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PubMed1988

The Na+/H+ exchanger in immature and mature granulocytic HL-60 cells. Property changes induced by intracellular acidification and cell maturation.

We have compared the properties of the Na+/H+ exchanger in two cell populations: growing promyelocytic HL-60 cells (immature) and HL-60 cells induced to mature into granulocytes by dimethyl sulfoxide. The exchanger was activated by intracellular acidification from pH 7.25 to pH 5.5. In both immature and mature granulocytic cells, this type of activation resulted in the expected increase in Vmax for Na+ uptake but also in an increase in KmNa. Maximum acidification caused an increase in Vmax of approximately 10-fold in both types of cells. The increase in KmNa was influenced by cell maturation. In immature cells, the KmNa was higher than in mature cells at all pH values tested, and this difference increased with acidification. Maximum acidification increased the KmNa from 15 +/- 4 to 124 +/- 17 mM in immature cells and from 10 +/- 3 to 43 +/- 20 mM in mature cells. Intracellular pH also influenced the pattern of inhibition of 22Na uptake by dimethylamiloride, a specific inhibitor of the exchanger. At intracellular pH 7.0 dimethylamiloride inhibition was mostly competitive in immature and competitive in mature cells. At lower intracellular pH, 5.9, the inhibition was mixed in both types of cells. Thus, the properties of the exchanger in granulocytic cells are influenced by the cell maturation stage and the intracellular pH.

Amiloride↗
PubMed1993

Behavior of the components of maturation-promoting factor, cdc2 kinase and cyclin B, during oocyte maturation of goldfish.

We examined the changes that occurred in the two components of maturation-promoting factor (MPF), cdc2 kinase and cyclin B, during oocyte maturation in goldfish, using monoclonal antibodies against the C-terminal sequence of goldfish cdc2 kinase and Escherichia coli-produced full-length goldfish cyclin B. Immature oocytes contained a 35-kDa inactive cdc2 kinase. In addition to the 35-kDa form, a 34-kDa active cdc2 kinase was detected in oocytes undergoing germinal vesicle breakdown (GVBD). Cyclin B was absent in immature oocytes and appeared just before GVBD, coinciding exactly with the appearance of the 34-kDa active cdc2 kinase. Precipitation with p13suc1 beads and anticyclin B antibody revealed that cyclin B formed a complex with cdc2 kinase as soon as it appeared. MPF activation was induced by 1 ng cyclin B after introduction into immature oocytes or oocyte extracts. This corresponds to the amount of cyclin B found in mature oocytes (the concentration in the oocyte is 2 micrograms/ml). These results suggest that MPF activation in fish oocytes is induced by complex formation with preexisting cdc2 kinase and newly synthesized cyclin B during oocyte maturation, a situation differing from that in Xenopus and starfish, in which the cdc2 kinase-cyclin B complex is already present in immature oocytes. Unlike that in Xenopus, an inhibition of protein synthesis in unfertilized mature goldfish oocytes caused a decrease in the cdc2 kinase activity/cyclin B protein level and led to a progression from meiotic metaphase to meiotic anaphase. This result indicates that the mechanisms of maintaining MPF activity in mature goldfish oocytes differ from those in Xenopus.

Amino Acid Sequence↗
PubMed1991

Maturation-promoting factor and p34cdc2 kinase during oocyte maturation of the Japanese quail.

Maturation-promoting factor and a homolog of fission yeast cdc2+ gene product (p34cdc2) were investigated during the final 24 hr of maturation of quail oocytes. Kinase activity of p34cdc2 in the oocyte germinal disk (GD) increased 15 times at maturation. Two bands, at 32 and 34 kDa, were detected in immature oocytes by immunoblotting of SDS-PAGE with anti-p34cdc2 monoclonal antibody. A new band, which is close to the 32-kDa band but with a slightly faster mobility, appeared during maturation. No p34cdc2 could be detected outside the GD. Microinjection of GD extract from mature oocytes caused maturation of Xenopus oocytes.

Animals↗
PubMed2003

The usefulness of the TDx/TDxFLx fetal lung maturity II assay in the initial evaluation of fetal lung maturity.

