Reference Values In Healthy Subjects Research Articles

Pupillary function in early multiple sclerosis

Autonomic pupillary function was assessed with pupillometry in 95 mildly or moderately disabled patients with multiple sclerosis (MS) and 81 healthy subjects. The parasympathetic pupillary function was measured as initial diameter (mm), time to minimum diameter (seconds), reflex amplitude (mm), relative reflex amplitude (%), and maximal constriction velocity (mm/seconds). To reflect the sympathetic pupillary function maximal redilatation velocity (mm/seconds), and time of 75% of redilatation (seconds) were measured. Of MS patients 85-99% were within the reference values of healthy subjects. In MS patients the effect of age was observed in the initial diameter, reflex amplitude, and time of 75% redilatation. There were no such age related effects in healthy subjects. In age adjusted analysis the initial diameter and time of 75% redilatation differed significantly from healthy controls. Autonomic pupillary functions were not associated with fatigue, visual defect, or bladder disturbance, as measured by Fatigue Severity Scale, Kurtzke's Functional System Scales, Expanded Disability Status Scale, or the Multiple Sclerosis Functional Composite. Our results suggest that both parasympathetic and sympathetic pupillary functions are disturbed already early in the course of MS. However, the disturbance is not severe at this stage of the disease. The dysfunction is age-dependent and thus possibly related to the dimished remyelination capacity of the central nervous system.

Biomarkers in the Exhaled Breath Condensate of Healthy Adults: Mapping the Path Towards Reference Values

The need for non-invasive assessment of airway inflammation is imperative, since inflammatory airway diseases, such as asthma and COPD, are characterized by variation in their clinical presentation throughout their course. Exhaled breath condensate (EBC) collection represents a rather appealing method that can be used to conveniently and noninvasively collect a wide range of volatile and non-volatile molecules from the respiratory tract, without affecting airway function or inflammation. Although promising, EBC is currently used only as a research tool, due to the lack of appropriate standardization and the absence of reference values. The large number of measurable biomarkers and the diversity of the used methodologies are some of the points that hamper its wide clinical application. This review focuses mainly on the presentation of normal values of the most widely studied EBC markers as reported by investigators that have used healthy subjects as controls or as a basic study population. These biomarkers include hydrogen peroxide, NO-related products, arachidonic acid metabolites and pH. From those biomarkers, the only one with established reference values in healthy subjects is EBC pH, whereas the majority of the rest need further refinement and standardization of the methodologies used. Different subpopulations and the effect of various factors on healthy subjects are also reported, in an effort to delineate future directions that may lead to the establishment of reference values.

Gastric emptying time of fluids and solids in healthy subjects determined by 13C breath tests: influence of age, sex and body mass index

Disturbance of gastric emptying leads to a variety of symptoms. Furthermore, gastric motility disorders might play a role in the pathophysiology of functional dyspepsia. In previous studies 13C breath tests were validated as non-invasive tools in the measurement of gastric emptying time. So far, reliable reference values of healthy subjects are missing and the impact of constitutional traits (age, sex, body mass index [BMI]) needs to be clarified. A study was conducted in 90 healthy individuals (45 men, 45 women) that assessed the correlation of parameters of gastric emptying (half gastric emptying time [T1/2] and time of fastest gastric emptying [T(lag)]) with age, sex and BMI for fluid and solid test meals by 13C breath tests. 100 mg of sodium acetate or sodium octanoate, respectively, were used as tracers. Breath probes were analyzed by non-dispersive infrared spectroscopy. The mean +/- SD of half gastric emptying time (T1/2) of a fluid test meal was determined to be 80.5 +/- 22.1 min and for T(lag) to be 40.3 +/- 10.2 min. However, the T1/2 and T(lag) of solid meals did not fit to normal distribution and thus median and percentiles were determined. The median time of T1/2 for solids was 127 min (25-75% percentiles: 112.0-168.3 min) and 81.5 min for T(lag) (25-75% percentiles: 65.5-102.0 min). No significant correlation was found between gastric emptying and age, sex or BMI. This is the first study to examine gastric emptying in an adequate number of healthy subjects by 13C breath tests. No significant correlation was found with age, sex and BMI. Although there is considerable standard deviation in gastric emptying time, these results may nevertheless serve as reference values for further studies.

