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1.
Sci Rep ; 14(1): 7537, 2024 03 30.
Article in English | MEDLINE | ID: mdl-38553523

ABSTRACT

The aims of the study were: 1) to evaluate the changes in anthropometric variables, body composition, somatotype and body proportions of elite basketball players throughout the pre-season period; 2) to evaluate the changes in anthropometric variables, body composition, somatotype and body proportions of elite basketball players throughout the in-season period; and 3) to observe if the age and position influenced the variables analyzed. A total of 17 players belonging to the men's ACB league team competing in the Euroleague (age = 23.42 ± 5.28 years-old) participated in the study. The players underwent an anthropometric measurement before and after the pre-season, as well as four evaluations throughout the in-season. Anthropometric indices, somatotype components according to Heath and Carter, and adiposity were calculated. The results show that during the pre-season, body mass, BMI, sum of 6 and 8 skinfolds, waist/hip ratio, adipose tissue (kg), adipose tissue percentage, and endomorphy decreased, while ectomorphy increased. However, no significant changes were found in the variables analyzed throughout the season; except for endomorphy, which increased along the in-season. Playing position and age did not have a significant influence on the changes in the anthropometric variables throughout the pre-season and the in-season. In conclusion, while changes in the anthropometric variables in the pre-season were observed, these remained the same during the in-season.


Subject(s)
Basketball , Male , Humans , Adolescent , Young Adult , Adult , Somatotypes , Seasons , Body Height , Anthropometry , Body Composition
2.
Bull Entomol Res ; 109(2): 141-149, 2019 Apr.
Article in English | MEDLINE | ID: mdl-29665874

ABSTRACT

Accidental and intentional global movement of species has increased the frequency of novel plant-insect interactions. In Patagonia, the European woodwasp, Sirex noctilio, has invaded commercial plantations of North American pines. We compared the patterns of resin defenses and S. noctilio-caused mortality at two mixed-species forests near San Carlos de Bariloche, Argentina. We observed lower levels of resin flow and higher levels of mortality in Pinus contorta compared with Pinus ponderosa. In general, S. noctilio attacked trees with lower resin compared with neighboring trees. Resin production in P. ponderosa was not related to growth rates, but for P. contorta, slower growing trees produced less resin than faster growing conspecifics. For all infested trees, attack density and number of drills (ovipositor probes) per attack did not vary with resin production. Most attacks resulted in one or two drills. Attack rates and drills/attack were basically uniform across the bole of the tree except for a decrease in both drills/attack and attack density in the upper portion of the crown, and an increase in the attack density for the bottom 10% of the tree. Planted pines in Patagonia grow faster than their counterparts in North America, and produce less resin, consistent with the growth-differentiation balance hypothesis. Limited resin defenses may help to explain the high susceptibility of P. contorta to woodwasps in Patagonia.


Subject(s)
Hymenoptera , Pinus ponderosa/metabolism , Resins, Plant/metabolism , Animals , Behavior, Animal
3.
J Comp Physiol B ; 188(1): 57-76, 2018 01.
Article in English | MEDLINE | ID: mdl-28691154

ABSTRACT

In Sepia officinalis (Linnaeus, 1758), the digestive gland matures during the first month post-hatching, while a shift from intracellular acid to extracellular alkaline digestion occurs. The purpose of this study was to investigate the possibility of using enzymatic ratios for the description of digestive system maturation in early life stages of S. officinalis. Second, it is intended to apply these new tools as eco-physiological indicators for understanding the impact of cuttlefish eggs' life history from different spawning sites of the English Channel on digestive performance of juveniles. An experimental rearing was performed over 35 days after hatching (DAH) on juveniles from wild collected eggs in 2010 and 2011. Four digestive enzyme activities and their ratios [i.e., trypsin, cathepsin, acid (ACP), and alkaline (ALP) phosphatase, ALP/ACP, and trypsin/cathepsin] were studied along with histological features (e.g., internal yolk surface and digestive gland development). The two enzyme ratios were good indicators of digestive system maturation allowing the study of the digestive gland's development. They were highly correlated to juveniles' weight increase and histological features of the gland in early DAH. These ratios described more accurately the shift occurring between the intracellular acid and the extracellular alkaline modes of digestion in S. officinalis and were more specific than separated enzyme activities. Their application as eco-physiological tools revealed that enzyme ratios reflected yolk content and digestive gland development in new hatching juveniles. Finally, ALP/ACP ratio was shown to be a powerful tool to describe growth performance of S. officinalis which is useful for aquaculture optimization.


