PubMed Health⌕ Search

Biomedical subjects

M H Murphy

Publications and source records attributed to M H Murphy.

8 recordsLinked to original sources
PubMed1998

Training effects of short and long bouts of brisk walking in sedentary women.

This study compared the effects of short and long bouts of brisk walking in sedentary women. Forty seven women aged 44.4 +/- 6.2 yr (mean +/- SD) were randomly assigned to either three 10-min walks per day (short bouts), one 30-min walk per day (long bouts) or no training (control). Brisk walking was done on 5 d x wk(-1), at 70 to 80% of maximal heart rate, typically at speeds between 1.6 and 1.8 m x s(-1) (3.5 and 4.0 mph), for 10 wk. Subjects agreed not to make changes to their diet. Twelve short-bout walkers, 12 long-bout walkers, and 10 controls completed the study. Relative to controls, VO2max (short-bout, +2.3 +/- 0.1 mL x kg(-1) x min(-1); long-bout, +2.4 +/- 0.1 mL x kg(-1) x min(-1); controls, -0.5 +/- 0.1 mL x kg(-1) x min[-1]) and the VO2 at a blood lactate concentration of 2 mmol x L(-1) increased in walkers (both P < 0.05), with no difference in response between walking groups. Neither heart rate during standard, submaximal exercise nor resting systolic blood pressure changed in a different way in walkers and controls. The sum of four skinfold thicknesses decreased in both walking groups (P < 0.05) but body mass (short-bout, -1.7 +/- 1.7 kg; long-bout, -0.9 +/- 2.0 kg; controls, +0.6 +/- 0.7 kg) and waist circumference decreased significantly only in short-bout walkers. Changes in anthropometric variables did not differ between short- and long-bout walkers. Thus short bouts of brisk walking resulted in similar improvements in fitness and were at least as effective in decreasing body fatness as long bouts of the same total duration.

Adult↗
PubMed1986

Revlens: a new, soft acrylic rubber extended-wear contact lens.

Revlens is a new, soft acrylic rubber extended-wear contact lens. We fitted 21 eyes in 15 patients. The indications included 15 eyes in 10 patients with aphakia due to congenital cataracts. The developmental cataracts were associated with persistent hyperplastic primary vitreous, Down's syndrome, microphthalmos and Peter's anomaly. The remaining five patients included one Tyrosinase negative oculocutaneous albino and four anisometropic amblyopes. Three of the aphakic patients were unable to wear this lens. One preferred her previous rigid lens, another refused any contact lens and went back to glasses, and a third did not adapt to the lens because of social circumstances. Thus 12 of the 15 patients (80%) who were monitored for at least 6 months (average: 9 months) readily accepted this new lens.

Acrylates↗
PubMed1984

Construction and functional analysis of a series of synthetic RNA polymerase III promoters.

RNA polymerase III promoters were constructed by cloning chemically synthesized double stranded analogues of the box A and box B consensus sequences into suitable vectors. In contrast to approaches adopted previously for the analysis of RNA polymerase III promoters, this method has no limitation on the structure and number of variants generated, and allows critical sequences in various permutations to be studied. Furthermore, the series of synthetic polymerase III promoters created constitute a collection of point mutation variants and hence provide a powerful tool for the analysis of nucleotides essential for promoter function. The results demonstrate that these two boxes, when separated by approximately 50 base pairs, are sufficient to direct efficient transcription, and that substitution of certain nucleotides causes reduced template activity.

Base Sequence↗
PubMed1984

Construction and functional analysis of a series of synthetic RNA polymerase III promoters.

RNA polymerase III promoters were constructed by cloning chemically synthesized double-stranded analogues of the box A and box B consensus sequences into suitable vectors. In contrast to approaches adopted previously for the analysis of RNA polymerase III promoters, this method has no limitation on the structure and number of variants generated and allows critical sequences in various permutations to be studied. Furthermore, the series of synthetic polymerase III promoters created constitute a collection of point mutation variants and hence provide a powerful tool for the analysis of nucleotides essential for promoter function. The results demonstrate that these two boxes, when separated by 51 base pairs, are sufficient to direct efficient transcription and that substitution of certain nucleotides causes reduced template activity.

