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Antenatal infection/inflammation and postnatal lung maturation and injury
Alan H Jobe, Machiko Ikegami
Respiratory Research , 2001, DOI: 10.1186/rr35
Abstract: Recent information supports the concept that infection/inflammation resulting in preterm delivery can promote both early lung maturation and lung injury. As Fig. 1 illustrates, the lung continues to develop after preterm birth. The human lung undergoes a transition from the canalicular stage to the saccular stage of development at about 22 weeks, and alveolarization by secondary septal formation does not begin until about 30–32 weeks gestation [1]. Therefore, both clinical events in fetal life before preterm birth at 26 weeks gestation (65% of gestation) and preterm birth itself have the potential to adversely or beneficially influence lung function and the outcome of the infant. One of the themes of this review is that pro-inflammation is common to many of the events that occur with preterm birth, neonatal adaptation to air breathing, and subsequent lung function. The details of the modulation of lung injury and maturation by pro-inflammation have not yet been identified, and much of what follows is hypothetical and occasionally speculative. However, the epidemiologic information, some of the clinical associations, and the initial investigative work with model systems support the need for further research in this area.Preterm fetuses infected with virulent organisms such as Escherichia coli, Group B Streptococcus or Listeria monocytogenes have sepsis/pneumonia syndromes. However, such presentations are rare before 30 weeks gestation. In contrast 50% or more of fetuses delivered before 30 weeks gestation have chronic chorioamnionitis, as indicated by histologic examination of the fetal membranes and cord, cell counts in the amniotic fluid, or culture positivity for vaginal and commensal organisms that are not generally considered pathologic [2]. More surprisingly, many of these fetuses may have been exposed to low-grade inflammation for prolonged periods, possibly beginning with colonization of the uterine tissue prior to conception. For reasons that are presently u
In Vitro Oocyte Maturation in Polycystic Ovarian Syndrome Patients  [PDF]
Fatemeh Ramazanzadeh,Mansur Malek Aksa,Said Amanpour,Maryam Bagheri
International Journal of Fertility & Sterility , 2007,
Abstract: Prevalence of Polycystic Ovarian Syndrome(PCOS) in Iran is more than 6%. Therefore we encounter with many PCOS patients. In Vitro Maturation (IVM) of oocytes as an attractive method in ART is considered. Studies show that changes in culture conditions should be administered to make IVM protocol more successful .For this purpose in this study we have set up the beneficial cultures for IVM procedure. Fourteen PCOS patients received FSH, 75 IU or 150 IU per day for 3 days initiating on day 3 of menstruation. Oocyte retrieval was performed transvaginally using an ultrasound-guided 17-gauge single lumen needle and filtered through a 70 micron gauge filter. Viable oocytes were put to maturation in TCM-199 supplemented with 10% Patient serum, recombinant FSH, pyruvate, penicillin, streptomycin sulphate and human chorionic gonadotropin..Oocytes were then inseminated by ICSI. The results indicated that 43.4% of oocytes matured to metaphase II. After 48 hours 47.5 % of M II oocytes fertilized by ICSI and cleaved to 2- and 4-cell stage. No pregnancy observed in PCOS patients. The oocytes maturation rate (43.4%) and embryo formation (47.5 %) from immature oocytes obtained in our IVM and ICSI culture system indicate that the present system may be nearly good, even though the number of patients were too small to draw significant conclusions.
