Search PubMed⌕ Search

Biomedical subjects

L W Moore

Publications and source records attributed to L W Moore.

At least 37 records · Page 2Linked to original sources
PubMed1996

Nutrition in the critical care settings of renal diseases.

Acute catabolic events during the course of renal dysfunction lead to exacerbation of nutritional abnormalities often present in these patients. Whether the renal failure is acute or chronic, the nutritional management of these patients is extremely challenging. Traditional methods of nutritional assessment must be extrapolated to include the effects of the renal dysfunction and renal replacement therapy being used. Cases of patients with acute renal failure, chronic renal failure with an acute insult, pancreas-kidney transplant recipient with delayed graft function, and a liver transplant recipient who developed renal failure are reviewed with emphasis on the nutritional management during the course of illness. Monitoring techniques are reviewed, and comparisons are made to other nutrition support protocols.

Acute Kidney Injury↗
PubMed1996

Correlation between Banff classification, acute renal rejection scores and reversal of rejection.

The Banff classification of acute rejection is based on histologic grades and scores for borderline changes, glomerular, vascular, interstitial and tubular lesions. We reviewed 56 episodes of acute rejection occurring in 44 kidney allograft recipients (30 cadaveric and 14 living donor transplants), comparing Banff classification to degree of reversibility of rejection. Rejection reversal was defined as complete if serum creatinine returned < or = 25% of baseline, partial if creatinine was > 25% to < 75% of baseline, and irreversible if creatinine was > or = 75% of baseline or graft loss occurred. Eight biopsies were classified as borderline (SUM score 1.6 +/- 0.5), 14 grade I (SUM score 3.3 +/- 0.4), 19 grade II (SUM score 4.2 +/- 0.3), and 15 grade III (SUM score 8.5 +/- 0.4). SUM distinguished borderline and grade III rejections, but not grades I and II. Clinically, grade and SUM score correlated with rejection reversal. Complete reversal of rejection occurred in 93% of patients with grade I rejection, while 47% of patients with grade III had irreversible rejection. The mean SUM for complete reversal was 3.9 +/- 0.34 and was different from SUM of partial (6.0 +/- 0.86) and irreversible (8.5 +/- 0.93), P < 0.006. Meanwhile, vascular scores were similar for rejections with complete (0.9 +/- 0.2) or partial (1.0 +/- 0.4) reversal, but significantly higher in those with irreversible rejection (3.0 +/- 0.4, P < 0.000). Likewise, mean scores for tubulitis and interstitial inflammation were significantly higher for irreversible rejection. Resolution of rejection by steroids was correlated to low vascular score (steroid sensitive 0.65 +/- 0.25 vs. steroid resistant 1.42 +/- 0.18, P < 0.01), and low SUM score (steroid sensitive 3.7 +/- 0.5 vs. steroid resistant 5.22 +/- 0.43, P < 0.04). Neither scores for tubulitis nor interstitial cellular inflammation were predictive of steroid sensitivity. These data demonstrate that Banff scoring has clinical relevance in predicting rejection reversal and has implications to first-line therapy of rejection episodes.

Adolescent↗
PubMed1995

Glomerulosclerosis as a determinant of posttransplant function of older donor renal allografts.

Transplantation of kidneys from older donors is being advocated to expand the organ donor pool. However, the prevalence of atherosclerosis and age-induced renal structural alterations account for the variable function of allografts procured from these older donors. Pretransplant biopsies are sometimes used to evaluate kidneys from older donors, but to date there are no defined criteria correlating the extent of structural alterations in these kidneys to subsequent function. We investigated the effect of glomerulosclerosis, a marker for nephrosclerosis, on graft outcome. Sixty-five baseline biopsies of kidney allografts were retrospectively analyzed to identify a referent point of glomerulosclerosis that correlated with inferior graft outcome. Age and death from nontraumatic cerebrovascular injuries were the main correlates for donor glomerulosclerosis (P < 0.001). Allografts with poor function at 6 months defined as serum creatinine > 2.5 mg/dl (n = 13) or nephrectomy (n = 4) had a mean of 20% glomerulosclerosis at the time of implantation compared with only 2% sclerosis in allografts with good function (P < 0.05). Delayed graft function occurred in 22% and 33% of recipients with no glomerulosclerosis and those with less than 20% glomerulosclerosis, respectively. In contrast, patients receiving kidneys with > 20% sclerosis had an 87% incidence of delayed function (P < 0.05). Moreover, graft loss occurred in 7% of recipients of kidneys with less than 20% sclerosis and in 38% of recipients with > 20% sclerosis (P < 0.04). Measurements of serum creatinine in the donors did not distinguish the different degrees of glomerulosclerosis found on biopsy. Our data indicate that donor glomerulosclerosis greater than 20% increases the risk of delayed graft function and poor outcome of transplanted kidneys. Therefore, we advocate the use of routine biopsies of kidneys from older (> 50 yrs) donors and those donors with nontraumatic cerebrovascular accidents, despite seemingly normal preprocurement serum creatinine.

