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PubMedDate not supplied

Tissue distribution and penetration of 5-ALA induced fluorescence in an amelanotic melanoma after topical application.

BACKGROUND: Photodynamic therapy (PDT) following topical application of 5-aminolevulinic acid (ALA) is increasingly employed for several types of malignancies. However, data with respect to tissue penetration and distribution of ALA-induced porphyrins after topical application are scarce. Therefore, it was our aim to study tissue distribution and the penetration potency of topically applied ALA. MATERIAL AND METHODS: We used Syrian golden hamsters implanted with the amelanotic melanoma A-Mel-3 growing in a transparent dorsal skinfold chamber. ALA was topically applied in aqueous solution at a concentration of 3% for 4 hours. The fluorescence pattern was quantified by fluorescence microscopy and digital image analysis from cryosections and given as percentage of a reference standard in medians (25%, 75% quartiles). RESULTS: Fluorescence intensities in tumors were 90.8% (56.2%, 115.2% of a reference standard, p < 0.01 vs. normal tissue) significantly exceeding normal surrounding host tissue yielding fluorescence intensities of 12.1% (9.1%, 16.1%). The tumor selectivity, that is the ratio of fluorescence intensities between tumor and normal tissue, was 7.3 (6.1, 9.1). For superficial tumors with a thickness of approximately 1 mm no fluorescence gradients after topical application of ALA could be observed. CONCLUSION: In superficial cancerous lesions the fluorescence distribution of ALA induced porphyrins is tumor selective without significant fluorescence gradients throughout the tumor. Thus, by optimising the treatment modalities for topical ALA-PDT an enhanced efficacy and selectivity will be reached.

Administration, Topical↗
PubMed1998

Random vs. systematic sampling from administrative databases involving human subjects.

OBJECTIVE: Two sampling techniques, simple random sampling (SRS) and systematic sampling (SS), were compared to determine whether they yield similar and accurate distributions for the following four factors: age, gender, geographic location and years in practice. METHOD: Any point estimate within 7 yr or 7 percentage points of its reference standard (SRS or the entire data set, i.e., the target population) was considered "acceptably similar" to the reference standard. The sampling frame was from the entire membership database of the Canadian Chiropractic Association. The two sampling methods were tested using eight different sample sizes of n (50, 100, 150, 200, 250, 300, 500, 800). From the profile/characteristics, summaries of four known factors [gender, average age, number (%) of chiropractors in each province and years in practice], between- and within-methods chi 2 tests and unpaired t tests were performed to determine whether any of the differences [descriptively greater than 7% or 7 yr] were also statistically significant. The strengths of the agreements between the provincial distributions were quantified by calculating the percent agreements for each (provincial pairwise-comparison methods). Any percent agreement less than 70% was judged to be unacceptable. RESULTS: Our assessments of the two sampling methods (SRS and SS) for the different sample sizes tested suggest that SRS and SS yielded acceptably similar results. Both methods started to yield "correct" sample profiles at approximately the same sample size (n > 200). CONCLUSION: SS is not only convenient, it can be recommended for sampling from large databases in which the data are listed without any inherent order biases other than alphabetical listing by surname.

Age Factors↗
PubMed2005

Integration of metrological principles in a proficiency-testing scheme in the field of water analysis.

Measurement traceability is universally recognised as one of the basic prerequisites for comparability of results obtained in different laboratories and is a basic aspect of metrological sciences such as analytical chemistry. This requirement is underscored by the increasing adoption of standards and measurement quality systems, such as laboratory accreditation against ISO/IEC 17025. Testing laboratories ensure traceability of their measurement results by using appropriate reference standards for calibration of instruments and control of measurement processes. For routine work in the field of water analysis, these standards are usually commercial solutions or in-house solutions prepared from "pure" products. Therefore, laboratories should demonstrate that their use of reference standards is appropriate and sufficient, which can be done by participation in an appropriate proficiency-testing scheme. The paper reports how measurement traceability of results from field laboratories (nitrite nitrogen, nitrate nitrogen, chloride and sulphate; all in water) can be demonstrated by participation in a proficiency-testing scheme based on reference values.

Journal Article↗
PubMed1999

Variables that affect assays for plasma cytokines and soluble activation markers.

