Evaluation of classic and novel ultrasound signs of placenta accreta spectrum.

OBJECTIVES: Improvement in the antenatal diagnosis of placenta accreta spectrum (PAS) would allow preparation for delivery in a referral center, leading to decreased maternal morbidity and mortality. Our objectives were to assess the performance of classic ultrasound signs and to determine the value of novel ultrasound signs in the detection of PAS. METHODS: This was a retrospective cohort study of women with second-trimester placenta previa who underwent third-trimester transvaginal ultrasound and all women with PAS in seven medical centers. A retrospective image review for signs of PAS was conducted by three maternal-fetal medicine physicians. Classic signs of PAS were defined as placental lacunae, bladder-wall interruption, myometrial thinning and subplacental hypervascularity. Novel signs were defined as small placental lacunae, irregular placenta-myometrium interface (PMI), vascular PMI, non-tapered placental edge and placental bulge towards the bladder. PAS was diagnosed based on difficulty in removing the placenta or pathological examination of the placenta. Multivariate regression analysis was performed and receiver-operating-characteristics (ROC) curves were generated to assess the performance of combined novel signs, combined classic signs and a model combining classic and novel signs. RESULTS: A total of 385 cases with placenta previa were included, of which 55 had PAS (28 had placenta accreta, 11 had placenta increta and 16 had placenta percreta). The areas under the ROC curves for classic markers, novel markers and a model combining classic and novel markers for the detection of PAS were 0.81 (95% CI, 0.75-0.88), 0.84 (95% CI, 0.77-0.90) and 0.88 (95% CI, 0.82-0.94), respectively. A model combining classic and novel signs performed better than did the classic or novel markers individually (P = 0.03). An increasing number of signs was associated with a greater likelihood of PAS. With the presence of 0, 1, 2 and ≥ 3 classic ultrasound signs, PAS was present in 5%, 24%, 57% and 94% of cases, respectively. CONCLUSIONS: We have confirmed the value of classic ultrasound signs of PAS. The use of novel ultrasound signs in combination with classic signs improved the detection of PAS. These findings have clinical implications for the detection of PAS and may help guide the obstetric management of patients diagnosed with these placental disorders. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Human ovarian follicular fluid has functional systems for the generation and modulation of thrombin.

OBJECTIVE: To determine whether prothrombin is present in follicular fluid and whether the enzymatic pathways for prothrombin activation are similar to those in plasma. DESIGN: Follicular fluid samples collected at the time of oocyte harvest for an assisted reproductive technology procedure (ART) were analyzed for a panel of hemostatic proteins with use of a combination of functional, chromogenic, and Western ligand blot analysis. SETTING: An ART clinic and an academic research laboratory. PATIENT(S): Women undergoing ART. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Determination of components of thrombin generation and thrombin modulatory systems using functional and antigenic assay procedures. RESULT(S): Both prothrombin and components of the prothrombinase enzyme complex, which includes factors V, VII, and X, are present in follicular fluid. Other hemostatic proteins, including factors VIII and IX and vonWillebrand factor, are absent. The direct activation of prothrombin to thrombin is similar in follicular fluid and plasma. Like plasma, inhibitors of both thrombin and thrombin generation, including antithrombin, protein C, and alpha2-macroglobulin, are present in follicular fluid. CONCLUSION(S): Only a select group of hemostatic plasma proteins are present in follicular fluid. There is no direct correlation between molecular size and concentration of individual proteins in follicular fluid. These results indicate that the proteins involved in the thrombin-generating and thrombin modulatory pathways may be derived from ovarian cells, suggesting that thrombin may have a role in folliculogenesis.

Small size at birth and later diabetic pregnancy.

OBJECTIVE: To determine whether small size at birth was associated with an increased risk of diabetes in pregnancy. METHODS: Linked birth cohorts were evaluated: that of women born at 37-44 weeks' gestation in 1974, and that of their offspring born 1995-1996, at which time birth certificate data included a checkbox for maternal diabetes. The risk for diabetes was calculated for both a small for gestational age (SGA) group, defined as less than the tenth percentile for gestational age, and an appropriate for gestational age (AGA) group. RESULTS: The relative risk for diabetes in pregnancy among the group that had been small at birth was 3.6 compared with the larger group. This was significant at the P < .001 level. CONCLUSION: A woman's risk of diabetes during pregnancy is increased if she herself was small at birth.

Nucleolar and mitochondrial morphology in bovine embryos reconstructed by nuclear transfer.