Subject(s)
Gastrointestinal Tract/physiology , Sepia/physiology , Acid Phosphatase , Alkaline Phosphatase , Animals , Aquaculture , Cathepsins , Gastrointestinal Tract/anatomy & histology , Sepia/anatomy & histology , Trypsin
4.
Phys Rev E ; 93(5): 052116, 2016 05.
Article in English | MEDLINE | ID: mdl-27300839

ABSTRACT

We develop an approach for performing scaling analysis of N-step random walks (RWs). The mean square end-to-end distance, 〈R[over ⃗]_{N}^{2}〉, is written in terms of inner persistence lengths (IPLs), which we define by the ensemble averages of dot products between the walker's position and displacement vectors, at the jth step. For RW models statistically invariant under orthogonal transformations, we analytically introduce a relation between 〈R[over ⃗]_{N}^{2}〉 and the persistence length, λ_{N}, which is defined as the mean end-to-end vector projection in the first step direction. For self-avoiding walks (SAWs) on 2D and 3D lattices we introduce a series expansion for λ_{N}, and by Monte Carlo simulations we find that λ_{∞} is equal to a constant; the scaling corrections for λ_{N} can be second- and higher-order corrections to scaling for 〈R[over ⃗]_{N}^{2}〉. Building SAWs with typically 100 steps, we estimate the exponents ν_{0} and Δ_{1} from the IPL behavior as function of j. The obtained results are in excellent agreement with those in the literature. This shows that only an ensemble of paths with the same length is sufficient for determining the scaling behavior of 〈R[over ⃗]_{N}^{2}〉, being that the whole information needed is contained in the inner part of the paths.

6.
Vet Pathol ; 53(4): 781-7, 2016 07.
Article in English | MEDLINE | ID: mdl-26926085

ABSTRACT

Osteosarcoma (OSA) is a malignant heterogeneous primary bone tumor responsible for up to 90% of all primary bone tumors in dogs. In this study, osteocalcin (OC) and osteonectin (ON) immunoreactivity was evaluated in 23 canine OSAs, 4 chondrosarcomas, 4 fibrosarcomas, 2 hemangiosarcomas, and 4 histiocytic sarcomas. The effects of three different decalcification agents (ethylenediaminetetraetic acid [EDTA], formic acid and hydrochloric acid [HCl]) on the immunoreactivity for OC and ON was also assessed. Immunoreactivity to OC was present in 19/23 (83%) cases of OSA and all cases of chondrosarcoma. In three OSAs the extracellular matrix showed immunoreactivity to OC. None of the fibrosarcomas, histiocytic sarcomas or hemangiosarcomas showed immunoreactivity to OC. The sensitivity and specificity for OC in canine OSA in this study was 83% and 71% respectively. For ON, 100% of both OSAs (23/23) and non-OSAs (14/14) showed cytoplasmic immunoreactivity to this antibody, giving a sensitivity of 100% but a complete lack of specificity. There were no significant differences in immunoreactivity for OC and ON between the different decalcification agents used. In conclusion, OC showed high sensitivity for identifying OSA but it failed to distinguish between OSA and chondrosarcoma, and the osteoid produced by neoplastic cells in most cases did not show immunoreactivity to OC. These factors may limit the practical utility of OC in the diagnosis of OSA in dogs when chondrosarcoma is a differential diagnosis. ON showed no specificity in detecting OSA and has little practical application for the diagnosis of OSA in dogs.


