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Journal of Animal Science and... 2015Many advances in genetic selection, nutrition, housing and disease control have been incorporated into modern pork production since the 1950s resulting in highly... (Review)
Review
Many advances in genetic selection, nutrition, housing and disease control have been incorporated into modern pork production since the 1950s resulting in highly prolific females and practices and technologies, which significantly increased efficiency of reproduction in the breeding herd. The objective of this manuscript is to review the literature and current industry practices employed for reproductive management. In particular the authors focus on assisted reproduction technologies and their application for enhanced productivity. Modern maternal line genotypes have lower appetites and exceptional lean growth potential compared to females of 20 yr ago. Thus, nutrient requirements and management techniques and technologies, which affect gilt development and sow longevity, require continuous updating. Failure to detect estrus accurately has the greatest impact on farrowing rate and litter size. Yet, even accurate estrus detection will not compensate for the variability in the interval between onset of estrus and actual time of ovulation. However, administration of GnRH analogs in weaned sows and in gilts after withdrawal of altrenogest do overcome this variability and thereby synchronize ovulation, which makes fixed-time AI practical. Seasonal infertility, mediated by temperature and photoperiod, is a persistent problem. Training workers in the art of stockmanship is of increasing importance as consumers become more interested in humane animal care. Altrenogest, is used to synchronize the estrous cycle of gilts, to prolong gestation for 2-3 d to synchronize farrowing and to postpone post-weaning estrus. P.G. 600® is used for induction of estrus in pre-pubertal gilts and as a treatment to overcome seasonal anestrous. Sperm cell numbers/dose of semen is significantly less for post cervical AI than for cervical AI. Real-time ultrasonography is used to determine pregnancy during wk 3-5. PGF2α effectively induces farrowing when administered within two d of normal gestation length. Ovulation synchronization, single fixed-time AI and induced parturition may lead to farrowing synchronization, which facilitates supervision and reduces stillbirths and piglet mortality. Attendance and assistance at farrowing is important especially to ensure adequate colostrum consumption by piglets immediately after birth. New performance terminologies are presented.
PubMed: 25838898
DOI: 10.1186/2049-1891-6-3 -
American Journal of Physiology. Renal... Oct 2002Puberty accelerates microvascular complications of diabetes mellitus, including nephropathy. Animal studies confirm a different renal hypertrophic response to diabetes... (Review)
Review
Puberty accelerates microvascular complications of diabetes mellitus, including nephropathy. Animal studies confirm a different renal hypertrophic response to diabetes before and after puberty, probably due to differences in the production of transforming growth factor-beta (TGF-beta). Many of the complex physiological changes during puberty could affect potentially pathogenic mechanisms of diabetic kidney disease. Increased blood pressure, activation of the growth hormone-insulin-like growth factor I axis, and production of sex steroids could all play a role in pubertal susceptibility to diabetic renal hypertrophy and nephropathy. These factors may influence the effects of hyperglycemia and several systems that ultimately control TGF-beta production, including the renin-angiotensin system, cellular redox systems, the polyol pathway, and protein kinase C. These phenomena may also explain gender differences in kidney function and incidence of end-stage renal disease. Normal changes during puberty, when coupled with diabetes and superimposed on a genetically susceptible milieu, are capable of accelerating diabetic hypertrophy and microvascular lesions. A better understanding of these processes may lead to new treatments to prevent renal failure in diabetes mellitus.
Topics: Adolescent; Diabetic Nephropathies; Female; Gonadal Steroid Hormones; Humans; Kidney; Male; Puberty
PubMed: 12217849
DOI: 10.1152/ajprenal.00368.2001 -
Endocrinology, Diabetes & Metabolism... 2016Estrogen is used to induce puberty in peripubertal girls with hypogonadism. Although both synthetic and natural forms are available, along with different routes of...
