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At least 1,459 records · Page 81Linked to original sources
PubMed1999

Urinary excretion of albumin in adolescents with type 1 diabetes: persistent versus intermittent microalbuminuria and relationship to duration of diabetes, sex, and metabolic control.

OBJECTIVE: Urinary excretion of albumin is a marker for incipient diabetic nephropathy in adults. The intra-individual variability, as well as the relationship to duration of diabetes, onset of the disease, and long-term metabolic control, have not been evaluated in a large sample of pediatric patients. RESEARCH DESIGN AND METHODS: A total of 5,722 nocturnal urinary albumin excretion rates were determined in 447 children, adolescents, and young adults with type 1 diabetes, comprising 1,821 years of observation. Excretion rates were related to duration of diabetes, age at onset of diabetes, sex, blood pressure, and metabolic control. RESULTS: Based on repeated measurements in individual patients, the positive predictive value of one sample was 76%, the negative 99.5%. After a duration of diabetes of 11 years, 5% of patients displayed persistent microalbuminuria (10% after 13 years). The duration of diabetes until persistent microalbuminuria was identical for patients with prepubertal or pubertal onset of diabetes. In addition to duration, female sex (P < 0.03) and insufficient long-term metabolic control (P < 0.03) contributed significantly and independently to urinary albumin excretion. CONCLUSIONS: Determination of urinary albumin excretion rate is useful in pediatric patients. Female subjects with a long duration of diabetes and insufficient metabolic control are especially at risk for microalbuminuria. Even if persistent microalbuminuria usually becomes evident in patients aged > 11 years, the prepubertal duration of diabetes contributes equally to this risk. Good metabolic control therefore should be aspired to from the onset of diabetes.

Adolescent↗
PubMed1989

A diagnostic programme for quantitative analysis of proteinuria.

A spectrum of quantitative methods was adapted to the Kone Specific Analyser for the purpose of recognizing, quantifying and differentiating various forms of proteinuria. Total protein, IgG, albumin and alpha 1-microglobulin (measured by turbidimetry), N-acetyl-beta-D-glucosaminidase activity and creatinine (measured photometrically), were measured in undiluted urine; in addition alpha 1-microglobulin was measured in serum. Within and between run precision, accuracy and linearity of the turbidimetric methods were in good agreement with nephelometric procedures. All turbidimetric methods exhibited a correlation coefficient r greater than 0.98 when compared with the radial immunodiffusion procedure as reference method. Total protein measured turbidimetrically with the Kone Specific Analyser was in good agreement with the manual biuret procedure. The low detection limits and linearities allowed quantification of urine analytes from the lower range of normals up to ten times the upper limit of normals. The measured analytes exhibited stability in urine at pH 4-8 over at least seven days at 4-6 degrees C and -20 degrees C. Only IgG showed a significant loss (up to 30 percent), when measured after storage at -20 degrees C. Quantities per mol creatinine showed significantly lower intra-individual and inter-individual variability than quantities per liter. In 31 normal persons, the intraindividual variation was lowest for N-acetyl-beta-D-glucosaminidase activity (13%) and highest for total protein (33%), when measured in the second morning urine on 5 consecutive days. When related to creatinine, results obtained in the second morning urine showed no significant differences from those in 24 h urine, except for alpha 1-microglobulin which gave lower values in 24 h urines. The upper normal limits, calculated as the 95% ranges, were determined from 154 urines of 31 individuals. Nearly all analytes showed an asymmetric distribution. Because of a wide tailing of the upper limit, preliminary upper normal limits were set above this range: (table; see text) Application of the newly adapted programme to unselected urines sent for urine analysis revealed a threefold increase in the proportion of results outside the normal ranges, compared with the routinely used protein test strip procedure. All additional positive urines exhibited either signs of glomerular or tubular proteinuria. Determination of albumin or N-acetyl-beta-D-glucosaminidase excretion was sufficient to detect these additional cases.

Diagnosis, Differential↗
PubMed1992

Stability of the circadian alteration in lung function in asthma.