Immune Restoration Under HAART in Patients Chronically Infected with HIV-1: Diversity of T, B, and NK Immune Responses

The aim of the study was to follow prospectively the humoral, cellular and innate immune responses under HAART and to verify if a functional restoration of the B lymphocytes could be evaluated by measuring the anti-HIV-1 IgG antibodies avidity index (AI). Eleven HIV-1 infected and immunosuppressed patients were included in the study. Viral load, naive and memory B-cells, CD4 and CD8 T-cells and NK-cells counts, and anti-HIV-1 IgG AI were determined during the follow-up (18 months). Ten patients were sustained responders under HAART and showed a quantitative restoration of the CD4 T-cell counts (+269 x 10(6)/L). The AI decreased for ten subjects (-11%, p = 0.006) but very slowly and continuously. A quantitative restoration of the humoral immune response began, mainly concerning the naive B-cells (+110 x 10(6)/L). Apart from one patient, the CD8 T-cell subset approached the reference values of healthy subjects either by decreasing or increasing their cell levels. No homogeneous evolution was described concerning the NK-cell subset, apart from trend towards increasing in patients with opportunistic infection (range, +58 to +291 x 10(6)/L). Our study, which evaluated simultaneously for the first time to our knowledge the cellular, humoral and innate immune responses showed that HAART induced a large diversity of immune restoration patterns in responder patients. However, the AI measure appears to be a weak marker to evaluate an immune restoration in chronic HIV-1 infected patients under HAART.

A pilot study of the feasibility of a set of instruments for disability assessments in persons with mild to moderate multiple sclerosis

The purpose of the study is to explore the feasibility of a set of eight instruments for describing aspects of function, activity, participation and health-related quality of life in people with mild to moderate disease severity in multiple sclerosis (MS). Data were collected from 24 persons with MS with mild to moderate disease severity 1.5–4.5 according to the Expanded Disability Status Scale (EDSS) using the Nine-hole Peg Test, Physiological Cost Index, Swedish Occupational Fatigue Inventory (SOFI), Montgomery–Asberg Depression Rating Scale, Symbol Digit Modalities Test, Free Recall and Recognition of 12 Random Words Test, Frenchay Activities Index, and Medical Outcomes Study 36-item Short Form Health Survey (SF-36). Exploration of feasibility included patients’ acceptance of the instruments, floor and ceiling effects, correlation of the included instruments with disease severity of MS as per EDSS and comparison of individual data with reference values of healthy subjects. Data could be collected using...

Urinary Markers of Adrenarche: Reference Values in Healthy Subjects, Aged 3-18 Years

Urinary Markers of Adrenarche: Reference Values in Healthy Subjects, Aged 3-18 Years

Urinary Markers of Adrenarche: Reference Values in Healthy Subjects, Aged 3–18 Years

Information on the urinary excretion of dehydroepiandrosterone (DHEA) and its direct metabolites is scarce for healthy subjects during growth. We used gas chromatography-mass spectrometry urinary steroid profiling to noninvasively study adrenarchal metabolome in 400 healthy subjects, aged 3-18 yr. Urinary 24-h excretion rates of DHEA did not increase significantly before age 7-8 yr. However, DHEA together with its 16alpha-hydroxylated downstream metabolites, 16alpha-hydroxy-DHEA and 3beta,16alpha,17beta-androstenetriol (DHEA&M), as well as the DHEA metabolite, 5-androstene-3beta,17beta-diol (ADIOL), and the sum of major urinary androgen metabolites (C19) rose consistently from the youngest to the oldest age group. The significant increases (P < 0.01) observed for 24-h excretion rates of C19, ADIOL, and DHEA&M were 2- to 4-fold in boys and girls between age 3 and 8 yr. DHEA&M, for example, rose from about 20 to 80 microg/d (P < 0.0001) during this period. Until the age of 16 yr, DHEA&M excretion also increased to nearly 1000 microg/d. Patterns of steroidogenic enzyme activities were assessed (from definite ratios of urinary steroid metabolites) for 21-hydroxylase, 3beta-hydroxysteroid dehydrogenase, 17beta-hydroxysteroid dehydrogenase, and 5alpha-reductase. Our results indicate for healthy boys and girls that adrenarche is a gradual process starting much earlier than hitherto believed. Efficient metabolism of DHEA, especially to 16-hydroxylated steroids, may explain the almost constant levels seen for this steroid until age 7-8 yr. The established reference values for DHEA, DHEA&M, ADIOL, C19 (including androsterone and etiocholanolone), and urinary parameters of steroidogenic enzyme activities could be useful to identify nutritional, environmental, and pathophysiological interrelations with the progressive maturational process of adrenarche. Our data may also be used as reference data for the diagnosis of steroid-related disorders.