UNLABELLED
Estrogen is used to induce puberty in peripubertal girls with hypogonadism. Although both synthetic and natural forms are available, along with different routes of administration, in the UK oral ethinyl estradiol and the low-dose oral contraceptive pill are commonly used as hormone replacement therapy for practical reasons. We present five peripubertal girls (aged 12.5-14.9 years) with hypogonadism (two with primary hypogonadism due to Turner syndrome and three with central (secondary) hypogonadism as part of multiple pituitary hormone deficiency) who for a variety of reasons have received milligram doses of estradiol (E2) in error for between 6 weeks and 6 months, instead of the expected microgram doses of ethinyl estradiol. Although there are no direct comparisons in peripubertal girls between synthetic and natural estrogens, all girls had vaginal bleeding whilst receiving the milligram doses and have ended up with reduced final heights, below the 9th centile in 1 and below the 2nd centile in 4. Whilst reduction in final height may be part of the underlying condition (especially in Turner syndrome) the two girls with height predictions performed prior to receiving the estrogen overdose have not achieved their predicted height. Estrogen is one of the few drugs which is available in both milligram and microgram formulations. Clinicians need to be alert to the possibility of patients receiving the wrong formulation and dosage in error.
LEARNING POINTS
Girls with primary and secondary gonadal failure require assistance with pubertal induction.Although several different formulations and route of administration are available, for practical reasons, the majority of girls in the UK receive oral ethinyl estradiol.Estrogen preparations are available in both milligram and microgram formulations, with potential for receiving the wrong dose.Girls receiving milligram rather than microgram preparations all had vaginal bleeding and a short final height.
PubMed: 26843960
DOI: 10.1530/EDM-15-0096 -
Archives of Disease in Childhood Jan 2004Asthma has little, if any, significant effect on attained adult height. Untreated asthma results in a delay of puberty by approximately 1.3 years, and pubertal delay is... (Review)
Review
Asthma has little, if any, significant effect on attained adult height. Untreated asthma results in a delay of puberty by approximately 1.3 years, and pubertal delay is likely to explain the majority of apparent growth failure in asthmatics. All currently available inhaled corticosteroids (ICS) result in growth suppression at conventional doses (400 microg/day of beclomethasone dipropionate equivalent), but the growth suppressive effects are relatively short lived, after which growth reverts to pretreatment levels. Younger, prepubertal children, appear more sensitive to the growth suppressive effects of ICS. Asthmatic children receiving conventional doses of ICS (400 microg/day of BDP equivalent) will attain an adult height indistinguishable from their predicted adult height (based on their mid parental height), and no different from non-asthmatics. Adult height could possibly be decreased in severe asthmatics, but this is unlikely to be greater than a 1.2 cm decrement. Recent longitudinal studies offer reassurance that at conventional doses ICS do not have significant long term effects on growth, and that their benefits consistently outweigh their side effects.
Topics: Administration, Inhalation; Adrenal Cortex Hormones; Adult; Anti-Asthmatic Agents; Asthma; Body Height; Child; Growth Disorders; Humans; Puberty
PubMed: 14709510
DOI: 10.1136/adc.2003.014365 -
Frontiers in Endocrinology 2023Impaired testosterone secretion is a frequent following hematopoietic stem cell transplantation (HSCT) in pediatrics, but long-term longitudinal trendlines of clinical...
INTRODUCTION
Impaired testosterone secretion is a frequent following hematopoietic stem cell transplantation (HSCT) in pediatrics, but long-term longitudinal trendlines of clinical and biochemical findings are still scanty.
METHODS
Monocentric, retrospective analysis. Male patients transplanted <18 years between 1992 and 2021, surviving ≥2 years after HSCT and showing, upon enrollment, clinical and biochemical signs consistent with pubertal onset and progression were included. Clinical and biochemical data collected every 6-12 months were recorded.