Subject(s)
Biomarkers, Tumor/metabolism , Dog Diseases/diagnosis , Osteocalcin/metabolism , Osteonectin/metabolism , Osteosarcoma/veterinary , Sarcoma/veterinary , Animals , Antibodies , Bone Neoplasms/diagnosis , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Bone Neoplasms/veterinary , Bone and Bones/metabolism , Bone and Bones/pathology , Chondrosarcoma/diagnosis , Chondrosarcoma/metabolism , Chondrosarcoma/pathology , Chondrosarcoma/veterinary , Diagnosis, Differential , Dog Diseases/metabolism , Dog Diseases/pathology , Dogs , Extracellular Matrix/metabolism , Fibrosarcoma/diagnosis , Fibrosarcoma/metabolism , Fibrosarcoma/pathology , Fibrosarcoma/veterinary , Hemangiosarcoma/diagnosis , Hemangiosarcoma/metabolism , Hemangiosarcoma/pathology , Hemangiosarcoma/veterinary , Histiocytic Sarcoma/diagnosis , Histiocytic Sarcoma/metabolism , Histiocytic Sarcoma/pathology , Histiocytic Sarcoma/veterinary , Immunohistochemistry/veterinary , Osteosarcoma/diagnosis , Osteosarcoma/metabolism , Osteosarcoma/pathology , Sarcoma/diagnosis , Sarcoma/metabolism , Sarcoma/pathology , Sensitivity and Specificity
7.
Appl Radiat Isot ; 111: 80-5, 2016 May.
Article in English | MEDLINE | ID: mdl-26943902

ABSTRACT

A generalized simulated annealing algorithm, combined with a suitable smoothing regularization function is used to solve the inverse problem of X-ray spectrum reconstruction from attenuation data. The approach is to set the initial acceptance and visitation temperatures and to standardize the terms of objective function to automate the algorithm to accommodate different spectra ranges. Experiments with both numerical and measured attenuation data are presented. Results show that the algorithm reconstructs spectra shapes accurately. It should be noted that in this algorithm, the regularization function was formulated to guarantee a smooth spectrum, thus, the presented technique does not apply to X-ray spectrum where characteristic radiation are present.

8.
Braz J Biol ; 72(2): 287-98, 2012 May.
Article in English | MEDLINE | ID: mdl-22735136

ABSTRACT

The present study investigated the distribution and abundance of epibenthic molluscs and their feeding habits associated to substrate features (coverage and rugosity) in a sandstone reef system in the Northeast of Brazil. Rugosity, low coral cover and high coverage of zoanthids and fleshy alga were the variables that influenced a low richness and high abundance of a few molluscan species in the reef habitat. The most abundant species were generalist carnivores, probably associated to a lesser offer and variability of resources in this type of reef system, when compared to the coral reefs. The results found in this study could reflect a normal characteristic of the molluscan community distribution in sandstone reefs, with low coral cover, or could indicate a degradation state of this habitat if it is compared to coral reefs, once that the significantly high coverage of fleshy alga has been recognized as a negative indicator of reef ecosystems health.


Subject(s)
Coral Reefs , Ecosystem , Feeding Behavior/physiology , Mollusca/physiology , Animals , Brazil , Environmental Monitoring/methods , Mollusca/classification , Population Density , Population Dynamics
9.
Sex Dev ; 6(4): 210-21, 2012.
Article in English | MEDLINE | ID: mdl-22572405