Reference Values of Erythrocyte Sedimentation Rate of Adult Healthy Subjects

Background The purpose of this paper is to provide a scientific basic for a unified standard of the erythrocyte sedimentation rate (ESR) reference value of healthy subjects in China between the ages of 41 and 75 years. Methods ESR reference values of healthy subjects between 41 and 75 years of age were collected according to Wintrobe methods. The relationship between these healthy subjects' ESR reference values and altitude was tested in this paper. Results It was found that the ESR reference value of 41- to 75-year-old healthy subjects decreases when altitude gradually increases; the relationship is quite significant. Method of mathematical univariate regression analysis was used to deduce two regression equations: Y^ 1 = 14.89−0.00273 X ± 3.52, and Y^ 2 = 23.92−0.00423 X ± 5.34. Conclusions If the altitude value of a particular area of China is known, ESR reference value of healthy subjects (41–75 years) ) can be calculated by regression equations. Furthermore, in terms of altitude, China can be divided into the following three districts: Qingzang District; Central District, and Eastern District.

A new, fast and reliable radioimmunoassay of brain natriuretic peptide in human plasma. Reference values in healthy subjects and in patients with different diseases

A new, fast and reliable radioimmunoassay for measurement of brain natriuretic peptide (BNP) in human plasma has been developed and its application is reported in healthy subjects and in patients with congestive heart failure, chronic renal failure, liver cirrhosis and essential hypertension. The antibody was raised in rabbits, the tracer was made by the iodogen method and polyethylene glycol was used for separation of free and bound tracer. BNP was extracted from plasma using Sep-Pak C18 cartridges. The recovery of unlabelled BNP added to plasma was 77.5±6.2% (mean±SD). The detection limit in plasma was 0.55 pmol 1-1. No cross-reactivity existed with the natriuretic peptides ANP, CNP or urodilatin. In 124 healthy subjects the mean BNP was 1.8±1.0 pmol 1-1 (SD), range 0.6–5.5. BNP increased slightly with age, was higher in women than men and had no circadian rhythm. In eight patients with congestive heart failure the median BNP level was 30.5 pmol 1-1, range 3.9–65.3. In 14 patients with chronic renal failure the median BNP level was 50.5 pmol 1-1, range 10.9–219.8 before dialysis, and 38.0 pmol 1-1, range 9.4–180.0 immediately following dialysis. In 25 patients with liver cirrhosis the median BNP value was 7.8 pmol 1-1, range 1.2–43.1. There was no difference between patients with or without ascites. In 18 medically treated patients with essential hypertension the median BNP level was 5.0 pmol 1-1, range 1.2–45.5 pmol 1-1.

The magnesium loading test: reference values in healthy subjects.