OBJECTIVE: This study was undertaken to evaluate the usefulness of the TDx/TDxFLx Fetal Lung Maturity II (FLM II) assay (Abbot Laboratories, Abbot Park, Ill) in the initial evaluation of fetal lung maturity. STUDY DESIGN: One hundred twenty-seven women who underwent amniotic fluid collection through amniocentesis or vaginal pool for fetal lung maturity studies were evaluated for inclusion. The uncontaminated amniotic fluid specimens were analyzed within 24 hours with the use of the TDx/TDxFLx FLM II assay with values 55 mg/g or greater considered mature, values between 40 and 54 mg/g considered intermediate, and values 39 mg/g or less considered immature. Eighty-two women with singleton gestations who were delivered within 72 hours were included in the final analysis. We compared the TDX/TDxFLx FLM II test with the presence of neonatal respiratory distress syndrome (RDS). RESULTS: Seven of the 82 (8.5%) neonates had RDS develop. None of the 60 neonates with mature values had RDS develop. Two of 10 (20%) neonates with intermediate values and 5 of 12 (42%) neonates with immature values had RDS develop. With the use of a cutoff value of 55 mg/g, the TDx/TDxFLx FLM II assay had sensitivity and a negative predictive value of 100%, a specificity of 80%, and a positive predictive value of 31.8%. CONCLUSION: The TDx/TDxFLx FLM II assay is a useful tool in determining fetal lung maturity by using a cutoff value of 55 mg/g.

Adult↗
PubMedDate not supplied

[Ultrasound grading of placental maturity and fetal lung maturity].

In 126 pregnant women of the gestational age from the 28th to the 44th gestational week, the biparietal diameter, the abdomen diameter, and the placental maturity after Granum et al. were determined. Amniocentesis was performed for obstetric indication. Also the L/S ratio and the cytological estimation of the gestational age were recorded. The first degree of the placental maturity was found in 37, the second degree in 3, and the third degree in 36 pregnant women. In the first group, BPP was 8.38 +/- 0.75, the abdomen diameter 8.30 +/- 0.63, and pulmonary maturity in 73% of women according to the L/S ratio and in 91.9% according to cytological estimation. In the second group, BPP was 9.15 +/- 0.65, the abdomen diameter 9.03 +/- 0.83, and in 77.9% of women the L/S ratio was higher than 2 but in 56.6% of women, according to cytological estimation, there was a good pulmonary maturity. At the third degree of placental maturity, BPP was 9.49 +/- 0.60, the abdomen diameter 9.63 +/- 0.92, and a good pulmonary maturity in 94.4% of women. The RDS was not observed in 5.6% of newborns with the L/S ratio below 2. According to cytological estimation, BPP below 9.15 was found in pre-term labour and higher than 9.15 in at-term births when in 94% of women the L/S ratio was higher than 2.

Female↗
PubMedDate not supplied

[Fetal lung maturity and skin maturity: 2 distinct concepts and the clinical significance of their differences].

The maturation of the fetal lungs, that is to say the adequate production of surfactant in the fetal alveoli, as it is well known reaches to its end about the 35.-36th week of gestation. Even more closely to the date of delivery, about the 37.-38th week of gestation, the maturation of the fetal skin takes place, so to say the detachment of the Vernix caseosa from the fetal skin into the amniotic fluid. The above mentioned means that the children with "mature skin" should have mature lungs too, so that those children have about nothing to fear from the RDS. That can be proved by the comparison of the values which were measured in 38 cases of the L/S Ratio (as a criterion of the lung-maturity), to those of the turbidity of the amniotic fluid and average quantities of the keratinocytes of the amniotic fluid cell population (as a criterion of the skin-maturity); that observation becomes stronger with the comparison of all those values to a Vernix-Score, which can be completed after delivery.

Amniotic Fluid↗
PubMed1978

Studies on oocyte maturation of the medaka, Oryzias latipes. V. On the structure of steroids that induce maturation in vitro.

