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PubMedDate not supplied

[Reference values for maximal midexpiratory flow in black females].

The aim of this publication is to contribute to the establishment of reference values for the forced expiratory flow between 25 and 75% of the vital capacity (FEF25-75) among black females in West Africa. 316 of them, aged between 10 and 70 years, were submitted to this test. They were considered free from cardiopulmonary disease after a questionnaire and clinical examination. FEF25-75 in absolute value was lower than in the white Euro-americans. It increased up to 18-19 years of age, then decreased steadily thereafter. The main equations of regression for the FEF25-75 (l X s-1) were: 10-18 years, 0.177A + 1.058 and 0.157A + 0.826H + 0.005; 19-70 years, -0.028A + 4.211 and -0.025A + 2.206H + 0.512, (where A is the age in years and H the height in metres). The results are compared with the reference values published in Black Africa, Europe and the United States.

Adolescent↗
PubMed2005

Reference values and repeatability of inspiratory capacity for men and women aged 65-85.

The inspiratory capacity (IC) has recently gained importance because it may signal the occurrence of dynamic hyperinflation at rest or during exercise by reflecting changes in the end expiratory lung volume (EELV). However, reliable predicted values for IC are not currently available. The aim of the study was to generate predictive equations for reference values of IC in adults aged 65-85 living in Italy and to determine its limits of the within test-session repeatability. From the control group (n=429) of the SARA study data base, 241 (161 females) never smoked, non-obese (BMI<30 kg/m2) healthy subjects aged 65-85 who were able to correctly perform at least two manoeuvres of IC were selected. A model that incorporated age, height and body mass index as significant predictors in either sexes produced predicting equations for IC with a coefficient of determination of r2=.36 and .34 for females and males, respectively. Ninety per cent of all the subjects were able to keep the second highest IC within 200 ml (<9%) from the best IC. No significant gender difference was found for IC repeatability. We provided the equations for deriving reliable IC reference values that can be applied in the elderly people living in southern Europe. In this population IC showed limits of the within-session repeatability similar to those accepted for other spirometric indices such as FEV1 and FVC.

Aged↗
PubMed2002

Measurements of interrupter resistance: reference values for children 3-13 yrs of age.

The interrupter technique is a convenient and sensitive technique for studying airway function in subjects who cannot actively participate in (forced) ventilatory function tests. Reference values for preschool children exist but are lacking for children >7 yrs. Reference values were obtained for expiratory interrupter resistance (R(int,e)) in 208 healthy Dutch Caucasian children 3-13 yrs of age. A curvilinear relationship between R(int,e) and height was observed, similar to published airways resistance data measured by plethysmography. No significant differences in cross-sectional trend or level of R(int,e) were observed according to sex. It was found that Z-scores could be used to express individual R(int,e) values and to describe intra- and interindividual differences based on the reference equation: 10logR(int,e)=0.645-0.00668x standing height (cm) kPa x L(-1) x s(-1) and residual SD (0.093 kPa x L(-1) x s(-1)). Expiratory interrupter resistance provides a tool for clinical and epidemiological assessment of airway function in a large age range.

Adolescent↗
PubMed2005

Assessment of reference values for selected elements in a healthy urban population.

Reference values for 26 elements, namely Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, Tl, V, W, Zn and Zr are proposed in serum and blood of 110 healthy adults of the urban area of Rome. They were included in the study on the basis of strict criteria of eligibility and exclusion. With the exception of Ba, Bi, Co, Cr, Ni, Sb, Sn Tl in serum, and Bi, Hg, Si, V and W in whole blood, experimental data for each all the other analytes were found to approach a normal distribution. The estimated 5-95% references ranges (in ng ml(-1)) were reported. For several elements the reference ranges observed overlapped information available in the literature. Gender, age, body mass index, smoking habits and alcohol consume were used as grouping variables. Mutual associations were observed for several elements, as follows: Be, Ca, Co, Cr, Cu, Li, Mo, Pb and Zn with sex; Ca, Pb and Si with age (< and > 45 years); Co, Cr, Mo, Sb and Tl with body mass index; Cd and Pb with smoking habit; Cr and Pb with alcohol consume.

Adult↗
PubMed2006

Anthropometric body fat composition reference values in Spanish adolescents. The AVENA Study.