The nucleolar and mitochondrial morphology of developing reconstructed bovine nuclear transfer (NT) embryos and stage-matched in vivo-produced control embryos were examined under the electron microscope. Each reconstructed embryo at the one-cell (n = 12), two-cell (n = 5), three-cell (n = 3), four-cell (n = 5), 5-8-cell (n = 5) and blastocyst (n = 3) stages was produced by fusion of a 16-32-cell-stage blatomere with an aged enucleated bovine oocyte. The normal and reconstructed embryos showed similar mitochondrial morphology. However, NT embryos produced several pleiomorphic forms not seen in controls, and were more heterogeneous at early stages of development. Control embryos exhibited nucleolar features considered indicative of rRNA synthesis from the eight-cell stage onwards. In contrast, the NT embryos presented nucleoli with morphology consistent with rRNA synthesis in all embryos examined, except in the three-cell and in two of the five four-cell embryos. From this nucleolar morphology, it was concluded that nuclear reprogramming does not occur immediately following nuclear transfer, but occurs gradually over the first two or three cell cycles.

In vitro development of spontaneously activated bovine oocytes.

PURPOSE: The aim of this study was to compare the development of bovine parthenogenetic and in vitro fertilization-derived (IVF) embryos. Oocytes were matured, fertilized, or allowed to activate spontaneously by aging and then cultured for up to 14 days in vitro. Cleavage and development rates, morphology, ultrastructure, and transcriptional activity were compared. RESULTS: Very few parthenogenotes (7.5% of aged oocytes) were obtained and none developed to the hatched blastocyst stage. The pattern of 3H-uridine incorporation at the two-, four-, and eight-cell stages was similar in both types of embryos. Morphological study, however, revealed that none of the parthenogenotes showed features associated with long-term development: they were developmentally delayed and usually arrested before reaching the blastocyst stage (only 0.5% of aged oocytes developed to the blastocyst stage). Structural differences between parthenogenotes and the IVF-derived embryos were observed at all stages of development. CONCLUSIONS: Structural observation suggested that failure of long-term development of bovine parthenogenotes may have a metabolic basis. Some functional changes appeared to coincide with chronological age rather than developmental age. Even though development of parthenogenotes was limited; some features of nuclear maturation and activation of the embryonic genome occur without contribution of the paternal genome.

Cleavage and 3H-uridine incorporation in bovine embryos of high in vitro developmental potential.

The timing of genome activation in bovine embryos is still not well defined. The objective of this study was therefore to investigate transcription in bovine embryos with a high potential to develop in culture after in vitro fertilization, by examining, autoradiographically, their incorporation of 3H-uridine. Initial experiments determined that developmental potential in vitro could be related to the time of first division of the zygote. Embryos that completed their first cleavage within 30 hours of exposure to sperm were more likely to develop into blastocysts (65.7%) and to hatch (50.9%). Using such embryos, it was found that 10 of 12 8-cell and all 11 4-cell stage embryos were labeled after a 2-4-hr exposure to 3H-Uridine. Among 2-cell stage embryos, 0 of 23, 3 of 17, 8 of 15, and 3 of 4 were labeled after exposure to 3H-uridine of 2, 4, 7, and 10 hr, respectively. Treatment with alpha-amanatin (10-100 micrograms/ml) blocked 3H-uridine incorporation but did not inhibit cleavage during the first 4 cell cycles. It was concluded that transcription occurs as early as the 2-cell stage in bovine embryos in vitro but is not critical to the first four cell cycles.

Light and electron microscopic analysis of bovine embryos derived by in vitro and in vivo fertilization.

PURPOSE: The aim of this study was to examine the morphological features of in vitro fertilization-derived bovine embryos (IVt) and compare them with those of in vivo fertilization-derived (IVv) ones. RESULTS: Light microscopy showed the blastomeres of IVv embryos to have a tendency to be rounder up to the 16-cell stage and to form a more compact mass at the morula stage than in their IVt counterparts. Electron microscopy revealed that as development progressed, some structures (such as microvilli, phagosomes/lysosomes, intercellular junctions and intermediate filaments) appeared or reappeared while others (such as lipid droplets, vesicles with flocculent materials, cortical granules, nuclear annulate lamellae, nuclear envelope blebs) decreased or disappeared. These changes were observed about one cell stage later in IVt than in IVv embryos. Other structures were present in both IVt and IVv embryos, and they morphologically either changed (such as mitochondria, endoplasmic reticulum, Golgi apparatus and nucleoli) or did not change (cytoplasmic annulate lamellae). In contrast to previous reports, vacuolated nucleoli in both IVt and IVv embryos were observed from the two-cell stage. CONCLUSIONS: It was concluded that (1) the development of bovine embryos to the blastocyst stage is like that of other mammalian embryos; (2) IVt and IVv embryos did not show consistent differences in morphological features; (3) although IVt embryos appear delayed in development, this may reflect different definition of age in vivo and in vitro.

