Placental restriction alters circulating thyroid hormone in the young lamb postnatally

2006 ◽  
Vol 291 (4) ◽  
pp. R1016-R1024 ◽  
Author(s):  
Miles J. De Blasio ◽  
Kathryn L. Gatford ◽  
Jeffrey S. Robinson ◽  
Julie A. Owens
Keyword(s):  
Thyroid Hormone ◽  
Growth Rates ◽  
Soft Tissues ◽  
Tissue Growth ◽  
Crown Rump Length ◽  
Absolute Growth ◽  
Catch Up ◽  
Accelerated Growth ◽  
Size At Birth ◽  
General Plasma

Intrauterine growth restriction (IUGR) is associated with accelerated growth and increased adiposity in early life due to unknown mechanisms, which could include increased thyroid hormone (TH) action. We hypothesized that placental restriction (PR) of fetal growth would increase circulating TH concentrations and alter their response to fasting, and that these would relate to growth and body composition in the young lamb. PR reduced size at birth, increased fractional growth rates (FGRs) of soft and skeletal tissues up to 30 days of age, and slowed the ontogenic decrease in plasma total T3 and plasma total T3/T4. PR did not alter the abundance of plasma THs after short-term fasting. In general, plasma total T3 and total T3/T4 ratio correlated negatively, whereas plasma total T4 correlated positively with size at birth. Absolute growth rates of weight and crown-rump length correlated positively with plasma total T3 and total T4 between days 15 and 35. Current FGRs for weight and metatarsal length correlated positively with plasma total T3 between days 20 and 35. In conclusion, PR and small size at birth reduce plasma total T4 and increase plasma total T3 postnatally, whereas catch-up growth relates to increased abundance of the more bioactive forms of TH. Finally, greater soft tissue growth occurs in PR compared with control lambs at the same circulating TH concentrations. This suggests that PR and small size at birth may increase activation of T4 to T3 and sensitivity of soft tissues to TH, which may contribute to catch-up growth following IUGR.

Placental restriction of fetal growth reduces size at birth and alters postnatal growth, feeding activity, and adiposity in the young lamb

2007 ◽  
Vol 292 (2) ◽  
pp. R875-R886 ◽  
Author(s):  
Miles J. De Blasio ◽  
Kathryn L. Gatford ◽  
Jeffrey S. Robinson ◽  
Julie A. Owens
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Feeding Activity ◽  
Later Life ◽  
Postnatal Growth ◽  
Postnatal Life ◽  
Absolute Growth ◽  
Accelerated Growth ◽  
Early Postnatal Life ◽  
Size At Birth

Intrauterine growth restriction (IUGR) is associated with accelerated growth after birth. Together, IUGR and accelerated growth after birth predict reduced lean tissue mass and increased obesity in later life. Although placental insufficiency is a major cause of IUGR, whether it alters growth and adiposity in early postnatal life is not known. We hypothesized that placental restriction (PR) in the sheep would reduce size at birth and increase postnatal growth rate, fat mass, and feeding activity in the young lamb. PR reduced survival rate and size at birth, with soft tissues reduced to a greater extent than skeletal tissues and relative sparing of head width ( P < 0.05 for all). PR did not alter absolute growth rates (i.e., the slope of the line of best fit for age vs. parameter size from birth to 45 days of age) but increased neonatal fractional growth rates (absolute growth rate relative to size at birth) for body weight (+24%), tibia (+15%) and metatarsal (+18%) lengths, hindlimb (+23%) and abdominal (+19%) circumferences, and fractional growth rates for current weight ( P < 0.05) weekly throughout the first 45 days of life. PR and small size at birth reduced individual skeletal muscle weights and increased visceral adiposity in absolute and relative terms. PR also altered feeding activity, which increased with decreasing size at birth and was predictive of increased postnatal growth and adiposity. In conclusion, PR reduced size at birth and induced catch-up growth postnatally, normalizing weight and length but increasing adiposity in early postnatal life. Increased feeding activity may contribute to these alterations in growth and body composition following prenatal restraint and, if they persist, may lead to adverse metabolic and cardiovascular outcomes in later life.

