scholarly journals Molecular Screening for P-Element Insertions in a Large Genomic Region of Drosophila melanogaster Using Polymerase Chain Reaction Mediated by the Vectorette

Genetics ◽  
1998 ◽  
Vol 149 (3) ◽  
pp. 1427-1434 ◽  
Author(s):  
Harald Eggert ◽  
Kirstin Bergemann ◽  
Harald Saumweber

Abstract As an alternative to existing methods for the detection of new insertions during a transposon mutagenesis, we adapted the method of vectorette ligation to genomic restriction fragments followed by PCR to obtain genomic sequences flanking the transposon. By combining flies containing a defined genomic transposon with an excess of flies containing unrelated insertion sites, we demonstrate the specificity and sensitivity of the procedure in the detection of integration events. This method was applied in a transposon-tagging screen for BJ1, the Drosophila homolog of the vertebrate gene Regulator of Chromosome Condensation (RCCI). Genetic mobilization of a single genomic P element was used to generate preferentially new local insertions from which integrations into a genomic region surrounding the BJ1 gene were screened. Flies harboring new insertions were phenotypically selected on the basis of the zeste1-dependent transvection of white. We detected a single transposition to a 13-kb region close to the BJ1 gene among 6650 progeny that were analyzed. Southern analysis of the homozygous line confirmed the integration 3 kb downstream of BJ1.

Author(s):  
María Fernanda Calderón Hernádez ◽  

Background: The main objective of this research is to learn the symptoms that occur in this pathology, since we are currently still fighting COVID-19, because of this, it is important to keep us informed about the different diagnostic methods available, which help us reach an earlier and more effective diagnosis. Various articles have been compiled to identify as soon as possible the active cases and thus reduce the number of infections. Materials and methods: This research was conducted on the basis of scientific articles and books, related to COVID-19. Methods: This research was conducted based on 15 scientific articles and 3 books, related to COVID-19. Results: The most important risk factors are diabetes mellitus, hypertension, obesity, age and sex. The most common symptoms in Latin America are dry cough, fatigue, sore throat, and fever. The preferred diagnostic test for COVID-19 is the polymerase chain reaction for its specificity and sensitivity Conclusions: As a conclusion, the main objective of the research was achieved, which is to inform the reader about the most relevant symptoms of SARS-CoV-2 in order to improve the identification of suspected cases. Furthermore, we compare various diagnostic methods that exist to date and determine that PCR is the most specific and sensitive.


2021 ◽  
pp. 2878-2882
Author(s):  
Sirikanda Thanasuwan ◽  
Anupong Tankrathok

Background and Aim: Fasciola spp. are important foodborne trematodes and waterborne zoonotic parasites that cause health problems and economic losses worldwide, including in Thailand. Fasciola spp. are usually detected by sedimentation or the formalin-ethyl acetate concentration technique (FECT) under microscopy, which is less specific and sensitive. Accurate detection is important to detect real incidence for protection against and elimination of fasciolosis in the area. This study aimed to determine the distribution of Fasciola spp. and compare the specificity and sensitivity of FECT under microscopy to that of polymerase chain reaction (PCR) in cattle feces. Materials and Methods: The study was conducted in Kalasin Province, Thailand. Feces of 46 cattle were investigated for infection with Fasciola spp. To detect infection, FECT under microscopy and PCR amplification of the 28S rRNA gene of Fasciola spp. were used to identify egg parasites. Results: Feces of 16 of 46 (34.78%) cattle were positive for Fasciola spp. using FECT under microscopy, whereas PCR showed that 67.39% (31 of 46) were positive for Fasciola spp. False-negative results were as high as 32.61% when diagnosed under microscopy. Conclusion: This study confirmed the infection of cattle with Fasciola spp. in Kalasin Province, indicating that PCR demonstrated higher sensitivity and specificity when diagnosing infection. FECT under microscopy can still be used as a primary and traditional method for diagnosis. However, relapse cases of Fasciola spp. and Paramphistomum spp. should be diagnosed by microscopy combined with PCR. This is the first report on the molecular distribution of fecal samples in cattle in Kalasin Province.