Although studies on pharmacologic interventions for nocturnal asthma are increasing, information about the long-term stability of circadian spirometric changes or bronchial responsiveness is not known. This study was undertaken to evaluate these variables in 10 patients with asthma measured quarterly during a 1-year period. We have found that the overnight decrease in peak expiratory flow rate measurements is stable (mean range, 13.8% to 16.4%) during the year, as are the quarterly 4 PM (1600-hour) and 4 AM (0400-hour) FEV1 values. The 4 PM provocative concentration of methacholine that produced a 20% fall in FEV1 (PC20) (range of geometric mean, 0.213 to 0.359 mg/ml) and the 4 AM PC20 (range, 0.057 to 0.152 mg/ml) for the group were also relatively stable. Individual variation was higher for the PC20 values than for the FEV1. We concluded that during a 1-year period, without acute respiratory events, (1) the overnight decrement in peak expiratory flow rate and the 4 AM and 4 PM FEV1 values were constant and (2) bronchial responsiveness demonstrated some individual variability, but for the group, it remained stable.

Adult↗
PubMed1991

Enzyme activities of urinary alanine aminopeptidase (AAP) and N-acetyl-beta-D-glucosaminidase (NAG) in healthy dogs.

The activity of the urinary enzymes alanine aminopeptidase (AAP; EC 3.4.11.2) and N-acetyl-beta-D-glucosaminidase (NAG; EC 3.2.1.30) was measured after eliminating distorting factors in ten healthy dogs on three consecutive days in order to determine inter- and intra-individual variability. All the animals were being housed and fed in the same way. The urine (2nd morning urine) was collected between 8:30 and 10:00 a.m. by means of ultrasound-controlled cystocentesis. Our comparative measurements of native and gel-filtered urine showed an increase in enzyme activity in all of the samples in the case of AAP and in most of the samples in the case of NAG, thus proving the existence in the dog of AAP and NAG urinary enzyme inhibitors. The large inter- and intra-individual AAP and NAG fluctuation ranges were reduced considerably by relating enzyme activity to urine creatinine concentration. The provisional upper limit of the AAP reference range is 6.3 U/g creatinine (90% percentile), that of NAG 6.2 U/g creatinine (90% percentile). The AAP and NAG enzyme activities remained constant in gel-filtered samples kept at 4 degrees C for at least 5 days, in those kept at -18 degrees C for at least 4 weeks.

Acetylglucosaminidase↗
PubMed1979

Do 16-week-old infants anticipate stimulus offsets?

Twenty alert 16-week-old infants were presented with 20-sec tones at variable intertrial intervals for 10 trials while beat-by-beat heart rate responses were recorded to assess response at offset as well as onset of each stimulus. Consistent with past research, onsets elicited deceleratory responses which habituated and showed some evidence of dishabituation with a change in stimulus frequency on the last 2 trials. Offsets also elicited significant deceleratory responses overall, but inspection of pre-offset heart rate suggested that deceleration in anticipation of the offset event appeared after a few stimulus repetitions and increased in magnitude over trials. However, individual variability was considerable and although the anticipatory response was significant averaged over all trials, the apparent increase over trials did not reach statistical significance. The evidence clearly indicates infants quickly process and act upon temporal information in a stimulus.

Child Development↗
PubMed2001

Age-related changes in motor control during articulator visuomotor tracking.

The present study provides normative data on changes in visuomotor control of the oral-facial system across the lifespan. Control of the lower lip, jaw, and larynx (i.e., fundamental frequency) was examined using a nonspeech visuomotor tracking (VMT) task, where subjects move the articulator of interest to track a moving target on an oscilloscope screen. This task examines articulator motor control during movements that are similar to speech but that do not impose linguistic units or the demands of coordinating multiple structures. Accuracy and within- and between-subject variability in tracking performance were measured by cross correlation, gain ratio, phase shift, and target-tracker amplitude difference. Cross-correlation analyses indicated that performance of children (aged 8;2 to 17;0 [years;months]) and older adults (aged 45;1 to 84;3) is poorer than that of younger adults (aged 17;1 to 45;0). Accuracy of movement amplitude tended to increase during development and decline with aging, whereas age did not appear to influence accuracy of temporal parameters in lip and jaw tracking. In contrast, age tended to influence individual variability in temporal but not amplitude parameters. Differences were noted between articulators. The data complement previous studies that considered accuracy and variability of articulator movement during speech. The VMT method and the data provided may be applied to assessment of impairments in the motor speech system and to differential diagnosis of motor speech versus linguistically based disorders.

Adolescent↗
PubMed1995

Multiple organ dysfunction score: a reliable descriptor of a complex clinical outcome.

