The role of fetal adrenal hormones in the switch from fetal to adult globin synthesis in the sheep

1985 ◽  
Vol 104 (1) ◽  
pp. 165-170 ◽  
Author(s):  
E. M. Wintour ◽  
M. B. Smith ◽  
R. J. Bell ◽  
J. G. McDougall ◽  
M. N. Cauchi
Keyword(s):  
In Utero ◽  
Rate Of Change ◽  
Bilateral Adrenalectomy ◽  
Adrenal Hormones ◽  
Globin Synthesis

ABSTRACT The switch from γ (fetal) to β (adult) globin production was studied by the analysis of globin synthesis in chronically cannulated ovine fetuses and newborn lambs. The γ/α globin synthesis ratio decreased from 0·98 ± 0·11 (s.d.) (n = 4 samples) at 100–120 days of gestation to 0·15± 0·07 (n = 4) in lambs of 150–156 days post-conception, and the β/α synthesis ratio increased from 0·04 ± 0·06 (n = 4) to 1·13 ± 0·21 (n = 4) over the same period. In bilaterally adrenalectomized fetuses, which survived in utero until 151–156 days, the γ/α and β/α synthesis ratios were 0·64 ± 0·14 (n = 3) and 0·25 ± 0·07 (n = 3) respectively in the 150- to 156-day period. Bilateral adrenalectomy did not affect the time of onset of β globin synthesis, but significantly decreased the rate. In one bilaterally adrenalectomized fetus the infusion of increasing concentrations of cortisol restored the rate of β globin synthesis to normal. Treatment of three intact fetuses with 100 μg cortisol/h for 3 weeks, from 100 to 121 days, did not affect the timing or rate of switch from γ to β globin synthesis. Thus fetal adrenal secretions, probably cortisol, affected the rate of change of γ to β globin synthesis but other factors must have been involved in the initiation of the switch. J. Endocr. (1985) 104, 165–170

scholarly journals Neuroplacentology in congenital heart disease: placental connections to neurodevelopmental outcomes

2021 ◽  
Author(s):  
Rachel L. Leon ◽  
Imran N. Mir ◽  
Christina L. Herrera ◽  
Kavita Sharma ◽  
Catherine Y. Spong ◽  
...  
Keyword(s):  
Brain Development ◽  
Congenital Heart ◽  
Fetal Brain ◽  
In Utero ◽  
Structure And Function ◽  
Brain Growth ◽  
Neurodevelopmental Outcomes ◽  
Fetal Brain Development ◽  
And Function

Abstract Children with congenital heart disease (CHD) are living longer due to effective medical and surgical management. However, the majority have neurodevelopmental delays or disorders. The role of the placenta in fetal brain development is unclear and is the focus of an emerging field known as neuroplacentology. In this review, we summarize neurodevelopmental outcomes in CHD and their brain imaging correlates both in utero and postnatally. We review differences in the structure and function of the placenta in pregnancies complicated by fetal CHD and introduce the concept of a placental inefficiency phenotype that occurs in severe forms of fetal CHD, characterized by a myriad of pathologies. We propose that in CHD placental dysfunction contributes to decreased fetal cerebral oxygen delivery resulting in poor brain growth, brain abnormalities, and impaired neurodevelopment. We conclude the review with key areas for future research in neuroplacentology in the fetal CHD population, including (1) differences in structure and function of the CHD placenta, (2) modifiable and nonmodifiable factors that impact the hemodynamic balance between placental and cerebral circulations, (3) interventions to improve placental function and protect brain development in utero, and (4) the role of genetic and epigenetic influences on the placenta–heart–brain connection. Impact Neuroplacentology seeks to understand placental connections to fetal brain development. In fetuses with CHD, brain growth abnormalities begin in utero. Placental microstructure as well as perfusion and function are abnormal in fetal CHD.