OBJECTIVE: To determine reference values for body mass index (BMI), sum of six skinfolds (sigma6 skinfolds) and body fat percentage (BF%) in Spanish adolescents aged 13-18 years, included in the AVENA Study (Alimentación y Valoración del Estado Nutricional en Adolescentes: Food and Assessment of the Nutritional Status of Adolescents). DESIGN: Multicentre cross-sectional study. SETTING: Representative sample of Spanish adolescents. SUBJECTS: The population was selected by means of a multiplestep, simple random sampling. The final number of subjects included in the AVENA Study was 2859 adolescents; 2160 adolescents had a complete set of anthropometric measurements and were then included in this study (1109 males and 1051 females). INTERVENTIONS: Weight, height and six skinfold thicknesses were measured. As indices of total adiposity, we calculated BMI, summation sigma6 skinfolds and BF% with the formulas described by Slaughter et al. RESULTS: Sigma6 skinfolds and BF% in each age group were significantly higher in females than in males. In males, age showed a significant effect for BMI, sigma6 skinfolds and BF%; however, in females, the effect was only significant for BF%. The percentile distribution was more disperse towards higher sigma6 skinfolds and BF% values in males when compared with females. CONCLUSIONS: The presented percentile values will help us to classify adolescents in comparison with a well-established reference population, and to estimate the proportion of adolescents with high or low adiposity amounts. SPONSORSHIP: The AVENA-Study was supported by the Spanish Ministry of Health (FIS 00/0015), and grants from Panrico SA, Madaus SA and Procter and Gamble SA. This study was also supported by Instituto de Salud Carlos III (Spain), RCESP (C03/09) and Spanish Ministry of Education (AP2003-2128).

Adipose Tissue↗
PubMed2002

Assessment of reference values for mercury in urine: the results of an Italian polycentric study.

The results of a polycentric study to assess the reference values of urinary mercury (U-Hg) in four Italian cities are presented. A total of 383 subjects were selected on the basis of standardised criteria by a questionnaire on personal habits, lifestyle, occupational or non-occupational exposure to Hg, medical history, number and area of dental amalgams. U-Hg was determined by hydride generation atomic absorption method (HG-AAS), with a detection limit of 0.5 microg/l and by flow injection (FI) inductively coupled plasma mass spectrometry (ICP-MS), with a detection limit of 0.03 microg/l. The median value of U-Hg, determined by HG-AAS, was 0.78 microg/g creatinine (0.75 for males and 0.83 for females), with 5 degrees and 95 degrees percentiles, respectively, of 0.17 and 3.66 microg/g creatinine. When determined by FI ICP-MS, the median value was 0.79 microg/g creatinine (0.77 for males and 0.79 for females) with 5 degrees and 95 degrees percentiles of, respectively, 0.12 and 5.02 microg/g creatinine. Among the independent variables, city of origin, area of dental amalgams, fish intake and tobacco smoking significantly influenced the U-Hg levels. The U-Hg reference values from this survey are lower than those from other recent investigations, probably due to characteristics and selection of the examined individuals and to the strict control of pre-analytical and analytical factors of variability.

Adult↗
PubMedDate not supplied

Reference values for acoustic rhinometry in subjects without nasal symptoms.

Reference values for acoustic rhinometry are presented from 334 individuals without nasal symptoms between 4 years and 61 years old. There was a significant correlation between the minimal cross-sectional area (MCA) and nasal volume. Although the reproducibility of the method was good, the MCA varied widely. MCA correlated weakly to weight, height, age, and body mass index. Our data suggest that acoustic rhinometry is valuable for inter-individual comparisons.

Acoustics↗
PubMed1998

Prostate-specific antigen (PSA), PSA density and age-adjusted PSA reference values in screening for prostate cancer--a study of a randomly selected population of 2,400 men.

Prostate cancer screening with DRE, TRUS, and PSA testing was offered to 2,400 randomly selected men 55-70 years old. Among 1,782 examined, 65 (3.6%) men with prostate cancer were diagnosed. The PSA results were correlated to the diagnosis, the men's age, and the prostate volume. Least square regression analysis was used to calculate the 95% upper confidence intervals for PSA in each year of age in men without prostate cancer. The PPV was calculated for: (i) PSA > 4 ng/ml, (ii) PSAD > 0.15, (iii) PSAD > 0.20 and (iv) age-adjusted PSA reference values. A significant correlation was found between PSA and prostate volume, between PSA and age, and between the prostate volume and age. The calculated annual growth of the prostate was 1.6% and the annual increase in PSA was 2.4%. The age-adjusted upper PSA reference values for the three age categories studied (55-59, 60-64 and 65-70 years) were 5.2, 5.8, and 6.7 ng/ml, respectively. The PPVs for PSA > 4 ng/ml, PSAD > 0.15, PSAD > 0.20, and the age-adjusted PSA reference values were 17%, 14%, 22%, and 27%, respectively. Age-adjusted PSA or PSAD may increase the PPV compared to PSA > 4 ng/ml. The detection rate is, however, inadequate. A PSA cut-off at 4 ng/ml could therefore be maintained in men 55-70 years old. The median PSA values and median prostate volumes calculated for men with benign findings may serve as a reference in future studies.