Base Sequence↗
PubMed1983

Directed semisynthetic point mutational analysis of an RNA polymerase III promoter.

The transcription of tRNA and Alu repeat genes in vitro by RNA polymerase III has been shown to be dependent on the presence of two intragenic regions, which contain the consensus sequences RGYNNRRYGG (box A) and GA/TTCRANNC (box B), located 30-60 nucleotides apart. The role of box B and some of its variants was analyzed by a novel method involving the chemical synthesis of double stranded analogues of box B which were subsequently cloned into recombinant vectors carrying box A alone. This method creates a series of semi-synthetic RNA polymerase III promoters and has no limitation on the structure and number of variants which can be generated. The results showed the "wild type" sequence GTTCGAGAC and the sequence GTTCGTGAC (an A to T transversion of the 6th position) were active in promoting RNA polIII transcription. However, the box B sequences CTTCGAGAC and GTACGAGA, where the only departures from the consensus are a G to C and an A to T transversion in the 1st and 3rd positions respectively, were unable to restore promoter function.

Base Sequence↗
PubMedDate not supplied

Urea kinetics during continuous hemofiltration.

Urea kinetic analysis allows for the calculation of the urea distribution volume and urea generation rate. This method was employed in patients with acute renal failure managed by continuous venovenous hemofiltration (CVVH). Based on serial serum urea nitrogen concentration measurements, each patient's treatment course consisted of both steady state and non-steady state periods. Thirteen data sets were obtained from 11 critically ill patients treated with CVVH. The duration of therapy was 9.5 +/- 7.5 days (mean +/- SD). Serum urea nitrogen concentration fell from 114 +/- 32 mg/dl to a steady state value of 79 +/- 17 mg/dl (p < 0.0005). The urea distribution volume was 0.55 +/- 0.11 L/kg (range 0.29-0.73), and the urea generation rate 11.7 +/- 3.1 mg urea N/min (range 7.1-17.3). The steady state serum urea nitrogen concentration had a linear relationship to the rate of urea generation (r = 0.92). Urea kinetic analysis permitted the simultaneous determination of the urea generation rate and distribution volume, on an individualized basis, in patients with acute renal failure treated with CVVH.

Acute Kidney Injury↗
PubMedDate not supplied

Impact of the nutritional regimen on protein catabolism and nitrogen balance in patients with acute renal failure.

BACKGROUND: Patients with acute renal failure are in substantial negative nitrogen balance as a result of their extremely high protein catabolic rates. We prospectively evaluated a series of patients with acute renal failure managed with continuous venovenous hemofiltration to determine which nutritional and nonnutritional variables might influence protein catabolism and nitrogen balance. METHODS: Forty consecutive patients (aged 52 +/- 20 years; mean +/- SD) were monitored for 357 treatment days (average treatment duration 8.9 +/- 8.6 days). All data (including nutritional regimen, laboratory values, APACHE II score, administered blood products, hemofiltration parameters, and medications) were collected daily. RESULTS: For all patients, the mean normalized protein catabolic rate was 1.4 +/- 0.5 g/kg per day. The rate did not differ between those who received nutrition support and those who did not. The net nitrogen deficit was less in those patients receiving nutrition support (-6.0 +/- 5.2 vs -14.0 +/- 5.6 g N/d; p = .02). Using regression techniques (adjusted for the within-person correlation and the previous day's normalized protein catabolic rate), the level of protein and energy provision and the interaction between protein and energy provision were predictive of the normalized protein catabolic rate. Predicted values, using this equation, suggest that at low protein administration rates (< 1 g/kg per day), increasing energy provision may reduce the protein catabolism. However, at this level of protein provision, patients remain in negative nitrogen balance. At protein administration rates necessary to achieve nitrogen balance (approximately 1.5 to 1.8 g/kg per day), protein catabolism may increase. Providing relatively low levels of energy may diminish the magnitude of this increase. CONCLUSION: These results suggest that the optimal nutritional regimen for patients with acute renal failure may require a high-protein (approximately 1.5 to 1.8 g/kg per day) and a relatively low-energy (approximately 25 to 35 kcal/kg per day) content.

Acute Kidney Injury↗