OBJECTIVE: To develop an objective scale to measure the severity of the multiple organ dysfunction syndrome as an outcome in critical illness. DESIGN: Systematic literature review; prospective cohort study. SETTING: Surgical intensive care unit (ICU) of a tertiary-level teaching hospital. PATIENTS: All patients (n = 692) admitted for > 24 hrs between May 1988 and March 1990. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Computerized database review of MEDLINE identified clinical studies of multiple organ failure that were published between 1969 and 1993. Variables from these studies were evaluated for construct and content validity to identify optimal descriptors of organ dysfunction. Clinical and laboratory data were collected daily to evaluate the performance of these variables individually and in aggregate as an organ dysfunction score. Seven systems defined the multiple organ dysfunction syndrome in more than half of the 30 published reports reviewed. Descriptors meeting criteria for construct and content validity could be identified for five of these seven systems: a) the respiratory system (Po2/FIO2 ratio); b) the renal system (serum creatinine concentration); c) the hepatic system (serum bilirubin concentration); d) the hematologic system (platelet count); and e) the central nervous system (Glasgow Coma Scale). In the absence of an adequate descriptor of cardiovascular dysfunction, we developed a new variable, the pressure-adjusted heart rate, which is calculated as the product of the heart rate and the ratio of central venous pressure to mean arterial pressure. These candidate descriptors of organ dysfunction were then evaluated for criterion validity (ICU mortality rate) using the clinical database. From the first half of the database (the development set), intervals for the most abnormal value of each variable were constructed on a scale from 0 to 4 so that a value of 0 represented essentially normal function and was associated with an ICU mortality rate of < 5%, whereas a value of 4 represented marked functional derangement and an ICU mortality rate of > or = 50%. These intervals were then tested on the second half of the data set (the validation set). Maximal scores for each variable were summed to yield a Multiple Organ Dysfunction Score (maximum of 24). This score correlated in a graded fashion with the ICU mortality rate, both when applied on the first day of ICU admission as a prognostic indicator and when calculated over the ICU stay as an outcome measure. For the latter, ICU mortality was approximately 25% at 9 to 12 points, 50% at 13 to 16 points, 75% at 17 to 20 points, and 100% at levels of > 20 points. The score showed excellent discrimination, as reflected in areas under the receiver operating characteristic curve of 0.936 in the development set and 0.928 in the validation set. The incremental increase in scores over the course of the ICU stay (calculated as the difference between maximal scores and those scores obtained on the first day [i.e., the delta Multiple Organ Dysfunction Score]) also demonstrated a strong correlation with the ICU mortality rate. In a logistic regression model, this incremental increase in scores accounted for more of the explanatory power than admission severity indices. CONCLUSIONS: This multiple organ dysfunction score, constructed using simple physiologic measures of dysfunction in six organ systems, mirrors organ dysfunction as the intensivist sees it and correlates strongly with the ultimate risk of ICU mortality and hospital mortality. The variable, delta Multiple Organ Dysfunction Score, reflects organ dysfunction developing during the ICU stay, which therefore is potentially amenable to therapeutic manipulation. (ABSTRACT TRUNCATED)

Humans↗
PubMed1985

An improved automated method for the measurement of thermal thresholds. 1. Normal subjects.

Clinical tests of thermal sensation are poorly quantified and not strictly modality specific. Previous automated thermal testing systems have had limited usefulness with high intra-and inter-individual variability. This paper describes an automated thermal system (Glasgow system) which is an extensive modification of previous techniques to answer these criticisms. It comprises a microprocessor-driven Peltier element and utilises the forced choice method of psychophysical analysis to determine the thresholds to thermal stimulation. In a control group of 106 healthy subjects the mean heat threshold for the wrist was found to be 0.23 degree C (SD = 0.06 degree C) and the mean cold threshold 0.15 degree C (SD = 0.05 degree C). Repeated determinations showed a maximum of 5% intra-individual variation in comparison to previously reported values of up to 150%.

Adolescent↗
PubMedDate not supplied

Soft tissue mineralization: roentgen analysis.