Cytokines and soluble immune activation markers that reflect cytokine activities in vivo are increasingly being measured in plasma, serum, and other body fluids. They provide useful diagnostic and prognostic information as well as insight into disease pathogenesis. Assays of neopterin, beta2-microglobulin, soluble interleukin-2 receptor, and soluble tumor necrosis factor receptor type II as well as of the cytokines tumor necrosis factor alpha and gamma interferon (IFN-gamma) were evaluated by using serum and plasma samples of human immunodeficiency virus (HIV)-positive and HIV-negative subjects. Many factors were found to influence the outcomes of these assays. Substantial differences in apparent levels of analytes were frequently found when enzyme-linked immunosorbent assay (ELISA) kits from different manufacturers were used. In some cases, differences were found in the standards provided by separate manufacturers. Furthermore, the analytic results from different lots of ELISA kits supplied by single manufacturers differed by as much as 50%. The need for uniformity in the standards for quantitative assays was clearly illustrated. International reference standards are available for cytokines but not for soluble cytokine receptors or soluble activation markers. Marker levels in serum or in plasma were similar except those for IFN-gamma. Most of the analytes were stable under several storage conditions. Thus, batch testing of frozen stored samples is feasible. The findings indicate that for longitudinal studies, the levels of cytokines and immune activation markers in plasma or serum should be measured by using preverified reagents from one manufacturer. The quality of laboratory performance can have an impact on clinical relevance. Proficiency testing and external quality assurance programs can help to develop the needed consensus.

Antigens, CD↗
PubMed2003

Study of Mimusops elengi bark in experimental gastric ulcers.

The present study was designed to investigate the effect of Mimusops elengi (Sapotaceae) against experimental gastric ulcers. The 50% alcoholic extract of Mimusops elengi (Ext E) and its different fractions namely ethyl acetate (Ext E1), n-butanol (Ext E2), methanol (Ext E3) and aqueous (Ext E4) were studied (p.o.) against ethanol-induced gastric damage. Ext E1 was also studied in ethanol-induced, pylorus-ligated and water-immersion plus stress-induced gastric ulcer models. Ranitidine HCl (80 mg kg(-1)) was used as a reference standard. In ethanol-induced gastric ulcer model, pantoprazole (20 mg kg(-1)) was also used as a reference standard. Ext E1 tested in mice up to the dose of 5000 mg kg(-1) (p.o.) did not produce any sign of toxicity. Ext E at the doses of 50, 100, 300 and 500 mg kg(-1) and its different fractions (100 mg kg(-1)) showed reduction in gastric ulceration (P < 0.05). Ext E1 at the doses of 10, 50 and 100 mg kg(-1) showed dose-dependent inhibition of gastric lesions against ethanol-induced gastric damage. In 19 h pylorus-ligated animals, Ext E1 at 50 and 100 mg kg(-1) doses showed significant reduction in ulcer index (P < 0.05). Significant reduction was also observed in total acidity, volume of gastric acid secretion, total acid output and pepsin activity (P < 0.05) when compared with the control group. Besides, Ext E1 showed increase in the mucosal glycoproteins that was evident from significant rise in total carbohydrates to protein ratio (TC:PR ratio) (P < 0.05), which is an indication of mucin activity. Ext E1 also showed protection against water-immersion plus stress-induced gastric lesions that was evident from dose-dependent decrease in ulcer index (P < 0.05), score for intensity (P < 0.05) and total lesion area (P < 0.05) when compared with the control group. It can be concluded from our study that Ext E1 possesses anti-ulcer activity against experimental gastric ulcers. The mechanism of anti-ulcer activity can be attributed to decrease in gastric acid secretory activity along with strengthening of mucosal defensive mechanisms.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2005

The need for energy equilibrium.

Human bioenergetics has been extensively assessed by means of field proxies (ie, cardiorespiratory fitness field tests) during the last two decades. A systematic review of the germane literature, however, suggests considerable controversy as to whether the present tests lead to valid measurements of energy expenditure/utilisation. The present paper suggests that current modalities of field testing being used as predictive models for bioenergetics may suffer from methodological limitations, stemming primarily from inappropriate design. A major weakness in the theoretical basis of proxies is that, although based on field measurements, it seeks to predict laboratory bioenergetics which, in turn, are used to provide information on field performance. Hence, it seems reasonable that the number of transformations increases the potential for error and may have significant impact on the prediction of bioenergetics. Recent studies asserted the importance of achieving 'energy equilibrium' between the reference standard and each proxy. The suggested approach involves designing proxies that closely simulate each laboratory protocol used as reference standard. The theoretical bases of previous and contemporary approaches are discussed in an attempt to increase the validity of current proxy assessments.

Energy Metabolism↗
PubMed2006

The PRIMA study: presentation ischaemia-modified albumin in the emergency department.