Differential gene expression associated with postnatal equine articular cartilage maturation
Michael J Mienaltowski, Liping Huang, Arnold J Stromberg, James N MacLeod
BMC Musculoskeletal Disorders , 2008, DOI: 10.1186/1471-2474-9-149
Abstract: Total RNA was isolated from the articular cartilage of neonatal (0–10 days) and adult (4–5 years) horses, subjected to one round of linear RNA amplification, and then applied to a 9,367-element equine-specific cDNA microarray. Comparisons were made with a dye-swap experimental design. Microarray results for selected genes (COL2A1, COMP, P4HA1, TGFB1, TGFBR3, TNC) were validated by quantitative polymerase chain reaction (qPCR).Fifty-six probe sets, which represent 45 gene products, were up-regulated (p < 0.01) in chondrocytes of neonatal articular cartilage relative to chondrocytes of adult articular cartilage. Conversely, 586 probe sets, which represent 499 gene products, were up-regulated (p < 0.01) in chondrocytes of adult articular cartilage relative to chondrocytes of neonatal articular cartilage. Collagens, matrix-modifying enzymes, and provisional matrix non-collagenous proteins were expressed at higher levels in the articular cartilage of newborn foals. Those genes with increased mRNA abundance in adult chondrocytes included leucine-rich small proteoglycans, matrix assembly, and cartilage maintenance proteins.Differential expression of genes encoding matrix proteins and matrix-modifying enzymes between neonates and adults reflect a cellular maturation process in articular chondrocytes. Up-regulated transcripts in neonatal cartilage are consistent with growth and expansion of the articular surface. Expression patterns in mature articular cartilage indicate a transition from growth to homeostasis, and tissue function related to withstanding shear and weight-bearing stresses.At birth, articular cartilage is relatively homogeneous. That is, the cellular and molecular structures do not vary from site to site topologically across the joint [1-6]. During postnatal maturation in mammals, articular cartilage undergoes architectural reorganization associated with growth and changes in biomechanical demands on the tissue [1-3,5]. For equine articular chondrocytes, the p
TSG-6 protein and its role during maturation of ovarian follicles  [PDF]
Piotr Trzeciak,?ukasz R?pa?a,Rafa? Starzyński,Sebastian D?browski
Post?py Higieny i Medycyny Do?wiadczalnej , 2012,
Abstract: TSG-6 is an ~35 kDa glycoprotein belonging to the hyaluronan binding family. Its expression is induced as a result of an inflammatory condition and during ovulation. TSG-6 is a crucial protein engaged in extracellular matrix synthesis and organization of cumulus-oophorus-complexes (COCs) in preovulatory ovarian follicles. TSG-6 catalyzes cross-linking via heavy chains of trypsin α inhibitor and hyaluronan. This reaction is essential for proper cumulus cell expansion. This process is correlated with purchasing competence by the oocyte. Disorders of the synthesis of TSG-6 cause irregularities in expansion of cumulus cells during ovarian follicle maturation. Therefore, TSG-6 is a potential molecular marker of oocyte maturation.
Gene Expression Profiling of the Cephalothorax and Eyestalk in Penaeus Monodon during Ovarian Maturation
Philip Brady, Abigail Elizur, Richard Williams, Scott F. Cummins, Wayne Knibb
International Journal of Biological Sciences , 2012,
Abstract: In crustaceans, a range of physiological processes involved in ovarian maturation occurs in organs of the cephalothorax including the hepatopancrease, mandibular and Y-organ. Additionally, reproduction is regulated by neuropeptide hormones and other proteins released from secretory sites within the eyestalk. Reproductive dysfunction in captive-reared prawns, Penaeus monodon, is believed to be due to deficiencies in these factors. In this study, we investigated the expression of gene transcripts in the cephalothorax and eyestalk from wild-caught and captive-reared animals throughout ovarian maturation using custom oligonucleotide microarray screening. We have isolated numerous transcripts that appear to be differentially expressed throughout ovarian maturation and between wild-caught and captive-reared animals. In the cephalothorax, differentially expressed genes included the 1,3-β-D-glucan-binding high-density lipoprotein, 2/3-oxoacyl-CoA thiolase and vitellogenin. In the eyestalk, these include gene transcripts that encode a protein that modulates G-protein coupled receptor activity and another that encodes an architectural transcription factor. Each may regulate the expression of reproductive neuropeptides, such as the crustacean hyperglycaemic hormone and molt-inhibiting hormone. We could not identify differentially expressed transcripts encoding known reproductive neuropeptides in the eyestalk of either wild-caught or captive-reared prawns at any ovarian maturation stage, however, this result may be attributed to low relative expression levels of these transcripts. In summary, this study provides a foundation for the study of target genes involved in regulating penaeid reproduction.
