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PubMed2000

[Evaluation of masticatory comminute function using multiple variables--Part II: Analysis of masticatory efficiency from EMG duration].

For analysis of parameters, which can represent stomatognathic function, a possibility for the estimation of masticatory efficiency without analyzing food comminution was shown in Part I. Since there is a necessity for more precise estimation of masticatory efficiency to enable comparison with other parameters, the variance from the central value of food particle size was quantified and a new evaluation of masticatory efficiency, which can be adapted to any comminuted foods and has a good reproducibility was devised. The relationship between the masticatory efficiency originating from the side of comminuted food and the parameters that represent a variance of electromyogram (EMG) duration was analyzed. Then, the total variances of EMG duration, originating from working side masseter, corresponding to the task, which is consumed by food comminution, were calculated. That is the masticatory efficiency, which can be found from the side of EMG. A negative correlation between masticatory efficiencies, originating from the sides of food comminution and power supply was found. Therefore, estimation of masticatory efficiency using EMG measurements from the side of EMG may be possible.

Adult↗

PubMed1999

Variability of adenovirus receptor density influences gene transfer efficiency and therapeutic response in head and neck cancer.

Despite encouraging preclinical studies in many tumor types including head and neck squamous cell carcinoma (HNSCC), initial clinical trials with adenovirus-mediated gene therapy have been disappointing. Although the adenovirus is a "highly efficient vector," it is still limited by the extent of effective in vivo transduction. In our studies with multiple human HNSCC cell lines, we have noted a variation in both in vitro and in vivo responses to the same recombinant adenovirus therapeutic construct. We hypothesize that adenovirus receptor density among tumor cell populations, even of the same histology, greatly influences transduction efficiency and therapeutic results of a variety of adenovirus-based gene therapy strategies. To investigate this hypothesis, the numbers of adenovirus receptors on three well-characterized HNSCC cell lines were determined. Marker and cytokine gene transfer efficiencies as well as therapeutic outcomes after adenovirus-mediated tumor suppressor gene and suicide gene therapies were evaluated and correlated with receptor status. A 5-fold variation in adenovirus receptor density was identified among the HNSCC cell lines (P < 0.002, t test). This variation directly correlated with adenovirus type 5 (Ad5)-mediated green fluorescent protein marker gene and Ad5-interleukin 2 cytokine gene transfer efficiency and resulting protein expression in each individual cell line. The receptor density also directly correlated with therapeutic response after Ad5-thymidine kinase or Ad5-p16 gene transfer in each HNSCC line. The role of the adenovirus receptor in gene transfer efficiency was further supported by recombinant Ad5 fiber knob blocking experiments. The marker gene transfer was increasingly blocked by the same concentration of Ad5 recombinant fiber knob in relation to decreasing levels of adenovirus receptor in the HNSCC lines. An Ad5 recombinant construct that carries the shared coxsackie and adenovirus receptor (CAR) was created and used to up-regulate receptors on each cell line. Ad5-CAR infection significantly increased Ad5-beta-Gal gene transfer efficiency and expression (P = 0.0003, Mann-Whitney test). This increased marker gene expression remained consistent with the established pattern of gene transfer efficiency among the HNSCC cell lines. These data confirm the importance of the adenovirus receptor on individual tumor cell lines with respect to investigating novel adenovirus-mediated gene therapy strategies. This work further supports consideration of assaying adenovirus receptor status, even in tumors of the same histology from patients enrolled in gene therapy clinical trials. Adenovirus receptor status may prove valuable for selecting or stratifying patients as well as assessing outcomes among patients within adenovirus-based cancer gene therapy trials.

Adenoviruses, Human↗

PubMed2001

A prospective evaluation of the efficiency of early postoperative bladder emptying after the Stamey procedure or pubovaginal sling for stress urinary incontinence.

