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Psychological distress and incident cardiovascular disease independent of life's essential 8: a prospective cohort study.

BACKGROUND: Although psychological stress has emerged as an important determinant of cardiovascular disease (CVD) risk, it remains excluded from the recently updated cardiovascular health (CVH) metrics, known as Life's Essential 8 (LE8). This study aimed to examine the association between psychological distress and the incidence of CVD, independent of Life's Essential 8 metrics, in a large Korean adult population. METHODS: This study included 6,410 participants from the Korean Genome and Epidemiology Study Ansan-Ansung cohort, who had no history of CVD and had complete baseline data on psychological distress and Life's Essential 8 cardiovascular health (LE8 CVH) metrics. Psychological distress was assessed using the Psychosocial Wellbeing Index Short Form (PWI-SF). CVD events were identified based on participants' self-reports of physician-diagnosed conditions: myocardial infarction, stroke, coronary artery disease, and congestive heart failure. Cox proportional hazards models were used to examine the association between PWI-SF scores and incident CVD, adjusting for age, sex, residential area, educational attainment, household income, and LE8 CVH metrics. RESULTS: During a median follow-up of 13.8 years, 500 new cases of CVD were identified. Higher PWI-SF scores were independently associated with an increased risk of CVD after adjusting for LE8 CVH metrics and other potential confounders (hazard ratio: 1.321; 95% confidence interval: 1.067-1.636; p = 0.011). CONCLUSION: These findings suggest that higher levels of psychological distress are independently associated with an increased risk of CVD, even after accounting for established LE8 CVH metrics. Incorporating psychological distress into future CVH assessments may enhance risk stratification and prevention strategies.

Humans

The association of cardiovascular health with new-onset pulmonary hypertension and the mediating role of proteomic signatures.

BACKGROUND: The cardiovascular health (CVH) metrics have been reported to play an important role in the development of noncommunicable chronic diseases, yet its link to pulmonary hypertension (PH) risk and the underlying biological mechanisms remain unclear. This study aimed to investigate the association of CVH with PH risk and elucidate the mediating role of plasma proteomic signatures. METHODS: A total of 279 220 participants without PH at enrollment of the UK Biobank were included. Cox regression was used to quantify the association between CVH and incident PH. Proteome-wide association analysis, mediation analysis, and functional enrichment analysis were conducted to identify protein mediators. Key hub proteins were further validated at the transcriptional level through quantitative polymerase chain reaction (qPCR) in an animal model of PH, as well as at the protein level, and by macrophage-specific knockdown of interleukin (IL)-6 and CCL4 to evaluate its impact on rat pulmonary artery smooth muscle cell (PASMC) migration and proliferation. RESULTS: Over a median 13.2-year follow-up, 1325 PH cases occurred. Compared to the lowest CVH, participants with moderate and high CVH had 59% [hazard ratio (HR): 0.41; 95% confidence interval (CI): 0.33-0.49] and 82% (HR: 0.18; 95% CI: 0.14-0.23) lower risk, respectively. Proteomic analyses revealed that this association was significantly mediated by a distinct plasma protein signature. Pathway enrichment analysis indicates that proteins are significantly enriched in inflammatory/immune pathways, and key hub proteins were identified as participating in the central mechanism pathway. In the lung tissue of PH rat models, the mRNA and protein expression levels of IL-6 and C-C motif chemokine ligand 4 (CCL4) were significantly elevated. Furthermore, functional assays demonstrated that knockdown of IL-6 or CCL4 in macrophages significantly attenuated the migration and proliferation of rat PASMCs in vitro. CONCLUSION: High CVH level, defined by Life's Essential 8 (LE8), is significantly linked to a reduced risk of developing PH. This protective effect is primarily mediated by a proteomic signature, revealing the role of signaling pathways such as cytokine-cytokine receptor interaction in the prevention of PH.

Hypertension, Pulmonary

Genetic and Lifestyle Factors Influence High 1-Hour Plasma Glucose, a Predictor of Type 2 Diabetes Mellitus.

