Effect of Fast Electron Irradiation on Electrical and Optical Properties of CdGeAs2 and ZnGep2

We report on the effects of fast electron irradiation on the optical absorption (α) of CdGeAs2and ZnGeP2 and on the electrical properties of CdGeAs2. In p-CdGeAs2 irradiation led to the reduction in α and an increase in the electrical resistivity. The lowest values of α (about 0.1 cm' at 5µm<λ<10µm) were obtained on irradiated crystals of p-type with the highest degree of compensation. Further accumulation of the electron dose caused conversion to n-type and deterioration of the optical transmission. In ZnGeP2 irradiation caused a decrease in a at λ>0.85 λm and increase in α at λ<0.85 μm. At λ=2.05 μm, α for the o-ray could be reduced to less than 0.08 cm−1. At higher doses, saturation in α was observed. The effects of irradiation are discussed in connection with possible mechanisms of optical absorption in CdGeAs2 and ZnGeP2.

Use of bone marrow micrometastasis to predict disease-free and overall survival in esophageal cancer: Evaluation of 304 cases

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Background: The presence of bone marrow micrometastases (BMM) yields prognostic information for patients at higher risk for recurrence and death. Aim of the study was to evaluate the role of BMM in esophageal cancer (EC). Methods: 304 consecutive patients operated for EC and with BMM status were included into the prospective study. BMM were assessed by a pan-anti- cytokeratin monoclonal antibody, A45-B/B3. Associations between BMM status and clinicopathological parameters as well as disease-free (DFS) and overall survival (OS) were calculated with chi-square-, log-rank test and Cox multivariate analysis. Results: Out of 304 patients 109 (35.9%) were BMM positive (BMM+) and 195 (64.1%) negative (BMM-). Significant correlation was found between BMM and tumor size, nodal stage and recurrence (P=0.02, 0.002 and <0.0001). DFS and OS were significantly better in BMM- compared to BMM+ patients (median 44.2 and 31.6 vs. 10.4 and 12.4 months, P<0.0001). Sub-analyses revealed that nodal negative (N-) patients with BMM- had a significant better DFS and OS compared to N- and BMM+ patients (50.8 and 41.5 vs. 18.0 and 16.3 months, P<0.0001). Nodal positive patients (N+) with BMM- had a better DFS and OS compared to N+ and BMM+ patients (22.1 and 24.8 vs. 9.0 and 11.3 months, P<0.0001). In the Cox multivariate analysis BMM was the strongest predictor of DFS and OS with a hazard ratio of 3.1 and 2.9 (P<0.0001). Also tumor size and nodal stage were found to be significant predictors, whereas age and sex were not. All analyses were repeated after stratification of the study group to underlying tumor type (adenocarcinoma (AC) and squamous cell carcinoma (SCC)). Significant differences were found at all levels as reported for the entire study group above within the AC and SCC group as well. Conclusions: To our knowledge this is the largest study evaluating the role of BMM in EC. Survival sub-analyses stratified to nodal and bone marrow status revealed a significant role of BMM in EC. Presence of BMM proved to be the strongest predictor of DFS and OS in AC and SCC of the esophageus.

No significant financial relationships to disclose.

Noninvasive coronary angiography by contrast-enhanced electron beam computed tomography

Electron beam computed tomography (EBCT) is a cross-sectional imaging method with high temporal and spatial resolution. So far, it has mainly been applied for the detection of coronary artery calcifications which permit the very sensitive detection of coronary atherosclerosis even in the very early stages. However, after intravenous injection of a contrast agent, EBCT also permits the direct visualization of the coronary artery lumen. For these investigations, a volume data set is acquired that consists of 40 axial cross-sections of the heart (3 mm slice thickness). To evaluate the coronary arteries as to the presence of stenoses and occlusions, various forms of post-processing, including shaded surface display, maximum intensity projection, and multiplanar reconstruction, are applied. The sensitivities and specificities for the detection of coronary artery stenoses and occlusions are about 90%. Best results are obtained for coronary artery bypass grafts, the left main coronary artery, and the left anterior descending coronary artery, while reduced image quality impairs the results for the right coronary artery and the left circumflex coronary artery.

[Arterio-venous aneurysm of splenic vessels--a rare differential diagnosis for cardio-circulatory symptoms]

Patients with arterio-venous fistula of the splenic hilum seek medical assistance because of abdominal discomfort and symptoms of portal hypertension. We report on a 43 year old female who was diagnosed with an arterio-venous aneurysm after suffering from dyspnoea, tachycardia and extrasystolies for several years. After uncomplicated distal splenopancreatectomy the patient was discharged free of symptoms.

