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Nucleotide composition of both growth hormone variants of rainbow trout (Oncorhynchus mykiss) has been strongly preserved evolutionally what might suggest that any change within these sequences can have an influence on the functioning of the somatotropic axis. A 121 bp fragment that contained nearly the entire B intron was amplified by the polymerase chain reaction. PCR products were bidirectionally sequenced. PCR products were digested by TaiI according to manufacturer’s instructions and resulting DNA was subjected to electrophoresis. An analysis of the gene fragment for growth hormone 2 showed the presence of SNP, easily identifiable by means of digestion with TaiI restriction enzyme. Statistical analysis confirmed that homozygous GHBB fish were the longest (31.77 cm) and the heaviest (404.70 g) and were statistically significantly different (P ≤ 0.05) from heterozygous GHAB fish. Mean length of GHAA homozygous fish was insignificantly lower (30.06 cm) with mean body weight of 339.12 g than homozygotes GHBB.
Genetic variability of three sympatric crucian carp ( Carassius carassius ) populations from NW Poland was studied within a research project aimed at assessing the utility of those populations for stocking in inland waters. DNA samples were collected from 65 individuals. Restriction analysis was performed using 4 enzymes (HaeIII, HinfI, FspBI, TasI) of known restriction sites. The restriction pro files obtained were classified as belonging to a single haplotype (H-1). Selected DNA products were sequenced; the subsequent comparison made it possible to detect the presence of substi- tutions in the genome fragment analysed.
Thrips from the genus Frankliniella (Thysanoptera, Thripidae) are phytophagous on crops and wild plants. Some of them cause slight economic damage, however, others including F. occidentalis and F. intonsa are responsible for considerable losses in crop production. Moreover, they constitute a double threat for host plants by not only feeding on them but also vectoring viruses, some of which are on the quarantined list of the European Plant Protection Organization. The rapid detection and differentiation between more and less harmful Frankliniella species is, therefore, important in order to combat the pests at the time of their appearance. In this study, we have undertaken to develop a method of detecting F. occidentalis, F. intonsa, F. pallida, and F. tenuicornis. The protocol is based on PCR amplification of ITS1 rDNA fragments of these insects using universal primers pair giving products of slightly distinct length for studied insects. Restriction enzymes digestion which is easy to interpret, allows for visible differentiation of all these Frankliniella species. The method was shown to be species-specific and sensitive. Even single specimens in either the larvae or adult stage could be distinguished.
The aim of this study was molecular identification of S. aureus strains isolated from mastitic milk samples and establishing the genetic relationship between strains isolated from cows belonging to the same herd. In all 43 isolated strains the gap gene (930 bp) was amplified, which enabled their affiliation to the Staphylococcus genus to be established. PCR-RFLP with AluI endonuclease of the gap gene as well as nuc (450 bp) and coa (1130 bp) gene amplification allowed precise S. aureus species identification. One hundred percent of the genetic relationship between strains was established via RAPD-PCR and coa-typing.
Bacterial speck of tomato caused by Pseudomonas syringae pv. tomato appeared to be recently the most important disease on tomato in Poland. The genetic relationships among four Polish strains of race 0 P. syringae pv. tomato of different origin, isolated from tomato plants, were examined by RAPD and PCR-RFLP techniques. Amplification of bacterial DNA using 33 primers with RAPD technique showed, that similarity of strains expressed by the Nei-Li coefficient was very high (above 0.8). Next, the restriction analysis of amplified region ITS with the use of 5 endonucleases revealed, that profiles obtained from electrophoretic separation of DNA fragments were also very similar. On the basis of those analyses it was concluded that all strains tested constituted a closely related group. However, they showed various level of virulence as was demonstrated on the inoculated leaves of tomato plants growing in the greenhouse.
PCR-RFLP and nucleotide sequencing based genotyping of Toxoplasma gondii Indian isolates (Izatnagar and Chennai isolates and Chennai clone) vis-a vis RH-IVRI strain was conducted by targeting GRA6 as genetic marker. The 791 bp GRA6 product was PCR amplified from the genomic DNA of different T. gondii Indian isolates, including the RH-IVRI strain. Tru1I restriction endonuclease based PCR-RFLP of GRA6 sequence produced polymorphic digestion pattern that discriminated the virulent RH-IVRI strain (as type I) from the moderately virulent local isolates as type III. The PCR amplicon of T. gondii GRA6 from RH-IVRI strain as well as from the local isolates were cloned in cloning vector and custom sequenced. The nucleotide and deduced amino acid sequences of T. gondii isolates were aligned with that of the type I, II and III strains (RH, BEVERLEY, ME49, C56, TONT and NED) available in public domain and analyzed in silico using MEGA version 4.0 software. Nucleotide sequencing and phylogenetic analysis of GRA6 marker from the Indian isolates revealed a close genetic relationship with type III strains of T. gondii. Further, detection of a single nucleotide polymorphism (SNP) at positions 162 and 171 of the GRA6 marker, established the lineage of Indian isolates as type III. This is the first report on characterization of T. gondii lineage as type III in selective chicken population of India based on PCR-RFLP and sequence analysis of GRA6 gene.