2011 ◽  
Vol 1 (1) ◽  
pp. 45
Author(s):  
Muktiningsih Nurjayadi ◽  
Fera Kurnia Dewi ◽  
Dahlia Dahlia ◽  
S, Restu.N S ◽  
Fitri W

Salmonella typhi is bacteria that cause typhoid disease in humans. In Indonesia, the morbidity number of typhoid disease tends to be increase. Thus, it has been requiring the alternative for handling or preventing that disease. Recently, the detection method commonly uses for S. typhi detection is Serological test. The weakness of this method is often producing less accurate and not specific detection. The previous research was successfully discovered S. typhi gene that codes protein which is contributed at adherents or colonization those bacteria in epithelial human cell. That result was base to develop detection on S. typhi method by Polymerase chain reaction (PCR). The aim of this research is developing a specific and accurate detection method for S. typhi bacteria by PCR. The research result is performed successfully to amplify the fimbrial-C S. typhi gene using pairs of primer FW-INT 2- REV-1A NEW which was designed and synthesized in previous step. That success showed by the finding of the DNA fragment of 0.2 kilobase (kb) proffers to size of DNA fragment which is hopefully in using S. typhi genome as a template. Specificity and sensitivity test for those primers are still conducting to reproducibility results. Base on the results can be concluded that the research have successfully conducted in developing S. typhi detection method using pairs of S. typhi fimbrial-C primer. Hopefully, the studied of developing detection methods was conducted better compare with former detection methods.Keywords: S. typhi detection method, fim-C S. typhi gene, PCRAbstrakSalmonella typhi merupakan bakteri penyebab penyakit tifus pada manusia. Di Indonesia, angka morbiditas penderita penyakit typhus cenderung meningkat, sehingga diperlukan suatu alternatif untuk penanganan atau pencegahan penyakit tersebut. Sampai saat ini metode deteksi S. typhi yang banyak digunakan adalah uji serologi. Kelemahan metode ini adalah sering menghasilkan deteksi yang kurang akurat dan tidak spesifik. Pada penelitian yang dilakukan sebelumnya, telah berhasil ditemukan gen fimbrial-C S. typhi pengkode protein yang berperan dalam penempelan S. typhi pada usus manusia, hasil ini dijadikan landasan untuk pengembangan metode deteksi menggunakan teknik PCR. Tujuan penelitian ini mengembangkan metode deteksi yang akurat dan spesifik untuk bakteri penyebab penyakit typhus pada manusia. Hasil penelitian menunjukkan bahwa telah berhasil dilakukan amplifikasi gen fimbrial-C S. typhi menggunakan pasangan primer hasil perancangan yaitu FW-INT 2- REV-1A NEW. Keberhasilan tersebut ditunjukkan dengan diperolehnya pita DNA berukuran 0.2 kilo basa (kb) sesuai dengan ukuran pita DNA yang diharapkan dengan menggunakan template DNA genom bakteri S. typhi. Uji sensitivitas dan spesifisitas terhadap primer hasil rancangan sedang di kaji lebih lanjut untuk memperoleh reprodusibiltas hasil pengujian. Berdasarkan hasil yang diperoleh dapat disimpulkan bahwa telah berhasil dilakukan pengembangan metode deteksi S. typhi menggunakan pasangan primer fimbrial-C S. typhi. Pengkajian pengembangan metode deteksi yang dihasilkan ini diharapkan dapat lebih baik dibanding beberapa metode deteksi yang sudah ada.Kata Kunci: Metode Deteksi Bakteri typhus, fim-C S. typhi, PCR


1995 ◽  
Vol 308 (2) ◽  
pp. 513-519 ◽  
Author(s):  
M Passadore ◽  
N Bianchi ◽  
G Feriotto ◽  
C Mischiati ◽  
P Giacomini ◽  
...  