Age Factors↗
PubMed2003

[Reference values in pregnancy].

The body of pregnant women demonstrates in many ways different functions compared to non pregnant women. In order to assess lab results of antenatal tests the knowledge of physiologic and pathophysiologic changes are essential. This article reviews the state of the art in terms of reference values during pregnancy enriched with own results. Of special value for the practitioner are such reference values and curves for the circulatory system, kidney function, hematologic changes, plasma components and weight gain.

Adult↗
PubMed1987

Patterns of porphyrin excretion in feces as determined by liquid chromatography; reference values and the effect of flora suppression.

While determining reference values for porphyrins in feces as measured by liquid chromatography, we observed strong fluctuations in fecal porphyrin contents. To explain these fluctuations, we selectively suppressed the intestinal flora of healthy persons. Suppression of aerobic flora had no effect on fecal porphyrin excretions, whereas suppression of anaerobic flora completely inhibited the transformation of protoporphyrin to pempto- and deuteroporphyrin for as long as five days after stopping medication. During this latter, the conversion to mesoporphyrin was clearly increased in one person and in others partly affected or decreased. During complete suppression of flora for prolonged periods, the production of proto- and coproporphyrins was decreased and deutero-, pempto-, and mesoporphyrins were absent. We conclude that the nature of fecal porphyrins is mostly affected by action of anaerobic bacteria, different kinds of bacteria having different effects. Some, like aerobic Gram-negative bacteria, have little or no effect on porphyrins; some cause production of mesoporphyrin; some promote a conversion to pempto- and deuteroporphyrin; and some mainly cause production of copro- and protoporphyrin. We give examples in which normal to slightly increased excretions of fecal porphyrin do not exclude a diagnosis of porphyria, and relatively high concentrations do not confirm one.

Bacteria↗
PubMed2002

Plasma biochemistry reference values of wild bonnethead sharks, Sphyrna tiburo.

BACKGROUND: Elasmobranchs (sharks, skates, and rays) are of commercial, sport, research, and exhibit importance, however, blood chemistry reference values have been determined for few of these species. OBJECTIVE: The purpose of this study was to establish plasma biochemistry and PCV reference values for wild bonnethead sharks (Sphyrna tiburo). METHODS: Heparinized blood samples were collected from 24 bonnethead sharks at the time of capture in trawl nets off the coast of South Carolina and Georgia. Weight, length, PCV, total solids (TS, by refractometry), and plasma biochemical analyses were done using standard techniques. Wilcoxon rank-sum and Kendall tau b tests were used to compare values by animal size, boat and sex; 1-way ANOVA was used to compare TS and total protein (TP) concentrations. RESULTS: Median (quartile; minimum-maximum) values were as follows: PCV 22% (22%, 26%; 17-28%), TS 6.3 (6.0, 6.8; 5.8-7.5) g/dL, total protein 2.9 (2.7, 3.4; 2.2-4.3) g/dL, albumin 0.4 (0.4, 0.4; 0.3-0.5) g/dL, globulins 2.6 (2.3, 3.0;1.9-3.8) g/dL, sodium 282 (279, 285;273-292) mmol/L, potassium 7.3 (6.4, 7.9; 5.7-9.2) mmol/L, chloride 290 (285, 296; 277-304) mmol/L, total CO2 3 (2, 4; 0-5) mmol/L, calcium 16.8 (16.2, 17.4;15.8-18.2) mg/dL, phosphorus 8.8 (7.5, 10.0; 5.9-12.7) mg/dL, urea nitrogen 1004 (986, 1028; 944-1068) mg/dL, creatinine <0.1 mg/dL, glucose 184 (165, 191; 155-218) mg/dL, aspartate aminotransferase 42 (33, 66; 15-132) U/L, lactate dehydrogenase <5 U/L, creatine kinase 82 (47, 233; 18-725) U/L, and osmolality 1094 (1078, 1111; 1056-1139) mOsm/kg. No differences based on sex were detected. TS and TP values were related by the fitted line TS = (1.006 X TP) + 3.318. CONCLUSION: Values reported here will be useful for evaluating the health status of bonnetheads in wild and captive research conditions and in exhibits.