Randomized placebo-controlled trial of a flavonoid-rich plant extract-based cream in the treatment of rosacea

BACKGROUND

Biological research suggests that vascular changes may play a major role in rosacea pathogenesis. Chrysanthellum indicum is a plant-based extract containing a unique combination of phenylpropenoic acids, flavonoids and saponosids, and has a well-documented effect on vascular wall permeability and increase of the mechanical resistance of capillaries.

OBJECTIVE

To determine the efficacy and safety of a cream containing 1%C. indicum extract with vitamin P properties in the treatment of rosacea.

METHODS

This study included 246 patients diagnosed clinically as having moderate rosacea. Patients were randomly allocated to C. indicum extract-based cream (n = 125) and placebo (n = 121) groups. Patients were advised to apply the products on their face twice a day for a 12-week period. The patients were examined at the end of each 4-week period. Severity of erythema (graded by reference to six photographs), surface of erythema and rosacea overall severity scores were recorded at each visit on days 0, 28, 56 and 84. Investigators carried out a final efficacy assessment at the end of week 12. Volunteers' final overall efficacy assessment was recorded in a self-administered questionnaire. Adverse events were identified through examination, interview and collection of comments in patients' questionnaires.

RESULTS

Treatment with the C. indicum extract-based cream resulted in significant improvement (P < 0.05) in severity of erythema, overall rosacea severity compared to baseline and placebo, and investigator and patient overall efficacy assessment scores (P = 0.046 and P = 0.001, respectively) compared with placebo scores. Adverse reactions were mild, and did not differ between the C. indicum extract-based cream and the placebo groups.

CONCLUSION

Chrysanthellum indicum extract-based cream is an effective and well-tolerated topical agent for the treatment of moderate rosacea. The mode of action of the active ingredient suggests that additional efficacy might be expected from combination with other topical treatments.

QTL mapping for a trade-off between leaf and bud production in a recombinant inbred population of Microseris douglasii and M. bigelovii (Asteraceae, Lactuceae): a potential preadaptation for the colonization of serpentine soils

The different response to growth on serpentine soil is a major autecological difference between the annual asteracean species Microseris douglasii and M. bigelovii, with nearly non-overlapping distribution ranges in California. Early flowering and seed set is regarded as a crucial character contributing to escape drought and thus is strongly correlated with survival and reproductive success on serpentine as naturally toxic soil. M. bigelovii (strain C94) from non-serpentine soil produces more leaves at the expense of bud production in the first growing phase than M. douglasii (B14) from serpentine soil. A QTL mapping study for this trade-off and for other growth-related traits was performed after six generations of inbreeding (F7) from a single interspecific hybrid between B14 and C94 on plants that were grown on serpentine and alternatively on normal potting soil. The trade-off is mainly correlated with markers on one map region on linkage group 03a (lg03a) with major phenotypic effects (phenotypic variance explained [PVE] = 18.8 - 31.7 %). Plants with the M. douglasii allele in QTL-B1 (QTL-NL1) produce more buds but fewer leaves in the first 119 days on both soil types. Three modifier QTL could be mapped for bud and leaf production. In one modifier (QTL-B2 = QTL-NL4) the M. douglasii allele is again associated with more buds but fewer leaves. QTL mapped for bud set in the F6 co-localize with QTL-B1 (major QTL) and QTL-B3. Two additional QTL for leaf length and red coloration of leaves could be mapped to one map region on lg03a. Co-localization of the two QTL loci with major phenotypic effects on bud and leaf production strongly suggests that a major genetic locus controls the trade-off between the two adaptive traits. The importance of mutational changes in major genes for the adaptation to stressful environments is discussed.

Geographic distribution and recombination of genomic fragments on the short arm of chromosome 2 of Arabidopsis thaliana