ABSTRACT

In the oyster Crassostrea gigas, a successive hermaphrodite, Cg-Foxl2, an ortholog of Foxl2, is suspected to be involved in vitellogenesis or female sex determination. The existence of a natural antisense transcript (NAT) of this factor has been suspected in gonads but needs to be confirmed to better understand the early events of the gonadic differentiation. The occurrence of this NAT was studied by orientation-specific RT-PCR. The NAT and its mRNA expressions were investigated during the development and in adults by real-time PCR and in situ hybridization. The presence of stable in vivo RNA-RNA duplexes was also explored by RNase protection-based approach. This work is the first evidence of characterization of a NAT in the gonads of mollusks and Lophotrochozoa. This NAT named Cg-Foxl2os is supposed to be polyadenylated and forms RNA-RNA duplexes with its mRNA. Cg-Foxl2os is significantly more expressed than Cg-Foxl2 in 2-month-old spats and in mature males. It is co-localized with the mRNA in the cytoplasm of spermatogonia and spermatocytes. The results of this study demonstrate the existence of a NAT of Cg-Foxl2 in the gonads of C. gigas. It may regulate its mRNA expression through formation of cytoplasmic RNA-RNA duplexes during the oyster gonadic differentiation.


Subject(s)
Crassostrea/embryology , Gonads/cytology , Animals , Cell Differentiation/genetics , Cell Differentiation/physiology , Crassostrea/cytology , Crassostrea/metabolism , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Gonads/metabolism , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Sex Determination Processes/genetics , Sex Determination Processes/physiology
10.
Biol Bull ; 201(2): 167-74, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11687388

ABSTRACT

This study investigates the salinity tolerance and the pattern of osmotic and ionic regulation of Bythograea thermydron Williams, 1980, a brachyuran crab endemic to the deep-sea hydrothermal vent habitat. Salinities of 33 per thousand-35 per thousand were measured in the seawater surrounding the captured specimens. B. thermydron is a marine stenohaline osmoconformer, which tolerates salinities ranging between about 31 per thousand and 42 per thousand. The time of osmotic adaptation after a sudden decrease in external salinity is about 15-24 h, which is relatively short for a brachyuran crab. In the range of tolerable salinities, it exhibits an iso-osmotic regulation, which is not affected by changes in hydrostatic pressure, and an iso-ionic regulation for Na(+) and Cl(-). The hemolymph Ca(2+) concentration is slightly hyper-regulated, K(+) concentration is slightly hyper-hypo-regulated, and Mg(2+) concentration is strongly hypo-regulated. These findings probably reflect a high permeability of the teguments to water and ions. In addition to limited information about salinity around hydrothermal vents, these results lead to the hypothesis that B. thermydron lives in a habitat of stable seawater salinity. The osmoconformity of this species is briefly discussed in relation to its potential phylogeny.


Subject(s)
Brachyura/physiology , Chlorides/physiology , Sodium/physiology , Water-Electrolyte Balance/physiology , Animals , Brachyura/growth & development , Brachyura/metabolism , Chlorides/metabolism , Hemolymph/chemistry , Pacific Ocean , Sodium/metabolism
11.
Phys Rev Lett ; 87(1): 010603, 2001 Jul 02.
Article in English | MEDLINE | ID: mdl-11461455

ABSTRACT

Deterministic walks over a random set of N points in one and two dimensions ( d = 1,2) are considered. Points ("cities") are randomly scattered in R(d) following a uniform distribution. A walker ("tourist"), at each time step, goes to the nearest neighbor city that has not been visited in the past tau steps. Each initial city leads to a different trajectory composed of a transient part and a final p-cycle attractor. Transient times (for d = 1,2) follow an exponential law with a tau-dependent decay time but the density of p cycles can be approximately described by D(p)proportional to p(-alpha(tau)). For tau>>1 and tau/N<<1, the exponent is independent of tau. Some analytical results are given for the d = 1 case.