OBJECTIVES: To investigate the diagnostic accuracy of presentation ischaemia-modified albumin (IMA), in addition to cardiac troponin I (TnI), as a strategy to rapidly ascribe low risk to patients with chest pain attending an emergency department, and to determine whether IMA has the potential to reduce transit time in emergency departments. METHODS: A prospective observational study was carried out in two emergency departments (belonging to the John Radcliffe Hospital, Oxford, UK; and the Frenchay Hospital, Bristol, UK) of similar size. Consecutive adult patients presenting with features of possible ischaemic cardiac chest pain and a normal electrocardiogram were eligible. The index test (measurement of IMA and TnI at presentation) and reference standard (delayed TnI measurement, taken at least 8 h after pain onset) were applied to all recruited patients. All clinicians were blinded to the results of the index test. Assays were carried out in a single laboratory using standard techniques. RESULTS: 399 patients were recruited; 277 patients had a result for both the index test and reference standard. The sensitivity was 97.6% (95% confidence interval (CI) 87.4 to 99.9), negative predictive value 97% (95% CI 84.2 to 99.9) and specificity 13.6% (95% CI 9.5 to 18.7). Sensitivity analysis showed similar findings in three alternative scenarios. Receiver operating characteristic analysis indicated that a different "cut-off" value for IMA would not improve the properties of the test. The median potential time saved (n = 268) was 6 h and 10 min. CONCLUSION: The diagnostic accuracy of presentation IMA in this study does not support its use as an effective risk stratification tool for patients with chest pain in the emergency department. The sensitivity is insufficiently high, with a small number of false negatives undermining the safety of the test. Frequent false positives produce a low specificity that limits the practical value of the test.

Adult↗
PubMed2005

Personal computer versus workstation display: observer performance in detection of wrist fractures on digital radiographs.

PURPOSE: To retrospectively compare the accuracy of observer performance with personal computer (PC) compared with that with dedicated picture archiving and communication system (PACS) workstation display in the detection of wrist fractures on computed radiographs. MATERIALS AND METHODS: This study was conducted according to the principles of the Declaration of Helsinki (2002 version) of the World Medical Association. The institutional clinical board approved the study; informed consent was not required. Seven observers independently assessed randomized anonymous digital radiographs of the wrist from 259 subjects; 146 had fractures, and 113 were healthy control subjects (151 male and 108 female subjects; average age, 33 years). Follow-up radiographs and/or computed tomographic scans were used as the reference standard for patients with fractures, and follow-up radiographs and/or clinical history data were used as the reference standard for controls. The PC was a standard hospital machine with a 17-inch (43-cm) color monitor with which Web browser display software was used. The PACS workstation had two portrait 21-inch (53-cm) monochrome monitors that displayed 2300 lines. The observers assigned scores to the radiographs on a scale of 1 (no fracture) to 5 (definite fracture). Receiver operating characteristic (ROC) curves, sensitivity, specificity, and accuracy were compared. RESULTS: The areas under the ROC curves were almost identical for the PC and workstation (0.910 vs 0.918, respectively; difference, 0.008; 95% confidence interval: -0.029, 0.013). The average sensitivity with the PC was almost identical to that with the workstation (85% vs 84%, respectively), as was the average specificity (82% vs 81%, respectively). The average accuracy (83%) was the same for both. CONCLUSION: The results of this study showed that there was no difference in accuracy of observer performance for detection of wrist fractures with a PC compared with that with a PACS workstation.

Adult↗
PubMed2006

Drug compatibility with new polyolefin infusion solution containers.

PURPOSE: The compatibility of new polyolefin (VISIV) containers with seven drugs that have exhibited sorption to polyvinyl chloride (PVC) containers and sets and an additional four drugs that have exhibited leaching of plasticizer or other polymer matrix components from PVC containers and sets was studied. METHODS: For the sorption portion of the study, amiodarone hydrochloride, carmustine, regular human insulin, lorazepam, nitroglycerin, sufentanil citrate, and thiopental sodium and their respective reference standards were used. For the leaching portion of the study, docetaxel, paclitaxel, tacrolimus, teniposide, and diethylhexyl phthalate (DEHP) reference standard, were used. A 350-mL quantity of each test admixture was prepared, and 100-mL aliquots were transferred into three of the VISIV containers. The containers were stored at ambient temperature and exposed to fluorescent light. Samples for analysis were taken initially and after 24 hours for all drugs except carmustine, which was evaluated for only 6 hours because of its limited stability. High-performance liquid chromatography was used to evaluate each test solution. RESULTS: Of the seven drugs subject to sorption to PVC, only insulin showed a substantial loss in the VISIV containers. Carmustine exhibited a loss consistent with the drug's known chemical stability. None of the drugs that are known to leach plastic components, such as DEHP plasticizer, from PVC equipment exhibited any leached components in the VISIV containers. CONCLUSION: Of the drugs tested, only insulin exhibited sorption to the new VISIV polyolefin containers. No leaching of plastic components, such as plasticizer, from the containers was found with any of the surfactant-containing drugs.