PURPOSE: The pubovaginal sling has been criticized as having a higher incidence of postoperative voiding dysfunction than other surgical approaches for the management of stress urinary incontinence. In 2 similar patient groups we prospectively compared the rates of early postoperative voiding dysfunction after the pubovaginal sling or Stamey procedure. MATERIALS AND METHODS: Between June 1995 and January 1997, 50 consecutive patients underwent the pubovaginal sling or Stamey procedure. Emptying efficiency was measured 48 hours postoperatively by suprapubic catheter in the Stamey group and intermittent catheterization in the pubovaginal sling group. When emptying efficiency was greater than 75%, intermittent catheterization was stopped or the suprapubic catheter was removed. RESULTS: There was no statistically significant difference in emptying efficiency for the first 3 voids using the Dunn multiple comparison method. Median voiding efficiencies were 37%, 43% and 61% with the Stamey procedure in group 1 (mean 43%, 45% and 54%), and 60%, 75% and 75% with the pubovaginal sling in group 2 (mean 49%, 68% and 69%), respectively. The mean number of intermittent catheterizations performed in patients with the pubovaginal sling was 5.7 in less than 1 day. In the Stamey group the suprapubic catheter was removed an average of 6 days postoperatively. The mean duration of hospital stay was similar for the sling and Stamey groups (5.4 versus 6 days, respectively). There were 2 patients in each group who were voiding inefficiently after day 7. Voiding efficiency was restored at 53 and 86 days in the 2 patients with slings and at 18 days in 1 of the 2 who underwent the Stamey procedure, respectively. The second patient who underwent the Stamey procedure was able to void without using the catheter at all, and it was removed 30 days postoperatively when emptying efficiency was confirmed greater than 75%. CONCLUSIONS: These data show that early postoperative voiding dysfunction, measured using bladder emptying efficiency, after the pubovaginal sling is no more common than after the Stamey procedure and help justify the broadened indications for pubovaginal sling for treatment of stress urinary incontinence.

Female↗

PubMed1991

The oxygen content of ocean bottom waters, the burial efficiency of organic carbon, and the regulation of atmospheric oxygen.

Data for the burial efficiency of organic carbon with marine sediments have been compiled for 69 locations. The burial efficiency as here defined is the ratio of the quantity of organic carbon which is ultimately buried to that which reaches the sediment-water interface. As noted previously, the sedimentation rate exerts a dominant influence on the burial efficiency. The logarithm of the burial efficiency is linearly related to the logarithm of the sedimentation rate at low sedimentation rates. At high sedimentation rates the burial efficiency can exceed 50% and becomes nearly independent of the sedimentation rate. The residual of the burial efficiency after the effect of the sedimentation rate has been subtracted is a weak function of the O2 concentration in bottom waters. The scatter is sufficiently large, so that the effect of the O2 concentration in bottom waters on the burial efficiency of organic matter could be either negligible or a minor but significant part of the mechanism that controls the level of O2 in the atmosphere.

Atmosphere↗

PubMed2002

[Molecular conformation and expression efficiency in the hepatocyte targeting gene drug].

OBJECTIVE: To modulate the molecular conformation of the hepatocyte targeting drug to increase exogenous gene expression efficiency in the targeted cell. METHODS: Some specific auxiliary molecules were added to the gene drug its molecular liquid conformation was investigated under the electron-microscope and they were transfected into human hepatoma cell line BEL-7402 in vitro. We detected IFN-gamma gene expression product by ELISA and screened out the most efficient drug molecules. RESULTS: Due to various concentrations of auxiliary molecules, the conformation of hepatocyte targeting drug changed, including floccule, globulous, stringbeads, bacillform and chromosome-like mixture. While the most efficient expression conformation was the bacilliform and chromosome-like mixture and didn't need to inhibit the lysozyme activity, the expression efficiency of such drug molecules was much higher than that of the liposome targeting vector. CONCLUSION: The molecular drug conformation had much influence on targeted gene expression efficiency in gene therapy. Bacilliform and chromosome-like mixture may be the most efficient expression conformation to construct drug molecules in ASOR targeted hepatocyte gene therapy. So we put forward a new concept "chromosome mimic conformation" in screening out the most efficient molecular drug conformation in gene therapy.

Carcinoma, Hepatocellular↗

PubMed2003

[Physiological adaptability of seeding rice genotypes with different P uptake efficiency under low P-deficient stress].