RESULTS
Of 130 patients enrolled, 56% were prepubertal, while 44% were peri-/postpubertal upon HSCT. Overall, 44% showed spontaneous progression into puberty and normal gonadal profile, while the remaining experienced pubertal arrest (1%), isolated increase of FSH (19%), compensated (23%) or overt (13%) hypergonadotropic hypogonadism. Post-pubertal testicular volume (TV) was statistically smaller among patients still pre-pubertal upon HSCT ( 0.049), whereas no differences were recorded in adult testosterone levels. LH and testosterone levels showed a specular trend between 20 and 30 years, as a progressive decrease in sexual steroids was associated with a compensatory increase of the luteinizing hormone. A variable degree of gonadal dysfunction was reported in 85%, 51%, 32% and 0% of patients following total body irradiation- (TBI), busulfan-, cyclophosphamide- and treosulfan-based regimens, respectively. TBI and busulfan cohorts were associated with the lowest probability of gonadal event-free course (<0.0001), while it achieved 100% following treosulfan. A statistically greater gonadotoxicity was detected after busulfan than treosulfan ( 0.024). Chemo-only regimens were associated with statistically larger TV (0.001), higher testosterone ( 0.008) and lower gonadotropin levels (0.001) than TBI. Accordingly, the latter was associated with a 2-fold increase in the risk of gonadal failure compared to busulfan (OR 2.34, CI 1.08-8.40), whereas being pre-pubertal upon HSCT was associated with a reduced risk (OR 0.15, CI 0.08-0.30).
CONCLUSIONS
a) patients pre-pubertal upon HSCT showed a reduced risk of testicular endocrine dysfunction, despite smaller adult TV; b) patients showed downwards trend in testosterone levels after full pubertal attainment, despite a compensatory increase in LH; c) treosulfan was associated to a statistically lower occurrence of hypogonadism than busulfan, with a trend towards larger TV, higher testosterone levels and lower gonadotropins.
Topics: Adult; Child; Humans; Male; Busulfan; Leydig Cells; Retrospective Studies; Hypogonadism; Hematopoietic Stem Cell Transplantation; Testosterone
PubMed: 38152128
DOI: 10.3389/fendo.2023.1292683 -
International Journal of Molecular... Nov 2021Although the cancer survival rate has increased, cancer treatments, including chemotherapy and radiotherapy, can cause ovarian failure and infertility in women of... (Review)
Review
Although the cancer survival rate has increased, cancer treatments, including chemotherapy and radiotherapy, can cause ovarian failure and infertility in women of reproductive age. Preserving fertility throughout cancer treatment is critical for maintaining quality of life. Fertility experts should propose individualized fertility preservation methods based on the patient's marital status, pubertal status, partner status, and the urgency of treatment. Widely practiced fertility preservation methods, including ovarian transposition and embryo and oocyte cryopreservation, are inappropriate for prepubertal girls or those needing urgent initiation of cancer treatment. Ovarian tissue cryopreservation and transplantation, an emerging new technology, may be a solution for these cancer patients. The use of stem cells in ovarian tissue cryopreservation and transplantation increases oxygenation, angiogenesis, and follicle survival rates. This review discusses the recent advances in ovarian tissue cryopreservation and transplantation with special focus on the use of stem cells to improve fertilization techniques.
Topics: Cryopreservation; Female; Fertility Preservation; Humans; Oocytes; Ovarian Follicle; Primary Ovarian Insufficiency; Stem Cell Transplantation; Stem Cells
PubMed: 34830363
DOI: 10.3390/ijms222212482 -
Endocrinology, Diabetes & Metabolism... 2017This case, presenting with bilateral impalpable testes, illustrates the relevance of a broad differential disorders of sex development case management. It provides new...