Functional analysis of spontaneous movements in preterm infants.

Spontaneous movements of premature infants between 25 and 34 weeks conceptional age were observed for 1 hr on two or three occasions. Subjects had low-risk prognoses and were clinically stable at the time of testing. Behavioral acts were scored using a 0/1 time sampling technique in 60 continuous, 1-min time blocks. Temporal associations between individual movements were found using chi-square analyses. Some associated behaviors contained combinations consistent with neonatal action patterns, for example, single and bilateral leg kicking, head turning, and mouthing. Features of state organization were also evident in that general motor activity (GM), which has been used as a marker of active sleep (AS) in neonates, was found to cluster temporally with startle, facial, and head movements but not eye movements. Behavioral quiescence (> or = 5 s) was dissociated from AS-related behaviors (GM, facial, head, and eye movements). Combinations of state-segregated behaviors were more likely to exhibit co-occurrence within 1-min intervals in infants 30 weeks conceptional age and older.

Spontaneous motility in premature infants: features of behavioral activity and rhythmic organization.

The spontaneous motor activity of clinically stable premature infants, 26-36 weeks gestational age, was investigated. Movements were recorded using a pressure-sensitive transducer positioned below the infant's head and torso. Behavior samples were digitized every 0.5 s during 2 and 3-hr continuous recording sessions. Time-series analyses revealed prominent motility cycles of circa 80 min and circa 30 min. These results are consistent with periodicities in motility and REM activation observed in full-term neonates. The longer rhythms of 70-100 min of motility found in this study establish that these periods are present at this stage of development independent of maternal zeitgebers. Developmental changes in motility rhythms and movement burst durations were also observed. Bout durations became somewhat longer in older (> 30 weeks) infants, but the relative time devoted to movement per session was comparable in older and younger (< or = 30 weeks) infants.

Room-temperature thermodilution cardiac output: proximal injectate lumen vs proximal infusion lumen.

OBJECTIVE: To assess the accuracy of room-temperature thermodilution cardiac output measurements from the venous infusion port. DESIGN: Central venous port cardiac output measurements were compared with venous infusion port measurements in 48 right-heart catheters. INTERVENTION: Three 10-mL injections of 5% dextrose in water were made through each port. The order of port injection was random. RESULTS: The cardiac outputs were 5.8 +/- 1.8 L/min from both ports, with no difference between ports (paired t test). CONCLUSION: Room-temperature thermodilution cardiac output determinations from the venous infusion port can be used in place of central venous port cardiac outputs if the central venous port becomes nonfunctional.

Circadian activity rhythms in SHR and WKY rats: strain differences and effects of clonidine.

The spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) inbred rat strains have been subjected to extensive behavioral and neurochemical characterization. The present study examined free-running circadian activity rhythms in these two strains. Because previous studies indicated that free-running rhythms are altered during chronic clonidine administration, and that SHRs and WKYs may respond differentially to clonidine, the effects of this agent on rhythmicity were compared in the two strains. SHRs were hyperactive and showed shorter free-running periods than did WKYs. Clonidine administration altered free-running rhythms similarly in the two strains, but reduced activity levels only in the relatively hyperactive SHRs. These results are consistent with the hypothesis that central noradrenergic systems influence circadian locomotor activity rhythms.

Optical coatings deposited by reactive ion plating.

The effect of different reactive ion-plating process parameters on the transmittance and the reflectance of single layers of HfO(2), Ta(2)O(5), and SiO(2) are investigated. The optical constants obtained for these three as-deposited materials are presented. Laser-damage threshold trends are examined on single- and double-layer coatings at 1064 nm and on high-reflectance coatings for 248 nm. Single- and double-cavity filters are constructed for the UV (< 1-nm bandwidth) and near-infrared (50-nm bandwidth) regions, respectively. After the filters are postannealed in air at 375 °C for several hours, a shift in the peak wavelengths is observed along with a substantial increase in the peak transmittance. As expected, no significant wavelength shifts result from changes in the humidity of the ambient atmosphere.

A comparison of two autoradiographic methods for detecting radiolabeled nucleic acids in embryos.