The genotypic differences in P uptake efficiency of three rice varieties (IR74, IR71331 and IR71379) were studied under the P-deficiency condition with hydroponics, and their adaptability to low phosphorus stress about physio-biochemical mechanisms was further studied. The results showed that rice genotypes tolerated low P stress resulted from the co-ordination of P uptake efficiency, internal utilization efficiency and its translocation efficiency. The higher P-efficiency type IR74 and the middle type IR71331 had a higher P uptake efficiency. The rice genotype with higher P-efficiency was characterized by higher activity and desirable kinetic parameters of H2 PO4- uptake, showing lower Km and Cmin, but higher Imax values and relative APase activity, small amount of Km and Cmin. Moreover, under low P stress, the activity of RNase was about ten to fifteen times as high as that of the control (CK), but it had little genotypic differences.

Acid Phosphatase↗

PubMed2002

[Atomization efficiency of graphite furnace in atomic absorption spectrometry].

In this paper, the advance of study of atomization efficiency for graphite furnace atomic absorption spectrometry was reviewed. The fundamental theory and the various calculated equations of atomization efficiency, as well the relationship among beta m, beta i(exp) and beta i(cal) were described. Problems requiring further improvement in the investigation of atomization efficiency of graphite furnace atomic absorption spectrometry were discussed. Peak area atomization efficiency is more practical than peak height. Because the mean residence time (tau R) of atoms in the furnace is larger than tau D (tau D = l2/8D, l is the tube length and D is the diffusion coefficient), calculated peak area atomization efficiency in the furnace is larger than experimental. Part of the atomization efficiency is affected by atomic loss mechanism. An important aspect of researching atomization efficiency is conducted mainly to improve the sensitivity and limit of detection of the analysis method.

Cadmium↗

PubMedDate not supplied

Feeding readiness in preterm infants: the relationship between preterm behavioral state and feeding readiness behaviors and efficiency during transition from gavage to oral feeding.

PURPOSE: The purpose of this secondary analysis was to assess whether alert behavioral states were associated with an increased number of feeding readiness behaviors (FRBs) and whether the number of FRBs were associated with subsequent feeding efficiency in healthy premature infants born between 29 to 35 weeks gestation. STUDY DESIGN AND METHODS: The data were collected as part of a larger study designed to compare the frequency of FRBs and feeding efficiency between control and experimental groups. Data from 21 stable premature infants were included in this secondary analysis. Infants were videotaped immediately prior to each of the first three oral feedings, from which infant behavioral state (IBS) and FRBs were assessed. Feeding efficiency was determined by calculating the ratio of feeding intake to feeding duration. RESULTS: IBS was not a significant predictor of the number of FRBs. The number of FRBs was predictive of feeding efficiency (p <.05). Group assignment was a marginally significant predictor of feeding efficiency (p < .10). Infant sex (p < .05), birthweight (p < .01), gestational age at birth (p <.01), and gestational age at entry (p < .05) were identified as significant predictors of the number of FRBs. Group assignment was marginally significant (p < .10). CLINICAL IMPLICATIONS: Feeding efficiency may be predicted by the increased number of FRBs immediately prior to feeding. An infant's attributes (sex, birth-weight, and gestational age) may relate to feeding efficiency and should be assessed when instituting oral feeding. Assessment of FRBs can be easily incorporated into routine clinical practice.

Attention↗

PubMed2004

Variation in barley yellow dwarf virus transmission efficiency by Rhopalosiphum padi (Homoptera: Aphididae) after acquisition from transgenic and nontransformed wheat genotypes.