Adolescent↗
PubMed1995

Universal PCR primers for detection of phytopathogenic Agrobacterium strains.

Two PCR primer pairs, based on the virD2 and ipt genes, detected a wide variety of pathogenic Agrobacterium strains. The endonuclease domain of VirD2 protein, which cleaves transferred DNA (T-DNA) border sequences, is highly conserved; primer oligonucleotides specific for the endonuclease portion of virD2 detected all pathogenic strains of Agrobacterium tested. PCR primers corresponding to conserved sequences in ipt, the T-DNA-borne cytokinin synthesis gene, detected only Agrobacterium tumefaciens and distinguished it from Agrobacterium rhizogenes. The virD2 and ipt primer pairs did not interfere with each other when included in the same PCR amplification, and this permitted simultaneous detection of both genes in a single reaction. One nonpathogenic Agrobacterium radiobacter strain contained virD2 but not ipt; we speculate that this strain arose from a pathogenic progenitor through a deletion in the T-DNA. The virD2 primer pair appears to be universal for all pathogenic Agrobacterium species; used together, the primer sets reported here should allow unambiguous identification of Ti plasmid DNA in bacteria isolated from soil and plants.

Bacterial Proteins↗
PubMed1995

Genetic analysis of nonpathogenic Agrobacterium tumefaciens mutants arising in crown gall tumors.

Little is known about the effect of the host on the genetic stability of bacterial plant pathogens. Crown gall, a plant disease caused by Agrobacterium tumefaciens, may represent a useful model to study this effect. Indeed, our previous observations on the natural occurrence and origin of nonpathogenic agrobacteria suggest that the host plant might induce loss of pathogenicity in populations of A. tumefaciens. Here we report that five different A. tumefaciens strains initially isolated from apple tumors produced up to 99% nonpathogenic mutants following their reintroduction into axenic apple plants. Two of these five strains were also found to produce mutants on pear and/or blackberry plants. Generally, the mutants of the apple isolate D10B/87 were altered in the tumor-inducing plasmid, harboring either deletions in this plasmid or point mutations in the regulatory virulence gene virG. Most of the mutants originating from the same tumor appeared to be of clonal origin, implying that the host plants influenced agrobacterial populations by favoring growth of nonpathogenic mutants over that of wild-type cells. This hypothesis was confirmed by coinoculation of apple rootstocks with strain D10B/87 and a nonpathogenic mutant.

Acetophenones↗
PubMed1994

Factors affecting erythropoietin production and correction of anemia in kidney transplant recipients.

Anemia does not correct in many kidney transplant recipients, probably due to iron deficiency or inadequate erythropoietin (Epo) production. We evaluated effects of iron (Fe) availability on correction of anemia in renal transplant recipients and sought to characterize patterns of early Epo production by transplanted kidneys as related to peritransplant factors. In a prospective randomized trial, 51 consecutive renal transplant patients were followed for 6 months. Epo was measured on days 0, 3, 14, 48 and 168 posttransplantation. Fe status was monitored on days 14, 48 and 168. Pts were randomized at day 14 based on Fe status. Iron-deficient (FeD) patients (n = 24) were randomized to receive daily Fe supplementation (FeDs, n = 12) or no supplementation (FeDns, n = 12). Those with normal Fe status (FeN, n = 27) were followed as controls. No differences were found between groups at day 0 for Hct, Cr, Epo, age, dialysis history, or type of donor. Day 3 Creatinine and Hct were similar among groups, while Epo was significantly higher in FeD groups vs FeN (p < 0.004), and continued higher at 6 months. Though each pt improved Hct, most FeDns and FeN were anemic and Fe deficient at 6 months while all FeDs patients had corrected their anemia (p < or = 0.009) and Fe status. Four FeDs patients developed polycythemia. Epo production correlated inversely to cold ischemia time in cadaver renal allografts (p < 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Communicating effectively with elderly surgical patients.