Spontaneous intrauterine growth restriction due to increased litter size in the guinea pig programmes postnatal growth, appetite and adult body composition

2016 ◽  
Vol 7 (5) ◽  
pp. 548-562 ◽  
Author(s):  
D. M. Horton ◽  
D. A. Saint ◽  
J. A. Owens ◽  
K. L. Kind ◽  
K. L. Gatford
Keyword(s):  
Body Composition ◽  
Guinea Pig ◽  
Growth Rates ◽  
Guinea Pigs ◽  
Intrauterine Growth Restriction ◽  
Intrauterine Growth ◽  
Adult Body ◽  
Catch Up ◽  
Neonatal Growth ◽  
Size At Birth

Intrauterine growth restriction (IUGR) and subsequent neonatal catch-up growth are implicated in the programming of increased appetite, adiposity and cardiometabolic diseases. Guinea pigs provide an alternate small animal model to rodents to investigate mechanisms underlying prenatal programming, being relatively precocial at birth, with smaller litter sizes and undergoing neonatal catch-up growth after IUGR. The current study, therefore, investigated postnatal consequences of spontaneous IUGR due to varying litter size in this species. Size at birth, neonatal, juvenile (post-weaning, 30–60 days) and adolescent (60–90 days) growth, juvenile and adolescent food intake, and body composition of young adults (120 days) were measured in 158 male and female guinea pigs from litter sizes of one to five pups. Compared with singleton pups, birth weight of pups from litters of five was reduced by 38%. Other birth size measures were reduced to lesser degrees with head dimensions being relatively conserved. Pups from larger litters had faster fractional neonatal growth and faster absolute and fractional juvenile growth rates (P<0.005 for all). Relationships of post-weaning growth, feed intakes and adult body composition with size at birth and neonatal growth rate were sex specific, with neonatal growth rates strongly and positively correlated with adiposity in males only. In conclusion, spontaneous IUGR due to large litter sizes in the guinea pig causes many of the programmed sequelae of IUGR reported in other species, including human. This may therefore be a useful model to investigate the mechanisms underpinning perinatal programming of hyperphagia, obesity and longer-term metabolic consequences.

Delayed transmission of a parasite is compensated by accelerated growth

Parasitology ◽  
2005 ◽  
Vol 131 (5) ◽  
pp. 647-656 ◽  
Author(s):  
T. HAKALAHTI ◽  
M. BANDILLA ◽  
E. T. VALTONEN
Keyword(s):  
Growth Rates ◽  
Free Living ◽  
Host Seeking ◽  
Age Dependent ◽  
Food Shortages ◽  
Catch Up ◽  
Argulus Coregoni ◽  
Accelerated Growth ◽  
Rates Of Growth ◽  
Delayed Growth

Compensatory or ‘catch-up’ growth following prolonged periods of food shortages is known to exist in many free-living animals. It is generally assumed that growth rates under normal circumstances are below maximum because elevated rates of growth are costly. The present paper gives experimental evidence that such compensatory growth mechanisms also exist in parasitic species. We explored the effect of periodic host unavailability on survival, infectivity and growth of the fish ectoparasiteArgulus coregoni. Survival and infectivity ofA. coregonimetanauplii deprived of a host for selected time periods were age dependent, which indicates that all metanauplii carry similar energy resources for host seeking. Following the periods off-host, metanauplii were allowed to settle on rainbow trout and were length measured until they reached gravidity. During early development on fish, body length of attachedA. coregoniwas negatively correlated with off-host period indicating a mechanism that creates size variance in an attached parasite cohort originally containing equal amounts of resources. However, over time the size differences between parasites became less pronounced and eventually parasites that were kept off-host for longest periods of time reached the length of those individuals that had been allowed to infect a host sooner.A. coregonithus appears to compensate for delayed growth resulting from an extended host searching period by elevated growth rates, although we show that such accelerated growth incurred a cost, through decreased life-expectancy.

scholarly journals Age, growth, and recruitment patterns of juvenile ladyfish (Elopssp) from the east coast of Florida (USA)

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1392
Author(s):  
Juan C. Levesque
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Age And Growth ◽  
Growth Equation ◽  
Length Frequency ◽  
Daily Growth ◽  
Exponential Regression ◽  
Absolute Growth ◽  
Specific Growth Rates ◽  
Size At Age