The effects of different acquisition access periods (AAPs) and inoculation access periods (IAPs) on the transmission efficiency of barley yellow dwarf luteovirus (BYDV) by Rhopalosiphum padi (L.) (Homoptera: Aphididae) after feeding on transgenic or nontransformed wheat, Triticum aestivum L., genotypes were studied. Three wheat genotypes were tested as virus sources: virus-susceptible 'Lambert' and 'Lambert'-derived transgenic lines 103.1J and 126.02, which express the BYDV-PAV coat protein gene. Lower virus titers were measured in BYDV-infected transgenic plants compared with Lambert. No significant differences in transmission efficiency were detected for R. padi after varying IAPs, regardless of genotype. Transmission efficiency increased with an increase in AAP in all genotypes tested. However, AAPs ranging from 6 to 48 h on Lambert resulted in significantly greater transmission efficiency than similar periods on transgenic 103.1J. Maximum transmission efficiency (70%) was observed after a 48-h AAP on Lambert, whereas the same AAP on 103.1J and 126.02 resulted in a significantly lower transmission efficiency (57%). Contrasts were used to compare the rates of transmission and the theoretical maximum transmission percentage among the different wheat genotypes serving as virus sources. Both parameters were significantly different among genotypes, indicating that viral acquisition from each genotype resulted in a unique pattern of virus transmission by R. padi. The lowest rate of virus transmission after an AAP was observed on 103.1J compared with 126.02 or Lambert. This is likely associated with a lower virus titer in 103.1J. This is the first report of transgenic virus resistance in wheat affecting the transmission efficiency of a virus vector.

Animals↗

PubMed2006

Efficiency of liquid cooling garments: prediction and manikin measurement.

INTRODUCTION: We studied the efficiency of liquid cooling garments (LCG) and their relationship to the insulation of outer clothing, perfusate inlet temperatures, and environmental conditions by both theoretical analysis and thermal manikin (TM) testing. METHODS: An equation to estimate LCG cooling efficiency was developed on the basis of energy balance. Cooling efficiency is a function of the thermal resistance between the TM skin and perfusate in the LCG, the thermal resistance between the environment and the perfusate, and TM skin, ambient, and perfusate temperatures. Three ensembles, a cooling vest (CV) only, CV plus a battle dress uniform (CVB), and CVB plus a battle dress overgarment (CVO), were tested on a sweating TM in dry and wet conditions. The TM surface temperature was maintained at 33 degrees C and the environment was 30 degrees C and 50% RH. The LCG heat removal from the TM was calculated using the power inputs to the TM with and without perfusate flow. RESULTS: The cooling efficiency was increased from approximately 0.45 for CV to approximately 0.70 for CVO in dry experiments and from approximately 0.53 for CV to 0.78 for CVO in wet experiments. CONCLUSION: With additional outer clothing layers, higher thermal resistances increased the rate of heat removal from the TM surface, and decreased heat gain from the ambient environment, thus increasing efficiency. The perfusate inlet temperature had minimal influence on the efficiency. The equations developed can predict cooling efficiency and heat removal rates under a wider range of environmental conditions.

Body Temperature Regulation↗

PubMed1988

The efficiency of lactate dehydrogenase isoenzyme determination for the diagnosis of acute myocardial infarction.

Values for total lactate dehydrogenase (LDH; EC 1.1.1.27) activity and LDH isoenzymes 1 and 2 were determined in 80 patients with acute myocardial infarction (AMI) and in 40 without AMI every 24 hours up to 15 days after admission, when total serum LDH level returned to normal. The sensitivity, specificity, and efficiency of three LDH isoenzyme factors (LDH-1, greater than 90 U/L; LDH-1 greater than LDH-2; LDH-1/LDH ratio, greater than 0.4) for diagnosing AMI were assessed in three groups of patients according to total serum LDH values--group A, LDH level over 600 U/L; group B, 400 to 599 U/L; group C, 225 to 399 U/L--and in five groups of patients according to the time after admission--(1) first 48 hours; (2) three to five days; (3) six to eight days; (4) nine to 11 days; (5) 12 to 15 days. All three factors were found to be highly efficient for diagnosing AMI (91.5% to 97.5%) in groups A and B, but the most efficient factor in each group was LDH-1 value above 90 U/L. In group C, the only efficient factor was the LDH-1 value over 90 U/L (96%). The most efficient factor for diagnosing AMI in relation to time after admission up to 15 days after AMI was the LDH-1 value over 90 U/L (96% to 97.5%). The factors LDH-1 greater than LDH-2 and LDH-1/LDH above 0.4 were more efficient in patients up to five days after AMI (91.5% to 97.5%) than in patients six to 15 days after admission. We conclude that the most efficient LDH value for diagnosing AMI is the absolute value of LDH-1 above 90 U/L. Its superiority over other LDH isoenzyme values is best documented in a group of patients six to 15 days after admission and with only slight to moderate elevation of total serum LDH values (225 to 399 U/L).