Range expansion from Pleistocene refugia and anthropogenic influences contribute to the present distribution pattern of Arabidopsis thaliana. We scored a genome-wide set of CAPSs and found two markers with an east-west geographic distribution across the Eurasian range of the species. Regions around the two SNPs were sequenced in 98 accessions, including newly collected plants from Middle Asia and Western Siberia. These regions correspond to a gene ( approximately 1500 bp) and a non-coding region ( approximately 500 bp) 300 kbp apart on chromosome 2. Nucleotide diversities, pi, of the two sequenced fragments were 0.0032 and 0.0130. The haplotypes of both sequences belonged to one of two groups: a rather uniform "Asian" and a more variable "European" haplotype group, on the basis of non-disjunct clusters of SNPs. Recombination between "Asian" and "European" haplotypes occurs where they meet. Especially in the "European" haplotype, many rare SNP variants representing independent mutations are scattered among the shared haplotype-specific SNPs. This agrees with previous suggestions of two large haplotype groups in A. thaliana and the post-glacial colonization of central Europe from the east and the west. A clear correlation between climatic factors and the haplotype distribution may reflect the dispersal history rather than local climate adaptation. The pattern of SNP variation within the contiguous sequences explains why only a minority of SNPs selected across the genome show evidence of this geographic pattern.

QTL mapping reveals a two-step model for the evolutionary reduction of inner microsporangia within the asteracean genus Microseris

The reduction of inner (adaxial) pollen sacs (microsporangia, MS) as a diagnostic character for the three asteracean species, Microseris bigelovii, Microseris elegans and Microseris pygmaea, was analysed in an interspecific cross between Microseris douglasii and Microseris bigelovii with 4 MS and 2 MS, respectively, using the average number of MS per plant as a quantitative character. A previous QTL (Quantitative Trait Locus) analysis had revealed one major QTL (3B) and three modifier QTLs (3A, 4A, 7A) with epistatic effects only on the homozygous recessive 2 MS genotype of QTL 3B. Here we performed a bulked segregant analysis on four 2 MS and four 4 MS DNA-bulks with 407 EcoRI/ MseI AFLP-primer combinations each. In this way additional AFLP markers were mapped close to QTL 3B and QTL 3A. Three of them were converted to SCAR (Sequence Characterized Amplified region) markers. All markers were tested in natural populations of the disporangiate (2 MS) species M. bigelovii, M. elegans and M. pygmaea, and in different populations of tetrasporangiate (4 MS) M. douglasii. The marker distribution suggests that locus 3B mutated in a progenitor of the disporangiate species. QTL 3A has evolved in the 2 MS background of the major gene in the disporangiate species. Since M. pygmaea and M. bigelovii are the sister group to M. elegans, the 4 MS genotype for (markers of) QTL 3A in M. pygmaea populations is most likely due to a back mutation to the 4 MS state and could explain the slight instability of the 2 MS phenotype in this species.

Prediction of in vivo hepatic clearance from in vitro data using cryopreserved human hepatocytes

1. Cryopreserved human hepatocytes were used to predict in vivo hepatic clearance (CL(hepatic)) from estimates of in vitro intrinsic clearance (CL' int). 2. (CL' int) was estimated for phenytoin, valproic acid, carbamazepine, theophylline, quinidine and procainamide after their addition to hepatocytes suspended either in human serum or in serum-free media. (CL' int)was estimated from in vitro concentration versus time data fitted to a monoexponential decay model. (CL' int) was estimated from concentrations measured at four time points and from just two-point measures, namely the initial concentration (C(0)) and the final concentration measurement (C(last)). 3. Predicted CL(hepatic) was within twofold of reported in vivo values of CL(hepatic) for all substrates. Moreover, predictions were not significantly different whether derived from hepatocytes suspended in serum or in serum-free medium. 4. Two-point estimates of (CL' int) were just as accurate in predicting CL(hepatic) as were multipoint estimates of (CL' int). 5. Although the data set was limited, the findings suggest that the measurement of the disappearance of xenobiotics from serum or serum-free media in which primary human hepatocytes have been suspended provides a physiologically relevant estimate of hepatic clearance that can be employed early in the drug development process to eliminate xenobiotics with unacceptable clearances.

Genetic structure of a population sample of apomictic dandelions

In Northern Europe, dandelion populations consist solely of triploid or higher polyploid apomicts. Without a regular sexual cycle or lateral gene transmission, a clonal structure is expected for Taraxacum apomicts, although this was not found by compatibility analysis. In this study, we investigate whether this observation could be suported by performing independent tests based on data from hypervariable microsatellite markers as well as more conservative data based on allozymes and matrilinear cpDNA markers. In addition, population genetic methods were used to test departure from panmictic expectations, which is expected for clonal populations. Results indicated that many data sets, again, did not agree with expectations from clonal evolution because only small groups of genotypes exhibit no marker incompatibility. Population genetic analysis revealed that virtually all genotypes, but not individuals, agreed with random segregation and genotypic equilibria. Exceptions were genotypes with rare allozyme alleles or nearly identical microsatellite genotypes. Consequently, a population sample of apomictic dandelions essentially harbours genotypes that resulted from segregation and/or recombination and only a few genotypes that may have differentiated by somatic mutations.