The response of oocytes within isolated follicles (800-950 micron in diameter) to various steroids was examined with the teleost fish, Oryzias latipes. Continuous exposure of oocytes, which were removed from ovarian investments 17 hours before predicted germinal vesicle breakdown (GVBD), to C19- or C21-steroids brought about maturation in vitro but never triggered ovulation. The steroids effective in inducing maturation have in common a C=0 (or alpha-OH) group at 3C and a beta-OH group at 17C in the C19-steroids, and a C=O (or beta-OH) group at 3C and a C=O (or alpha-OH) group at 20C in the C21-steroids, in addition to an delta4- or delta5-unsaturated for 5alpha-saturated configuration. The orientation of the hydrogen at 5C seems to be critical in determining the ability of a particular steroid to stimulate oocyte maturation. Maturation of oocytes in the ovaries of hypophysectomized females was induced by administering progesterone, but the mature oocytes did not subsequently undergo ovulation. Thus the steroid hormone is capable of inducing oocyte maturation but apparently does not participate directly in the ovulation of Oryzias latipes oocytes.

Androstanes↗
PubMed2005

Assessment of cortical maturation with prenatal MRI. Part I: Normal cortical maturation.

Cortical maturation, especially gyral formation, follows a temporospatial schedule and is a good marker of fetal maturation. Although ultrasonography is still the imaging method of choice to evaluate fetal anatomy, MRI has an increasingly important role in the detection of brain abnormalities, especially of cortical development. Knowledge of MRI techniques in utero with the advantages and disadvantages of some sequences is necessary, in order to try to optimize the different magnetic resonance sequences to be able to make an early diagnosis. The different steps of cortical maturation known from histology represent the background necessary for the understanding of maturation in order to be then able to evaluate brain maturation through neuroimaging. Illustrations of the normal cortical maturation are given for each step accessible to MRI for both the cerebral hemispheres and the posterior fossa.

Brain↗
PubMed1985

Maturation of chronic lymphocytic leukemia B cells: correlation between the capacity of responding to T-cell factors in vitro and the stage of maturation reached in vivo.

Circulating malignant cells from 15 patients with B-cell chronic lymphocytic leukemia (B-CLL) were examined by the electron microscope (EM) and tested for their capacity to produce immunoglobulin (Ig) molecules using endogenous labeling techniques in vitro. In agreement with previous observations, B-CLL clones from various patients could be subdivided in three distinct groups: immature (type 1) clones, that comprised mainly small resting lymphocytes which synthesized, but degraded Ig of the secretory type intracellularly; mature (type 3) clones consisting mainly of cells with an extended Golgi apparatus and numerous strands of rough endoplasmic reticulum (RER) that secreted Ig molecules; and clones (type 2) at an intermediate maturational stage. When stimulated with T-cell supernatants that contained T-cell replacing factor(s) (TRF), type 3 and, to a lesser extent, type 2 clones differentiated further and secreted increased amounts of Ig. This maturation was not observed when type 1 clones were stimulated with the same supernatants. However, these cells were not incapable of further maturation since they could differentiate in response to phorbol ester (TPA). The present data reinforce the concept that different CLL clones undergo a process of maturation in vivo that may be arrested at different levels and demonstrate that the various clones respond differently to physiological stimuli depending upon the level of maturation already reached in vivo.

B-Lymphocytes↗
PubMed2006

Effects of leptin supplementation in in vitro maturation medium on meiotic maturation of oocytes and preimplantation development of parthenogenetic and cloned embryos in pigs.

The objective of the present study was to investigate the effects of leptin addition in in vitro maturation (IVM) medium on meiotic maturation of oocytes and preimplantation development of parthenogenetic and cloned embryos in pigs. In experiment 1, oocytes were matured in North Carolina State University 23 (NCSU-23) medium supplemented with various concentrations of leptin: 0, 1, 10 and 100 ng/ml. IVM medium added with 10 or 100 ng/ml leptin significantly increased the rate of oocytes reaching metaphase II compared to the control (76.8% and 73.8% versus 61.7%). In experiment 2, the influence of the timing of leptin addition in IVM medium on meiotic maturation of porcine oocytes was assessed, and maximum maturation rate of oocytes developing to metaphase II was achieved when supplemented during the first half (0-22 h), the latter half (22-44 h) or the entire maturation period (0-44 h) compared to the control (80.5%, 84.7% and 78.1% versus 70.4%). In experiment 3, leptin strikingly increased the blastocyst rate of parthenogenetic embryos at the concentration of 10 ng/ml (37.5% versus 21.7%) and this increase was independent of the addition timing (0-44, 0-22, 22-44 h) compared to the control (32.5%, 34.6% and 31.5% versus 16.2%). Moreover, total cell number per blastocyst of parthenogenetic embryos was obviously increased in the 10 and 100 ng/ml leptin treatments as compared with the control (36, 38 versus 28). In experiment 4, 10 ng/ml leptin treatment significantly increased the rate of cleavage (72% versus 56%) of cloned embryos. Meanwhile, the rate of blastocyst formation was also improved although no significant difference was found (12.8% versus 7.1%). Collectively, our results indicate that leptin supplementation in IVM medium may be beneficial not only for developmental potential of oocytes but for subsequent developmental competence of embryos produced by parthenogenetic activation and the cleavage of embryos derived by somatic cell nuclear transfer (SCNT).