12.
J Clin Endocrinol Metab ; 85(11): 4168-72, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11095449

ABSTRACT

We have studied the effect of estradiol (E2) on the GH-insulin-like growth factor (GH-IGF) axis in 15 prepubertal GH deficiency (GHD) children and 44 prepubertal or early pubertal children with idiopathic short stature (SS). All of them received a daily dose of micronized E2 (1 or 2 mg) or placebo, for 3 days, before a sequential arginine-clonidine test. In SS children, GH maximal responses were 17.8+/-10.9 on placebo and 27.9+/-14.5 microg/L on estrogen (P < 0.0001). The lower 95% confidence limits for GH maximal response changed from 3.7 microg/L (without E2) to 8.3 microg/L (on E2). In GHD children, no significant stimulatory effect of estrogen on GH levels was observed. After placebo, a cut-off limit of 3.7 microg/L (the lower 95% confidence interval limit) resulted in 73% sensitivity, 95% specificity, and an overall 90% diagnostic efficiency. After E2, a cut-off limit of 8.3 microg/L resulted in a sensitivity of 87%, a specificity of 98%, and a diagnostic efficiency of 95%. After placebo, 68% of SS showed normal IGF-I levels, and the mean did not change on E2 (13.7+/-6.3 vs. 14.3+/-6.8 nmol/L, not significant). In 93% of SS, IGF binding protein (IGFBP)-3 levels were normal during placebo. On E2, mean IGFBP-3 did not change (2.63+/-0.70 vs. 2.70+/-0.70 mg/L, not significant). In 14 of 15 GHD patients, IGF-I values were below normal on placebo, and the mean of the group did not change after E2. During placebo, 13 of 15 GHD children presented low IGFBP-3 values. During E2, there was a small significant increase in IGFBP-3 values (1.06+/-0.58 vs. 1.20+/-0.69 mg/L, P < 0.02). The highest diagnostic efficiencies for IGF-I and IGFBP-3 were observed during placebo (75% and 91%, respectively). We conclude that GH stimulation tests after E2 priming had the highest diagnostic efficiency. Our findings suggest that the effect of estrogen priming on GH stimulated levels, by reducing the number of false nonresponders, might be useful to better discriminate between normal and abnormal GH status in SS children.


Subject(s)
Body Height , Estradiol , Growth Disorders/diagnosis , Human Growth Hormone/blood , Human Growth Hormone/deficiency , Insulin-Like Growth Factor Binding Protein 3/blood , Insulin-Like Growth Factor I/metabolism , Adolescent , Biomarkers/blood , Child , Child, Preschool , Confidence Intervals , Diagnosis, Differential , Female , Growth Disorders/blood , Growth Disorders/physiopathology , Humans , Insulin-Like Growth Factor I/analysis , Male , Placebos , Sensitivity and Specificity
13.
J Acoust Soc Am ; 107(5 Pt 1): 2704-10, 2000 May.
Article in English | MEDLINE | ID: mdl-10830392

ABSTRACT

Adult listeners are able to recognize speech even under conditions of severe spectral degradation. To assess the developmental time course of this robust pattern recognition, speech recognition was measured in two groups of children (5-7 and 10-12 years of age) as a function of the degree of spectral resolution. Results were compared to recognition performance of adults listening to the same materials and conditions. The spectral detail was systematically manipulated using a noise-band vocoder in which filtered noise bands were modulated by the amplitude envelope from the same spectral bands in speech. Performance scores between adults and older children did not differ statistically, whereas scores by younger children were significantly lower; they required more spectral resolution to perform at the same level as adults and older children. Part of the deficit in younger children was due to their inability to utilize fully the sensory information, and part was due to their incomplete linguistic/cognitive development. The fact that young children cannot recognize spectrally degraded speech as well as adults suggests that a long learning period is required for robust acoustic pattern recognition. These findings have implications for the application of auditory sensory devices for young children with early-onset hearing loss.


Subject(s)
Cognition/physiology , Cues , Speech Perception/physiology , Adult , Age Factors , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Noise/adverse effects , Random Allocation
15.
Phys Rev Lett ; 85(26 Pt 1): 5563-6, 2000 Dec 25.
Article in English | MEDLINE | ID: mdl-11136047

ABSTRACT

The energy transport velocity v(E) and the diffusion constant D of electromagnetic waves in the presence of randomly distributed ferromagnetic scatterers are studied. v(E) presents a strong dependence on the relative magnetic permeability mu and, unlike the nonmagnetic case, exhibits sharp drops in the small-particle limit and never coincides with the phase velocity v(p). Both v(E) and D exhibit an oscillatory dependence on mu and vanish for certain values of mu. Since mu of ferromagnetic scatterers strongly depends on the temperature and applied magnetic field, we suggest that these facts can be explored in technological applications.