SUMMARY
This case, presenting with bilateral impalpable testes, illustrates the relevance of a broad differential disorders of sex development case management. It provides new insights on hypothalamic-pituitary-gonadal (HPG) axis and testicular function abnormalities in the multisystem disorder of Lowe syndrome. Lowe syndrome, also known as oculocerebrorenal syndrome, is a rare disorder characterised by eye abnormalities, central nervous system involvement and proximal renal tubular acidosis. There are a handful of reports of pubertal delay, infertility and cryptorchidism in Lowe syndrome. Biochemistry aged 72 h: testosterone 6.4 nmol/L, LH <0.5 IU/L and FSH <0.5 IU/L. Gonadotropin-releasing hormone stimulation test identified significantly raised baseline LH = 45.4 IU/L (contrasts with earlier undetectable LH), with a 20% increase on stimulation, while baseline FSH = 4.3 IU/L with no increase on stimulation. Day 14 HCG stimulation test produced an acceptable 50% increase in testosterone. The constellation of further abnormalities suggested Lowe syndrome: hypotonia, bilateral cataracts (surgical extraction and intraocular lens implantation) and renal tubular acidosis (microscopic haematuria, hypercalciuria, proteinuria, generalised aminoaciduria, hypophosphataemia and metabolic acidosis). DNA sequencing identified hemizygous frameshift mutation OCRL c.2409_2410delCT in exon 22. Interpretation of initial and repeat GnRH and HCG testing indicates the likelihood of testicular failure. Partial testicular descent occurred but left orchidopexy was required. Improving long-term gonadal function in Lowe syndrome assumes increased importance for current cohorts as advances in renal replacement therapy have greatly improved life expectancy. Noting HPG axis abnormalities in Lowe syndrome in infancy can identify cases requiring increased surveillance of pubertal progress for earlier detection and management.
LEARNING POINTS
Clinical endocrine problems in Lowe syndrome has been reported, but has focused on abnormalities in adolescence and young adulthood: pubertal delay and infertility.We present an infant with isolated LH elevation at baseline and on GnRH stimulation testing who also had bilateral impalpable testes.Early testing of the HPG axis in patients with Lowe syndrome may help predict gonadal abnormalities from a younger age, which will enhance the overall case management into adolescence.
PubMed: 28469921
DOI: 10.1530/EDM-17-0042 -
Jornal de Pediatria 2019To discuss the etiology and growth consequences of small size at birth and the indications, effects, and safety of biosynthetic growth hormone therapy in children born... (Review)
Review
OBJECTIVES
To discuss the etiology and growth consequences of small size at birth and the indications, effects, and safety of biosynthetic growth hormone therapy in children born small for gestational age.
SOURCE OF DATA
A comprehensive and non-systematic search was carried out in the PubMed, LILACS, and SciELO databases from 1980 to the present day, using the terms "small for gestational age," "intrauterine growth restriction," and "growth hormone". The publications were critically selected by the authors.
DATA SYNTHESIS
Although the majority of children born small for gestational age show spontaneous catch-up growth during the first two years of life, some of them remain with short stature during childhood, with high risk of short stature in adult life. Treatment with growth hormone might be indicated, preferably after 2-4 years of age, in those small for gestational age children who remain short, without catch-up growth. Treatment aims to increase growth velocity and to reach a normal height during childhood and an adult height within target height. Response to growth hormone treatment is variable, with better growth response during the pre-pubertal period.
CONCLUSIONS
Treatment with growth hormone in short children born small for gestational age is safe and effective to improve adult height. Efforts should be done to identify the etiology of small size at birth before treatment.