BACKGRUOUND: High 1-hour plasma glucose (1-h PG) level has been proposed by the International Diabetes Federation to identify high-risk individuals and diagnose type 2 diabetes mellitus (T2DM). In a longitudinal cohort, we examined T2DM risk, &#x3b2;-cell function, and the effects of genetic and lifestyle factors on high 1-h PG. METHODS: We analyzed 7,464 participants without T2D at baseline from a community-based prospective cohort in Korea, who underwent biennial 2-h 75-g oral glucose tolerance tests over 14 years. Incident T2D risk were assessed across 1-h PG groups: < 155, 155-208, and &#x2265; 209 mg/dL. In 6,588 participants with at least two 1-h PG measurements, we analyzed 1-h PG trajectories by T2D polygenic risk score (PRS; low, 1st quintile; intermediate, 2nd-4th quintiles; high, 5th quintile) and lifestyle, assessed using Life's Essential 8. RESULTS: Compared to the <155 mg/dL group, hazard ratios for T2DM were 3.34 (95% confidence interval [CI], 2.99 to 3.74; P<0.001) for 155-208 mg/dL, and 6.81 (95% CI, 5.81 to 7.98; P<0.001) for &#x2265;209 mg/dL. Both groups had lower baseline disposition index compared to the <155 mg/dL group (57.3% and 72.7%, respectively; both P<0.001). Higher T2DM PRS was associated with elevated baseline 1-h PG (low: 131 mg/dL, intermediate: 141 mg/dL, high: 151 mg/dL) and faster increase in 1-h PG (1.36 vs. 1.85 vs. 2.21 mg/dL/year; all P<0.001). Importantly, healthy lifestyle attenuated the rate of increase across all PRS groups. CONCLUSION: High 1-h PG predicts T2DM risk and is associated with &#x3b2;-cell dysfunction. The 1-h PG level is influenced by genetic risk and can be modified with a healthy lifestyle.

Humans

DNA methylation signatures in skeletal muscle associated with physical function in healthy older adults.

Despite the substantial variability in physical function among older adults, the molecular mechanisms remain poorly characterized, particularly within skeletal muscle. This study aimed to determine the patterns of DNA methylation in skeletal muscle associated with physical function in healthy older adults. We analyzed DNA methylation (EPIC v2 array; 875,554 CpG sites) in skeletal muscle from 92 healthy older adults (median age 74; 62% female). Associations were examined across five phenotypes: Short Physical Performance Battery (SPPB), 6-min walk test (6MWT), handgrip strength, perceived disability (PAT-D), and lifestyle health (modified Life's Essential 8). Linear regression models adjusted for age, sex, race, BMI, and muscle fiber composition. Genomic inflation corrected via the BACON method (FDR&#x2009;<&#x2009;0.05). Gene set enrichment analysis was performed on suggestive hits (FDR&#x2009;<&#x2009;0.1). We identified significant differentially methylated probes (DMPs) and regions (DMRs) across all phenotypes: SPPB (70 DMPs, 22 DMRs), 6MWT (16 DMPs, 566 DMRs), handgrip strength (2 DMRs), PAT-D (19 DMPs, 1 DMR), and lifestyle health (2 DMPs). DMRs largely overlapped promoters. Identified genes overlapped known musculoskeletal and neurological GWAS hits, including RUNX2 and FOXL1 (bone mineral density), IGFBP3 (muscle mass), and NEK1 and SHANK1 (neurological function). Enrichment analysis revealed that 6MWT-associated genes relate to nervous and skeletal system development, while handgrip-associated genes involve cytoskeletal dynamics and protein assembly. Epigenetic variation in aging skeletal muscle is associated with physical function. The enrichment of pathways related to nervous and musculoskeletal development suggests specific epigenetic mechanisms underlying functional decline, offering potential targets for intervention in older adults.

DNA methylation

Polygenic Risk Based Detection and Treatment of Subclinical Coronary Atherosclerosis in the PROACT Clinical Trials.

