Effects of nutrition restriction of fat- and lean-line broiler breeder hens during the laying period on offspring performance, blood biochemical parameters, and hormone levels.

To evaluate the effects of maternal undernutrition on the performance, blood biochemical indexes, and hormone levels of broiler chicks, two broiler breeder lines (a fat line and lean line) were given either 100% or 75% of the daily feed intake recommended by the Chinese Ministry of Agriculture from 27 to 54 wk. All hens were fed the same basal corn-soybean diet. Fertile eggs were collected and hatched. All chicks were fed the same basal diet for 56 d. Then, chick performance, blood biochemical indexes, and hormone levels were measured. The results showed that there were interactions between maternal nutrition and line for some parameters, such as the kidney index, glucose, triglyceride, insulin, glucagon, leptin, and triiodothyronine (P < 0.05). Chicks of the fat line had a lower level of serum glucose, triglyceride, albumin, glutamic-pyruvic transaminase, insulin, and thyroxin than those of the lean line (P < 0.05), but the opposite trend was seen for birth weight, heart index, leptin, and triiodothyronine (P < 0.05). Maternal undernutrition decreased the birth weight and thymus index (day 28) of offspring (P < 0.05), but these effects disappeared by day 56. Maternal undernutrition decreased glucose (day 28), urea nitrogen (day 56), creatinine (day 56), glutamic-pyruvic transaminase (day 56), creatinine kinase (day 56), and leptin (day 56) levels in the offspring's serum (P < 0.05) but increased creatinine (day 28), total protein (day 28), glutamic-pyruvic transaminase (day 28), and glucagon (day 28) levels (P < 0.05). In conclusion, different lines have different metabolic processes. Maternal nutrition restriction during the laying period did have effects on the offspring, and the compensation by offspring reduced the effect of maternal nutrition restriction.

[Expression of platelet miR-223 in coronary artery disease patients and its clinical significance].

Objective: To investigate the correlation of the expression of platelet microRNA-223 (miR-223) with the degree of platelet activation and the severity of coronary lesions in patients with coronary artery disease (CAD). Methods: A total of 204 consecutive patients underwent coronary artery angiography (CAG) at Beijing Anzhen Hospital between April and December 2016 were enrolled. According to CAG results, all the patients were divided into two groups: 112 patients in CAD group and 92 patients in control group. Real-time fluorescent quantitative PCR was used to detect the expression level of platelet miR-223 and mRNA of its target gene P2Y12. Flow cytometry was performed to detect the expression of platelet associated complement-1 (PAC-1). Results: Compared with control group, the expression level of platelet miR-223 in CAD group was higher [(1.27 (1.17, 1.32) vs 0.73 (0.64, 0.79), P<0.001], while the expression level of P2Y12 mRNA was lower [0.75 (0.51, 0.96) vs 1.00 (0.80, 1.64), P<0.001]. The positive expression rate of PAC-1 of CAD group was higher than that of control group (P<0.001). The expression level of platelet miR-223 was negatively correlated with the expression of P2Y12 (r=-0.39, P=0.02), but positively correlated with the expression of PAC-1 (r=0.50, P<0.001). The platelet miR-223 expression level had a positive correlation with the Gensini score in CAD group (r=0.90, P<0.001), but had no significant correlation with platelet aggregation (r=-0.06, P=0.36). Conclusion: The expression level of platelet miR-223 in patients with CAD may be an indicator for monitoring platelet activation and assessing the severity of CAD.

Thrombomodulin regulates doxorubicin sensitivity through epithelial-mesenchymal transition in non-small cell lung cancer.

OBJECTIVE: Lung cancer has remained the highest about cancer-related mortality and drug resistance is involved in the recurrence of the disease. Thrombomodulin (TM) is down-regulated in several malignant tumors, but its role in drug resistance has not been elucidated in lung cancer. We aimed to investigate the role of TM in drug resistance to lung cancer. MATERIALS AND METHODS: The mRNA and protein expression of TM were determined by real-time PCR and Western blot, respectively. TM expression was manipulated using siRNA or an overexpression system. The expression of epithelial-mesenchymal transition (EMT)-related markers (E-cadherin and vimentin) was detected by real-time PCR and Western blot. RESULTS: We found that A549 and HCC827 cells with higher TM expression were more sensitive to doxorubicin than SPC-A-1 cells with lower TM. Also, downregulation of TM reduced the doxorubicin sensitivity in A549 and HCC827 cells. On the contrary, up-regulated TM increased the doxorubicin cytotoxicity in SPC-A-1 cells. Mechanically, ectopic expression of TM elevated the expression of E-cadherin, an epithelial marker. Conversely, overexpression of TM led to reduced expression of vimentin, a mesenchymal marker, leading to the reversal of EMT in lung cancer cells. As a result, SPC-A-1 cells overexpressing TM become more sensitive to doxorubicin treatment. CONCLUSIONS: These findings showed that TM regulated drug sensitivity through EMT in lung cancer cells, suggesting that TM might be developed into a novel target for lung cancer patients resistant to conventional therapeutics.