Animals↗
PubMed2000

The use of insulin-like growth factor 1 reference values for the diagnosis of growth hormone deficiency in prepubertal children.

OBJECTIVE: This study was done to determine whether the use of reference values obtained in children with idiopathic short stature (ISS) improved the clinical value of serum insulin-like growth factor I (IGF-1) as a tool for diagnosing GH deficiency (GHD) in prepubertal children. PATIENTS AND METHODS: Serum IGF-1 was measured with a new IRMA kit (IGFI-RIA CT, Cis Bio, Gif sur Yvette, France) in 168 prepubertal normal children and in prepubertal children with ISS (n = 68), organic GHD due to a craniopharyngioma (oGHD, n = 15) and permanent idiopathic GHD (iGHD, n = 28). RESULTS: IGF-1 was lower (P < 0.001) in iGHD than in either ISS or oGHD and was below the fifth percentile of the normal range in 29/68 ISS (43%), 8/15 oGHD (53%) and 28/28 (100%) iGHD patients. Three oGHD (20%) and two iGHD (7%) patients had a serum IGF-1 below the fifth percentile of the normal group but above the fifth percentile of the ISS group. Thus, a serum IGF-1 below the fifth percentile of the normal group distinguished between normal children and iGHD with 100% sensitivity, between normal and oGHD with 53% sensitivity and between normal and all GHD (idiopathic + organic) with 84% sensitivity; the overall specificity was only 57%. Conversely, a serum IGF-1 below the fifth percentile of the ISS population distinguished between ISS and iGHD with 93% sensitivity, between ISS and oGHD with 33% sensitivity and between ISS and all GHD with 72% sensitivity; the overall specificity was then 95%. CONCLUSIONS: A serum IGF-1 within the normal range virtually excludes idiopathic GHD but does not rule out organic GHD, whereas an IGF-1 below the ISS range is strongly in favour of GHD, after exclusion of poor nutritional status and/or liver disease. An IGF-1 below the normal range but in the idiopathic short stature range gives no definitive conclusion even when it is associated with a low GH peak. Thus, whereas reference values obtained in normal children must be used to interpret serum IGF-1 in short prepubertal children, reference data obtained in idiopathic short stature children should also be taken into account.

Child↗
PubMed2005

Establishment of reference values for endocrine tests. Part IV: Adrenal insufficiency.

BACKGROUND: The short Synacthen test, the overnight metyrapone test and the insulin tolerance test are frequently used in the evaluation of patients suspected of adrenal insufficiency. in the present study, we established reference values for these diagnostic tests, as well as for baseline morning plasma cortisol and adrenocorticotrophic hormone (ACTH). METHODS: We studied 50 subjects recruited from the general population, equally distributed according to sex and age between 20 and 69 years. A short ACTH stimulation test (250 microg Synacthen iv), an overnight metyrapone test (2.0, 2.5, or 3.0 g given orally depending on body weight at 23.30 hours) and an insulin tolerance test (0.15 U/kg actrapid iv) were performed. Reference intervals are given as the means +/- 2SD of observed hormone concentrations after logarithmic transformation. RESULTS: The following reference values were established: 09.00 hr plasma cortisol 150 to 802 nmol/l, 09.00 hr plasma ACTH 8 to 93 ng/l, peak plasma cortisol after Synacthen 591 to 1,113 nmol/l, peak plasma cortisol after insulin-induced hypoglycaemia 557 to 1,015 nmol/l, and plasma 11-deoxycortisol after metyrapone 197 to 759 nmol/l. CONCLUSION: We established reference values for diagnostic tests that are useful in the evaluation of patients suspected of primary or secondary/tertiary adrenal insufficiency.

Adrenal Cortex Function Tests↗
PubMed2005

Hematologic and lymphocyte immunophenotypic reference values for normal rhesus monkey (Macaca mulatta) umbilical cord blood; gravidity may play a role in study design.

Hematology and flow cytometry reference values for rhesus umbilical cord blood (UCB) were established in 17 healthy infant rhesus monkeys delivered by elective cesarean section 10 days preterm. The infants were born to age matched, singly caged primigravid or secundigravid dams. The hematology and flow cytometry values were determined by automated cell counter and by FACS. No significant differences were observed with respect to infant gender. With respect to gravida, the primigravid infants had a significantly higher percentage (P= 0.05) of CD20(+) B lymphocytes in UCB. These results provide useful reference values for future studies of maternal - fetal disease transmission, vaccine and drug evaluation in non-human primate pregnancy, as well as fetal programming and immune modulation, gene therapy and the use of UCB as a source of stem cells for research and transplantation. Importantly, our results suggest that maternal gravidity may be an important variable to consider.