Animals↗
PubMed2003

FSH priming improves oocyte maturation, but priming with FSH or hCG has no effect on subsequent embryonic development in an in vitro maturation program.

AIM: To determine whether maturation and subsequent blastocyst development of in vitro matured oocytes can be improved by in vivo follicle stimulating hormone (FSH) or human chorionic gonadotrophin (hCG) priming, using a mouse model. EXPERIMENTAL DESIGN: Five groups of oocytes were used: in vivo control, in vitro matured (IVM) control, IVM after 24 h in vivo priming with FSH, IVM after 48 h in vivo priming with FSH and IVM after 16 h in vivo priming with hCG. In vitro fertilization (IVF) was performed on all groups. Oocyte maturation, fertilization, blastocyst development rates and blastocyst cell numbers were assessed for all groups. RESULTS: Significant improvement in oocyte maturation was observed in the two FSH priming groups compared with the IVM control group (P<0.005 and P<0.001, respectively). There were no significant differences in fertilization between all five groups. Blastocyst development was significantly higher in the in vivo control compared to the IVM groups (P<0.001). No significant differences were observed in blastocyst cell numbers among all five groups. CONCLUSIONS: While FSH priming improves the maturation rate of IVM oocytes, FSH or hCG priming does not improve development to the blastocyst stage.

Animals↗
PubMed2002

Immature, semi-mature and fully mature dendritic cells: which signals induce tolerance or immunity?

Dendritic cells (DCs) are currently divided into tolerogenic immature and immunogenic mature differentiation stages. However, recent findings challenge this model by reporting mature DCs as inducers of regulatory CD4+ T cells in vivo. This implies that decisive tolerogenic and immunogenic maturation signals for DCs might exist. Closer inspection reveals that tolerance is observed when partial- or semi-maturation of DCs occurs, whereas only full DC maturation is immunogenic. The decisive immunogenic signal seems to be the release of proinflammatory cytokines from the DCs. Moreover, the semi-mature DC phenotype is comparable to steady-state migratory veiled DCs within the lymphatics, which seem to continuously tolerize lymph node T cells against tissue-derived self-antigens or apoptotic cells.

Animals↗
PubMed2005

Crystallographic structures of Discosoma red fluorescent protein with immature and mature chromophores: linking peptide bond trans-cis isomerization and acylimine formation in chromophore maturation.

The mature self-synthesizing p-hydroxybenzylideneimidazolinone-like fluorophores of Discosoma red fluorescent protein (DsRed) and Aequorea victoria green fluorescent protein (GFP) are extensively studied as powerful biological markers. Yet, the spontaneous formation of these fluorophores by cyclization, oxidation, and dehydration reactions of tripeptides within their protein environment remains incompletely understood. The mature DsRed fluorophore (Gln 66, Tyr 67, and Gly 68) differs from the GFP fluorophore by an acylimine that results in Gln 66 Calpha planar geometry and by a Phe 65-Gln 66 cis peptide bond. DsRed green-to-red maturation includes a green-fluorescing immature chromophore and requires a chromophore peptide bond trans-cis isomerization that is slow and incomplete. To clarify the unique structural chemistry for the individual immature "green" and mature "red" chromophores of DsRed, we report here the determination and analysis of crystal structures for the wild-type protein (1.4 A resolution), the entirely green DsRed K70M mutant protein (1.9 A resolution), and the DsRed designed mutant Q66M (1.9 A resolution), which shows increased red chromophore relative to the wild-type DsRed. Whereas the mature, red-fluorescing chromophore has the expected cis peptide bond and a sp(2)-hybridized Gln 66 Calpha with planar geometry, the crystal structure of the immature green-fluorescing chromophore of DsRed, presented here for the first time, reveals a trans peptide bond and a sp(3)-hybridized Gln 66 Calpha with tetrahedral geometry. These results characterize a GFP-like immature green DsRed chromophore structure, reveal distinct mature and immature chromophore environments, and furthermore provide evidence for the coupling of acylimine formation with trans-cis isomerization.

