Effects of resistance training on central blood pressure in obese young men.

Central blood pressure is a predictor of the risk of cardiovascular disease (CVD), and the effects of resistance training (RT) on central blood pressure are largely unknown. This study explored the effects of high-intensity RT on central blood pressure, indices of arterial stiffness and wave reflection and inflammatory/atherogenic markers in overweight or obese, sedentary young men. Thirty-six participants were randomized to RT (12 weeks of training, 3/wk, n=28) or control groups (C, 12 weeks of no training, n=8) and assessed for changes in central and brachial blood pressures, augmentation index (AIx), carotid-femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), body composition, lipids and inflammatory/atherogenic markers. High-intensity RT resulted in decreased central and brachial systolic/diastolic blood pressures (all P0.03), despite not altering AIx (P=0.34) or cfPWV (P=0.43). The vascular endothelial growth factor increased (P=0.03) after RT, without any change in cIMT, C-reactive protein, oxidized LDL (oxLDL) or other inflammatory markers (all P0.1). Changes in the central systolic blood pressure (cSBP) were positively correlated with changes in oxLDL (r=0.42, P=0.03) and soluble E-selectin (r=0.41, P=0.04). In overweight/obese young men, high-intensity RT decreases cSBP, independently of weight loss and changes in arterial stiffness. The cardioprotective effects of RT may be related to effects on central blood pressure.

Agrobacterium T-DNA mutation causes the loss of GUS expression in transgenic tobacco.

A new freezer stock of an Agrobacterium tumefaciens clone of LBA4404/pBI121, designated 8999, was found to contain a mutation in the T-DNA region. GUS activity in Agrobacterium 8999 was reduced to levels in negative controls of LBA4404. Additionally, GUS activity in T1 seedlings from tobacco plants transformed with 8999 was reduced to that of untransformed plants. Southern and northern blotting showed that Agrobacterium clone 8999 transferred its T-DNA into the plant, that the correct sizes of 35S promoter and GUS coding region were integrated into the plant's genome in the correct orientation, but that no transcript was detectable after 24 h. Genomic DNA from a T1 seedling from 8999 transformation, digested with HpaII and MspI, indicated no methylation in the promoter region. We conclude from this data that Agrobacterium 8999 has a stable mutation that reduces expression at the mRNA level and is responsible for the lack of GUS expression in plants transformed with this Agrobacterium clone. Therefore, unselected genes within the T-DNA region may suffer mutations in Agrobacterium.