Insights into Eyestalk Ablation Mechanism to Induce Ovarian Maturation in the Black Tiger Shrimp  [PDF]
Umaporn Uawisetwathana, Rungnapa Leelatanawit, Amornpan Klanchui, Juthatip Prommoon, Sirawut Klinbunga, Nitsara Karoonuthaisiri
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024427
Abstract: Eyestalk ablation is commonly practiced in crustacean to induce ovarian maturation in captivity. The molecular mechanism of the ablation has not been well understood, preventing a search for alternative measures to induce ovarian maturation in aquaculture. This is the first study to employ cDNA microarray to examine effects of eyestalk ablation at the transcriptomic level and pathway mapping analysis to identify potentially affected biological pathways in the black tiger shrimp (Penaeus monodon). Microarray analysis comparing between gene expression levels of ovaries from eyestalk-intact and eyestalk-ablated brooders revealed 682 differentially expressed transcripts. Based on Hierarchical clustering of gene expression patterns, Gene Ontology annotation, and relevant functions of these differentially expressed genes, several gene groups were further examined by pathway mapping analysis. Reverse-transcriptase quantitative PCR analysis for some representative transcripts confirmed microarray data. Known reproductive genes involved in vitellogenesis were dramatically increased during the ablation. Besides these transcripts expected to be induced by the ablation, transcripts whose functions involved in electron transfer mechanism, immune responses and calcium signal transduction were significantly altered following the ablation. Pathway mapping analysis revealed that the activation of gonadotropin-releasing hormone signaling, calcium signaling, and progesterone-mediated oocyte maturation pathways were putatively crucial to ovarian maturation induced by the ablation. These findings shed light on several possible molecular mechanisms of the eyestalk ablation effect and allow more focused investigation for an ultimate goal of finding alternative methods to replace the undesirable practice of the eyestalk ablation in the future.
Ultrastructural changes in female hepatocytes during ovarian maturation of Steindachnerina insculpta (Pisces: Curimatidae)
Ribeiro, V. M. A.;Bazzoli, N.;Maria, T. A.;Santos, G. B.;
Brazilian Journal of Biology , 2006, DOI: 10.1590/S1519-69842006000600002
Abstract: during gonadal maturation the females of steindachnerina insculpta, a teleost of the furnas reservoir, minas gerais, brazil, show low hepatosomatic and high gonadossomatic indexes, suggesting possible transference of hepatic substances to the ovaries. in comparison to the resting phase, in the maturation/mature one the hepatocytes show greater development of both smooth and rough endoplasmic reticula, increased electron density in the mitochondria, and glycogen scattered throughout the cytoplasm. in both resting and maturation/mature phases, the hepatic parenchyma contains melanomacrophagic centers that consist of degenerating cellular debris and are surrounded by capsules formed by cells, resembling fibroblasts, joined by desmosomes. no physiological relation of these centers with ovarian maturation was found.
Postnatal maturation of somatostatin-expressing inhibitory cells in the somatosensory cortex of GIN mice  [PDF]
Amanda K. Kinnischtzke,Jon M. Berkepile,Erika E. Fanselow
Frontiers in Neural Circuits , 2012, DOI: 10.3389/fncir.2012.00033
Abstract: Postnatal inhibitory neuron development affects mammalian brain function, and failure of this maturation process may underlie pathological conditions such as epilepsy, schizophrenia, and depression. Furthermore, understanding how physiological properties of inhibitory neurons change throughout development is critical to understanding the role(s) these cells play in cortical processing. One subset of inhibitory neurons that may be affected during postnatal development is somatostatin-expressing (SOM) cells. A subset of these cells is labeled with green-fluorescent protein (GFP) in a line of mice known as the GFP-positive inhibitory neurons (GIN) line. Here, we studied how intrinsic electrophysiological properties of these cells changed in the somatosensory cortex of GIN mice between postnatal ages P11 and P32+. GIN cells were targeted for whole-cell current-clamp recordings and ranges of positive and negative current steps were presented to each cell. The results showed that as the neocortical circuitry matured during this critical time period multiple intrinsic and firing properties of GIN inhibitory neurons, as well as those of excitatory (regular-spiking [RS]) cells, were altered. Furthermore, these changes were such that the output of GIN cells, but not RS cells, increased over this developmental period. We quantified changes in excitability by examining the input–output relationship of both GIN and RS cells. We found that the firing frequency of GIN cells increased with age, while the rheobase current remained constant across development. This created a multiplicative increase in the input–output relationship of the GIN cells, leading to increases in gain with age. The input–output relationship of the RS cells, on the other hand, showed primarily a subtractive shift with age, but no substantial change in gain. These results suggest that as the neocortex matures, inhibition coming from GIN cells may become more influential in the circuit and play a greater role in the modulation of neocortical activity.