BACKGROUND: Coronary artery disease (CAD) polygenic risk scores (PRS) may identify individuals at elevated genetic risk "flying under the radar" in contemporary practice. The aims of the PROACT (Polygenic Risk Based Detection and Treatment of Subclinical Coronary Atherosclerosis) trials are to prospectively identify these individuals, quantify subclinical coronary plaque, and slow its progression with pharmacologic interventions. OBJECTIVES: The aim of this study is to report interim feasibility and implementation findings from PROACT, a genotype-first, biobank-enabled trial, characterizing eligibility yield, callback engagement, and subclinical coronary atherosclerosis on coronary computed tomographic angiography among individuals with high CAD PRS. METHODS: Within a hospital-based biobank, adults 40 to 75 years of age with high CAD PRS, without cardiovascular disease, and not on lipid-lowering therapy were invited. The authors characterize 2,495 eligible individuals with high CAD PRS, report on the feasibility and early operational outcomes of a genotype-first callback strategy for a clinical trial in the first 1,314 invited, and describe plaque prevalence by age and sex in the first 204 participants using coronary computed tomographic angiography. RESULTS: Among 64,092 genotyped participants, 2,495 (3.9%) were eligible and had high CAD PRS despite low clinical risk (median 10-year pooled cohort equations risk for atherosclerotic cardiovascular disease 3%; Q1-Q3: 1%-8%). Recruitment showed high engagement: among 1,314 invited individuals, 283 (21.5%) opted in, and 204 (15.5%) completed baseline imaging. Compared with participants who did not opt in, those who opted in had higher specialty care engagement and lived closer to the study site. Analysis of the first 204 participants enrolled by January 31, 2025 (mean age 56.3 &#xb1; 8.5 years, 69% women), showed that despite the low clinical risk and favorable cardiovascular health (mean Life's Essential 8 score 73.3 &#xb1; 11.5 vs the U.S. average of &#x223c;65), one-half the participants (102 of 204) had subclinical plaque. Subclinical plaque prevalence was 76.2% in men and 38.3% in women and was high across age groups. CONCLUSIONS: These exploratory findings highlight the feasibility of implementing genotype-first recruitment for prevention trials and reveal a large proportion of "silent" high-genetic risk individuals with subclinical plaque for whom pharmacotherapy could be beneficial but who remain undetected by standard clinical assessments. (Polygenic Risk Based Detection of Subclinical Coronary Atherosclerosis and Change in Cardiovascular Health [PROACT 1], NCT05819814; Polygenic Risk Based Detection of Subclinical Coronary Atherosclerosis and Intervention With Statin and Colchicine [PROACT 2], NCT05850091).

Adult

Hypoplasia renum: a comparative study of diagnosis, clinical course and management.

Twenty patients with hypoplastic kidney (12 men and 8 women, left kidney in 13 cases, right kidney in 7 cases) were observed between 1961 and 1971. The age of the patients ranged from 14 to 60 years. The anomaly predominated (65% of the patients) in the third and fourth decades of life; in this age the diagnosis of the true nature of the condition was often due to complications requiring examination. Carefully taken history and complete radiological survey are essential for the recognition. The value and characteristic features yielded by particular investigation are discussed. In 8 patients clincial diganosis was confirmed at operation. Most common complications of hypoplastic kidney included hypertension, lithiasis, hydronephrosis, pyelonephritis and periodic hematuria. In 9 pateints (4 women and 5 men) renal hypoplasia was associated with other anomalies of the genitourinary tract.

Adolescent

Disposition of guanethidine during chronic oral therapy.

The plasma level and urinary excretion rate of guanethidine have been measured in 30 patients during oral maintenance therapy, and in 5 patients following discontinuous of therapy. A significant correlation was found between the daily average urinary excretion and the maintenance dose, although wide interindividual variation was noted among patients maintained on the same dose. A statistically significant correlation was also observed between the area under the plasma level curve during the dose interval and the oral maintenance dose. After discontinuation of chronic therapy, the half-life of 1.5 days of the initial phase of elimination was essentially in agreement with the half-life of almost 2 days determined in acute studies. In addition, a second phase of elimination with a half-life of 4 to 8 days was observed.

Administration, Oral

Pharmacokinetics of cefaclor in normal subjects and patients with chronic renal failure.

We studied the pharmacokinetics of cefaclor, a new cephalosporin antibiotic, in normal subjects and subjects with chronic renal failure. Cefaclor was largely, but not entirely, eliminated by the kidneys. The cefaclor half-life in normal subjects was 40 to 60 min; in subjects with essentially no renal function, it increased to 3 h. In normal subjects, 50 to 70% of a 250-mg dose was excreted in the urine within 8 h. The linear relationship between the elimination constant and creatinine clearance allowed the construction of a useful dosage modification nomogram.

Animals

Interactions of trace metals in mouse and rat tissues; zinc, chromium, copper, and manganese with 13 other elements.

Tissues of rats and mice fed a nonessential metal in drinking water for life were analyzed for the essential metals chromium, copper, manganese and zinc. The study involved 505 rats and 843 mice. Livers, lungs, hearts, kidneys and spleens were pooled in groups according to age at death, averaging 5 for rats and 8 for mice, in order to provide adequate sample weight. Copper was significantly higher in livers of rats fed tin, germanium, niobium and zirconium than in controls. Similarly, niobium was associated with deposition of manganese in heart and zinc deposition in liver. Chromium levels were depressed in heart, kidney and spleen by germanium. In mice the greatest effects occurred when indium and rhodium were fed, all four essential trace metals exhibiting raised levels principally in kidney but also in heart and spleen. Chromium levels were raised in all organs but heart when hexavalent chromium was fed. From these data it is apparent that the ingestion of a nonessential metal can enhance the retention of an essential trace metal, perhaps thus avoiding toxicity from the nonessential one.