[Vasoconstriction of retinal arterioles with oxygen breathing in diabetic retinopathy]

OBJECTIVES

The retinal vessel analyzer (RVA) offers the unique opportunity of noninvasive online measurements of retinal vessel diameters. Breathing 100% oxygen is used to test vessel contractility of retinal arterioles in different stages of diabetic retinopathy (DR).

METHODS

After a 3-min baseline measurement 40 patients with diabetes were exposed to 100% oxygen breathing for a 5-min period. The diameter of a retinal arteriole was measured with the RVA continuously during this time. Subjects were divided into four groups according to different stages of DR. Group I: no RD; group II: mild/moderate RD; group III: moderate/severe nonproliferative RD with laser treatment; group IV: proliferative RD with laser treatment.

RESULTS

Group I (n=12) demonstrated a vasoconstriction of 6.2% (+/-4.0). In group II (n=8) 6.1% (+/-2.8) and in group III (n=8) 6.6% (+/-4.1) vasoconstriction was found. Group IV (n=12) presented a vasodilatation of +2.5% (+/-4,7).

CONCLUSION

No significant differences could be found in the vasoreaction to 100% oxygen breathing in different stages of nonproliferative RD. However, a significant reduction could be demonstrated in proliferative DR with this method.

Characterization of the cytochrome P450 enzymes involved in the in vitro metabolism of ethosuximide by human hepatic microsomal enzymes

1. The relative roles of human hepatic cytochrome P450 (CYP) subfamilies participating in ethosuximide metabolism have been studied in vitro using humanized heterologous CYP microsomal systems expressing either CYP1A2, CYP2A6, CYP2C9, CYP2D6, CYP2E1 or CYP3A4. 2. Ethosuximide was incubated with each expression system at 37 degrees C, and its hydroxylated metabolite was quantified by HPLC assay. 3. K(m) and V(max) values for metabolite formation were estimated for CYP3A4 and CYP2E1. The K(m) values for the metabolite formed were 1.40 and 0.24 mM for CYP3A4 and CYP2E1, respectively. The V(max) values were 0.65 and 0.14 nmol mg-1 protein min(-1) for CYP3A4 and CYP2E1, respectively. 4. These parameters could not be measured for other enzymes, since metabolite concentrations formed were below the HPLC detection limits. 5. Immuno-inhibition studies using specific antibodies against CYP3A4 or CYP2E1 revealed that ethosuximide metabolite levels decreased when the amount of added CYP3A4 or CYP2E1 antibody increased, with anti-CYP3A4 antibodies yielding a greater inhibitory effect. 6. Simulations of scaled-up in vivo ethosuximide CL(hepatic) mediated by CYP3A4 and CYP2E1 based on the in vitro CL'(int) values, which were calculated from the foregoing respective V(max) and K(m) values, project that well over 90% of in vivo CL(hepatic) is due to CYP3A4. These results support an important role for CYP3A in human ethosuximide metabolism, and a minor role for CYP2E1.

Nunatak survival of the high Alpine plant Eritrichium nanum (L.) Gaudin in the central Alps during the ice ages

Polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLPs) and sequence analysis of noncoding regions of chloroplast DNA were used to investigate 37 populations of Eritrichium nanum covering its total distribution area, the European Alps. There was no haplotypic variation within the populations, and most haplotypes were restricted to single sites or to neighbouring populations, suggesting low levels of long distance gene flow via seeds. The present geographical distribution of haplotypes probably reflects an ancient geographical pattern within two regions in the intensely glaciated western and eastern central Alps identified as genetic hotspot areas. These two regions contained seven of the total of 11 haplotypes, including many of the most derived ones. The divergent haplotypes formed closely related groups, which supported a separate evolution of these haplotypes in these two regions and, more importantly, gave strong evidence for the in situ survival of these populations on nunataks within the western and eastern central Alps during Pleistocene glaciation. This result is in concordance with a previous study on E. nanum using nuclear markers. Only one haplotype was common and widespread throughout the distributional range of E. nanum. At the same time, it was the evolutionarily basal-most and all other haplotypes were best described as its descendants. This haplotype is hypothesized to be genetically identical to a Tertiary Alpine colonizing ancestor, whose distribution was secondarily fragmented and infiltrated by derived haplotypes originating through local mutations.