Effective communication promotes trusting, productive nurse/patient relationships. It is the perioperative nurse's responsibility to establish effective communication with each patient. Perioperative nurses strive to provide quality care to all patients, including the elderly. Communication barriers often do exist, however, between nurses and elderly patients. Perioperative nurses are challenged, therefore, to recognize potential communication barriers and to manage each nurse/patient relationship accordingly. Clear communication between nurse and patient enhances the elderly patient's ability to progress smoothly through surgery and recovery.

Aged↗
PubMed1993

Fate of Agrobacterium radiobacter K84 in the environment.

Agrobacterium radiobacter K84 is an effective, commercially applied, biological control agent for the plant disease crown gall, yet little is known about the survival and dissemination of K84. To trace K84 in the environment, spontaneous antibiotic-resistant mutants were used. Growth rates and phenotypes of streptomycin- or rifampin-resistant K84 were similar to those of the parental K84, except the rifampin-resistant mutant produced less agrocin 84 as determined by bioassay. K84 and a strain of Agrobacterium tumefaciens established populations averaging 10(5) CFU/g in the rhizosphere of cherry and persisted on roots for 2 years. K84 established rhizosphere populations between 10(4) and 10(6) CFU/g on cherry, ryegrass, and 11 other herbaceous plants. Populations of K84 declined substantially in fallow soil or water over a 16-week period. K84 was detected in the rhizosphere of ryegrass located up to 40 cm from an inoculum source, indicating lateral dissemination of K84 in soil. In gall tissue on cherry, K84 established populations of 10(5) CFU/g, about 10- to 100-fold less than that of the pathogen. These data demonstrate that K84 persists for up to 2 years in a field environment as a rhizosphere inhabitant or in association with crown gall tissue.

Drug Resistance, Microbial↗
PubMed1992

Urea kinetics evaluation of hemodialysis and CAPD patients.

Urea kinetics have been used to measure adequacy of hemodialysis. The role of urea kinetics in CAPD has not been clearly established. Using urea kinetics, we studied 71 hemodialysis and 71 CAPD patients. Age was 53 +/- 12 and 45.8 +/- 12 respectively. Urea kinetics in hemodialysis were studied in the standard manner. CAPD patients collected 24 hr, dialysate fluid to measure urea, creatinine, glucose and protein. Urine was collected for 24 hr. to measure urea and creatinine. Protein catabolic rate (pcr) was calculated from the total amount of urea cleared in 24 h. Both groups of patients had similar body weight. Kt/V in CAPD (0.65 +/- 0.1) was at a level considered underdialysis for hemodialysis. In both groups, pcr increased as Kt/V increased. However, CAPD patients had levels of pcr higher than hemodialysis patients at the same level of Kt/V. BUN, serum albumin and serum potassium were significantly lower in CAPD patients. Patients who dialyze more, eat more. Differences in protein intake may be due to a more liberal diet in CAPD, patient selection, removal of middle molecules, or better control of the acidosis.

Adult↗
PubMed1991

Evaluation of hemodialysis patients treated with erythropoietin.

We evaluated 20 hemodialysis patients who had been treated with erythropoietin (Epo). All patients had hemoglobin levels below 8.5 g/dL. They were randomized to receive either Epo (100 U/kg) or placebo three times per week for 12 weeks. All patients on Epo had a significant (P less than 0.001) elevation of hematocrit levels (19.7% v 35.7%). They also had a significant (P less than 0.05) increase in midweek predialysis blood urea nitrogen (BUN) levels, 27.8 versus 29.6 mmol/L (78 v 83 mg/dL), and serum phosphorus, 1.8 versus 2.1 mm/L (5.7 v 6.6 mg/dL). Protein catabolic rate also increased significantly (P less than 0.05). No changes were seen in the levels of serum creatinine and potassium, but episodes of hyperkalemia were more frequent in patients on Epo. No changes were seen in patients on placebo. When hematocrit increased, the clearance of blood-water for urea decreased 9%, and the clearance of creatinine, potassium, and phosphorus decreased 15%. Patients on Epo increased both their appetite and protein intake. More frequent episodes of hyperkalemia and elevated phosphorus level resulted from a combination of increased intake and decreased dialyzer clearance. We may need blood-water clearance to calculate Kt/V.