Animals

[Age dependence of adenylate cyclase activity and cAMP generation in aortas and femoral arteries of rats (author's transl)].

UNLABELLED: It is well-known that the cAMP-adenylate cyclase system is important in mediating the effects of numerous hormones. We investigated the age-dependent behaviour of this system in aortas and femoral arteries of male Wistar rats (at the age of 10 days, 1, 4, 8, 12, and 22 months). RESULTS: 1. The basic adenylate cyclase activity had considerably been decreased beyond the first month of life, thereafter it was almost constant. 2. The response of adenylate cyclase to guanylyl-imidodiphosphate and NaF had essentially been elevated since the 4th month of age. 3. The possibility of stimulating the cAMP generation due to epinephrine and histamine had substantially been increased since the 12th month of age.

Adenylyl Cyclases

[Adenyl cyclase activity and the stimulation of adenosine 3',5'-cyclic monophosphate in blood vessel walls during ageing and under stress (author's transl)].

It is well-known that the cAMP-adenylate cyclase system is important in mediating the effects of numerous hormones. We investigated the age-dependent behaviour of this system in aortas and femoral arteries of male Wistar rats (at the age of 10 days, 1, 4, 8, 12, and 22 months). It was found that: The basic adenylate cyclase activity had considerably been decreased beyond the first month of life, thereafter it was almost constant. The response of adenylate cyclase to guanylyl-imidodi-phosphate and NaF had essentially been elevated since the 4th month of age. The possibility of stimulating the cAMP generation due to epinephrine and histamine had substantially been increased since the 12th month of age. Besides the ability of adrenaline and histamine to stimulate the formation of cyclic AMP was investigated in broken cell preparation and intact cells of smooth muscle of the aorta and femoral artery of rats which had been subjected to daily intermittend immobilization of 1, 3, and 17 weeks. It was found that this type of stress led to an instability of the blood pressure which was associated with an increase in the sensitivity of adenylate cyclase in the broken cell preparations from the arteries to adrenaline and histamine and with a heightened cyclic AMP response to the two hormones in the intact arterial smooth muscle cells. The sensitivity of cardiac adenylate cyclase for adrenaline remained unchanged.

Adenylyl Cyclases

On the decrease in the life expentancy of black males in Michigan.

The 1970 census reported that there were slightly more than 1 million nonwhites among Michigan's 8,875,000 residents. Ninety-five percent of these nonwhites are black, and 75 percent live within the city limits of Detroit, compared with 10 percent of the State's white residents. Between 1959-61 and 1969-71, life expectancy at birth increased about 1 year for black and white females, essentially remained unchanged for white males, and decreased more than 3 years for black males. In 1969-71, life expectancy was 61 years for black males, 68 years for white males, 69 years for black females, and 75 years for white females. Much of this growing disparity noted resulted from a dramatic rise in deaths of black males in the 15-44 year age group. Two-thirds of this increase was caused by a major rise in mortality from two causes--accidents and homicides. While death rates for black males decreased for a number of other leading causes, these generally remained higher than similar figures for each of the other three race-sex groups. Given current rates, one of eight black males in Michigan ultimately will die from an accident or from homicide. This probability is 1 of 17 for white males, 1 of 30 for white females, and 1 of 26 for nonwhite females. Homicides reduced the life expectancy of black males by 2.3 years, compared with 0.2 year for white males, less than 0.005 year for white females, and 0.5 year for black females. More than three-quarters of all homicides of black males in Michigan in 1973 were caused by handguns.

Accidents

Tissue differentiation and susceptibility to embryonal tumor induction by ethylnitrosourea in the opossum.