Meta-analysis of the IL-10 promoter polymorphisms and pediatric asthma susceptibility.

The results of previous epidemiological studies exploring the relationship between interleukin-10 (IL-10) promoter polymorphisms and susceptibility to pediatric asthma are not consistent. Therefore, we have performed a systematic review and meta-analysis to provide a more convincing conclusion. Odds ratios (OR) with their 95% confidence intervals (CIs) were used to evaluate the strength of association between the IL-10 promoter polymorphisms and susceptibility to pediatric asthma. Publication bias was examined by Begg's funnel plots and the Egger test. A detailed literature search based on stringent parameters yielded sixteen relevant studies, comprising 2494 cases and 2160 controls. The overall population showed no significant association between the IL-10 -1082G/A polymorphism and pediatric asthma risk in any of the genetic models (dominant model: OR = 1.583, 95%CI = 0.614-4.076, P = 0.342; allelic model: OR = 1.214, 95%CI = 0.748-1.971, P = 0.433; additive model: OR = 2.240, 95%CI = 0.950-5.277, P = 0.065; recessive model: OR = 1.435, 95%CI = 0.659-3.128, P = 0.363). Subgroup analyses revealed a significant association between different ethnicity and atopic status subgroups. However, there was no evidence of a significant association between the other two polymorphisms (-819C/ T and -592C/A) and pediatric asthma in our study. No significant publication bias was observed in this meta-analysis. The results of this study indicate that the IL-10 -1082G/A polymorphism might be a risk factor for asthma in children. However, because of the small sample size included in the subgroup analyses, the results should be interpreted with caution.

Effect of temperature on endogenous hormone levels and opposite phyllotaxy in maize leaf primordial.

Newly identified maize (Zea mays) mutants with opposite leaf phyllotaxy are important in the study of the maize crop. Previous studies have revealed the developmental mechanism of opposite phyllotaxy on the physiological, cellular, and molecular levels. However, there have been few reports regarding the effects of changes in endogenous hormone levels in maize leaf primordia under different conditions. We conducted field studies to examine the influence of different environmental factors on leaf primordia differentiation. Our results indicated that compared with other major environmental factors, temperature was significantly positively correlated with the ratio of maize plants with opposite phyllotaxy. We examined endogenous hormone levels in maize at different temperatures using an enzyme-linked immunosorbent assay. The results showed that the ratio of maize plants with opposite phyllotaxy was mainly influenced by the cytokinin/auxin ratio. In addition, at the same temperature, the ratio of cytokinin/auxin in maize with opposite phyllotaxy was significantly higher than that near isogenic lines with alternate phyllotaxy.

Cloning and functional analysis of the promoter of a maize starch synthase III gene (ZmDULL1).

The ZmDULL1 gene encodes a starch synthase and is a determinant of the structure of endosperm starch in maize (Zea mays L.). However, little is known regarding the regulatory mechanism of the ZmDULL1 gene. In this study, we isolated and characterized the ZmDULL1 promoter (PDULL1), which is the 5' flanking region of ZmDULL1 in maize. Sequence analysis showed that several cis-acting elements important for endosperm expression (GCN4_motif and AACA-element) were located within the promoter. A series of PDULL1 deletion derivatives, PDULL1-1-PDULL1-4, from the translation start code (-1676, -1216, -740, and -343) were fused to the ß-glucuronidase (GUS) reporter gene. Each deletion construct was transformed into rice using the Agrobacterium-mediated method, and then GUS activity was measured in transgenic plants. The results showed that PDULL1 was an endosperm-specific promoter. Further analysis showed that the promoter sequence (-343 to -1 base pairs) was sufficient for mediating GUS gene expression in endosperm. These results indicate that the region from -343 to -1 base pairs of PDULL1 is valuable for transgenic rice breeding and genetic engineering studies.