The magnesium loading test is a useful tool in the diagnosis of magnesium deficiency. In order to establish a reference range in normal subjects, 88 healthy men and women aged between 18 and 66 years were given 30 mmol magnesium intravenously during eight hours as a loading test, urine was collected from start of infusion for 24 h for measurement of magnesium excretion. The magnesium mean retention was 6.3 +/- 10.3% of the loading dose, and the 0.025 and 0.975 fractiles were -19.5% and 27.5%, respectively. There was no significant difference between the sexes or in the different age groups studied. There was no correlation between the magnesium retention and serum magnesium or with basal urinary magnesium excretion. An excess excretion of magnesium was observed the postload day compared to baseline, but the excretion 24 and 48 h after the magnesium loading were closely correlated, suggesting that 24 h urinary sampling is sufficient. In order to examine the reproducibility of the test 23 of the subjects underwent two magnesium loading tests 4 weeks apart. The mean difference between two repeat magnesium loading tests was 2.0% with a SD of 8.1% and a 95% confidence interval of -1.6-5.5%. Normal saline did not affect baseline magnesium excretion. Concomitant administration of ethanol or physical exercise caused greater variation in magnesium excretion, whereas furosemide was without effect. The 8 h magnesium loading test with 24 h urine sampling seems to be fairly reproducible, is adequate for clinical use, but the normal range is wide.

Turns-amplitude analysis of the electromyographic recruitment pattern disregarding force measurement. I. Method and reference values in healthy subjects.

We used turns-amplitude analysis to characterize the EMG recruitment pattern disregarding force measurement. The electrical muscle pattern of the brachial biceps (BB), abductor pollicis brevis (APB), medial vastus (MV), and anterior tibial (AT) muscles was analyzed during progressive increase in force from rest to maximum using the mean amplitude as an indicator of the force of the muscle. The following parameters were obtained on-line: the maximal ratio of turns to mean amplitude (peak-ratio, PR), the mean amplitude, and the number of time intervals (TI) between turns at PR and at near maximum force (NMF). The highest PR values were obtained in BB, the lowest in MV. Analysis of the distribution of the TI between turns at different degrees of voluntary contraction showed fewer spikes with short duration and small amplitude at high force compared with low force.

Serum CK-BB as a tumor marker in patients with carcinoma confirmed histologically

We determined serum CK-BB mass concentration using a specific RIA method, in 267 patients with carcinoma confirmed histologically distributed as follows: 46 prostatic adenocarcinoma, 52 lung neoplasies, 70 colon carcinoma, 52 breast carcinoma and 41 gastric carcinoma; and also in 135 patients with histologically proved non-neoplastic diseases distributed as follows: 28 prostatic hyperplasy, 31 lung tuberculosis, 29 inflammatory bowel disease, 27 fibrocystic mastopathy and 20 gastroduodenal ulcer. Reference values in healthy subjects (n = 360) were 5.46 +/- 2.68 (SD) ng/ml. We found that serum CK-BB mass concentration is not a specific tumor marker but it is a valuable indicator of responsing to therapy and metastatic widespread. However, in prostatic carcinoma--prevalence 0.25, predictive positive value (PPV) 0.51 and predictive negative value (PNV) 0.88--and breast carcinoma--prevalence 0.32, PPV 0.60 and PNV 0.87--serum CK-BB can be used as a tumor marker. Only 12 over 268 patients with different neoplastic disease (4.47%) showed detectable serum CK-BB catalytic concentrations.

Serum CK-BB as a tumor marker in patients with carcinoma confirmed histologically

We determined serum CK-BB mass concentration using a specific RIA method, in 267 patients with carcinoma confirmed histologically distributed as follows: 46 prostatic adenocarcinoma, 52 lung neoplasies, 70 colon carcinoma, 52 breast carcinoma and 41 gastric carcinoma; and also in 135 patients with histologically proved non-neoplastic diseases distributed as follows: 28 prostatic hyperplasy, 31 lung tuberculosis, 29 inflammatory bowel disease, 27 fibrocystic mastopathy and 20 gastroduodenal ulcer. Reference values in healthy subjects ( n = 360) were 5.46 ± 2.68 (SD) ng/ml. We found that serum CK-BB mass concentration is not a specific tumor marker but it is a valuable indicator of responsing to therapy and metastatic widespread. However, in prostatic carcinoma—prevalence 0.25, predictive positive value (PPV) 0.51 and predictive negative value (PNV) 0.88—and breast carcinoma—prevalence 0.32, PPV 0.60 and PNV 0.87—serum CK-BB can be used as a tumor marker. Only 12 over 268 patients with different neoplastic disease (4.47%) showed detectable serum CK-BB catalytic concentrations.