Familial hyper- and hypopigmentation with age-related pattern change

2005 ◽  
Vol 132A (2) ◽  
pp. 215-218 ◽  
Author(s):  
Joe J. Hoo ◽  
Antony E. Shrimpton
Keyword(s):  
Pattern Change ◽  
Age Related ◽  
Familial Hyper ◽  
Related Pattern

Pituitary-adrenal response to bacterial endotoxin in developing rats

1988 ◽  
Vol 255 (4) ◽  
pp. E525-E530 ◽  
Author(s):  
L. Witek-Janusek
Keyword(s):  
Plasma Corticosterone ◽  
Neonatal Rat ◽  
Bacterial Endotoxin ◽  
Plasma Acth ◽  
Adult Rats ◽  
Age Related ◽  
Corticosterone Response ◽  
Adrenal Response ◽  
Old Rats ◽  
Related Pattern

The neonatal rat is very sensitive to the lethal effects of bacterial endotoxin. Because of the adaptive importance of pituitary-adrenal secretions to stress, this study examined the ontogeny of the plasma corticosterone and adrenocorticotropic hormone (ACTH) responses to endotoxin. The lethal sensitivity of young rats to endotoxin ranged from 0.5 to 30 mg/kg (ip) in the 1- to 21-day-old rat. After endotoxin treatment, the 1- and 2-day-old rat showed marked elevations of corticosterone similar in magnitude to that seen in 21-day-old and adult rats; however, significantly depressed corticosterone increments were observed in the 5-, 10-, and 14-day-old rats. This age-related pattern of adrenocortical secretion was correlated with the developing rat's corticosterone response to exogenous ACTH. In contrast, endotoxin administered to 5-, 10-, and 14-day-old rats resulted in increments of plasma ACTH similar to those observed in the 21-day-old and adult rats. Although plasma ACTH levels increased by 84-127% in the 1- and 2-day-old rats, these increases were significantly less than those of rats at all other ages tested. Thus the newborn rat mounts an effective corticosterone response to endotoxin, loses this ability between ages 5-14 days, and regains this response at 21 days of age. Because the hyporesponsive ages exhibit a marked increase in ACTH secretion, the loss of the adrenocortical response to endotoxin appears to be a result of a depressed responsiveness of the adrenal cortex to ACTH.

Motor unit firing rates during constant isometric contraction: establishing and comparing an age-related pattern among muscles

2021 ◽  
Author(s):  
Eric A. Kirk ◽  
Anita D. Christie ◽  
Christopher A. Knight ◽  
Charles L. Rice
Keyword(s):  
Older Adults ◽  
Motor Unit ◽  
Isometric Contraction ◽  
Voluntary Contraction ◽  
Age Related ◽  
Motor Unit Firing ◽  
Euclidean Distances ◽  
Intramuscular Electromyography ◽  
Related Pattern ◽  
Variance Explained

Motor unit (MU) firing rate (FR) frequency is lower in aged adults, compared with young, at relative voluntary contraction intensities. However, from a variety of independent studies of disparate muscles, the age-related degree of difference in FR among muscles is unclear. Using a standardized statistical approach with data derived from primary studies, we quantified differences in FRs across several muscles between younger and older adults. The dataset included 12 different muscles in young (18-35) and older adults (62-93 years) from 18 published and one unpublished study. Experiments recorded single MU activity from intramuscular electromyography during constant isometric contraction at different (step-like) voluntary intensities. For each muscle, FR ranges and FR variance explained by voluntary contraction intensity were determined using bootstrapping. Dissimilarity of FR variance among muscles was calculated by Euclidean distances. There were 3-fold differences in the absolute frequency of FR ranges across muscles in the young (soleus 8-16 and superior trapezius 20-49 Hz), but in the old, FR ranges were more similar and lower for 9 out of 12 muscles. In contrast, the explained FR variance from voluntary contraction intensity in the older group had 1.6-fold greater dissimilarity among muscles than the young (p < 0.001), with FR variance differences being muscle dependent. Therefore, differences between muscle FR ranges were not explained by how FRs scale to changes in voluntary contraction intensity within each muscle. Instead, FRs were muscle dependent but were more dissimilar among muscles in the older group in their responsiveness to voluntary contraction intensity.

scholarly journals O32 Ontogeny of human kidney OCT2 expression across the paediatric age range

2019 ◽  
Vol 104 (6) ◽  
pp. e14.2-e14
Author(s):  
N Smeets ◽  
B van Groen ◽  
J Pertijs ◽  
M Wilmer ◽  
B Smeets ◽  
...  
Keyword(s):  
Organic Cation ◽  
Basolateral Membrane ◽  
Age Groups ◽  
Kidney Tissue ◽  
Human Kidney ◽  
Organic Cation Transporter ◽  
Age Related ◽  
Paediatric Age ◽  
Organic Cation Transporter 2 ◽  
Related Pattern