In this report we analyse the effects of distamycin and five distamycin analogues on amplification by polymerase-chain reaction (PCR) of two gene sequences displaying a different A+T/G+C content. The first was a 5′ region of the human oestrogen receptor (ER) gene, containing a (TA)26 stretch; the second was a CG-rich sequence of the human Ha-ras oncogene. The results obtained unequivocally demonstrate that the addition of one pyrrole ring significantly improves the ability of distamycin derivatives to interfere with PCR-mediated amplification of the human ER genomic region carrying a (TA)26 stretch. The distamycin analogues analysed differ in the number of pyrrole rings and in the presence of an N-formyl, an N-formimidoyl or a retroamide group at position X1. Among compounds carrying the same number of pyrrole rings, those carrying an N-formyl or an N-formimidoyl group retain a similar inhibitory activity. The retroamide analogues, on the contrary, are much less efficient in inhibiting PCR-mediated amplification of the 5′ER region. With respect to sequence selectivity both distamycin and distamycin analogues exhibit a sequence preference, since they do not inhibit PCR amplification of Ha-ras CG-rich gene regions, with the exception of a distamycin analogue carrying four pyrrole rings.


2016 ◽  
Vol 67 (5) ◽  
pp. 541 ◽  
Author(s):  
Na Li ◽  
Jin Long Yin ◽  
Cui Li ◽  
Da Gang Wang ◽  
Yong Qing Yang ◽  
...  

Soybean mosaic virus (SMV) causes one of the most destructive viral diseases in soybean (Glycine max). The soybean cultivar Dabaima carries the Rsc4 gene for SMV resistance. The genomic region containing Rsc4 was previously localised within a 100-kb region on chromosome 14. The corresponding region contains three complete nucleotide-binding site (NB) and leucine-rich repeat (LRR) type genes and one incomplete gene that is likely non-functional. Quantitative real-time polymerase chain reaction analysis revealed that three candidate genes encoding NB-LRR proteins were differentially expressed in resistant and susceptible lines when the plants were inoculated with SMV strain SC4. To test the involvement of the three candidate genes in Rsc4 mediated resistance, the three genes were silenced using a Bean pod mottle virus (BPMV)-based vector construct. Silencing of three candidate genes attenuated the Rsc4-mediated resistance and induced SMV symptoms in Dabaima plants. Moreover, Rsc4 candidate genes were 78% downregulated when compared with the empty BPMV vector-treated plants. From these results, we concluded that at least one of the three candidate genes encoding NB-LRR proteins is required for Rsc4 resistance to SMV.


Med Phoenix ◽  
2017 ◽  
Vol 1 (1) ◽  
pp. 41-43
Author(s):  
Ravi Shankar Gupta ◽  
Tarannum Khatun ◽  
Akhtar Alam Ansari ◽  
Amrullah Shidiki ◽  
Dipak Bhargava ◽  
...  

Extrapulmonary Tuberculosis is high, challenging the clinicians to make correct diagnosis. Microscopy, culture and fine needle aspiration cytology have their limitations in regard to specificity and sensitivity. In this report, polymerase chain reaction is used for detecting and distinguishing Extrapulmonary Tuberculosis. A case of retropharyngeal abscess was selected from which pus was collected which was negative for microscopy and culture in routine microbiology as well as mycobacteriology. Cytopathological examination was also negative. Polymerase chain reaction was applied to detect Mycobacterium tuberculosis specific IS6110 gene. The patients responded with anti-tuberculosis treatment well. Polymerase chain reaction was introduced for diagnosis of Extrapulmonary Tuberculosis since it can be done within hours, monitor therapy and also differentiate Mycobacterium tuberculosis from other Mycobacterial species.MED Phoenix Volume (1), Issue (1) July 2016, page: 41-43


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