Numerous, incompletely understood, and undetermined physiologic factors may exert further but unappreciated influences on the development of ectopic calcification and ossification. In the former instance, in addition to serum calcium and phosphorous ion concentrations, tissue pH, blood supply, hormones, i.e., vitamin D, vitamin A, and various enzymes (e.g., alkaline phosphatase and pyrophosphatase) may all play significant, ancillary, time-dependent, but as yet undetermined roles. Ossification, like calcification, may occur in association with many types of disorders and under a variety of circumstances, some of which, such as trauma, have been reduplicated in the laboratory. However, experimental conditions that produce ectopic bone, as well as the species that are predilected do not always coincide with clinical observations in man. Not only are there differences between species in regard to susceptibility to ectopic bone production under particular circumstances, i.e., rabbits are the most susceptible and mice the least to mechanical injury, but there are differences between individuals. Individual variability in susceptibility to soft tissue ossification suggests either a personal or familial predilection. If such liability is inherited, this would be an example of an ecogenetic condition, in which someone is susceptible to an environmental agent by virtue of genetic constitution. Histocompatibility (HLS) antigens have provided substantiation of this concept. In the case of soft tissue ossification, causative environmental agents could include trauma, burns, hip replacement, and immobility secondary to neurological insults. In the case of soft tissue calcification, trauma, infections, or repeated injections could constitute the triggering environmental event. Not only do individuals at risk develop bone, but those that do tend to do so in characteristic places. Therefore, there is an additional differential susceptibility at various sites in the same individual. In cases with neurological conditions, thigh muscles are more susceptible than paraspinal muscles. The underlying condition is a further moderator, i.e., in paraplegics, thigh muscles are most apt to be involved. Elbows are most commonly affected after burns regardless of the site of the burn. Ectopic ossification also has a further predilection for distribution. Not only are muscle groups unequal in risk in terms of site, but the type of muscle affected is relevant, since skeletal muscles are involved in these same conditions to the exclusion of smooth muscles.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed2003

A three-center, randomized, controlled trial of individualized developmental care for very low birth weight preterm infants: medical, neurodevelopmental, parenting, and caregiving effects.

Medical, neurodevelopmental, and parenting effects of individualized developmental care were investigated in a three-center, randomized, controlled trial. A total of 92 preterm infants, weighing less than 1250 g and aged less than 28 weeks, participated. Outcome measures included medical, neurodevelopmental and family function. Quality of care was also assessed. Multivariate analysis of variance investigated group, site, and interaction effects; correlation analysis identified individual variable contributions to significant effects. The results consistently favored the experimental groups. The following contributed to the group effects: shorter duration of parenteral feeding, transition to full oral feeding, intensive care, and hospitalization; lower incidence of necrotizing enterocolitis; reduced discharge ages and hospital charges; improved weight, length, and head circumferences; enhanced autonomic, motor, state, attention, and self-regulatory functioning; reduced need for facilitation; and lowered family stress and enhanced appreciation of the infant. Quality of care was measurably improved. Very low birth weight infants and their parents, across diverse settings, may benefit from individualized developmental care.

Caregivers↗
PubMed1999

N-acetyltransferase (NAT2) genotype and susceptibility of sporadic Alzheimer's disease.

The importance of environmental aggression and individual susceptibility to develop Alzheimer's Disease (AD) has been suggested by epidemiological studies on both typical familial and sporadic AD cases. In order to elucidate functions that can influence the susceptibility to AD pathogenesis, we genotyped a group of 53 sporadic late-onset AD patients, matched control individuals and a larger randomly selected non-demented population for the N-acetyltransferase (NAT2). We determined the relative frequencies of individual allele combinations that define a broad range of acetylator phenotypes. Inter-individual variability in the cytotoxic and genotoxic responses to a wide diversity of environmental chemicals is known to result from the polymorphism of NAT2 as well as other drug-metabolizing-enzyme genes. The results presented are the first to demonstrate a significant difference in the NAT2 genotype profiles of sporadic AD patients compared with the healthy population. A lower frequency of the recessive alleles NAT2*6 (chi-squared 1 d.f. = 12.56, P < 0.0004) and NAT2*5B (chi-squared 1 d.f. = 6.72, P < 0.01) was found among the AD population compared with control individuals, which was concomitant with a significantly higher number of NAT2*4 fully active allele homozygotes and heterozygotes (chi-squared 1 d.f. = 5.69, P = 0.017). The most notable observation was the absence of NAT2*5B/NAT2*6 heterozygotes among cases while being present in 22.5% of control individuals (chi-squared 1 d.f. = 13.08, P = 0.0003). These observations indicate that NAT2 is a potential low-penetrance gene in AD pathogenesis, determining an individual susceptibility trait predisposing to this degenerative disease.