Screening relevant genes of tolerance to low phosphorus in maize using cDNA-amplified fragment length polymorphism.

Soil contains a large amount of phosphorus, but plants cannot absorb most of this phosphorus effectively. Low inorganic phosphorus has been singled out as a major constraint that leads to a perpetually low Zea mays (maize) grain yield. The fundamental approach to solving this problem is to screen new genes of low phosphorous (LP) tolerance. Consequently, the exploration and utilization of LP-tolerant genes are of great significance in plants. The maize inbred line 178 is an inbred LP-tolerant line. In the current study, the expression of this inbred line was induced under the stress of LP conditions. We applied cDNA-amplified fragment length polymorphism to screen LP-tolerant genes and obtained and sequenced 78 differentially expressed gene fragments. Their functions were predicted via bioinformatic analysis. There were no function annotations for 8 differentially expressed fragments. Nine genes exhibited high homology to Arabidopsis thaliana and Oryza sativa genes involved in phosphorus metabolism. This study lays a good foundation for further cloning and verification of the genes involved in phosphorus metabolism in maize.

Association of the IL-4R Q576R polymorphism and asthma in the Chinese Han population: a meta-analysis.

The IL-4R Q576R polymorphism has been reported to increase susceptibility to asthma, but the results are controversial. Thus, we performed a meta-analysis to evaluate the association of the IL-4R Q576R polymorphism and asthma risk in the Chinese Han population. A total of sixteen eligible case-control studies that evaluated the relationship between the IL-4R Q576R polymorphism and asthma in the Chinese Han population were obtained by comprehensive literature search incorporating electronic databases, and included 2077 asthma cases and 1589 controls. Our analysis detected a significant association between the IL-4R Q576R polymorphism and the risk of asthma in the Chinese Han population (Allelic model: OR = 1.481, 95%CI = 1.134-1.935, P = 0.004; Dominant model: OR = 1.542, 95%CI = 1.194-1.990, P = 0.001; Recessive model: OR = 1.695, 95%CI = 1.170-2.456, P = 0.005, Additive model: OR = 1.897, 95%CI = 1.299-2.771, P = 0.005). The year of publication and size of total sample might be sources of between-study heterogeneity. Upon subgroup analysis by size of total sample of each study, the significant association only remained in a subgroup with a small sample size. In summary, our meta-analysis suggested that the IL-4R Q576R polymorphism is associated with asthma in the Chinese Han population.

Overexpression of an endo-1,4-ß-glucanase V gene (EGV) from Trichoderma reesei leads to the accumulation of cellulase activity in transgenic rice.

The ectopic expression of cellulase in biomass can reduce the cost of biofuel conversion. This trait modification technique is highly beneficial for biofuel production. In this study, we isolated an endo-1,4-beta-glucanase gene (EGV) from Trichoderma reesei and inserted this gene downstream of a fragment encoding the signal peptide Apo-SP in a modified pCAMBIA1301 vector to obtain an Apo-SP and AsRed fusion protein. Transient expression of this fusion protein in onion epidermal cells showed that the Apo-SP signal was localized to the plastids. EGV transgenic rice plants that did not carry screening marker genes were obtained through overexpression of the pDTB double T-DNA vector. Western blotting showed that EGV was expressed in the dry straw of T0 generation transgenic rice plants and in fresh leaves of the T1 generation. More importantly, our results also showed that the peptide product of EGV in the transgenic plants folded correctly and was capable of digesting the cellulase substrate CMC. Additionally, cellulase activity remained stable in the straw that had been dried at room temperature for three months. This study presents an important technical approach for the development of transgenic rice straw that has stable cellulase activity and can be used for biofuel conversion.

A genome-wide analysis of the ERF gene family in sorghum.