16.
J Speech Lang Hear Res ; 41(2): 327-39, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9570586

ABSTRACT

The purpose of this investigation was to determine whether subjective judgments of clarity or intelligibility would be rated equally among conditions in which speech was equated for predicted intelligibility (using the Speech Intelligibility Index, SII) but varied in bandwidth. Twenty listeners with normal hearing rated clarity and intelligibility for sentence material (Hearing In Noise Test) in speech-shaped noise at six paired low- and high-pass filtered conditions in which SII was equated for each pair. For three paired conditions, predicted intelligibility increased as SII increased monotonically (0.3, 0.4, 0.5). In the remaining paired conditions, SII continued to increase monotonically (0.6, 0.7, 0.8) but predicted intelligibility was held at a maximal level (> or = 95%). Predicted intelligibility was estimated from the transfer function relating SII to speech recognition scores determined in preliminary experiments. Differences in ratings between paired low- and high-pass filtered sentences did not reach statistical significance for either clarity or intelligibility, indicating that the spectral differences at equivalent SIIs did not influence the judgments for either of the two dimensions. For conditions in which predicted intelligibility increased, both clarity and intelligibility ratings increased in a similar manner. For conditions in which predicted intelligibility was maximized, intelligibility ratings remained the same statistically across conditions while clarity ratings changed modestly. Although high correlations were observed between clarity and intelligibility ratings, intelligibility ratings were consistently higher than clarity ratings for comparable conditions. The results indicated that listeners with normal hearing produced clarity and intelligibility ratings for the same speech material and experimental conditions that were highly related but differed in magnitude. Caution is required when substituting clarity for intelligibility.


Subject(s)
Judgment , Speech Perception , Adolescent , Adult , Analysis of Variance , Female , Humans , Male , Predictive Value of Tests
17.
Acta Paediatr ; 86(11): 1261-2, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9401525

ABSTRACT

To assess the efficacy of treatment with oral desmopressin (DDAVP), 20 patients, aged 5-20 y, with central diabetes insipidus were studied during 3 d of hospitalization and for 3 months at the outpatient clinic. At baseline the median rate of diuresis was 12.7 ml kg-1 h-1. Urinary output decreased significantly under treatment with an increase in urinary osmolality, normalization of plasma osmolality and absence of nocturia. Patients were discharged from hospital with a median dose of 500 micrograms d-1 (100-1200 micrograms d-1). An adjustment in dosage was necessary in seven patients during follow-up, resulting in a final dose of 600 micrograms d-1. Body weight and DDAVP doses (r = 0.75, p = 0.001) and body surface and DDAVP doses (r = 0.72, p < 0.001) were significantly correlated. The average dosage was 474 +/- 222 micrograms m-2 d-1 (mean +/- SD). The oral DDAVP treatment remained effective during the 3 months of follow-up. This therapy offers an alternative for the treatment of central diabetes insipidus in children.


Subject(s)
Deamino Arginine Vasopressin/therapeutic use , Diabetes Insipidus/drug therapy , Hypoglycemic Agents/therapeutic use , Administration, Oral , Adolescent , Adult , Child , Child, Preschool , Diuresis/drug effects , Hospitalization , Humans
18.
Ann Hum Biol ; 22(6): 533-44, 1995.
Article in English | MEDLINE | ID: mdl-8815780

ABSTRACT

Growth data on 254 patients with Turner syndrome from Argentina-120 with XO karyotype and 134 with other chromosomal abnormalities-were analysed. Birth weight and height were significantly reduced. Ninety patients had received oestrogen treatment from a mean age of 14-0 years (SD 1.2) and 17 patients had spontaneous menarche. Patients who underwent spontaneous menarche had a small growth spurt. Final height was slightly higher (139.8 cm SD 5.6), though not significantly different from the mean adult height of the whole sample (137.9 cm SD 5.7). Mean adult height was 3.73 SD below mean of the normal local population. Mean height velocities from birth to maturity are very similar to those found in other samples. Distance standards were prepared by fitting a fifth-degree polynomial to the interpolated mean heights at each 0.5 year of age, and to the raw SD. Selected centiles were then calculated from the smoothed values. Differences between adult height in local Turner syndrome girls and local normal population are very similar to the same Turner-normal differences described in other communities. Standards presented here are useful for evaluating Turner syndrome patients from Argentina, and may also be used by those with similar growth pattern in their normal population.