Topics: Child Development; Female; Growth Disorders; Growth Hormone; Humans; Infant, Newborn; Infant, Small for Gestational Age
PubMed: 30550759
DOI: 10.1016/j.jped.2018.10.015 -
Transactions of the American Clinical... 1993The data reviewed in this chapter provide evidence that the pattern of GnRH secretion appears to be an important factor in regulating gonadotropin subunit gene... (Review)
Review
The data reviewed in this chapter provide evidence that the pattern of GnRH secretion appears to be an important factor in regulating gonadotropin subunit gene expression, gonadotropin synthesis and hormone secretion. The data on gonadotropin synthesis were obtained in rodents and hence, must be interpreted with caution when applied to primates. Despite this reservation, the data suggest a similarity of regulatory mechanisms in mammalian species. The data also provide an explanation for the mechanisms whereby a single gonadotropin-releasing hormone can differentially regulate the three gonadotropin genes and allow differential hormone secretion. In overall agreement with this view, the observations during pubertal maturation reveal increasing GnRH pulsatile secretion during puberty with an evolution from predominant FSH to a predominant LH secretion by the gonadotropes. In males, the patterns of GnRH secretion appear to be fairly consistent throughout adult life, but in women cyclic changes occur which perhaps are important in maintaining cyclic ovulation. It is proposed that once pubertal maturation has been established, GnRH is secreted at a relatively fast frequency (one pulse per hour), and an essential feature of repeated ovulatory cycles is the slowing of this GnRH stimulus during the luteal phase: to allow subsequent preferential FSH release. This slowing of GnRH secretion appears to be effected by estradiol and progesterone acting to enhance hypothalamic opioid activity. Similar mechanisms involving increased opioid tone appear to be causally related to the reduced frequency and irregular GnRH stimulus seen in hypothalamic amenorrhea and hyperprolactinemia. In contrast, some forms of polycystic ovarian disease may reflect abnormalities of the estradiol-progesterone/opioid/GnRH neuron feedback mechanisms, with failure to establish slowing in the peripubertal anovulatory cycles. The resulting persistent GnRH stimulus increases LH with consequent effects of abnormal follicular maturation and enhanced ovarian androgen production. Present data are supportive of these hypotheses, but future studies will determine whether these views prove to be correct. However, current data provide strong support for the view that the pattern of GnRH secretion is a critical factor in the regulation of differential gonadotropin synthesis and secretion in mammalian species.
Topics: Animals; Anovulation; Female; Follicle Stimulating Hormone; Gene Expression Regulation; Gonadotropin-Releasing Hormone; Humans; Luteinizing Hormone; Male; Menstrual Cycle; Puberty; Rats; Reproduction
PubMed: 1343446
DOI: No ID Found -
Frontiers in Endocrinology 2014The neuroendocrine control of reproduction in mammals is governed by a neural hypothalamic network of nearly 1500 gonadotropin-releasing hormone (GnRH) secreting neurons... (Review)
Review
The neuroendocrine control of reproduction in mammals is governed by a neural hypothalamic network of nearly 1500 gonadotropin-releasing hormone (GnRH) secreting neurons that modulate the activity of the reproductive axis across life. Congenital hypogonadotropic hypogonadism (HH) is a clinical syndrome that is characterized by partial or complete pubertal failure. HH may result from inadequate hypothalamic GnRH axis activation, or a failure of pituitary gonadotropin secretion/effects. In man, several genes that participate in olfactory and GnRH neuronal migration are thought to interact during the embryonic life. A growing number of mutations in different genes are responsible for congenital HH. Based on the presence or absence of olfaction dysfunction, HH is divided in two syndromes: HH with olfactory alterations [Kallmann syndrome (KS)] and idiopathic hypogonadotropic hypogonadism (IHH) with normal smell (normosmic IHH). KS is a heterogeneous disorder affecting 1 in 5000 males, with a three to fivefold of males over females. KS is associated with mutations in KAL1, FGFR1/FGF8, FGF17, IL17RD, PROK2/PROKR2, NELF, CHD7, HS6ST1, FLRT3, SPRY4, DUSP6, SEMA3A, NELF, and WDR11 genes that are related to defects in neuronal migration. These reproductive and olfactory deficits include a variable non-reproductive phenotype, including sensorineural deafness, coloboma, bimanual synkinesis, craniofacial abnormalities, and/or renal agenesis. Interestingly, defects in PROKR2, FGFR1, FGF8, CHD7, DUSP6, and WDR11 genes are also associated with normosmic IHH, whereas mutations in KISS1/KISSR, TAC3/TACR3, GNRH1/GNRHR, LEP/LEPR, HESX1, FSHB, and LHB are only present in patients with normosmic IHH. In this paper, we summarize the reproductive, neurodevelopmental, and genetic aspects of HH in human pathology.
PubMed: 25071724
DOI: 10.3389/fendo.2014.00109