Adsorption↗
PubMed2000

Which role for amisulpride in rehabilitation of schizophrenic patients with acute exacerbation?

Amisulpride is a substituted benzamide derivative with selective binding to the D2/D3 dopamine receptor. In patients, a beneficial effect on negative signs has been demonstrated for doses up to 300 mg daily. On the other hand, amisulpride demonstrate efficacy in the treatment of classical form of schizophrenia at higher doses (400 to 800 mg/day up to 1,200 mg/day at the maximum). Five studies that included acutely ill schizophrenic patients are reviewed. All were double blind, randomized parallel group studies and the primary efficacy criterion was the BPRS total score. In these study amisulpride was at least as efficacious as haloperidol (10-30 mg), risperidone (8 mg daily), or flupentixol (25 mg daily) in controlling positive symptoms, but was significantly more effective than haloperidol on secondary negative symptoms. When quality of life (QLS) was assessed, amisulpride led to a better improvement than haloperidol. In the long term treatment of schizophrenia, amisulpride maintained antipsychotic efficacy over a 12-month period in an open randomized study. In this study, amisulpride led to a better improvement on Global Assessment of Functioning than haloperidol, the standard reference drug. Furthermore, amisulpride has a favorable benefit/risk profile and induces fewer extrapyramidal side effects than haloperidol the standard reference drug. Therefore, amisulpride is proposed for first-line treatment of schizophrenia in acute exacerbations. It contributes to favor a better social rehabilitation of schizophrenic patients.

Acute Disease↗
PubMed2001

The rational clinical examination. Does this patient have a torn meniscus or ligament of the knee? Value of the physical examination.

CONTEXT: While most meniscal or ligamentous knee injuries heal with nonoperative treatments, a subset should be treated with arthroscopic or open surgery. OBJECTIVE: To analyze the accuracy of the clinical examination for meniscal or ligamentous knee injuries. DATA SOURCES: MEDLINE (1966-December 31, 2000) and HealthSTAR (1975-December 31, 2000) databases were searched for English-language articles describing the diagnostic accuracy of individual examination items for the knee and a combination of physical examination items (composite examination). Other data sources included reference lists from relevant articles. STUDY SELECTION: Studies selected for data extraction were those that compared the performance of the physical examination of the knee with a reference standard, such as arthroscopy, arthrotomy, or magnetic resonance imaging. Eighty-eight articles were identified, of which 23 (26%) met inclusion criteria. DATA EXTRACTION: A rheumatologist and an orthopedic surgeon independently reviewed each article using a standardized rating scale that scored the assembly of the study, the relevance of the patients enrolled, the appropriateness of the reference standard, and the blinding of the examiner. DATA SYNTHESIS: Summary likelihood ratios (LRs) were estimated from random effects models. The summary LRs for physical examination for tears of the anterior cruciate ligament, using the anterior drawer test, were 3.8 (95% confidence interval [CI], 0.7-22.0) for a positive examination and 0.30 (95% CI, 0.05-1.50) for a negative examination; the Lachman test, 25.0 (95% CI, 2.7-651.0) and 0.1 (95% CI, 0.0-0.4); and the composite assessment, 25.0 (95% CI, 2.1-306.0) and 0.04 (95% CI, 0.01-0.48), respectively. The LRs could not be generated for any specific examination maneuver for a posterior cruciate ligament tear, but the composite assessment had an LR of 21.0 (95% CI, 2.1-205.0) for a positive examination and 0.05 (95% CI, 0.01-0.50) for a negative examination. Determination of meniscal lesions, using McMurray test, had an LR of 1.3 (95% CI, 0.9-1.7) for a positive examination and 0.8 (95% CI, 0.6-1.1) for a negative examination; joint line tenderness, 0.9 (95% CI, 0.8-1.0) and 1.1 (95% CI, 1.0-1.3); and the composite assessment, 2.7 (95% CI, 1.4-5.1) and 0.4 (95% CI, 0.2-0.7), respectively. CONCLUSION: The composite examination for specific meniscal or ligamentous injuries of the knee performed much better than specific maneuvers, suggesting that synthesis of a group of examination maneuvers and historical items may be required for adequate diagnosis.

