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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.
Biochemical profiles on API Rapid CH* strips and protein profiles on polyacrylamide gels in the presence of sodium dodecyl sulfate were used to distinguish two strains of the entomopathogenic fungusBeauveria bassiana (Balsamo) Vuillemin, ARSEF 2991 and ATCC 44860. Next, the toxicity of these two strains was determined at concentrations of 102, 104, 106 and 108 blastospores/ml on larvae of the Colorado potato beetleLeptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) and of its predator, the spotted ladybird beetle,Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae). Both strains were highly toxic toL. decemlineata larvae. However, the two strains exhibited different levels of toxicity forC. maculata larvae: ARSEF 2991 was toxic, whereas ATCC 44860 caused little coccinellid larval mortality.
Résumé Les profils biochimiques sur galeries API Rapid CH* et les profils protéiques sur gels de polyacrylamide ont été utilisés pour distinguer deux souches du champignon entomopathogèneBeauveria bassiana (Balsamo) Vuillemin. La toxicité de ces deux souches a été déterminée à des concentrations de 102, 104, 106 et 108 blastospores/ml sur des larves du doryphore,Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) et de la coccinelle maculéeColeomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae). Les deux souches deB. bassiana se sont avérées actives à l'égard des larves deL. decemlineata. Toutefois la souche ARSEF 2991 s'est avérée pathogène pour les larves deC. maculata, alors que la souche ATCC 44860 a provoqué une faible mortalité des larves.
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5.
Immunoglobulins are encoded by a large multigene system that undergoes somatic rearrangement and additional genetic change during the development of immunoglobulin-producing cells. Inducible antibody and antibody-like responses are found in all vertebrates. However, immunoglobulin possessing disulfide-bonded heavy and light chains and domain-type organization has been described only in representatives of the jawed vertebrates. High degrees of nucleotide and predicted amino acid sequence identity are evident when the segmental elements that constitute the immunoglobulin gene loci in phylogenetically divergent vertebrates are compared. However, the organization of gene loci and the manner in which the independent elements recombine (and diversify) vary markedly among different taxa. One striking pattern of gene organization is the "cluster type" that appears to be restricted to the chondrichthyes (cartilaginous fishes) and limits segmental rearrangement to closely linked elements. This type of gene organization is associated with both heavy- and light-chain gene loci. In some cases, the clusters are "joined" or "partially joined" in the germ line, in effect predetermining or partially predetermining, respectively, the encoded specificities (the assumption being that these are expressed) of the individual loci. By relating the sequences of transcribed gene products to their respective germ-line genes, it is evident that, in some cases, joined-type genes are expressed. This raises a question about the existence and/or nature of allelic exclusion in these species. The extensive variation in gene organization found throughout the vertebrate species may relate directly to the role of intersegmental (V<==>D<==>J) distances in the commitment of the individual antibody-producing cell to a particular genetic specificity. Thus, the evolution of this locus, perhaps more so than that of others, may reflect the interrelationships between genetic organization and function.   相似文献   
6.
Chlorogenic (5‐CQA), 1,5‐, 3,5‐, 4,5‐ and 3,4‐dicaffeoylquinic (DCQA) acids were identified and quantified in the methanol extracts of Inula oculus‐christi L., I. bifrons L., I. aschersoniana Janka var. aschersoniana, I. ensifolia L., I. conyza (Griess .) DC. and I. germanica L. by HPLC analysis. The amount of 5‐CQA varied from 5.48 to 28.44 mg/g DE and the highest content was detected in I. ensifolia. 1,5‐DCQA (4.05–55.25 mg/g DE) was the most abundant dicaffeoyl ester of quinic acid followed by 3,5‐DCQA, 4,5‐DCQA and 3,4‐DCQA. The extract of I. ensifolia showed the highest total phenolic content (119.92±0.95 mg GAE/g DE) and exhibited the strongest DPPH radical scavenging activity (69.41±0.55 %). I. bifrons extract was found to be the most active sample against ABTS.+ (TEAC 0.257±0.012 mg/mL) and the best tyrosinase inhibitor. The studied extracts demonstrated a low inhibitory effect towards acetylcholinesterase and possessed low cytotoxicity in concentration range from 10 to 300 μg/mL toward non‐cancer (MDCK II) and cancer (A 549) cells.  相似文献   
7.
Combined methylmalonic aciduria with homocystinuria (cblC type) is a rare disease caused by mutations in the MMACHC gene. MMACHC encodes an enzyme crucial for intracellular vitamin B12 metabolism, leading to the accumulation of toxic metabolites e.g. methylmalonic acid (MMA) and homocysteine (Hcy), and secondary disturbances in folate and one-carbon metabolism when not fully functional. Patients with cblC deficiency often present in the neonatal or early childhood period with a severe multisystem pathology, which comprises a broad spectrum of treatment-resistant ophthalmological phenotypes, including retinal degeneration, impaired vision, and vascular changes. To examine the potential function of MMACHC in the retina and how its loss may impact disease, we performed gene expression studies in human and mouse, which showed that local expression of MMACHC in the retina and retinal pigment epithelium is relatively stable over time. To study whether functional MMACHC is required for retinal function and tissue integrity, we generated a transgenic mouse lacking Mmachc expression in cells of the peripheral retina. Characterization of this mouse revealed accumulation of cblC disease related metabolites, including MMA and the folate-dependent purine synthesis intermediates AICA-riboside and SAICA-riboside in the retina. Nevertheless, fundus appearance, morphology, vasculature, and cellular composition of the retina, as well as ocular function, remained normal in mice up to 6 or 12 months of age. Our data indicates that peripheral retinal neurons do not require intrinsic expression of Mmachc for survival and function and questions whether a local MMACHC deficiency is responsible for the retinal phenotypes in patients.  相似文献   
8.
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   
9.
The amount of sesquiterpene lactones and the lactone profile of Arnica montana L. in flowering and seed formation stages in vitro and in vivo propagated from seeds of German, Ukrainian, and Austrian origin and grown in two experimental fields were studied. It was found that in vitro propagated 2‐year plants in full flowering stage accumulated higher amount of lactones in comparison to in vivo propagated 3‐year plants and to the seed formation stage, respectively. Helenalins predominated in in vivo propagated 2‐year or in vitro propagated 3‐year plants. 2‐Methylbutyrate (2MeBu) was the principal ester in the samples with prevalence of helenalins, while isobutyrate (iBu) was the major one in the samples with predominance of 11,13‐dihydrohelenalins. The results revealed that the environmental conditions on Vitosha Mt. are more suitable for cultivation of Amontana giving higher content of lactones.  相似文献   
10.
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   
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