The ethylene response factor (ERF) family are members of the APETALA2 (AP2)/ERF transcription factor superfamily; they are known to play an important role in plant adaptation to biotic and abiotic stress. ERF genes have been studied in Arabidopsis, rice, grape, and maize; however, there are few reports of ERF genes in sorghum. We identified 105 sorghum ERF (SbERF) genes, which were categorized into 12 groups (A-1 to A-6 and B-1 to B-6) based on their sequence similarity, and this new method of classification for ERF genes was then further characterized. A comprehensive bioinformatic analysis of SbERF genes was performed using a sorghum genomic database, to analyze the phylogeny of SbERF genes, identify other conserved motifs apart from the AP2/ERF domain, map SbERF genes to the 10 sorghum chromosomes, and determine the tissue-specific expression patterns of SbERF genes. Gene clustering indicates that SbERF genes were generated by tandem duplications. Comparison of SbERF genes with maize ERF homologs suggests lateral gene transfer between monocot species. These results can contribute to our understanting of the evolution of the ERF gene family.

RNA interference-mediated silencing of the starch branching enzyme gene improves amylose content in rice.

Amylose and amylopectin are the 2 major components of plant storage starch. The rice starch branching enzyme (RBE) plays an important role in the starch components of rice. In the present study, we selected a specific 195-bp segment from the RBE3 gene to construct hairpin DNA, which was driven by an endosperm-specific high molecular weight glutenin promoter to regulate the biosynthesis of starch. An RNA interference plasmid for the RBE3 gene was constructed to form double-stranded RNA. Following Agrobacterium-mediated rice transformation (in the cultivar Zhonghua 11), 41 transgenic plants were identified using PCR and Southern blot analysis. Semi-quantitative real-time PCR revealed that RBE3 gene expression was significantly reduced in immature transgenic seeds. Transgenic rice amylose content had an average increase of 140%. The highest rice amylose content was 47.61% and the growth rate increased 238% compared to the non-transgenic controls. Branching enzyme II activity was notably reduced, and ADP-glucose pyrophosphorylase, soluble starch synthase, isoamylase, and pullulanase enzyme activity was markedly reduced in T3 seeds. Relative enzyme activity change explained the reduction in thousand-grain weight in transgenic plants. The present study indicated that amylose content was negatively correlated with branching enzyme II activity, spike size, and thousand-grain weight.

Genome-wide analysis of immunophilin FKBP genes and expression patterns in Zea mays.

The receptors for the immunosuppression drugs FK506 and rapamycin are called FKBPs (FK506-binding proteins). FKBPs comprise a large family; they are found in many species, including bacteria, fungi, animals, and plants. As a class of peptidyl-prolyl cis-trans isomerase enzymes, the FKBP genes have been the focus of recent studies on plant stress tolerance and immunology. We identified and analyzed gene families encoding these proteins in maize using computational and molecular biology approaches. Thirty genes were found to encode putative FKBPs according to their FK506-binding domain. The FKBP genes can be classified into single domain and multiple domain members based on the number of the domains. By analysis of the physical locations, the 30 FKBP genes were found to be widely distributed on 10 chromosomes. After analysis of the FKBP phylogenetic tree in the maize genome, we found that the 30 genes revealed two major clades. Gene duplication played a major role in the evolution of FKBP genes, which suggests that the FKBP genes in maize have a pattern significantly different from that of these genes in rice. Based on semi-quantitative RT-PCR, we found that the 30 FKBPs were expressed differently in various tissues in maize, which suggests that FKBP genes play different roles in each tissue. Several FKBPs were expressed at higher levels in roots, indicating that these genes in maize may have similar or overlapping functions.

Molecular mapping of genes for opposite leafing in maize using simple-sequence repeat markers.

Maize with opposite phyllotaxy (OP) and also initiating ears in opposite pairs is an aberrant mutant and also precious material for maize breeding and plant evolution studies. Mapping and identifying the markers closely linked to genes for the OP trait are essential for cloning the gene and marker-assisted selection in breeding. We established H14D, a near-isogenic line of the OP trait with H53 genetic background. We found that the OP trait is regulated by two independent dominant genes with mutually complementary relations, named Opp-1 and Opp-2. Screening of seven simple-sequence repeat (SSR) markers among the 105 pairs of SSR primers showed polymorphism between the inbred lines H14D and H53. The polymorphic SSR markers were then used to determine linkage with the trait in an F(2) population with 441 progeny, suggesting that SSR marker umc2094 in the Bin2.01 region is linked with Opp-1 at 6.7 cM, and bnlg1831 in Bin2.06 is linked with Opp-2 at 6.1 cM. Further investigation showed that bnlg1092 and umc1028 are linked to Opp-1 and Opp-2 genes, with genetic distances of 12.2 and 1.9 cM. It was also found that the four SSR markers flank the two OP genes, respectively. These results will be useful for marker-assisted selection breeding of OP maize and will also strengthen the basis for cloning of the opposite leafing gene.