Adult↗
PubMed1991

Evaluation of CAPD prescription.

Adequacy of CAPD has not been established. The recommendation is a Kt/V (K, total urea clearance in ml/min; t. time in minutes on dialysis; and V, total body water which is the volume of distribution of urea) greater than 1.5/week and/or a creatinine clearance (residual + dialysis) greater than 40 l/week/1.73 m2. We followed 20 CAPD patients for 38.6 +/- 28 mo. We measured blood urea nitrogen, serum creatinine, body weight, residual renal function (Kr), normalized protein catabolic rate (NPCR), Kt/V/week and creatinine clearance (CC) l/w/1.73 m2. We obtained the following values: B Wt 72 +/- 16 kg, BUN 56 +/- 13 mg/dl, s. Cr. 12.6 +/- 5 mg/dl, Kr 0.6 +/- 1 ml/min, NPCR 0.84 +/- 0.3 g/kg/day, Kt/V/week 1.8 +/- 0.3 and CC 50.4 +/- 10 l/w/1.73 m2. Patients dialyzed with a wide range of prescription. There was a good correlation between Kt/V and CC. There was no correlation between the dialysis prescription changes in weight and biochemical determinations. There was a direct correlation between Kt/V and NPCR: patients who were dialyzed more eat more. Of the 20 patients, 10 had 24 hospitalizations, and of these were 12 due to peritonitis. Dialysis prescription and biochemical findings of these patients did not differ significantly from nonhospitalized patients. Larger prospective studies are necessary to determine the adequate range of CAPD prescription and its relationship to morbidity and mortality.

Adult↗
PubMed1991

The efficacy of nutrition support in infected patients with chronic renal failure.

Patients with chronic renal failure are at considerable nutritional risk due to restricted diets, poor intake, and dialysis-related protein losses; therefore, they often require specialized nutrition support. It is difficult, however, to gauge the success of the intervention, since the gold standard nitrogen balance cannot be easily employed. We examined the usefulness of three visceral proteins, insulinlike growth factor 1 (IGF-1), fibronectin (FBN), and prealbumin (PA), as markers of nutrition support efficacy in patients with chronic renal failure. Fourteen patients receiving enteral (1) or parenteral (13) nutrition were studied for 7-28 days. The six males and eight females attained intakes of protein and nonprotein energy of 1.3 +/- 0.3 (mean +/- SD) g/kg/day and 34 +/- 6 kcal/kg/day, respectively. Blood samples taken on days 1, 4, 7, 14, 21, and 28 were assayed for IGF-1, FBN, and PA concentrations. Protein levels were correlated with cumulative nonprotein energy and protein intake. Concentrations of IGF-1 at baseline (0.90 +/- 0.48 U/ml) rose significantly by day 4 (1.35 +/- 0.78 U/ml) and remained significantly above baseline at days 7 (1.44 +/- 0.68 U/ml), 14 (1.63 +/- 1.05 U/ml), and 28 (1.59 +/- 0.98 U/ml). Baseline FBN (113 +/- 53 micrograms/ml) and PA (15.3 +/- 7.8 mg/dl) concentrations rose significantly by day 28 (FBN, 163 +/- 51 micrograms/ml; PA, 24.6 +/- 19.0 mg/dl). The PA concentrations correlated significantly with cumulative nonprotein calories and cumulative protein intake (r = 0.37, p less than 0.01; r = 0.43, p less than 0.01, respectively). Both IGF-1 and PA show promise as markers of nutrition support efficacy in this complex patient population.

Adult↗
PubMed1990

Extended Host Range of Agrobacterium tumefaciens in the Genus Pinus.

Two-to 4-month-old seedlings of nine pine species (Pinus eldarica Medw., Pinus elliottii Engelm., Pinus jeffreyi Grev. & Balf., Pinus lambertiana Dougl., Pinus ponderosa Laws., Pinus radiata D. Don, Pinus sylvestris L., Pinus taeda L., Pinus virginiana Mill), Douglas fir (Pseudotsuaa menziesii (Mirb.) Franco) and incense cedar (Libocedrus decurrens Torr.) were inoculated with five strains of Agrobacterium tumefaciens. Transformation occurred in all conifer species tested as determined by gall formation and opine production. The frequency of gall formation varied by host species, by bacterial strain, and was related to the age of the stem when inoculated. Galls were visible 8 to 12 weeks after inoculation and were small (often less than 2.5 millimeters in diameter). Fewer than half (230 of 502) of the galls originally formed on the trees were present after 1 year, and 26 of these grew to diameters greater than 2 centimeters. The majority of these larger galls (18 of 26) were found in P. radiata. Bacterial strain-specific opines were found in 67 of the 81 gall tissues sampled.