Subject(s)
Growth , Turner Syndrome/pathology , Adolescent , Adult , Argentina , Body Height/drug effects , Body Height/genetics , Child , Child, Preschool , Chromosome Aberrations , Estrogens/therapeutic use , Female , Growth/drug effects , Growth/genetics , Humans , Infant , Infant, Newborn , Menarche , Turner Syndrome/drug therapy , Turner Syndrome/genetics
19.
Acta Endocrinol (Copenh) ; 129(1): 20-5, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8351954

ABSTRACT

The existence of homologous anti-human growth hormone (anti-hGH) and heterologous anti-bovine growth hormone (anti-bGH) humoral immune responses in hypopituitary patients under hGH therapy has been reported previously. In order to study the influence of the hormone source, both responses were compared by radiobinding assays performed with [125I]hGH or [125I]bGH as tracers. Fifty-seven hypopituitary patients treated with extractive hGH, recombinant methionyl hGH or authentic recombinant hGH were studied. A very low incidence of heterologous antibodies was found in patients under recombinant hGH therapy, contrary to the high incidence observed in patients treated with extractive hGH preparations. In addition, immunochemical studies performed with a synthetic peptide (hGH 44-128) indicated that this peptide exhibited, in the anti-bGH/[125]bGH radioimmunoassay system, higher reactivity than the native hGH, suggesting that such a fragment resembled an altered conformation of the hormone. The high heterologous response elicited only by the extractive hGH along with the behaviour of the hGH 44-128 fragment supports the fact that the extraction and purification procedures in extractive preparations may alter slightly the structure of the hGH molecule and trigger a heterologous immune response.


Subject(s)
Growth Hormone/immunology , Adolescent , Animals , Antibodies/analysis , Antibody Formation , Antibody Specificity , Cattle , Child , Child, Preschool , Female , Growth Hormone/analogs & derivatives , Growth Hormone/therapeutic use , Hormones/therapeutic use , Human Growth Hormone , Humans , Hypopituitarism/drug therapy , Immunochemistry/methods , Infant , Middle Aged , Recombinant Proteins/therapeutic use , Species Specificity
20.
Clin Immunol Immunopathol ; 66(2): 114-9, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8453783

ABSTRACT

Using reliable displacement radiobinding assay (RBA) and ELISA, the existence of anti-human growth hormone autoantibodies (hGHAA) was confirmed in idiopathic hypopituitary patients with growth impairment. Six of 35 hypopituitary patients (17.1%) and 1/85 (1.2%) control children proved positive for hGHAA by RBA (>control mean + 3 SD). IgG isotype-hGHAA by ELISAIgG (> control mean + 3 SD) were positive for 6/34 (17.7%) and 3/85 (3.5% hypopituitary and control children, respectively. Due to an asymmetry to the right of the ELISAIgG distribution, an alternative cutoff based on a nonparametric method was obtained, and positive results for hypopituitary children increased to 10/34 (29.4%). Three of 34 hypopituitary patients but no control children were positive for hGHAA of IgM isotype. The hGHAA were detected in children with or without perinatal problems. These autoantibodies may represent markers of a major autoimmune process involving a portion of the anterior pituitary and may contribute to the development of hypopituitarism in over 15% of hypopituitary children.


Subject(s)
Autoantibodies/blood , Growth Hormone/immunology , Hypopituitarism/immunology , Adolescent , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Radioligand Assay
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