Opossums (Didelphis virginiana Kerr) exposed to 100 mg ENU/kg in single or incremental doses early in postnatal life developed a spectrum of epithelial and mesenchymal neoplasms including several types of embryonal neoplasms not previously induced in laboratory animals. A correlation was apparent to a varying degree between susceptibility to tumor induction and the state of morphologic maturation of the presumed target tissues at the light microscopic level for embryonal tumors of the eye, kidney, and brain. The susceptibility of the opossum eye to an ENU-induced intraocular teratoid medulloepithelioma extended over the period from 1 to between 3 and 4 weeks of age and was correlated with the differentiation of the apparent target cell, the nonpigmented ciliary epithelium of the pars ciliaris retinae. Induction of nephroblastomas was correlated with the presence in the kidney of stem cells (metanephric blastema) through the period from birth to between 6 and 8 weeks of age. Although susceptibility of the opossum brain to ENU induction of gangliogliomas was correlated with the state of differentiation of the germinal matrix from birth to 56 days of age, induction of these tumors was essentially limited to the 1st week postpartum. No definite correlation between vulnerability to tumor induction and tissue maturation was evident for a tumor of the jaw (ameloblastoma) with presumed origin from embryonic dental remnants. Our results indicated that the opossium early in postnatal life is a useful model for the induction and characterization of certain of the major dysontogenetic tumors, which have been difficult or impossible to reproduce in the traditional laboratory species.

Age Factors

Rapid onset of essential fatty acid deficiency in the newborn.

To study the effect of fat-free alimentation on essential fatty acids (EFA), their levels in plasma phospholipids, cholesterol esters, triglycerides, and free fatty acids were measured in five sick newborns. Four patients were under 32 weeks of gestation; three were small for gestational age and one was an infant of a diabetic mother. All developed biochemical evidence of EFA deficiency during the first week of life--the smallest infant did so by the second day. Biochemical evidence of EFA deficiency included a decrease in plasma lipid arachidonic and linoleic acids, an increase in 5,8,11-eicosatrienoic acid, palmitoleic, and oleic acids and a trienoic/tetraenoic ratio of more than 0.4. Oral feeding with EFA reversed these changes. The two infants showing the most severe biochemical evidence of EFA deficiency died. Neither exchange transfusion nor multiple blood transfusions prevented or corrected the development of EFA deficiency. An alternative method for efficient and safe delivery of EFA to such infants is required.

Blood Transfusion

[Long-term results in electric pacemaker therapy].

It is reported on experiences and results in 317 patients with altogether 690 implantations of pacemakers from 1963 to 1974 and under comparison and with reference to the up to now existing long-term results published in literature state and tendency of the medical and technical development of the electric heart stimulation are discussed. The average age of outpatients was 62.9 years with a peak of age of 46% in the 7th decade of life. 60% were male patients, 40% female ones. With about 50% the constant total atrioventricular block was the most frequent indication. 63% of the familiar types of pacemakers were biotronic apparatuses, 36% of them with fixed frequency. The average duration of the function of all apparatuses was calculated with 20.1 months. Hereby the biotronic types had the longest average function times of 26.7 months (frequency fixed) or 26.3 months (regulated). In 373 reimplantations is shown that 2.17 apparatuses were implanted in each patient. The total number of complications was 21.2% related to the total number of implantations. With 8.9% breaks of the cable were in the first place in myocardial electrodes. Dislocations of transvenous electrodes were observed only in 4.5% of our cases. With 5.8% pressure necroses and infections were the cause of complications stood in the second place concerning frequency. The total lethality was 23.7% with an age peak of 38% in the 8th decade of life. 13.4% of the cases of death belong to an early lethality with a prevailing part of epicardial implantations. In our patients the cumulative survival rate was after 1 year 89.3%, after 5 years 62.3% and after 8 years 47.7%. The 50% survival rate was ca. 7.3 years. In comparison to the population of the same age the average expectance of life is transgressed by about 6 years. The prolongation of the survival time by electrostimulation compared with the conservative treatment of the total atrioventricular block with Adams-Stokes-syndrome is the essential result of the pacemaker therapy.

Adams-Stokes Syndrome

Transdermal fentanyl: clinical pharmacology.

The transdermal therapeutic system (TTS) fentanyl has been designed for rate-controlled drug delivery. It provides a convenient regimen for the use of a drug previously limited by a short duration of action and a noninvasive parenteral route for a drug that is unsuitable for oral administration. TTS fentanyl has been developed to provide continuous controlled systemic delivery of fentanyl base for 72 hr. It is a rectangular, transparent unit composed of a protective peel strip and four functional layers. The amount of fentanyl released from each system (25 micrograms/hr per 10 cm2) is proportional to the surface area. So far, four patch sizes are available (10-40 cm2). When the system is applied, a fentanyl depot concentrates in the upper skin layers. Fentanyl plasma concentrations are not measurable until 2 hr after application, and it takes 8-16 hr latency until full clinical fentanyl effects are observed. Steady-state serum concentrations are obtained after several sequential 72-hr applications, and these are maintained for as long as a system is applied. Following removal, serum fentanyl concentrations decline gradually and fall about 50% in approximately 16 hr. This prolonged apparent elimination half-life occurs because fentanyl continues to be absorbed from the skin. Transdermal fentanyl transport is essentially the same between the chest, abdomen, and thigh. The skin-permeability constant is about 0.0125 mL/hr/cm2, much lower than the regional blood supply to a chest-skin area. Because of potential permeability variations among individuals, a special rate-controlling membrane in the system provides additional control of drug release.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Cutaneous