AFLP diversity in the common vetch ( Vicia sativa L.) on the world scale

The Vavilov Institute of Plant Industry (VIR) keeps a living seed collection of about 700 accessions of landraces and local cultivars of common vetch ( Vicia sativa L.) that have been collected over a period of more than 50 years throughout the former USSR. Much of the material is available nowhere else. The collection of this economically important fodder crop is well adapted to the various growing regions of Russia and serves as a basis for the all domestic vetch breeding programs. Using AFLP as a DNA fingerprinting method we investigated 673 accessions from the VIR and compared their genetic variability with that of the worldwide vetch collection of the Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK), 450 accessions. The analysis is a first assessment of the intra-specific diversity of V. sativa stored ex situ on a scale of more than 1,000 accessions. Six primer combinations, which gave clear polymorphic amplification products with 96 test samples, were chosen from 111 primer combinations tested. The selected AFLP primers used to analyse the V. sativa intra-specific diversity resulted in 70 unequivocally recognizable polymorphic fragments. We found that all of the AFLP fragments generated can be detected with varying frequency throughout the entire distribution area of V. sativa. The difference in frequency of some AFLP fragments between the regions may amount to 90%. The arrangement of most of the accessions in all dendrograms reflects their geographical origin, with a differentiation between Russia, Western Europe, Turkey and Bulgaria, and the Mediterranean. The "Russian" genepool stored at the IPK is a limited and biased sample of the available diversity when compared to the material stored at the VIR. Approximately 10-15% of the accessions in each geographical group showed AFLP patterns that clustered with members of other groups. This appreciable overlap raises several questions: (1) to which degree is an AFLP pattern representative of the overall genetic similarity of the samples; (2) to which degree are samples collected at a site adaptively limited to that site? Since our data identify accessions with very similar AFLP patterns from very diverse geographic origins, a comparison of the agronomic performance of these accessions (possibly in the two regions) will provide important information for the utilization of ex situ germplasm collections.

Molecular phylogeny of Coelogyne (Epidendroideae; Orchidaceae) based on plastid RFLPS, matK, and nuclear ribosomal ITS sequences: evidence for polyphyly

To evaluate the monophyly of Coelogyne (Epidendroideae; Orchidaceae) and reveal sectional relationships and relations to allied genera in subtribe Coelogyninae, we collected PCR (polymerase chain reaction) amplified restriction fragment length polymorphisms (RFLPs) from 11 plastid regions for 42 taxa (28 Coelogyne species and 14 representatives of other genera) and three outgroups from Bletiinae and Thuniinae. We also sequenced a large portion of the plastid trnK intron (mostly matK) and the nuclear ribosomal DNA internal transcribed spacers ITS1 and ITS2 (including the 5.8S gene). Separate phylogenetic analyses on each data set using maximum parsimony produced mainly congruent (except for the position of Panisea) but weakly supported clades. Parsimony analysis of the combined data clearly identified three main clades in Coelogyninae. Whereas Coelogyninae are monophyletic, Coelogyne is polyphyletic, with species falling into at least two well-supported clades. The utility of morphological characters used in previous classifications was explored by reconstructing character state evolution on one of the four molecular trees. Lip base and petal shape were homoplasious, whereas ovary indumentum and flower number were congruent with well-supported groups. The implications of our results for the classification of Coelogyne are discussed, and a reorganization of the genus by including Neogyna and Pholidota and removing several species is proposed.

[Age-related contractility of retinal arterioles during pure oxygen breathing]

BACKGROUND

Pure oxygen breathing is a non-invasive method to test the contractility of retinal arterioles. The normal response curve of this provocation method was tested using the Retinal Vessel Analyzer (RVA). Statistical analysis between groups was performed with th Man-Whitney test, correlations were tested with Pearsons' linear function.

METHODS

After a 3-min baseline measurement 32 healthy volunteers breathed 100% oxygen for 5 min. The diameter of an retinal arteriole was measured continuously during this provocation by the RVA. Volunteers were separated into four groups according age.

RESULTS

All four groups reacted to pure oxygen breathing with significant vasoconstriction of the retinal arteriole: in the youngest group (20-29 years) the reduction was 14.6 +/- 5.2% and the three older age groups 9.4 +/- 5.2%, 4.6 +/- 2.7%, and 2.8 +/- 3.3%. The correlation between vasoconstriction and age was r = 0.73.

CONCLUSIONS

Pure oxygen breathing is an easily performed method with minimal invasiveness to the patient. However, the age-correlated response curve must be kept in mind for the clinical use of this method.