Anterior Cruciate Ligament Injuries↗
PubMed1987

Determinants of birth-weight in the new territories of Hong Kong.

Weights of babies born in the Prince of Wales Hospital, Hong Kong, in its first 2 years of operation were studied, and compared with previous reports. Birth-weight in Hong Kong appears to have increased significantly in recent years. The method of data collection effects reference standards of birth-weight. The effect of different methods of data collection and statistical treatment of data for providing reference standards of birth-weight are discussed. In this series average birth-weight increased by 6.8 g per year of maternal age, 13.3 g per cm of maternal height, 42.5 g per previous baby and 104.9 g per week of gestational age; males were 110 g heavier than females. The effects of parity became significant at 35 weeks, and that of maternal age and height at 36 weeks; the effect of fetal sex was significant from 38 weeks onwards.

Birth Weight↗
PubMed2003

Diagnosing painful sacroiliac joints: A validity study of a McKenzie evaluation and sacroiliac provocation tests.

Research suggests that clinical examination of the lumbar spine and pelvis is unable to predict the results of diagnostic injections used as reference standards. The purpose of this study was to assess the diagnostic accuracy of a clinical examination in identifying symptomatic and asymptomatic sacroiliac joints using double diagnostic injections as the reference standard. In a blinded concurrent criterion-related validity design study, 48 patients with chronic lumbopelvic pain referred for diagnostic spinal injection procedures were examined using a specific clinical examination and received diagnostic intraarticular sacroiliac joint injections. The centralisation and peripheralisation phenomena were used to identify possible discogenic pain and the results from provocation sacroiliac joint tests were used as part of the clinical reasoning process. Eleven patients had sacroiliac joint pain confirmed by double diagnostic injection. Ten of the 11 sacroiliac joint patients met clinical examination criteria for having sacroiliac joint pain. In the primary subset analysis of 34 patients, sensitivity, specificity and positive likelihood ratio (95% confidence intervals) of the clinical evaluation were 91% (62 to 98), 83% (68 to 96) and 6.97(2.70 to 20.27) respectively. The diagnostic accuracy of the clinical examination and clinical reasoning process was superior to the sacroiliac joint pain provocation tests alone. A specific clinical examination and reasoning process can differentiate between symptomatic and asymptomatic sacroiliac joints

Adult↗
PubMed2003

Ultrasound screening of the lambdoid suture in the child with posterior plagiocephaly.

BACKGROUND: The child with posterior plagiocephaly may have positional molding or unilateral lambdoid synostosis. Molding responds to conservative treatment, lambdoid synostosis requires surgical reconstruction. CT is diagnostic, but uses ionizing radiation, may need sedation, and the incidence of lambdoid fusion is only 2-3%. OBJECTIVE: The purpose of this prospective study was to evaluate ultrasound as a screening test of lambdoid sutural patency using CT as the reference standard. MATERIALS AND METHODS: In total, 41 children having head CT examinations were enrolled over 6 months. Of those, 29 were referred for abnormal head shape and suspected synostosis, of whom two had lambdoid fusion; 12 were referred for indications not related to head shape and found to have a normal study. Ultrasound scanning and interpretation of the lambdoid sutures was performed blinded to the CT reference standard. The lambdoid suture was read as patent or fused if a hypoechoic gap could or could not be seen between the hyperechoic calvarial bones, respectively. RESULTS: The mean sensitivity and specificity of ultrasound in distinguishing a patent from fused lambdoid suture by three blinded pediatric radiologists was 100% and 89%, respectively. CONCLUSIONS: Sonography of the lambdoid sutures shows excellent preliminary promise as a screening test of lambdoid sutural patency.

Cranial Sutures↗
PubMed1989

Two forms of glycosylated human prolactin have different pigeon crop sac-stimulating activities.