Oxidation-reduction potentials of human fetal hemoglobin and gamma chains. Effects of blocking sulfhydryl groups.

The oxidation-reduction equilibrium of the gamma chains of human fetal hemoglobin (Hb F) has been studied and compared with that of the alpha and beta chains of human adult hemoglobin (Hb A). The effects of the sulfhydryl (--SH) reagents, iodoacetate, iodoacetamide, and p-mercuribenzoate (PMB), on the three kinds of chains and on Hb F have been compared. The midpoint potentials (E-m) of all three sorts of chains are lower than those of tetrameric hemoglobin A or F. The E-m values of alpha chains are the lowest, E-m = 0.049 volt at 6 degrees, and are unaffected by pH change or by PMB treatment, at least from pH 6 to 8. The E-m values of beta-SH chains are higher; E-m = 0.102 volt at pH 7, decreasing to 0.050 volt at pH 8, both at 6 degrees. These results agree with those of Banerjee and Cassoly ((1969) J. Mol. Biol. 42, 337-349). They reported no effect of PMB on beta chains, but we find that 2 eq of PMB/chain raise E--M to 0.139 volt at pH 7 at 6 degrees, chiefly as the result of reaction at beta-93, not at beta-112. Carboxymethylation at beta-93 has an insignificant effect compared with that of PMB. The oxidation-reduction potential of gamma chains is similar to that of beta chains. E-m = 0.098 volt at pH 7 at 6 degrees, decreasing to 0.064 at pH 8 and 0.010 at pH 9. The effects of --SH reagents, reacting at position gamma-93 (the only --SH group present in gamma chains), are essentially the same as those seen with beta chains. The oxidation-reduction potential of Hb F is almost identical with that of Hb A, except for being 0.008 volt lower at pH 6 at 6 degrees. This agrees with the results reported by Flohe and Uehleke ((1966) Life Sci. 5, 1041-1045). PMB or iodoacetamide treatment lowers E-m by 0.02 to 0.03 volt, depending on the pH, from 6 to 9, in much the same way as previously reported for Hb A(Brunori, M., Taylor, J.F., Antonini, E., Wyman, J., and Rossi-Fanelli, A. (1967) J. Biol. Chem. 242, 2295-2300). The "residual oxidation Bohr effect" noted in Hb F can be attributed to the oxidation Bohr effect of the gamma chains. The apparent pK of the heme-linked water molecule was found at 25 degrees to be, for Hb F, 8.1; for gamma-SH chains, 7.85; for gamma-PMB chains, 8.35; and for gamma chains treated with iodoacetate, 7.80. Sedimentation coefficients, s-20, w, at a protein concentration of 5 mg/ml, were found to be, for fetal hemoglobin 4.09, for iodoacetamide-treated fetal hemoglobin 4.04, for PMB-treated fetal hemoglobin 3.41, for fetal gamma-SH chains 4.25, and for fetal gamma-PMB chains 3.08.

Adult

Thyroid hormone up-regulates NGFI-A gene expression in rat brain during development.

NGFI-A is an immediate-early response gene induced by signals that initiate growth and differentiation. Its mRNA encodes a sequence-specific transcriptional activator possibly implicated in the control of brain developmental processes. Due to the essential role of thyroid hormone for a correct brain development, we have now investigated the possible regulation by 3,5,3'-triiodo-L-thyronine (T3) of NGFI-A gene expression during maturation of the central nervous system. Our results indicate that expression of mRNA encoding NGFI-A transcription factor is about 8-fold decreased in the brain of neonatal hypothyroid rats. No changes were seen when hypothyroidism was induced in adult life. T3 treatment increased NGFI-A mRNA within 1 h, suggesting that thyroid hormone effect is likely to be a direct one. These data indicate a strong regulation by thyroid hormone of the expression of the growth factor inducible gene NGFI-A during brain development, making this gene a suitable model to study T3 action in the early developing nervous system.

Animals