Acylation↗
PubMed1991

[Placental maturity at term and functional placental performance: CTG changes in relation to histologic detection of placental maturation reserves].

Cardiotocography (CTG) is to be considered today's most sensitive monitoring tool for the functional surveillance of placental performance during parturition. 351 cardiotocographically monitored singleton pregnancies were used as patient material for fine tissue examination of the state of maturity of the villi of the relevant placentas. In histological assessment, placental diagnoses are allocated to defined CTG changes; in particular, however, the identification of reserves, capable of maturing (immature intermediate villi in the centres of the placental subdivisions or placentones), is subject to separate scrutiny. The following results emerge clearly: terminal placentas without maturing potentials, prematurely matured placentas and placentas with deficiency of terminal villi, as well as the absence of immature intermediate villi in the centers of the placentones, are connected with a suspected prepathological or pathological CTG assessment. The histological groups have the lowest incidence of the normal oscillatory type and normal oscillatory frequency and have the highest proportion of abnormal CTG assessments according to the Hammacher score. The absence of the identification of potential maturing reserves (immature intermediate villi) is associated with the highest incidence of Caesarean sections (29.8%). These results show, that the physiological maturing potentials (immature intermediate villi) which can be identified up to term are a histological indication towards regular placental performance, even in labour.

Cardiotocography↗
PubMed2005

Effect of hexoses and gonadotrophin supplementation on bovine oocyte nuclear maturation during in vitro maturation in a synthetic follicle fluid medium.

In vitro oocyte maturation (IVM) culture conditions have been relatively unchanged over the past few decades and remain suboptimal. In contrast, studies of the in vivo environment have led to significant improvements to in vitro embryo culture technologies. The aim of the present study was to determine the effect of maturing bovine cumulus-oocyte complexes (COCs) in medium based on the composition of bovine follicular fluid (Bovine VitroMat; Cook Australia, Eight Mile Plain, Qld, Australia). In particular, the effect of different glucose concentrations and glucosamine supplementation on meiotic maturation was determined. Culturing COCs in the presence of gonadotrophins in Bovine VitroMat, containing either physiological glucose concentrations (2.3 mM) or 5.6 mM (equivalent to levels in Tissue Culture Medium 199 (TCM199)) supplemented with glucosamine resulted in comparable cumulus expansion to COCs cultured in TCM199 plus gonadotrophins. However, nuclear maturation was 1.3-fold lower in Bovine VitroMat cultures containing 2.3 mM glucose compared with 5.6 mM glucose and this effect was independent of glucosamine supplementation. Investigations into the effects of different glucose concentrations and gonadotrophin supplementation during the initial 6 h of maturation demonstrated that COCs cultured in Bovine VitroMat with 5.6 mM glucose without gonadotrophins had a twofold acceleration of the rate of meiotic resumption, yet the rate of polar body formation was decreased by approximately 20% compared with cultures in 2.3 mM glucose and TCM199. However, this effect was not seen when COCs were cultured for the initial 16 h in Bovine VitroMat + 5.6 mM minus gonadotrophins or in Bovine VitroMat + 2.3 mM glucose +/- gonadotrophins. These data demonstrate that glucose concentrations and the timing of the introduction of gonadotrophin during IVM have variable effects on nuclear maturation. Manipulation of glucose concentrations may be a mechanism to influence oocyte meiotic progression and may lead to the development of improved IVM systems, allowing for an increased developmental capacity of bovine oocytes.

Animals↗
PubMed1976

Induction of maturation (meiosis) in small Xenopus laevis oocytes by injection of maturation promoting factor.