Genome-wide identification, classification, and analysis of two-component signal system genes in maize.

Cytokinins play many vital roles in plant development and physiology. In plants, cytokinin signals are sensed and transduced by the two-component signal system. This signaling cascade is typically composed of three proteins: a sensory histidine kinase, a histidine phosphotransfer protein, and a response regulator. Through a comprehensive genome-wide analysis of the maize (Zea mays) genome, 48 genes were identified, including 11 ZmHKs, 9 ZmHPs, and 28 ZmRRs (21 A-type ZmRRs and 7 B-type ZmRRs). Using maize genome sequence databases, we analyzed conserved protein motifs and established phylogenetic relationships based on gene structure, homology, and chromosomal location. The duplication of these two-component system genes in the maize genome corresponded to the clusters of these genes in the phylogenetic trees. Sequence analysis of the duplicate genes demonstrated that one gene may be in gene duplication, and that there was significant variation in the evolutionary history of the different gene families. We assessed the expression levels of all ZmRRs in the leaves and roots by reverse transcription PCR; they were all found to be active. Our results provide a foundation for functional and evolutionary studies on maize two-component signal system proteins.

Molecular and functional analysis of the poly-ß-hydroxybutyrate biosynthesis operon of Pseudomonas sp BJ-1.

The operon comprising the genes for poly-ß-hydroxybutyrate (PHB) biosynthesis in Pseudomonas sp BJ-1 was cloned and sequenced. Sequence analysis of 8991 bp revealed that the regions contain two related operons. The first operon contains the three genes phbA, phbB and phbC, and the other contains the two genes flp1 and flp2. The deduced amino acid sequences of PHBA and PHBB showed high identity with other bacterial PHB genes. Transcription of the three genes of the first operon is controlled by a single hypothetical promoter region, whereas the other two flp genes are controlled by two hypothetical promoter regions. Analysis of expressed protein at different times showed that PHBA protein levels increased from 0 to 4 h; PHBB and PHBC showed similar kinetics. Detection of enzyme activity showed three proteins with bioactivity and biological function in the synthesis of PHB intermediates.

Molecular marker-assisted selection of the ae alleles in maize.

The ae (amylose extender) recessive mutant alleles in maize are an important genetic resource for the development of high-amylose cultivars. On the basis of ae allele sequences (from the National Center for Biotechnology Information), the ae mutant alleles were cloned from high-amylose maize and the allelic Ae gene from common maize luyuan92 inbred lines. Five pairs of primers were designed to screen for a molecular marker of ae alleles, yielding a dominant molecular marker, ae474. We used 53 types of high-amylose maize and common maize inbred lines and their hybrid and backcross offspring for verification and analysis. The ae dominant molecular marker was effective in selecting for the ae alleles and for biological materials with a high-amylose genotype. Presence and absence of the marker in the offspring conformed to the expected Mendelian ratios. Using this marker, we were able to detect the ae alleles in a backcross and its second generation more efficiently (53.3 and 73.3%, respectively) than was possible without marker selection. These data indicate that the marker can be used as a tool to improve selection efficiency and accelerate the cultivation of new varieties of high-amylose maize.

Effects of low-energy argon ion implantation on the dynamic organization of the actin cytoskeleton during maize pollen germination.

The relationship between pollen germination and the dynamic organization of the actin cytoskeleton during pollen germination is a central theme in plant reproductive biology research. Maize (Zea mays) pollen grains were implanted with 30 keV argon ion (Ar(+)) beams at doses ranging from 0.78 x 10(15) to 13 x 10(15) ions/cm(2). The effects of low-energy ion implantation on pollen germination viability and the dynamic organization of the actin cytoskeleton during pollen germination were studied using confocal laser scanning microscopy. Maize pollen germination rate increased remarkably with Ar(+) dose, in the range from 3.9 x 10(15) to 6.5 x 10(15) ions/cm(2); the germination rate peaked at an Ar(+) dose of 5.2 x 10(15) ions/cm(2). When the implantation dose exceeded 7.8 x 10(15) ions/cm(2), the rate of pollen germination decreased sharply. The actin filaments assembled in pollen grains implanted with 5.2 x 10(15) ions/cm(2) Ar(+) much earlier than in controls. The actin filaments organized as longer parallel bundles and extended into the emerging pollen tube in treated pollen grains, while they formed random and loose fine bundles and were gathered at the pollen aperture in the control. The reorganization of actin cytoskeleton in the pollen implanted with 9.1 x 10(15) ions/cm(2) Ar(+) was slower than in controls. There was a positive correlation between pollen germination and the dynamic organization of the actin cytoskeleton during pollen germination. Ion implantation into pollen did not cause changes in the polarization of actin filaments and organelle dynamics in the pollen tubes. The effects of Ar(+) implantation on pollen germination could be mediated by changes in the polymerization and rearrangement of actin polymers.