Ladyfish (Elopssp) are a common and economically valuable coastal nearshore species found along coastal beaches, bays, and estuaries of the southeastern United States, and subtropical and tropical regions worldwide. Previously, ladyfish were a substantial bycatch in Florida’s commercial fisheries, but changes in regulations significantly reduced commercial landings. Today, ladyfish are still taken in commercial fisheries in Florida, but many are also taken by recreational anglers. Life-history information and research interest in ladyfish is almost non-existent, especially information on age and growth. Thus, the overarching purpose of this study was to expand our understanding of ladyfish age and growth characteristics. The specific objectives were to describe, for the first time, age, growth, and recruitment patterns of juvenile ladyfish from the east coast of Florida (USA). In the Indian River Lagoon (IRL), annual monthly length-frequency distributions were confounded because a few small individuals recruited throughout the year; monthly length-frequency data generally demonstrated a cyclical pattern. The smallest were collected in September and the largest in May. Post-hoc analysis showed no significant difference in length between August and May, or among the other months. In Volusia County (VC), annual monthly length-frequency distribution demonstrated growth generally occurred from late-winter and spring to summer. The smallest ladyfish were collected in February and the largest in August. On average, the absolute growth rate in the IRL was 36.3 mm in 60 days or 0.605 mm day−1. Cohort-specific daily growth rates, elevations, and coincidentals were similar among sampling years. Cohort-specific growth rates ranged from 1.807 in 1993 to 1.811 mm day−1in 1994. Overall, growth was best (i.e., goodness of fit) described by exponential regression. On average, the absolute growth rate in VC was 28 mm in 150 days or 0.1866 mm day−1. Cohort-specific daily growth rates were significantly different among sampling years; however, the elevations and coincidentals were similar. Cohort-specific growth rates ranged from 1.741 in 1994 to 1.933 mm day−1in 1993. Mean ladyfish growth was best described by linear regression; however, natural growth was explained better by exponential regression. In the IRL, the corrected exponential growth equation yielded a size-at-age 1 of 156.0 mm SL, which corresponded to an estimated growth rate of 0.4356 mm day−1. In VC, the corrected exponential growth equation yielded a size-at-age 1 of 80 mm SL corresponding to an estimated growth rate of 0.2361 mm day−1.

scholarly journals Thyroid Hormones and Peripheral Nerve Regeneration

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Ioannis D. Papakostas ◽  
George A. Macheras
Keyword(s):  
Thyroid Hormone ◽  
Peripheral Nerve ◽  
Nerve Regeneration ◽  
Intracellular Signaling ◽  
Peripheral Nerve Regeneration ◽  
Tissue Growth ◽  
Tissue Response ◽  
Cell Integrity ◽  
Neuronal Soma ◽  
Insight Into

Peripheral nerve regeneration is a unique process in which cellular rather than tissue response is involved. Depending on the extent and proximity of the lesion and the age and type of the neuronal soma, the cell body may either initiate a reparative response or may die. Microsurgical intervention may alter the prognosis after a peripheral nerve injury but to a certain extent. By altering the biochemical microenvironment of the neuron, we can increase the proportion of neurons that survive the injury and initiate the reparative response. Thyroid hormone critically regulates tissue growth and differentiation and plays a crucial role during organ development. Furthermore, recent research has provided new insight into thyroid hormone cellular action. Thyroid hormone regulates stress response intracellular signaling and targets molecules important for cytoskeletal stability and cell integrity. Changes in thyroid hormone signaling occur in nerve and other tissues, with important physiological consequences. The interest in thyroid hormone in the context of nerve regeneration has recently been revived.

Mandibular Catch-Up Growth in Pierre Robin Sequence: A Systematic Review

2018 ◽  
Vol 56 (2) ◽  
pp. 168-176 ◽  
Author(s):  
Chad A. Purnell ◽  
Lindsay E. Janes ◽  
Julian L. Klosowiak ◽  
Arun K. Gosain
Keyword(s):  
Systematic Review ◽  
Growth Rates ◽  
English Literature ◽  
Pierre Robin Sequence ◽  
Cross Sectional ◽  
Mandibular Growth ◽  
Gonial Angle ◽  
Robin Sequence ◽  
Catch Up ◽  
Pierre Robin