Adult↗

PubMed1981

Efficiency of energy retention in genetically obese animals and in dietary-induced thermogenesis.

Genetically obese rodents (ob/ob mice and fa/fa rats) and animals with dietary-induced thermogenesis represent two extremes in efficiency of energy retention: the former deposit dietary energy with high efficiency, whereas the later deposit dietary energy with low efficiency. These differences in efficiency of energy retention must, at the cellular level, be associated with changes in efficiency and/or rate of formation and/or utilization of ATP (and other high energy intermediates). Brown adipose tissue possesses a unique proton-conductance pathway that reduces the efficiency of ATP synthesis. It has been speculated that this pathway is suppressed in obese (ob/ob) mice and accelerated in rats with dietary-induced thermogenesis. Metabolic reactions that alter the rate of ATP utilization in animals include Na+, K+-ATPase and protein turnover. The concentration of Na+, K+-ATPase enzyme unites in skeletal muscle and liver of young adult obese (ob/ob) mice is lower than in tissues of young adult lean mice. There also appear to be alterations in protein turnover in certain tissues of obese (ob/ob) mice, but additional studies are required to determine if whole-body protein turnover is altered in these animals. Data are unavailable on either Na+, K+-ATPase or protein turnover in tissue of animals with dietary-induced thermogenesis. Continuation of studies in these areas should provide a metabolic basis for understanding individual variability in efficiency of energy retention.

Adipose Tissue, Brown↗

PubMed1997

Ventricular and myocardial efficiencies during acute aortic regurgitation in conscious dogs.

BACKGROUND: Alterations in cardiac efficiency may signal pathologic stresses and energetic adaptation during aortic regurgitation (AR). METHODS AND RESULTS: LV systolic function, left coronary blood flow, and AVO2 difference were measured in conscious dogs to assess LV and contractile efficiencies at baseline, 1 day (n=10), 1 week (n=10), and 3 weeks (n=8) of AR. LV systolic function was assessed by the preload recruitable stroke work relationship. Total LV Efficiency (TEFF=SWxHeart Rate/MVO2) and contractile efficiency (CEFF=1/the slope of the MVO2 -pressure-volume area relationship) and steady-state potential energy (PVA-SWxHR), mechanical coupling efficiency (MCE=SWxHR/PVA) were calculated. LV systolic function decreased by 17% at 1 day (P<.05) and by 24% at 3 weeks (P<.05). CEFF decreased from 58+/-8% to 38+/-10% (P<.05) at 1 day, normalized at 1 week, and decreased to 28+/-14% at 3 weeks (P<.05). TEFF was not altered at 1 day and 1 week but decreased by 3 weeks (P<.05). MCE trended downward from baseline of 47+/-5%, reaching significance at 3 weeks (34+/-6%, P<.05). CONCLUSIONS: CEFF decreases acutely, indicating diminished economy of myocardial contraction. CEFF normalizes at 1 week, suggesting adequate compensation. TEFF is not altered in early AR. By 3 weeks, LV systolic dysfunction is accompanied by depressed TEFF, mechanical coupling, and CEFF signaling the onset of decompensated AR. Thus, volume overload of acute AR resulted in early compensation at the expense of myocardial efficiency with subsequent global dysfunction characterized by depressed LV systolic mechanics, mechanical, coupling, and contractile efficiencies.

Acute Disease↗

PubMed1998

Effect of antigen-processing efficiency on in vivo T cell response magnitudes.

T lymphocytes eradicate and provide long-term immunity to infections caused by intracellular pathogens. The mechanisms that determine in vivo T cell response sizes are poorly understood. Although it is speculated that the relative processing efficiency of different epitopes determines the hierarchy of T cell responses following immunization, this hypothesis has not been rigorously tested. We therefore mutagenized the secreted p60 Ag of Listeria monocytogenes to alter the efficiency of T cell epitope generation. Ag-processing efficiencies in cells infected with the different L. monocytogenes mutants ranged from one H2-Kd-associated p60 217-225 epitope generated per 15 intracellularly degraded p60 molecules (1/15) to one epitope per 350 degraded p60 molecules (1/350), i.e., a spectrum encompassing a 20-fold range of efficiencies. Mice infected with L. monocytogenes secreting inefficiently processed p60 (1/350) did not mount p60 217-225-specific T cell responses. However, increasing the efficiency of Ag processing by a factor of 5 to 1/70 restored the T cell response size to normal, while further increases in the efficiency of p60 217-225 generation to 1/50, 1/35, and 1/17 did not further augment specific T cell responses. Our studies demonstrate an Ag-processing threshold for in vivo T cell activation. Surprisingly, once this threshold is achieved, further enhancement of Ag-processing efficiency does not enhance the size of T cell responses.

