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PubMed1998

[Typing of DNA using the primer extension preamplification (PEP) method--studies of reliability of typing and detection limits].

Primer extension preamplification (PEP), which can amplify sequence-independently a limited quantity of DNA as a whole, allows multiple DNA analyses by polymerase chain reaction (PCR). This technique may be applicable to forensic cases, especially in cases where only small amounts of DNA are available. To define the accuracy and sensitivity of PEP, the DNA typing results of nine loci (TH01, MCT118, HLA-DQ alpha, amelogenin, LDLR, GYPA, HBGG, D7S8, GC) by PCR with PEP (PEP-PCR) were compared with those by PCR without PEP. Both results were identical to each other for each sample tested. Furthermore, amplification of an initial genomic DNA by PEP was found to range from 15 to 600 times of the initial quantity and the efficiency of PEP may depend on the sequences flanking the loci tested. These results indicate that PEP can increase typing potential of PCR from forensic samples.

DNA↗
PubMed2002

Oral flavonoids, chromocarb diethylamine salt and cyaninosides chloride, to eliminate lipoperoxidation postvitrectomy.

This study was undertaken to determine the concentration of malondialdehyde, an end product of lipoperoxidation, in lens and retinal tissue postvitrectomy associated with oral administration of antioxidant flavonoids cyaninosides chloride and chromocarb diethylamine salt or N -acetylcysteine. Fifty adult pigmented rabbits were divided into five groups: (1) controls (normal eyes, malondialdehyde concentration in lens and retina); (2) vitrectomy with BSS Plus (malondialdehyde level measured 2hr after vitrectomy); (3) vitrectomy with BSS Plus and pretreatment with oral cyaninosides chloride 100mg kg day(-1)for 3 weeks (malondialdehyde level measured 2hr after surgery); (4) vitrectomy with BSS Plus and pretreatment with oral chromocarb diethylamine salt 100 mg kg day(-1)for 3 weeks (malondialdehyde level measured 2hr after surgery); and (5) vitrectomy with BSS Plus and pretreatment with oral N -acetylcysteine 200 mg kg day(-1)for 3 weeks (malondialdehyde level measured 2hr after surgery). Lens and retina samples were used to determine malondialdehyde levels using ion-pairing high performance liquid chromatography. Statistical analysis was done using analysis of variance (P<0.05). The content of malondialdehyde in the normal lens was 0.036 +/- 0.017 microg g(-1); in the vitrectomized groups the malondialdehyde concentrations were as follows: (2) 0.027 +/- 0.013 microg g(-1); (3) under detection limit (detection limit=1.75x e-3 microg g(-1)); (4) under detection limit; and (5) 0.020 +/- 0.006 microg g(-1). The results showed that the malondialdehyde concentration in the normal retina was 1.160 +/- 0.361 microg g(-1), while in the vitrectomized groups with or without pretreatment (cyaninosides chloride, chromocarb diethylamine salt, and N -acetylcysteine) the malondialdehyde levels were 2.091 +/- 0.982 microg g(-1), 0.069 +/- 0.024 microg g(-1), 0.082 +/- 0.027 microg g(-1), and 0.215 +/- 0.134 microg/g(-1), respectively, all significantly different from the normal eyes (P<0.05). Vitrectomy induced increased malondialdehyde levels in the retina. Oral flavonoids are an effective protective therapy for surgically induced lipoperoxidation, especially in the retina.

Administration, Oral↗
PubMed2003

The reduction of limits of detection in in vivo counting of low-energy photon emitters by optimising the shape and size of detectors.

This paper compares three ways to reduce the detection limits of in vivo measurements by using passive techniques: the use of shielded rooms, the use of underground laboratories and the adjustment of the detector's dimensions to the examined energy. This study indicates that the efficiency of the detector is not the critical parameter for achieving sensitive measurements in the low-energy range and is secondary to optimisation of the background level. However, reduction of the background has a limited impact on the sensitivity of counting due to 40K in the body. This study also shows that the advantage of using deep underground laboratories could be replaced by detectors with properly designed shape and size and used at ground level in normally shielded rooms to reach the necessary limits of detection for in vivo assessment of low-energy photon emitters.

Artifacts↗