A total of seventeen isolates of Aspergillus flavus from maize were collected from different agro-ecological zones of Tamil Nadu, India. The isolates were tested for their ability to produce aflatoxin B1 (AFB1) in vitro by indirect competitive enzyme-linked immunosorbent assay (ELISA). The amount of AFB1 produced by the isolates of A. flavus ranged from 1.9 to 206.6 ng/ml. Among the various isolates of A. flavus, the isolate AFM46 produced the highest amount of AFB1. DNA was extracted from A. flavus isolates and their molecular variability was investigated by using restriction fragment length polymorphism (RFLP) analysis of the PCR-amplified internal transcribed spacer (ITS) regions of ribosomal DNA. PCR amplification with ITS1 and ITS4 primers resulted in the amplification of a product of approximately 600 bp. Digestion of the PCR products with the restriction enzymes EcoRI, HaeIII and TaqI produced fragments of different sizes. Analysis of the genetic coefficient matrix derived from the scores of RFLP profiles showed that minimum and maximum per cent similarities among the tested A. flavus strains ranged from 0 to 88%. Cluster analysis using the unweighted pair-group method with arithmetic average (UPGMA) clearly separated the isolates into five groups (group I–V) confirming the genetic diversity among the A. flavus isolates from maize.
In the times of industrial food production, regional and traditional food articles provide an attractive alternative for people looking for unforgettable sensory impressions. Regional or traditional food, commonly recognized as palatable and healthy, is also, for many consumers, a unique, sentimental journey back to tastes from childhood times. A gradual increase of demand for this type of food articles as well as relatively high prices of these products may generate among unscrupulous food manufacturers a number of improper production practices, e.g. replacement of a more expensive meat by a less expensive alternative. Species composition of meat products can be verified using chromatographic, immunological, electrophoretic, or genetic methods. One of the genetic methods applied in examining the authenticity of food composition, including meat and its products, is the polymerase chain reaction (PCR). This paper presents the most important techniques utilizing this technology to identify the origin of specific meat components constituting part of regional or traditional food articles. It was demonstrated that PCR techniques, in combination with species-specific primers, PCR-RFLP, PCR-SSCP and real-time PCR, allow identification of meat species occurring in-dependently or in mixtures with other meat species as well as meat subjected to thermal treatment or other technological processes in the course of industrial production. The only exception is the PCR-RAPD method that fails to identify meat species in the case of strong DNA degradation or in complex meat mixtures
W latach 1998-2005 prowadzono obserwacje i badania nad występowaniem fitoplazm w drzewach i krzewach ozdobnych w Polsce. Przedmiotem badań były krzewy z rodzaju Clematis sp., Magnolia spp. i Rosa sp. oraz drzewa z rodzaju Acer sp., Carpinus sp., Fagus sp., Fraxinus sp. i Quercus spp. wykazujące objawy chorobowe sugerujące porażenie przez fitoplazmy. Objawy te obejmowały zahamowanie wzrostu, zmiany w zabarwieniu a nawet nekrozę i deformację liści, proliferację i zamieranie pędów, czasem deformację i zielenienie lub brak kwiatów oraz zamieranie roślin. Do wykrywania i identyfikacji fitoplazm stosowano test biologiczny oparty na reakcji rośliny testowej Catharanthus roseus, zakażanej techniką szczepienia, oraz analizę PCR-RFLP. Stosując technikę szczepienia, fitoplazmy przeniesiono z chorych róży, magnolii i klonu na siewki C. roseus. Przy pomocy techniki łańcuchowej reakcji polimerazy (PCR) ze starterami amplifikującymi fragment 16Sr DNA fitoplazm, obecność fitoplazmatycznego DNA wykryto w roślinach Rosa spp., Magnolia spp., Clematis sp., Fraxinus excelsior, Carpinus sp. i Acer negundo oraz w eksperymentalnie zakażonych siewkach C. roseus. Analiza RFLP produktu amplifikacji z użyciem enzymów restrykcyjnych AluI, HhaII MseI i RsaI wykazała, że rośliny grabu, jesionu, klonu, magnolii, powojnika i róży były naturalnie porażone przez fitoplazmę z grupy żółtaczki astra (16SrI-B) - 'Ca. Phytoplasma asteris’. W niektórych roślinach róży i magnolii stwierdzono także fitoplazmę z grupy proliferacji jabłoni (16SrX-A) - ‘Ca. Phytoplasma mali’. W badanych roślinach fitoplazmy występowały nierównomiernie i w stosunkowo niskiej koncentracji, przez co mogły być wykrywalne dopiero w drugiej rundzie PCR. W roślinach buka i dębu, mimo wyraźnych symptomów, nie wykryto obecności fitoplazmatycznego DNA.
Bazując na łańcuchowej reakcji polimerazy (PCR), opracowano wiele tech­nik, które są stosowane w kryminalistyce, medycynie, badaniach filogenetycznych oraz do identyfikacji i różnicowania organizmów. Wybór metody do rutynowego stosowania w danym laboratorium nie jest prosty i wymaga zaznajomienia się z wieloma technikami. Chcąc ułatwić wybór metody do analizy drobnoustrojów, w pracy zamieszczono opis i po­równanie następujących technik: RAPD (Randomly Amplified Polymorphic DNA), PCR- RFLP (PCR-Restriction Fragments Length Polymorphism), RISA (Ribosomal Intergenic Spacer Analysis), AFLP (Amplified Fragment Length Polymorphism), Multiplex PCR oraz Real-time PCR. Metody porównano pod względem cech najbardziej użytecznych, jakimi są: zakres stosowania technik, powtarzalność analiz, trudność w wykonaniu oznaczeń, cza­sochłonność, możliwości automatyzacji badań oraz koszty jednostkowej analizy.
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