Hypothalamic Neuroendocrine Circuitry is Programmed by Maternal Obesity: Interaction with Postnatal Nutritional Environment  [PDF]
Hui Chen, David Simar, Margaret J. Morris
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0006259
Abstract: Objective Early life nutrition is critical for the development of hypothalamic neurons involved in energy homeostasis. We previously showed that intrauterine and early postnatal overnutrition programmed hypothalamic neurons expressing the appetite stimulator neuropeptide Y (NPY) and suppressor proopiomelanocortin (POMC) in offspring at weaning. However, the long-term effects of such programming and its interactions with post-weaning high-fat-diet (HFD) consumption are unclear. Research Design and Methods Female Sprague Dawley rats were exposed to chow or HFD for 5 weeks before mating, throughout gestation and lactation. On postnatal day 1, litters were adjusted to 3/litter to induce postnatal overnutrition (vs. 12 in control). At postnatal day 20, half of the rats from each maternal group were weaned onto chow or HFD for 15 weeks. Hypothalamic appetite regulators, and fuel (glucose and lipid) metabolic markers were measured. Results Offspring from obese dams gained more weight than those from lean dams independent of post-weaning diet. Maternal obesity interacted with post-weaning HFD consumption to cause greater levels of hyperphagia, adiposity, hyperlipidemia, and glucose intolerance in offspring. This was linked to increased hypothalamic NPY signaling and leptin resistance in adult offspring. Litter size reduction had a detrimental impact on insulin and adiponectin, while hypothalamic NPY and POMC mRNA expression were suppressed in the face of normal energy intake and weight gain. Conclusions Maternal obesity, postnatal litter size reduction and post-weaning HFD consumption caused obesity via different neuroendocrine mechanims. There were strong additive effects of maternal obesity and post-weaning HFD consumption to increase the metabolic disorders in offspring.
Identification of the stages of ovarian maturation of the Argentine hake Merluccius hubbsi Marini, 1933 (Teleostei: Merlucciidae): advantages and disadvantages of the use of the macroscopic and microscopic scales
Honj, Renato M.;Vaz-dos-Santos, André M.;Rossi-Wongtschowsk, Carmen Lúcia D. B.;
Neotropical Ichthyology , 2006, DOI: 10.1590/S1679-62252006000300004
Abstract: the argentine hake merluccius hubbsi is a demersal-pelagic species on which few studies have been undertaken, despite its importance for the fisheries of the south-southeastern brazilian region, . the species is the most important commercial fishery resource in uruguay and argentina, where several studies have permitted the proper monitoring of the species. the ovarian maturation of the argentine hake is analysed in this study. a scale of maturation is presented in the light of the oocyte development and the use of macro and microscopic scales of ovarian maturation are compared. it was detected that the oocyte types and derived structures present in the ovaries are similar to those already described both for the species and for teleosts in general; group synchronous development and multiple spawning are typical. the identification of ovarian maturation based only on external morphological characteristics of the gonads presents many errors, mainly in the characterization of the stages of maturation, which makes imperative the parallel analysis of the oocyte development, undertaken through histological ovarian cross-sections.
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