BackgroundIn adults, the organic cation transporter 2 (protein name OCT2, gene name SLC22A2) is localised in the kidney proximal tubules where it mediates organic cation secretion. Hence, the transporter plays a role in the disposition and excretion of several drugs and drug-drug interactions. To better understand the disposition of OCT2 substrate drugs in children, we studied OCT2 localisation and expression in paediatric kidney tissue.MethodsThe expression of OCT2 was visualised in tissue using immunohistochemical staining. Tissues were derived post-mortem from children aged 0 -14 years. Gestational age varied between 24 and 40 weeks. Intensity of the staining at the basolateral membrane was scored by two individual observers using three categories; negative, detectible and high. Agreement between two observers was determined using Cohen’s kappa.Results44 kidney samples (n=17 neonates, n=17 infants, n=7 children, n=3 adolescent) were analysed and scored. There was substantial agreement between two judgements with a kappa of 0.773 (p< 0.005). No age related pattern was observed in the expression of OCT2. Even in the youngest age group, the expression of OCT2 was clearly visible.ConclusionThe kidney expression of OCT2 did not show an age-related pattern. In all age groups, expression levels were similar and OCT2 was properly localised at the basolateral membrane. These findings suggest that, with increasing age, OCT2 will not influence the renal excretion of its substrates.Disclosure(s)Nothing to disclose

scholarly journals Relationship Between Serum IGF-1 and BMI Differs by Age

2020 ◽  
Author(s):  
Rehab A Sherlala ◽  
Candace M Kammerer ◽  
Allison L Kuipers ◽  
Mary K Wojczynski ◽  
Svetlana V Ukraintseva ◽  
...  
Keyword(s):  
Family Study ◽  
Age Groups ◽  
Serum Levels ◽  
The Third ◽  
Age Related ◽  
Long Life ◽  
Using Data ◽  
The Relationship ◽  
Nutritional Examination Survey ◽  
Related Pattern

Abstract Background Serum levels of insulin-like growth factor 1 (IGF-1) and body mass index (BMI) are both associated with susceptibility to age-related diseases. Reports on the correlation between them have been conflicting, with both positive to negative correlations reported. However, the age ranges of the participants varied widely among these studies. Methods Using data on 4241 participants (aged 24–110) from the Long Life Family Study, we investigated the relationship between IGF-1 and BMI by age groups using regression analysis. Results When stratified by age quartile, the relationship between IGF-1 and BMI varied: in the first quartile (Q1, 20–58 years) the relationship was negative (β = −0.2, p = .002); in Q2 (58–66 years) and Q3 (67–86 years) the relationship was negative (β = −0.07, β = −0.01, respectively) but nonsignificant; and in Q4 (87–110 years) the relationship was positive (β = 0.31, p = .0002). This pattern did not differ by sex. We observed a similar age-related pattern between IGF-1 and BMI among participants in the third National Health and Nutritional Examination Survey. Conclusions Our results that the relationship between IGF-1 and BMI differs by age may explain some of the inconsistency in reports about their relationship and encourage additional studies to understand the mechanisms underlying it.

HPV Prevalence in cytomorphologically normal cervical scrapes of pregnant women as determined by PCR: The age-related pattern

1995 ◽  
Vol 46 (2) ◽  
pp. 97-102 ◽  
Author(s):  
A. M. de Roda Husman ◽  
J. M. M. Walboomers ◽  
E. Hopman ◽  
O. P. Bleker ◽  
Th. M. J. Helmerhorst ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Hpv Prevalence ◽  
Age Related ◽  
Related Pattern

scholarly journals Age-related pattern and monocyte-acquired haemozoin associated production of erythropoietin in children with severe malarial anaemia in Ghana

2014 ◽  
Vol 7 (1) ◽  
Author(s):  
James Abugri ◽  
John Kweku Amissah Tetteh ◽  
Lateef Adebayo Oseni ◽  
Henrietta Esi Mensah-Brown ◽  
Rupert Kantunye Delimini ◽  
...  
Keyword(s):  
Severe Malarial Anaemia ◽  
Associated Production ◽  
Age Related ◽  
Related Pattern

scholarly journals DHEA deficiency syndrome: a new term for old age?

1999 ◽  
Vol 163 (1) ◽  
pp. 1-5 ◽  
Author(s):  
JP Hinson ◽  
PW Raven
Keyword(s):  
Replacement Therapy ◽  
Adrenal Cortex ◽  
Old Age ◽  
Deficiency Syndrome ◽  
Medical Supervision ◽  
Ageing Effects ◽  
Age Related ◽  
The Usa ◽  
Related Pattern

Dehydroepiandrosterone (DHEA) is a steroid secreted by the adrenal cortex, with a characteristic, age-related, pattern of secretion. The decline of DHEA concentrations with age has led to the suggestion that old age represents a DHEA deficiency syndrome and that the effects of ageing can be counteracted by DHEA 'replacement therapy'. DHEA is increasingly being used in the USA, outside medical supervision, for its supposed anti-ageing effects. This commentary weighs the evidence for the existence of a DHEA deficiency syndrome and considers the value of DHEA 'replacement therapy'.

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