Journal Article↗
PubMed1990

Potential of Agrobacterium tumefaciens and Octopine-Utilizing Fluorescent Pseudomonas Strains To Attach to Susceptible Potato Tissues.

The binding characteristics of two octopine-catabolizing pseudomonads, Pseudomonas fluorescens B99A and E175D, which were isolated from crown galls, have been examined. The binding of strain B99A to potato disks was very weak, followed a Freundlich isotherm, and was temperature and pH independent. Strain E175D displayed strong attachment and followed a Langmuir isotherm. Despite these fundamental differences in binding characteristics, when each strain was placed in competitive binding assays with either Agrobacterium tumefaciens B6 or A. tumefaciens ATCC 15955, the number of bound pseudomonad cells decreased compared with those obtained in independent trials. Furthermore, the binding of A. tumefaciens cells was increased. In prebinding experiments, in which the potato disks were bound with the pseudomonads before exposure to the agrobacteria, the number of bound pseudomonad cells again decreased. This implies that increased desorption was occurring. In these prebinding studies, the numbers of bound A. tumefaciens ATCC 15955 increased, but the number of bound A. tumefaciens B6 remained the same. The mechanism for this observed synergism on the binding of agrobacterial cells and the depression in bound pseudomonad cells is believed to be alterations in the electrostatic or ionic charges on the plant and bacterial cell surfaces. The synergistic effect on A. tumefaciens undermines the use of these pseudomonads as potential biocontrol agents for crown gall.

Journal Article↗
PubMed1990

Growth of Octopine-Catabolizing Pseudomonas spp. under Octopine Limitation in Chemostats and Their Potential To Compete with Agrobacterium tumefaciens.

The growth characteristics of five octopine-catabolizing pseudomonads have been determined in batch and continuous cultures. All five strains belonged to rRNA homology group I and showed a more psychrotrophic growth pattern than did Agrobacterium tumefaciens B6 and ATCC 15955. In chemostats limited by octopine, either as the source of carbon and nitrogen or the sole source of nitrogen, maximum specific growth rates and substrate affinities were lower than those in chemostats limited by glutamate. These growth dynamics were similar to those observed for Agrobacterium strains B6 and ATCC 15955 even though the catabolic genes and pathways are believed to be different in the two genera. An analysis of the yields in octopine-limited chemostats indicated that the use of octopine as the sole source of carbon and nitrogen was grossly inefficient. Octopine and presumably lysopine and octopinic acid provided a better source of nitrogen than of carbon. One of the Pseudomonas fluorescens strains, E175D, was able to produce its highest yield on octopine as a nitrogen source. Competition models formulated on pure culture parameters indicated that two of the Pseudomonas spp. would dominate A. tumefaciens B6 and ATCC 15955 when in simple competition for octopine as a limiting substrate.

Journal Article↗
PubMed1990

Competition of Octopine-Catabolizing Pseudomonas spp. and Octopine-Type Agrobacterium tumefaciens for Octopine in Chemostats.

The ability of two octopine-catabolizing Pseudomonas spp. and two virulent octopine-type Agrobacterium tumefaciens to compete for substrates has been examined in chemostats. In dual cultures with octopine or glutamate as the limiting carbon or nitrogen source, Pseudomonas fluorescens B99A and E175D always dominated over A. tumefaciens B6 or ATCC 15955. The growth dynamics of each strain in pure culture indicated that some form of antagonism was occurring in dual culture to permit the predominance of the pseudomonads under certain conditions. Although both pseudomonads fluoresce, pyoverdine was not responsible for the observed inhibition. An unidentified antibiotic secreted by both pseudomonads is believed to be responsible. A. tumefaciens B6 grew synergistically in the presence of P. fluorescens B99A with octopine as the limiting nitrogen source. This behavior of Agrobacterium strain B6 may help overcome its grossly inefficient use of octopine as previously reported. The ability of these two pseudomonads to outcompete the agrobacteria under all conditions tested raises the possibility that under field conditions, infectious agrobacteria may be succeeded by opine-catabolizing pseudomonads around crown gall tumors and in the rhizosphere.

Journal Article↗