Treatment of small-(stage III) or medium-sized (stage IV) Xenopus laevis oocytes with progesterone, human chorionic gonadotropin, or para-hydroxymercuriphenylsulfonate does not induce maturation. Only the full-grown oocytes (stage VI) undergo maturation when treated with either one of these three substances. In contrast, injection of maturation promoting factor into oocytes of stages III-VI invariably leads to chromosome condensation and germinal vesicle breakdown. No maturation spindle is found in oocytes smaller than 0.9 nm in diameter, and the nuclear sap does not mix with the cytoplasm in the smallest (0.45-0.55 mm in diameter) oocytes. In oocytes of 0.9 mm, maturation is identical to that of full-grown oocytes, except that the maturation spindle does not reach the cortex of the oocyte. Progesterone increases protein synthesis in medium-sized (0.8 mm in diameter) oocytes without inducing meiosis. It has little or no effect on protein synthesis in smaller oocytes.

Animals↗
PubMed2006

Molecular analysis of maturation processes by protein and phosphoprotein profiling during in vitro maturation of bovine oocytes: a proteomic approach.

Cellular maturation and differentiation processes are accompanied by the expression of specific proteins. Especially in oocytes, there is no reliable strict linear correlation between mRNA levels and the abundance of proteins. Furthermore, the activity of proteins is modulated by specific kinases and phosphatases which control cellular processes like cellular growth, differentiation, cell cycle and meiosis. During the meiotic maturation of oocytes, the activation of protein kinases, namely of the MPF and MAPK play a predominant role. Therefore, the present study was performed to analyze meiotic maturation at a molecular level, concerning alterations of the proteom and phosphoproteom during IVM. Using a proteomic approach by combining two-dimensional gel electrophoresis followed by selective protein and phosphoprotein staining and mass spectrometry, we identified proteins which were differentially expressed and/or phosphorylated during IVM. Furthermore, we used the MPF inhibitor butyrolactone I, to reveal new molecular effects which are potentially essential for successful maturation. The results show that approximately 550 protein spots could be visualized by the fluorescent dye Sypro ruby at any maturation stage (GV, M I, M II) investigated. From GV stage to M II, ProQ diamond staining indicate in GV 30%, in M I 50%, and in M II 45% of the spots were phosphorylated. The Identity of 40 spots could be established. These proteins belong to different families, for example, cytoskeleton, molecular chaperons, redox, energy and metabolism related proteins, nucleic acid binding proteins, cell cycle regulators, and protein kinases. Four of them were differentially expressed (alteration higher than factor 2) during IVM, namely tubulin beta-chain, cyclin E(2), protein disulfide isomerase and one of two different forms of peroxiredoxin 2. Seven proteins were differentially stained by ProQ diamond, indicating a differential phosphorylation. These are tubulin beta-chain, beta-actin, cyclin E(2), aldose reductase and UMP-synthase, protein disulfide isomerase 2, and peroxiredoxin 2. Furthermore, the results indicate that the phosphorylation of at least peroxiredoxin 2 respond to BL I treatment. This indicates that its phosphorylation is under the control of MPF or MAPK. In summary these results indicates that the reduction of cyclin Eexpression and the (partially) inactivation of peroxiredoxin 2 by phosphorylation, hence alterations in the peroxide levels which can mediate signal transduction are essential components for successful maturation.

4-Butyrolactone↗
PubMed1984

Auer rods in mature granulocytes: a unique morphologic feature of acute myelogenous leukemia with maturation.

The authors observed Auer rods in mature neutrophils, bands, and metamyelocytes in two children with AML with maturation (FAB M2). In order to determine if this rare finding was characteristic of AML M2, the authors reviewed the bone marrows and peripheral blood smears of 50 children with AML M2 and 50 children with other AML subtypes (FAB M1, M3, M4, and M5). They found Auer rods in mature neutrophils and band forms in 10 of 50 patients (20%) with AML M2 but in none of 50 patients with non-M2 AML. This finding was not related to the frequency of mature cells in the specimen or to the frequency of Auer rods in blasts. Cytogenetics did not show a consistent abnormality. The presence of Auer rods in mature granulocytes is unique to FAB M2 AML in the authors' series and supports the concept that in AML at least some of the mature myeloid cells are involved in the leukemic process.

Adolescent↗