Two forms of glycosylated PRL (G-PRL) which differed in their binding properties to Concanavalin-A (Con-A) were isolated from human pituitary glands. One form, G1-hPRL, was only slightly retarded by Con-A; the other, G2-hPRL, was adsorbed by Con-A and could be eluted with methyl-D-manno-pyranoside, an indication of differing carbohydrate units in the two G-PRLs. Differences in type of glycosylation were also indicated by HPLC peptide mapping of tryptic digests of the two forms. The elution time for the tryptic peptide carrying the asparagine-linked carbohydrate unit varied for the two G-PRLs. The results point to the asparagine at position 31 as being the site of attachment of the carbohydrate. The carbohydrate structure influenced the crop sac-stimulating activity of the G-hPRLs. G1-hPRL had only about one fourth the activity of the reference standard (nonglycosylated ovine PRL, 35 IU/mg). The form that bound to Con-A, G2-hPRL, was equipotent to the reference standard. Because glycosylated forms have varying biological activities and are major components of circulating PRL, the physiological significance of serum concentrations of PRL measured by RIA will have to be reevaluated.

Amino Acid Sequence↗
PubMed2002

[Determination of heavy metal in Chinese herbs].

Microwave digestion system was used in digesting samples. Lead and cadmium were determined by graphite furnace atomic absorption spectrometry. Mercury was determined by cold vapor atomic absorption spectrometry. Standard reference material (NBS1570), spinach powder was used as analysis quality assurance in this method, and 264 Chinese herbs (23 species) and standard reference material were determined, and satisfactory results were obtained by using this method. Averages recovery of lead, cadmium and mercury is 95.0%, 97.5% and 99.2% respectively. Limit of detection (LOD) is 0.006 mg/kg, 0.208 microgram/kg and 0.026 microgram/kg respectively for lead, cadmium and mercury. Limit of quantity (LOQ) is 0.019 mg/kg, 0.694 microgram/kg and 0.087 microgram/kg respectively for lead, cadmium and mercury. This method is also suitable to determine lead, cadmium and mercury in food.

Cadmium↗
PubMed1988

[Muscle and fat indicators in boys of the upper socioeconomic strata of Caracas].

A sample of 271 boys, aged four, eight and 12 years, belonging to the upper socioeconomic strata of Caracas, was studied in order to test the sensibility and specificity of arm muscle and fat indicators, as evaluators of the muscle and fat tissues development, as well as of the nutritional status. Weight, height, arm circumference and triceps skinfold were measured following standardized techniques; muscle and fat areas were calculated from arm circumference and skinfold measurements. For statistical analysis, results were compared with North American reference standards, and correlation and regression analyses were performed. Nutritional assessment was performed using weight-for-age, height-for-age and weight-for-height, arm circumference and skinfold, plus the two derived areas. Malnourished children were identified using WHO guidelines in height and weight. Prevalences were compared and the sensibility, specificity and predictive values were studied. Malnourished children were analyzed individually. Arm circumference was the best predictor of nutritional status and triceps skinfold the worst predictor; muscle and fat areas were moderate predictors. On the average, four-year olds were smaller, lighter and much leaner than the reference, and eight and 12-year olds were taller, heavier and more muscular than the reference. Low fat was most prevalent in four-year olds, while high muscle increased with age and was highest at age 12, consistent with pubertal development. Obesity was most prevalent in eight-year olds. Twenty-eight per cent of the 50 children identified as malnourished in weight and height according to WHO, were normal in muscle and fat, and 66% of the 100 identified as malnourished in muscle and fat were normal according to WHO guidelines. Furthermore, 24% of children classified as overweight by weight-for-height were not obese but high in muscle. It is concluded that muscle and fat areas reflect muscle and fat components but are poor indicators of malnutrition, expressed in terms of weight and height. On the other hand, weight and height do not measure body composition. Weight-for-height should be used in combination with muscle and fat areas. National reference standards are needed and cut-off points should be revised, in order to maximize the efficiency and predictive values of these indicators.

Adipose Tissue↗
PubMedDate not supplied

Assessment of protein quality methodology for infant formulas.

Rat bioassay was used to assess the protein quality of powdered infant formulas and to evaluate the feasibility of using modified casein diets (containing the same source and level of fat and carbohydrate contributed by the infant formulas) as reference standards. Modification of the casein diet to match the milk-based formulas caused a significant reduction in weekly protein efficiency ratios (PER) and net protein ratios (NPR) at the third and fourth weeks. Modification of the casein diet to stimulate the soy-based formulas had no significant effect on NPR values; PER values were more varied. When PER and NPR values of the powdered milk-based formulas were expressed relative to the unmodified reference standard, the relative values were lower than when each matched reference was used. With few exceptions, the relative weekly PER values of the soy-based formulas were similar regardless of the standard used. The relative NPR values of the formulas had a pattern similar to the relative PER values. The data indicate that protein quality evaluation of infant formulas using rat bioassay warrants the use of matched casein reference diets for each type of formula.

Animals↗