Haemorheological Effects on Thrombocyte Adhesion and Aggregation Found Under Controlled Flow Conditions

1979 ◽  
Author(s):  
P.D. Richardson
Keyword(s):  
Rate Of Change ◽  
Continuous Observation ◽  
Flow Conditions ◽  
Wide Range ◽  
Stream Migration ◽  
Local Shear ◽  
Videotape Recording ◽  
Controlled Flow ◽  
A Site

Thrombocyte adhesion and aggregation in a vessel or on a chamber wall can be measured most readily if the flow is controlled and steady, and continuous observation is used. Videotape recording is very helpful for subsequent quantification of the dynamics. The adhesion of each thrombocyte can occur for a finite time interval:this interval has been observed to have a wide range. Platelets which escape often leave open a site which attracts other platelets preferentially. The rate of change of adhesion density (platelets/mm2) is affected by the local shear rate and the shear history upstream. Aggregation is affected similarly, and also proceeds with some platelet turnover. The role of erythrocytes in facilitating cross-stream migration of thrombocytes (which can enhance the growth rate of large thrombi) appears due in part to convective flow fields induced by the motion of erythrocytes in a shear flow, which can be demonstrated theoretically and experimentally. Observations of the phenomenlogy of adhesion and aggregation under controlled flow conditions and comparison with fLu id-dynamically based theory allows representation in terras of a small number of parameters with prospects of prediction of behaviour over a wide range of haemodynamic conditions; biochemical changes lead to changes in values of the parameters, so that activating agents and inhibiting agents modify values in different directions.

THE ROLE OF THE MOTHER IN 131I METABOLISM OF SUCKING AND WEANLING RATS

1965 ◽  
Vol 43 (3) ◽  
pp. 431-436 ◽  
Author(s):  
M. Samel ◽  
A. Caputa
Keyword(s):  
Urinary Bladder ◽  
In Utero ◽  
The State ◽  
Newborn Rats ◽  
Weanling Rats ◽  
Immature Rats ◽  
Other Substances ◽  
Old Rats

In newborn rats the mother provokes the emptying of the urinary bladder by stimulating the perineum with her tongue. The possibility that mothers may thereby ingest the urine of their young has been studied by means of 131I on nine litters of rats aged 10 to 29 days. The results indicate that a considerable quantity of 131I administered intraperitoneally to 10- and 18-day-old rats, which were then reunited with their mothers for 4 hours, reappears in the organism of uninjected nurslings after passing through the organism of the mother. The amount of 131I transferred from injected rats into the bodies of isolated uninjected rats of the same litter decreased during the period of weaning. The observed recirculation of 131I between immature rats and their mothers in both directions may represent a saving mechanism which might include several other substances and would compensate for their loss via the milk, and suggests a new aspect of maternal–neonatal interrelationship which appears as a continuation of the state existing in utero.

The Role of In Utero Disruption of Prefrontal Corticothalamic Circuitry in the Etiology of Schizophrenia

2021 ◽  
Vol 89 (9) ◽  
pp. S209
Author(s):  
Kartik Pattabiraman ◽  
Mikihito Shibata ◽  
Belen Lorente Galdos ◽  
David Andrijevic ◽  
Navjot Kaur ◽  
...  
Keyword(s):  
In Utero

Getting in synch: Unpacking the role of parent–child synchrony in the development of internalizing and externalizing behaviors

2021 ◽  
pp. 1-13
Author(s):  
Laura E. Quiñones-Camacho ◽  
Caroline P. Hoyniak ◽  
Lauren S. Wakschlag ◽  
Susan B. Perlman
Keyword(s):  
Externalizing Behaviors ◽  
Internalizing Behaviors ◽  
Rate Of Change ◽  
Positive Interactions ◽  
Protective Mechanism ◽  
Neural Synchrony ◽  
Internalizing And Externalizing Behaviors ◽  
Internalizing And Externalizing ◽  
Parent Child