Objective: The concept of mandibular catch-up growth is often quoted in the literature regarding Pierre Robin sequence (PRS). We endeavored to perform a systematic review of whether the literature supports this concept. Design: Systematic review. Interventions: A PubMed-based systematic review of the English literature was performed of articles objectively measuring mandibular growth or position after nonoperative management of PRS. Main Outcome Measures: Rate and end point of mandibular length, ramus length, gonial angle, and maxillomandibular discrepancy. Results: The initial search delivered 607 English-language abstracts. Of these, 16 met inclusion criteria. Eight articles evaluating 143 patients followed longitudinal patient data and therefore allowed comparison of growth rates to controls. Ten articles evaluating 228 patients presented cross-sectional data and therefore could only evaluate a single time point. Two of the 8 longitudinal studies reported faster than normal growth of mandibular length in a significant portion of their cohort. Five of 8 reported equal growth rates. One of 16 studies reported that mandibular length of patients with PRS normalized compared to controls. Two of 16 studies reported no difference in maxillomandibular discrepancy between PRS and controls, whereas 10 reported a posteriorly displaced mandible relative to the maxilla in PRS. Significant differences in control groups, patients, and age existed between studies. Conclusions: While the concept of catch-up growth in PRS is often quoted, a minority of objective studies suggest increased mandibular growth rates in isolated PRS. Even fewer studies suggest that the maxillomandibular discrepancy in PRS completely resolves.

Compact Two Degrees-of-Freedom External Fixator System for Correction of Persistent Clubfoot Deformity

2019 ◽  
Vol 13 (2) ◽  
Author(s):  
Ying Ying Wu ◽  
Anton Plakseychuk ◽  
Kenji Shimada
Keyword(s):  
External Fixator ◽  
Degrees Of Freedom ◽  
Soft Tissues ◽  
Three Dimensional ◽  
Deformity Correction ◽  
Current Method ◽  
Tissue Growth ◽  
Learning Curves ◽  
Patient Specific ◽  
Two Degrees Of Freedom

Bone deformities are often complex three-dimensional (3D) deformities, and correcting them is difficult. To correct persistent clubfoot deformity in adolescents or adults, an external fixator is sometimes used to encourage tissue growth and preserve healthy tissues. However, it is difficult to set up, resulting in long surgeries and steep learning curves for surgeons. It is also bulky and obstructs patient mobility. In this paper, we introduce a new approach of defining clubfoot deformity correction as a six degrees-of-freedom (6DOF) correction, and then reducing it to just two degrees-of-freedom (2DOF) using the axis-angle representation. Therefore, only two physical trajectory joints are needed, which in turn enables a more compact fixator design. A computer planner was developed to minimize the bulk of the external fixator, and to optimize the distraction schedule to avoid overstretching the soft tissues. This reduces the learning curve for surgeons and shortens surgery time. To validate the system, a patient-specific clubfoot simulator was developed, and four experiments were performed on the clubfoot simulator. The accuracy of midfoot correction was 11 mm and 3.5 deg without loading, and 41 mm and 11.7 deg with loading. While the external fixator has to be more rigid to overcome resistance against correction, the surgical system itself was able to achieve accurate correction in less than 2 h. This is an improvement from the current method, which takes 2.5–4.5 h.

Growth and Development of Pouch Young of Wild and Captive Dasyurus-Geoffroii (Marsupialia, Dasyuridae)

1988 ◽  
Vol 36 (5) ◽  
pp. 533 ◽  
Author(s):  
M Serena ◽  
TR Soderquist
Keyword(s):  
Growth Rates ◽  
Growth And Development ◽  
Head Width ◽  
Square Root ◽  
Crown Rump Length ◽  
Medium Weight

Growth and development of six captive litters of D. geoffroii were monitored at 1-5 day intervals from birth until they were left in dens at about 62-72 days of age. Two neonates were 4.4 mm long and weighed an average 11 mg. By the age of 63 days, juvenile weight had increased 1500-fold, to an average of 16.7 g. Growth of crown-rump length (from 0-40 days) and the square root of head width (from 8-65 days) is linear with respect to time. Wild D. geoffroii were first observed to be left in dens at the age of 62 days, soon after outgrowing the pouch. Wild and captive growth rates appear similar through the first half of pouch life. At older ages, wild litters generally grew more slowly than captive litters; wild litters belonging to thin mothers grew more slowly than litters with medium-weight mothers, which in turn grew more slowly than litters with fat mothers.

Sign in / Sign up

Export Citation Format

Share Document