Alzheimer Disease↗
PubMed1991

The role of 3 hour distal oesophageal pH monitoring in gastro-oesophageal reflux.

It has been suggested in the literature that an eight hour period of distal oesophageal monitoring is adequate for the diagnosis of reflux in symptomatic patients. The aim of this study was to investigate whether 3 hour intra-oesophageal pH-metry could be substituted for the eight hour test period without loss of sensitivity in the diagnosis of GOR. Twenty patients were tested, 10 of whom had classical De Meester symptoms of GOR and 10 asymptomatic patients served as controls. All were commenced on 3 hour ambulant pH monitoring of the distal oesophagus. This was followed by a separate period of 8 hour testing. Each test had a 50% supine time period. The following variables were determined: (i) number of reflux episodes (ii) number longer than 5 minutes (iii) longest episode of reflux, (iv) percent of time that pH was below 4. Results are analysed using the 'Esophogram' computer program. 8 hour monitoring resulted in a positive diagnosis of GOR in 10 of 10 patients, giving an overall sensitivity of 100%. 3 hour testing was positive in 8 patients (sensitivity of 80%). The best correlations were obtained when comparing total reflux episodes, and the percent of total time pH less than 4, but overall the tests correlate poorly for individual variables. None of the controls had positive 3 or 8 hour testing. We conclude therefore, that 3 hour pH metry may be a useful screening test to confirm symptomatic reflux, and can be performed within a single clinic visit. If negative, arrangements must be made for more prolonged monitoring.

Female↗
PubMed2006

Simulating deformations of MR brain images for validation of atlas-based segmentation and registration algorithms.

Simulated deformations and images can act as the gold standard for evaluating various template-based image segmentation and registration algorithms. Traditional deformable simulation methods, such as the use of analytic deformation fields or the displacement of landmarks followed by some form of interpolation, are often unable to construct rich (complex) and/or realistic deformations of anatomical organs. This paper presents new methods aiming to automatically simulate realistic inter- and intra-individual deformations. The paper first describes a statistical approach to capturing inter-individual variability of high-deformation fields from a number of examples (training samples). In this approach, Wavelet-Packet Transform (WPT) of the training deformations and their Jacobians, in conjunction with a Markov random field (MRF) spatial regularization, are used to capture both coarse and fine characteristics of the training deformations in a statistical fashion. Simulated deformations can then be constructed by randomly sampling the resultant statistical distribution in an unconstrained or a landmark-constrained fashion. The paper also describes a model for generating tissue atrophy or growth in order to simulate intra-individual brain deformations. Several sets of simulated deformation fields and respective images are generated, which can be used in the future for systematic and extensive validation studies of automated atlas-based segmentation and deformable registration methods. The code and simulated data are available through our Web site.

Algorithms↗
PubMed2005

Food choices at lunch during the third year of life: increase in energy intake but decrease in variety.

AIM: Modelling the evolution between the ages of 2 and 3 y of the energy intake and the variety of free food choices at lunch time in relation to children's and context variables. METHODS: One-year follow-up from 2 to 3 y old. In a nursery canteen, food choices at lunch were recorded by trained assistants who monitored portion size. Energy intake and food variety were estimated. Three hundred and ninety-five children were studied, for 112 meals and over 10 mo on average. Mixed models of analysis of variance were used to take into account the longitudinal character of the data. RESULTS: From 2 to 3 y, energy intake increased. Variety decreased during the first 7 mo and then remained constant. The individual variability in mean values and in evolution was high for both variables. Energy was positively linked to BMI at 2 y. Variety was slightly higher for girls and increased with duration of breastfeeding. Energy was higher in September to November than in December-January. Variety was maximal in December-January and in June-July. CONCLUSION: During the third year of life, while energy intake increases, the restriction of food variety appears to be a normal transition phase. Long duration of breastfeeding is associated with higher food variety.

Age Factors↗
PubMed2000

Lung cancer risk in nonsmokers and GSTM1 and GSTT1 genetic polymorphism.