Animals↗
PubMed1997

Reference values for the trace elements copper, manganese, selenium, and zinc in the serum/plasma of children, adolescents, and adults.

Up to now few plasma or serum reference or serum reference values have been available for the assessment of the essential trace element supply status in different age groups covering the whole range of life range. In the present investigation, the concentrations of copper, manganese, selenium, and zinc were determined in the serum of 137 healthy children and in the plasma of 68 blood-donors. The age distribution within these groups ranged from 1 month to 18 years and from 22 to 75 years. The determinations were carried out directly by means of electrothermal atomic absorption spectrophotometry with Zeeman background compensation. The adult plasma reference values (mean +/- 2 SD) were 1.65 +/- 8.6 mumol/1 for copper, 14.3 +/- 11.4 nmol/1 for manganese, 0.80 +/- 0.36 mumol/1 for selenium, and 16.6 +/- mumol/1 for zinc. No correlation between concentration of elements and sex could be established. In the child and adolescent group, the manganese levels exhibited an age-dependent linear decrease (54% of the starting value, slope 0.92, r = 0.4, p < 0.001), the copper and the selenium concentrations, respectively, exhibited an exponential increase (107%, r = 0.59 and 174%, r = 0.61), with the highest value in the age group of 6 to 10 years. Reference ranges are established for 9 different age groups. The results reflect the known physiological data on the trace element content in the tissue of children and their diet. The present study is an important pre-requisite for diagnosis and therapy of trace element deficiencies in all age groups.

Adolescent↗
PubMedDate not supplied

Reference values and modelling of lung function development as a transcendent function of age, body height and mass.

We present new lung function reference values based on an investigation of 1024 healthy subjects aged 6-81 years. The dependent variables, i.e. VC, FEV1, RV, FRC, TLC, PEF, MEF50 and MEF25 are expressed as transcendent functions of age, body height and mass. A single equation covers the age range from 6 to 81 years and reflects certain phenomena such as growth, maturation, ageing, sex differences and the undermass-overmass effect. This allows a more accurate determination of individualized reference values and normal limits.

Adolescent↗
PubMedDate not supplied

[Incremental stress test: comparison between protocols and cardiorespiratory reference values in healthy workers].

The aim of this study was double: to compare two different incremental stress protocols and to obtain reference values for a standardised exercise test in healthy workers. Firstly, eighty healthy male workers, 40 coal miners and 40 hospital workers, aged 19-54, performed in 2 different days 2 cycle ergometer tests up to exhaustion, increasing the work load respectively by 30 watts every 3 minutes (protocol A) and by 30 watts each minute (protocol B). Ventilatory and gas exchange measurements were done by a breath-by-breath apparatus equipped with a turbine and fast gas analysers for O2 and CO2. For each test the ventilatory anaerobic threshold (VAT) was blindly determined as oxygen uptake (V'O2 VAT) using standardised gas exchange and ventilatory indices (V'CO2, V'E, V'E/V'O2) that were found giving comparable results with those derived from the blood lactacte curve. Significant differences were observed between the two protocols only concerning the average work load at exhaustion and at the VAT: the highest being with the protocol B. Conversely, either the maximal oxygen uptake (V'O2 max) and the V'O2 VAT were comparable between protocols, as well as the other cardio-respiratory parameters were at these exercise levels. Oxygen uptake and heart rate increased in average linearly with the work load with very similar slopes in both protocols. Comparable results between protocols were found also as what concerns the slopes of the other physiological variables (V'E, V'CO2) analysed against the V'O2, particularly for exercise levels lower or equal to the individual VAT. Thus, these results suggest a very good comparability between the two protocols, concerning both the levels of maximal and sub-maximal aerobic capacity (V'O2 max, V'O2 VAT) and the cardio-respiratory pattern related to the oxygen uptake. Reference values for the 30 watts/3 minutes cycle ergometer stress test were achieved in other 320 healthy Sardinian workers concerning both the maximal (V'O2 max) and sub-maximal (V'O2 VAT) aerobic capacity and the range of normality for the cardio-respiratory pattern during the test, particularly for completely aerobic work loads, namely work loads not above the V'O2 VAT. These prediction equations can be useful for the evaluation of working capacity of workers employed in manual jobs characterised by moderate-to-high dynamic energy expenditure.

Adult↗