Insulin-like growth factor-binding protein 1 and insulin-like growth factor-binding protein 3 in pre-eclampsia.

OBJECTIVE: To investigate circulating levels of insulin-like growth factor-binding protein 1 (IGFBP-1) and IGFBP-3 in the mother and the fetus in pregnancies complicated by pre-eclampsia, and the relationship between serum levels of IGFBPs and fetal birthweight. DESIGN: A prospective study over an 18 month period. SETTING: A tertiary care academic medical centre. PARTICIPANTS: Sixty-six pregnant women with pre-eclampsia (35 cases of mild/moderate pre-eclampsia and 31 cases of severe pre-eclampsia) and 78 nonpre-eclamptic pregnant women of matched gestational weeks and maternal ages. MAIN OUTCOME MEASURES: Serum concentrations of IGFBP-1 and IGFBP-3 at the time of delivery. RESULTS: In pre-eclampsia associated with intrauterine growth retardation (IUGR), maternal and cord serum IGFBP-1 levels at the time of delivery were elevated. By contrast, circulating IGFBP-3 levels in both the mother and the fetus were lower in pre-eclampsia with IUGR than in nonpre-eclamptic pregnancy. However, there was no difference in serum IGFBP-1 and IGFBP-3 levels between pre-eclampsia without IUGR and nonpre-eclamptic pregnancy in both the mother and the fetus. CONCLUSIONS: In pre-eclampsia, elevated concentrations of circulating IGFBP-1 and decreased serum IGFBP-3 levels were observed in both the mother and the fetus. However, these changes may simply reflect low birthweight in pre-eclampsia.

Insulin-like growth factor-I and insulin-like growth factor-binding protein-1 in Taiwanese women during normal pregnancy.

Circulating levels of insulin-like growth factor-I (IGF-I) and insulin-like growth factor-binding protein-1 (IGFBP-1) in Taiwanese women during normal pregnancy were investigated. Three hundred and eighty-five pregnant women at various gestational ages and 30 nonpregnant females were recruited into the study. Serum concentrations of IGF-I and IGFBP-1 were determined by immunoradiometric assay (IRMA) and radioimmunoassay (RIA). Maternal serum levels of IGF-I increased as pregnancy progressed. Circulating IGF-I levels in women during the first trimester of pregnancy were higher than those in nonpregnant females. Serum levels of IGFBP-1 rose rapidly before 12 weeks of gestation and remained high until term. Serum IGFBP-1 levels in pregnant women during the first trimester were significantly higher than those in nonpregnant females. However, there was no difference in maternal serum IGFBP-1 levels between the second and the third trimester of pregnancy. It is concluded that serum IGF-I levels during pregnancy may be regulated by various classes of IGF-binding proteins other than IGFBP-1.

Serum levels of insulin-like growth factor-binding protein-3 in normal pregnancy.

The aim of this study was to investigate circulating levels of insulin-like growth factor-binding protein-3 (IGFBP-3) in women with normal pregnancy. A total of 468 pregnant women at various gestational ages and 30 non-pregnant females were recruited in this study. Serum concentration of IGFBP-3 was determined by radioimmunoassay. Maternal serum levels of IGFBP-3 increased as pregnancy progressed. The concentration of IGFBP-3 in pregnancy serum was positively associated with the gestational age. The mean values of circulating IGFBP-3 in the second and third trimesters of pregnancy were higher than those in the first trimester of pregnancy and in non-pregnant females. In addition, there was a highly significant correlation between IGFBP-3 and IGF-I in pregnancy serum. We conclude that, during pregnancy, IGFBP-3 appears to be the principal binding protein for circulating IGF-I and may be involved in the regulation of fetal growth.