Abstract While substantial research supports the role of parent–child interactions on the emergence of psychiatric symptoms, few studies have explored biological mechanisms for this association. The current study explored behavioral and neural parent–child synchronization during frustration and play as predictors of internalizing and externalizing behaviors across a span of 1.5 years. Parent–child dyads first came to the laboratory when the child was 4–5 years old and completed the Disruptive Behavior Diagnostic Observation Schedule: Biological Synchrony (DB-DOS: BioSync) task while functional near-infrared spectroscopy (fNIRS) data were recorded. Parents reported on their child's internalizing and externalizing behaviors using the Child Behavior Checklist (CBCL) four times over 1.5 years. Latent growth curve (LGC) modeling was conducted to assess neural and behavioral synchrony as predictors of internalizing and externalizing trajectories. Consistent with previous investigations in this age range, on average, internalizing and externalizing behaviors decreased over the four time points. Parent–child neural synchrony during a period of play predicted rate of change in internalizing but not externalizing behaviors such that higher parent–child neural synchrony was associated with a more rapid decrease in internalizing behaviors. Our results suggest that a parent–child dyad's ability to coordinate neural activation during positive interactions might serve as a protective mechanism in the context of internalizing behaviors.

Corticoids and Respiratory Distress

PEDIATRICS ◽  
1973 ◽  
Vol 51 (5) ◽  
pp. 955-956
Author(s):  
William W. Holm
Keyword(s):  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Distress Syndrome ◽  
Pulmonary Arteries ◽  
In Utero ◽  
Target Organ ◽  
Primary Target ◽  
Bronchial Arteries ◽  
Added Benefit

Liggins and Howie1 have demonstrated the effect of antepartum dexamethasone in the prevention of the respiratory distress syndrome (RDS). Contrary to the current concept2 that this prevention results from maturation of the lung, though this may be an added benefit, the writer proposes that the adrenal is the primary target organ. In a previous letter3 regarding the role of catecholamines in the etiology of RDS he advised that whereas the lung of the mature infant is perfused by the pulmonary arteries (inducing alveolar expansion),4 the lung of the infant in utero is perfused by the bronchial arteries (inducing atelectasis).4

scholarly journals Asynchronous globin chain synthesis in rabbit reticulocyte lystates induced by hemin-controlled repressor

Blood ◽  
1978 ◽  
Vol 51 (4) ◽  
pp. 653-658 ◽  
Author(s):  
RS Franco ◽  
JW Hogg ◽  
OJ Martelo
Keyword(s):  
Globin Chain ◽  
Free System ◽  
Globin Chains ◽  
Reticulocyte Lysate ◽  
Chain Imbalance ◽  
Globin Synthesis ◽  
Chain Synthesis ◽  
Globin Chain Synthesis

Abstract To define further the role of hemin-controlled repressor (HCR) in globin synthesis, we studied its effect on the synthesis of individual globin chains in a rabbit reticulocyte lysate cell-free system. In the presence of HCR there was a marked globin chain imbalance, resulting in a lowered alpha/beta ratio. These findings in vitro may have relevance to certain clinical heme deficiency states in which a similar globin chain imbalance has been observed.

scholarly journals A critical role of VLA-4 in erythropoiesis in vivo

Blood ◽  
1996 ◽  
Vol 87 (6) ◽  
pp. 2513-2517 ◽  
Author(s):  
K Hamamura ◽  
H Matsuda ◽  
Y Takeuchi ◽  
S Habu ◽  
H Yagita ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Fetal Liver ◽  
Critical Role ◽  
In Utero ◽  
In Vitro Studies ◽  
Specific Interactions ◽  
Erythroid Progenitors

Hematopoiesis requires specific interactions with the microenvironments, and VLA-4 has been implicated in these interactions based on in vitro studies. To study the role of VLA-4 in hematopoiesis in vivo, we performed in utero treatment of mice with an anti-VLA-4 monoclonal antibody. Although all hematopoietic cells in fetal liver expressed VLA-4, the treatment specifically induced anemia. It had no effect on the development of nonerythroid lineage cells, including lymphoids and myeloids. In the treated liver almost no erythroblast was detected, whereas the erythroid progenitors, which give rise to erythroid colonies in vitro, were present. These results indicate that VLA-4 plays a critical role in erythropoiesis, while it is not critical in lymphopoiesis in vivo.

Sign in / Sign up

Export Citation Format

Share Document