Glutathione S-transferase (GST) polymorphism may contribute to the individual variability in detoxifying lung carcinogens. This effect might be particularly relevant at low-level exposure to environmental carcinogens, such as in nonsmokers exposed to environmental tobacco smoke (ETS). We conducted a case-control study among 122 nonsmoking lung cancer cases and 121 nonsmoking controls from eight countries. Information on environmental exposures was obtained through a personal interview. The presence of GSTM1 and GSTT1 genes was determined using multiplex PCR. GSTM1-positive samples were then analyzed for *1A and *1B polymorphism using an allele-specific amplification-PCR method. GSTM1*2 (null) individuals had an odds ratio (OR) of lung cancer of 1.5 [95% confidence interval (CI), 0.9-2.7]; the risk associated with this genotype was higher for cases with squamous and small cell carcinomas (OR, 2.3; 95% CI, 0.9-6.1) than for cases with adenocarcinomas. It was also elevated in individuals with long-term exposure to indoor wood combustion (OR, 3.1; 95% CI, 0.9-9.9), in subjects who mainly lived in a rural setting (OR, 3.6; 95% CI, 1.0-13), and in cases exposed to occupational carcinogens (OR, 10.7; 96% CI, 0.4-260) but not in subjects exposed to ETS. GSTT1*2 subjects did not show a risk of lung cancer. Our study suggests that the effect of GSTM1 polymorphism in nonsmokers is similar to that found in smokers. It does not seem to interact with ETS exposure, although we cannot exclude that it does in association with exposure to other specific environmental carcinogens.

Adenocarcinoma↗
PubMed1995

Variable activation of lovastatin by hydrolytic enzymes in human plasma and liver. 4.

Lovastatin, widely used to lower cholesterol, is a pro-drug that requires metabolic activation through hydrolysis by carboxyesterases. There appear to be at least three distinct esterases in humans capable of catalysing this reaction, one in plasma and two in the liver. The rate of lovastatin hydroxy acid formation was measured as 15.8 pmol.ml-1.min-1 in plasma, 2.13 pmol.mg-1 protein.min-1 in hepatic microsomes and 0.92 pmol.mg-1 protein.min-1 in cytosol. The data suggest that on average the three esterases together are capable of activating about 220 nmol (90 micrograms) lovastatin per minute per person, to which the esterases of plasma, liver microsomes and liver cytosol contribute approximately 18, 15 and 67%, respectively. All three esterases showed evidence of inter-individual variability. In one of 17 livers, both cytosolic and microsomal esterase activity was completely missing, while two other liver specimens lacked one esterase. Such variability must be expected to influence the therapeutic efficacy of the drug, and they might be related to its occasional toxicity.

Biotransformation↗
PubMed1999

Mood and cognitive disorders in cancer patients receiving cytokine therapy.

Chronic treatment with cytokines is associated with the development of mood and cognitive changes that suggests frontal-subcortical cerebral dysfunction. There is large individual variability in the type and severity of specific symptoms that are reported. The CNS effects of cytokines can be disassociated from the effects of chronic disease, other treatments and medications, and psychological responses to illness. The length of treatment and dose are both important factors in the development of mood disturbance. The finding that treatment chronicity is important makes long-term follow-up of patients on cytokine therapy all the more vital. Most adverse effects of cytokines improve with appropriate treatment of symptoms, although dose reduction or cessation of therapy may be necessary in individual cases. Future studies will be needed to better identify at-risk individuals, to compare the efficacy of various interventions, including antidepressants, stimulants, and opiate antagonists, and to assess the feasibility of treating at-risk individuals prophylactically.

Brain↗
PubMed2006

Genetic variation in thyroid hormone pathway genes; polymorphisms in the TSH receptor and the iodothyronine deiodinases.

Serum thyroid parameters show substantial inter-individual variability, in which genetic variation is a major factor. Findings in patients with subclinical hyper- and hypothyroidism illustrate that even minor alterations in serum thyroid function tests can have important consequences for a variety of thyroid hormone-related clinical endpoints, such as atherosclerosis, bone mineral density, obesity, and heart rate. In the last few years, several studies described polymorphisms in thyroid hormone pathway genes that alter serum thyroid function tests. In this review, we discuss the genetic variation in the TSH receptor and iodothyronine deiodinases. We discuss the possible consequences of these studies for the individual patient and also the new insights in thyroid hormone action that can be obtained from these data.

Animals↗