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1.
We report on a unified rapid betaine-based-PCR protocol for amplification of the (CAG)n region in Huntington disease (HD) and the (CGG)n region in Fragile X syndrome (FXS), followed by an electrophoretic separation on automated sequencer for precise determination of the triplet numbers. The high betaine concentration (2.5 M betaine) permits precise amplification of the CAG and CGG repeats. Ten HD affected patients and 10 healthy individuals from HD families were re-evaluated. For FXS the CGG region in normal individuals and premutations of about 100 repeats were precisely amplified by this protocol. Ten unrelated FXS premutation carriers and 24 mentally retarded non-FXS affected boys were re-examined by this method. The results totally coincided with the previous ones. This protocol is a good choice as a fast screening test. Within 24 h we can have preliminary information on the patient’s genetic status. Normal individuals, CGG premutation carriers up to 100 repeats, as well as HD patients carrying an expansion up to 50 CAG repeats can be easily clarified. This accounts for a relatively large proportion (about 90%) of the suspected HD and FXS patients, referred to our laboratory for genetic analysis. The calculation of the repeat’s number is more accurate for the correct interpretation of the results, screening tests and genetic counselling.  相似文献   
2.
Abstract: The effect of timing of application on the incompatibility of three fungicides (metalaxyl, mancozeb, copper oxide) and isolate MK2001 of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin was assessed in vitro . Isolate MK 2001 at 1 × 107 conidia/ml concentration was highly pathogenous to adults of Lygus lineolaris (Hemiptera) (84% mortality at day 4 post-treatment). The fungicides at the manufacturer recommended rate (1X) were strongly fungistatic and inhibited the fungal isolate radial growth on Sabouraud dextrose agar (SDA). Mancozeb, metalaxyl and copper oxide exhibited insecticidal activity of 24, 40 and 48% respectively, on L. lineolaris adults. It is clear that application of the fungal isolate MK2001 2–4 days before applying fungicides metalaxyl, mancozeb or copper oxide synergized the insecticidal effect of the isolate. On the contrary, application of metalaxyl, mancozeb, copper oxide 2–4 days before applying isolate MK2001 antagonized the insecticidal effect. The simultaneous use of each fungicide (metalaxyl, mancozeb or copper oxide) and the isolate gave lesser insect mortality. This study revealed that although some fungicides are incompatible for use alongside fungal isolates, the proper evaluation of their time of use could be beneficial in biological control or IPM programmes. Furthermore, the application of B. bassiana isolate MK2001 followed by fungicide application could synergize insecticidal activity.  相似文献   
3.
A population of Chironomus riparius from a Po river station near Moncalieri (a trace-metal polluted station) was studied. In this population was established a great variability of band structure of polytene chromosomes as well as paracentric heterozygous inversions, deletions, deficiencies, partial breaks, diploid chromosome fragments, and changes in functional activity and appearance of heterochromatin. In arms A through F, some bands had an increased size compared to the standard chromosomic map. Some bands appeared in a heterozygous or normal homozygous state or were amplified. In all arms, many condensed stable bands appeared in the decondensed state when compared to the standard map. Asynaptic zones in arms E and G as well as heterozygous Balbiani rings and NORs were established. Very often the 4th chromosome was almost completely heteropycnotic and looded like a pompon chromosome. For the first time in this species, a high frequency of ectopic pairings of different arms was observed. Telomeric regions involved in ectopic pairings had a granular appearance, as did some centromeres. The hypothesis is advanced that such a high frequency of structural rearrangements could be correlated with genomic distribution of specific mobile elements.  相似文献   
4.
The essential‐oil composition of six native populations of Sideritis scardica from Bulgaria was studied by GC‐FID and GC/MS analyses. Altogether, 37 components, representing 73.1 to 79.2% of the total oil content were identified. Among them, α‐pinene (4.4–25.1%), β‐pinene (2.8–18.0%), oct‐1‐en‐3‐ol (2.3–8.0%), phenylacetaldehyde (0.5–9.5%), β‐bisabolene (1.3–11.0%), benzyl benzoate (1.1–14.3%), and m‐camphorene ( 1 ; 0.3–12.4%) were the main compounds. All samples were characterized by low contents of oxygenated mono‐ and sesquiterpenes (≤1.6 and 2.3%, resp.). Principal component analysis (PCA) and cluster analysis (CA) showed a significant variability in the chemical composition of the studied samples as well as a correlation between the oil profiles and the ecological conditions of the natural habitats of S. scardica.  相似文献   
5.
The proliferative inflammatory atrophy (PIA) is considered as a possible precursor of prostate intraepithelial neoplasia (PIN) or prostate cancer (PCa). In this study we assessed quantitatively the expression of AMACR, p63, COX-2, GST and iNOS in serial paraffin-embedded tissue sections obtained after radical prostatectomy of PCa patients (n = 30). The applicability of these markers to distinguish PIA, PIN and PCa was evaluated. We also compared the immunohistochemical expression profiles of AMACR, COX-2 and GST in the luminal and basal cells in lesions of PIN arisen in PIA or PIA alone. Two different patterns of COX-2 expression according to the p63 status of the basal cells were found. This observation gives us grounds to hypothesize that the diverse COX-2 patterns resulted from an initial basal cell damage which subsequently propagated to its luminal secretory cells progeny.  相似文献   
6.
The influence of copper (II) ions on the growth, accumulation properties and superoxide dismutase (SOD) activity of a growing culture of Aspergillus niger B-77 were studied. Microbial growth, the level of copper (II) accumulation and SOD activity depended on the initial copper (II) concentration. Aspergillus niger is able to accumulate large amounts of copper (II) from the nutrient medium with 200 mg x l(-1) copper (II) ions without loosing its biological activities. Addition of copper (II) ions increased the SOD activity in the growing cell cultures. The changes in enzyme activity induced by heavy metal ions might be used as an indicator of intracellular oxy-intermediate generation in a cell culture growing under stress conditions.  相似文献   
7.
Aerial parts of Achillea collina afforded, in addition to five known sesquiterpene lactones two new germacranolides and one new eudesmanolide, the structures of which were elucidated by spectroscopic methods.  相似文献   
8.
The lactone profile of six origins of Achillea collina growing in Bulgaria was studied and significant variability was observed. The reasons for the differences in the lactone composition are discussed. Twenty-five components in total were isolated and identified, while the presence of ten lactones was proved by intensive TLC analysis in comparison with reference compounds. The structures of the components 17, 20, 25-30 were established by spectroscopic methods. The structure of 7, a cyclization product of 6, was also discussed. The anti-inflammatory activity of some extracts, fractions and individual compounds was tested in vitro by determining the inhibitory effects on induced human neutrophils.  相似文献   
9.
The flower heads of Achillea distans afforded nine new sesquiterpene lactones (one glaucolide, six guaianolides and two dimeric lactones) in addition to 18 known terpenoids. The structures and stereochemistry of the new compounds were elucidated by spectroscopic methods. The stereochemistry of 11,13-dihydroezomontanin was revised.  相似文献   
10.
Amino Acids - The Alzheimer’s disease leads to neurodegenerative processes and affecting negatively million people worldwide. The treatment of the disease is still difficult and incomplete in...  相似文献   
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