A DNA oligomer 25 nucleotides long which contained an HMT (4'-hydroxymethyl-4,5', 8-trimethylpsoralen) furan side monoadduct to thymidine at a 5'-TpA-3' site was used as a probe for the polylinker sequence present in single-stranded M13 mp19 DNA and in double-stranded pUC 19 DNA. Hybridization and photofixation were carried out simultaneously in solution under conditions approximating the melting temperature of the probe-target hybrid. Use of probe concentrations greater than 10(-8) M permitted hybridization times of a few minutes. Irradiation with near ultraviolet light converted the HMT monoadduct present in hybrid complexes into an interstrand crosslink. Efficient photofixation removed hybrid from the equilibrium distribution and resulted in the formation of additional probe-target complex. After removal of excess probe by centrifugation through a semi-permeable membrane (Centricon-30), samples were electrophoresed through an alkaline agarose gel which was analyzed by autoradiography. When using an HMT-modified 25-mer probe end-labeled with 3,000 Ci/mmole 32P, 0.015 ng (3.8 X 10(6) copies) of M13 DNA could be detected. With this same probe 10 micrograms of denatured human DNA (corresponding to 3.0 X 10(6) copies) did not give a signal.
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http://dx.doi.org/10.1093/nar/14.24.9943 | DOI Listing |
Clin Res Hepatol Gastroenterol
January 2025
Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India. Electronic address:
Background: Covalently closed circular DNA (cccDNA) is a stable, episomal form of HBV DNA. cccDNA is a true marker for the intrahepatic events in controlled CHB infection. Quantifying cccDNA is critical for monitoring disease progression, and efficacy of anti-viral therapies.
View Article and Find Full Text PDFLancet HIV
January 2025
Fundación IDEAA, Buenos Aires, Argentina.
Background: Dolutegravir plus lamivudine has emerged as a preferred treatment for HIV; however, initiating this regimen without baseline resistance testing raises concerns about the potential presence of pretreatment lamivudine resistance. We aimed to evaluate the efficacy of dolutegravir plus lamivudine in the absence of information on baseline resistance testing in treatment-naive people with HIV.
Methods: We did an open-label, non-inferiority, single-centre, phase 4, randomised controlled study (D2ARLING), designed to assess the efficacy and safety of dolutegravir plus lamivudine in treatment-naive people with HIV with no available baseline resistance testing.
Bioanalysis
January 2025
Bioanalytical Services Department, WuXi AppTec (Shanghai) Co. Ltd, Shanghai, China.
Background: Circulating tumor DNA (ctDNA) is a promising biomarker for cancer prognosis and drug development. A major challenge in the ctDNA determination method is discriminating ctDNA from highly similar but significantly more abundant wild-type DNA sensitively and accurately.
Method: An ultrasensitive qPCR method termed Triple Enrichment Amplification of Mutation PCR (TEAM-PCR) was developed to detect EGFR T790M mutation.
BMJ Open
December 2024
Shanghai Shuguang Hospital Affiliated with Shanghai University of TCM, Shanghai, Shanghai, China
Introduction: Health education, weight control and exercise therapy are recognised treatment options for the non-surgical management of knee osteoarthritis (KOA); however, the pain and muscle fatigue associated with exercise make it difficult for patients to initially adhere. Traditional Chinese medicine (TCM) massage is an important complementary and alternative therapy that can effectively address these deficiencies. According to TCM theory and preliminary clinical practice, loosening of the muscles while pointing to acupoints can promote the recovery of KOA.
View Article and Find Full Text PDFJ Microorg Control
January 2025
Division of Microbiology, National Institute of Health Sciences.
Bovine coronavirus (BCoV), a significant cattle pathogen causing enteric and respiratory diseases, is primarily detected using reverse transcription-polymerase chain reaction. Our objective was to develop a novel detection method for BCoV by matrix-assisted laser desorption/ionization‒time-of-flight mass spectrometry (MALDI-TOF MS). Peptide mass fingerprint analysis revealed that nucleocapsid (N), membrane (M), and hemagglutinin-esterase (HE) were three main BCoV proteins.
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