiet des Freistaates Sachsen gesammelt wurden. Die Federproben wurden mit der Hamburger Protonenmikrosonde analysiert. Die Quecksilbergehalte der Mauserfedern des selben Vogels können relativ große Unterschiede aufweisen (n=3 ). Eine deutliche Reduktion der Hg-Konzentration mit fortschreitender Handschwingenmauser zeigte nur ein Weibchen. Als Vergleichswert für eine Hg-Grundbelastung vor 1930 wurden 2,7 ppm Hg (n=5) ermittelt. Die in den 1980er Jahren stark angestiegenen Konzentrationswerte (x_G=22,6 ppm, n=25) fielen 1997/98 auf 4,0 ppm Hg (n=10) ab, was auf eine Verringerung des anthropogenen Quecksilbereintrages in die Umwelt nach 1990 schließen lässt. Regionale Kontaminationsunterschiede zeichneten sich zwischen dem Gebiet der Großstadt Chemnitz und dem höher belasteten Umland ab (1980–1990). Die höchsten Quecksilbergehalte wurden in Sperberfedern aus dem Bereich Niederwiesa-Flöha-Falkennau festgestellt (Landkreis Freiberg).

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Mercury in the feathers of the Sparrowhawk(Accipiter nisus) from the Erz Mountains

Summary The present paper examines the concentration of mercury in 48 moult-feathers (primaries and secondaries) of the Sparrowhawk from the Erzgebirge region (province of Saxony, Germany). The feathers were collected from 37 females between 1980 and 1998. Five feather-samples of museum-preparations, collected in the area of the federal state of Sachsen before 1930, serve to provide a comparison with times with a low Hg use. All samples were analysed by the Hamburg proton micro-probe. The mercury contents of the moultfeathers from the same bird showed relatively great differences (n=3 ). Only one female showed a clear reduction of the Hg concentration with the progressive moult of the primaries. The feather-samples, collected before 1930, contained 2.7 ppm mercury (n=5). The concentration increased in the eighties up to 22.6 ppm (n=25) and decreased to 4.0 ppm in 1997/98. There was a reduction of the amount of mercury entering the environment as a result of human activities after 1990. Regional deviations of contamination were characteristic between the area of the city Chemnitz and the highly contaminated surroundings (1980–1990). The highest mercury concentration was established in the moult-feathers from the region of Niederwiesa-Flöha-Falkenau (county Freiberg, 1990).

     

Rational design of complex phenotype via network models

We demonstrate a modeling and computational framework that allows for rapid screening of thousands of potential network designs for particular dynamic behavior. To illustrate this capability we consider the problem of hysteresis, a prerequisite for construction of robust bistable switches and hence a cornerstone for construction of more complex synthetic circuits. We evaluate and rank most three node networks according to their ability to robustly exhibit hysteresis where robustness is measured with respect to parameters over multiple dynamic phenotypes. Focusing on the highest ranked networks, we demonstrate how additional robustness and design constraints can be applied. We compare our results to more traditional methods based on specific parameterization of ordinary differential equation models and demonstrate a strong qualitative match at a small fraction of the computational cost.     

Hantavirus Transmission in Sylvan and Peridomestic Environments

We developed a compartmental model for hantavirus infection in deer mice (Peromyscus maniculatus) with the goal of comparing relative importance of direct and indirect transmission in sylvan and peridomestic environments. A direct transmission occurs when the infection is mediated by the contact of an infected and an uninfected mouse, while an indirect transmission occurs when the infection is mediated by the contact of an uninfected mouse with, for instance, infected soil. Based on population dynamics data and estimates of hantavirus decay in the two types of environments, our model predicts that direct transmission dominates in the sylvan environment, while both pathways are important in peridomestic environments. The model allows us to compute a basic reproduction number R ₀, which indicates whether the virus will be endemic or eradicated from the mouse population, in both an autonomous and a time-periodic model. Our analysis can be used to evaluate various eradication strategies.     

Mechanical Allodynia Circuitry in the Dorsal Horn Is Defined by the Nature of the Injury

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Interstitial cells from the atrial and ventricular sides of the bovine mitral valve respond differently to denuding endocardial injury

Summary The mitral valve has atrial and ventricular sides, each lined by endocardial cells. The valve stroma contains α smooth muscle actin positive interstitial cells, collagen, glycosaminoglycans, and elastic tissue. To eliminate the effect of endocardium on wound repair in bovine mitral valve organ culture, the endocardium was removed from both sides of the valve. At 6 days, organ cultures of these preparations revealed surface cells on the ventricular side but not on the atrial side. Ventricular surface cells were negative for Factor VIII-related antigen, and positive for α smooth muscle actin. Immuno-peroxidase staining for proliferating cell nuclear antigen/cyclin, a marker for cell proliferation, revealed a positive labeling index of (mean ± standard deviation) 0.08 ± 0.16% for interstitial cells from the atrial side and 0.14 ± 0.19% for ventricular side interstitial cells in uncultured preparations (not significant), and 0.44 ± 0.69% for atrial side interstitial cells and 2.25 ± 1.64% for ventricular side interstitial cells in the cultured preparations (significant,P<0.0006). The results suggest that in organ culture, interstitial cells from the ventricular side of the mitral valve respond to a denuding endocardial injury by proliferating and migrating onto the adjacent surface whereas interstitial cells from the atrial side do not. This difference in the response to injury of interstitial cells from the atrial and ventricular sides of the valve may reflect differences in phenotype or may be due to effects of extracellular matrix on interstitial cell behavior. The latter is possible because of differences in the extracellular matrix of the atrial and ventricular sides of the valve.     

Senescence and antibiotic resistance in an age-structured population model

Different theories have been proposed to understand the growing problem of antibiotic resistance of microbial populations. Here we investigate a model that is based on the hypothesis that senescence is a possible explanation for the existence of so-called persister cells which are resistant to antibiotic treatment. We study a chemostat model with a microbial population which is age-structured and show that if the growth rates of cells in different age classes are sufficiently close to a scalar multiple of a common growth rate, then the population will globally stabilize at a coexistence steady state. This steady state persists under an antibiotic treatment if the level of antibiotics is below a certain threshold; if the level exceeds this threshold, the washout state becomes a globally attracting equilibrium.