Amino Acid Sequence↗

PubMedDate not supplied

Technical, scale, and size efficiency in nursing home care: a nonparametric analysis of Connecticut homes.

Maindiratta (1990) questioned the usefulness of the concept of scale efficiency in production as the most productive scale size (MPSS) usually requires altering the scale of output produced. If the decision making unit (DMU) is required to deliver a specific output bundle, then altering output along with the input scale to reach the MPSS is not a valid recommendation. He proposed a measure of the size efficiency of a DMU. In this paper, we apply Data Envelopment Analysis (DEA) to examine the levels of technical, scale, and size efficiency of individual nursing homes providing health care to the elderly. The data used relate to the operations of 140 nursing homes from Connecticut, USA during the year 1982-83. Maindiratta's model is input-oriented. By contrast, our study is output-oriented and we appropriately reformulate Maindiratta's model. The findings show that in several cases size efficiency is less than unity. This suggests that the most efficient production of output would require restructuring of the nursing home under investigation as more than one small unit. We also compare the efficiency levels of 'for-profit' homes with those of 'not-for-profit' homes.

Aged↗

PubMedDate not supplied

Output efficiency of health maintenance organizations in Florida.

We use data envelopment analysis (DEA) to measure the relative technical efficiencies of 28 HMOs licensed to practice in the State of Florida in the autumn of 1994. Health care output measures used in the analysis are number of commercial, Medicare and Medicaid members enrolled in each plan. Inputs to the model are capital assets, total expenditures on the provision of medical services and administrative expenses. We find differences in HMO efficiency scores and loss ratios (defined as the ratio of expenses on the provision of medical services to the total expenses incurred by the organization) across individual plans. Differences in efficiency measures across model type (staff, IPA, combination) and ownership types (for-profit, not-for-profit) are small but significant: staff models and for-profits are more efficient. In a multivariate model, we also find that large HMOs are more efficient and HMOs with Medicaid patients are significantly less efficient than other HMOs.

Ambulatory Care↗

PubMed1998

Measuring hospital cost efficiency with panel data models.

This paper investigated the development of hospital cost efficiency and productivity in Finland in 1988-1994 using a comparative application of parametric and non-parametric panel models. Stochastic cost frontier models with a time-varying inefficiency component were used as parametric methods. As non-parametric methods various DEA models were employed to calculate efficiency scores and the Malmquist productivity index. The results revealed a 3-5% annual average increase in productivity, half of which was due to improvement in cost efficiency and half due to technological change. The results by parametric and non-parametric methods compared well with respect to individual efficiency scores, time-varying efficiency and technological change. The state subsidy reform of 1993 did not seem to have any observable effects on the hospital efficiency.

Cohort Studies↗

PubMed2005

Measuring the productive efficiency and clinical quality of institutional long-term care for the elderly.

The authors consider the association between productive efficiency and clinical quality in institutional long-term care for the elderly. Cross-sectional data were collected from 122 wards in health-centre hospitals and residential homes in Finland in 2001. Productive efficiency was measured in terms of technical efficiency, which was defined as the unit's distance from the (best practice) production frontier. The analysis employed stochastic production frontier estimation, where technical inefficiency in the production function was specified to be a function of ward characteristics and clinical quality of care. Several quality indicators based on the Resident Assessment Instrument, such as prevalence of pressure ulcers and depression with no treatment, were used in the analysis. The results did not reveal systematic association between technical efficiency and clinical quality of care. However, the prevalence of pressure ulcers, indicating poor quality of care was associated with technical efficiency, a fact which highlights the importance of including quality measures in the assessment of efficiency in long-term care.

Aged↗