Two methods for preparing embryos for autoradiographic study of newly synthesized nucleic acids are described and compared. The first method consists of rapidly fixing radiolabeled embryos with acetic acid:methanol, spreading them on glass slides and exposing them for 8 days with a photographic emulsion. The second method consists of fixing, embedding in resin, and sectioning the embryos before their exposure with the emulsion for 3 weeks. Both techniques have many applications in studies of early embryonic activity, but the spread technique is very sensitive, simpler, and faster.

Development and viability of bovine embryos derived from oocytes matured and fertilized in vitro and co-cultured with bovine oviducal epithelial cells.

A co-culture system using a suspension of detached bovine oviducal epithelial cells (BOEC) has been developed as an effective culture method for supporting the development of bovine embryos derived from oocytes matured and fertilized in vitro. Four commercially available culture media (Waymouth's, Ham's F-10, TCM 199 and Ménézo's B2) supplemented with 10% oestrous cow serum, and a modified Tyrode's medium (TALP) supplemented with 0.6% bovine serum albumin were used. Ménézo's B2 resulted in the highest percentages of total uncleaved presumptive zygotes, and of the cleaved zygotes that reached at least the morula stage (31-46% and 66-74%, respectively). The embryos produced in vitro in B2 with BOEC resembled embryos produced in vivo with regard to numbers of cells (averaging 45.4 in morulae, 101.5 in blastocysts, 174.7 in hatching blastocysts and 195.9 in hatched blastocysts), rate of development (hatching on Day 8-9 of culture in vitro), rate of hatching (66% of cleaved zygotes) and pregnancy rates (63%) resulting from the transcervical transfer of selected embryos.

Chicken transferrin receptor expression during erythroid differentiation and by retrovirus transformed cells.

Antiserum prepared against sucrose gradient purified reticuloendotheliosis virus (REV) recognized the chicken transferrin receptor. Molecules immunoprecipitated from red blood cells (RBC) obtained from embryonic chickens with either the anti-REV reagent or a chicken transferrin immunomatrix were demonstrated to be identical by co-migration in both reducing and nonreducing SDS-polyacrylamide gels and in two-dimensional isoelectric focusing analyses, reciprocal immunodepletion analyses and by peptide mapping. The chicken transferrin receptor was shown to be a 190,000 dalton cell surface membrane molecule consisting of two similar disulfide-bonded subunits of approximately 95,000 daltons. The chicken transferrin receptor was expressed on erythroid cell surface membranes as 95,000 dalton monomers as well as 190,000 dalton dimers. The chicken transferrin receptor was expressed on all differentiation/maturation stages, including mature RBC, of both the primitive and definitive type I erythroid cell series. In adult chickens, the transferrin receptor was expressed by immature erythroid cells in the bone marrow, but not by mature circulating RBC. REV-transformed immature lymphoid cells and avian erythroblastosis virus (AEV)-transformed erythroid cells expressed dimers composed of 95,000 and 110,000 dalton subunits. Comparisons among V8 protease derived peptides from 95,000 dalton transferrin receptors obtained from RBC and REV-transformed lymphoid cells revealed a high degree of homology; however, the 95,000 dalton molecules isolated from REV-transformed lymphoid cells exhibited a 56,000 dalton peptide that was unique. Cloned AEV-transformed erythroleukemia cells induced to differentiate by supplementation of the media with 1 mM butyric acid expressed elevated transferrin receptor levels. Both serological and peptide mapping studies demonstrated the human transferrin receptor on K562 cells and the chicken transferrin receptor to be distinct. However, chicken transferrin was shown to be capable of reacting with the human transferrin receptors on K562 cells.

Human placental steroid sulfatase: purification and properties.

Steroid sulfatase is recovered quantitatively from the 105,000 g h supernatant of human placental microsomes extracted with Triton X-100. The solubilized enzyme has been purified using conventional techniques. Throughout the purification procedure, steroid sulfatase appears to be heterogeneous as evidenced by certain, but not all, criteria. Following polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, the final preparation exhibits a major component and varying amounts of two minor ones. Antibodies raised in rabbits with the heterogeneous immunogen give rise to a single precipitation line when the native enzyme is analyzed by double immunodiffusion or by immunoelectrophoresis. In addition, using aged preparations of microsomes and immunoaffinity techniques, steroid sulfatase activity was found to be associated with the fastest migrating minor component. This finding would suggest that the apparent heterogeneity of purified steroid sulfatase is linked to degradation processes occurring within the microsomal preparations. Steroid sulfatase has a Stokes radius of 56 A, a sedimentation coefficient of 4.85 +/- 0.15S (in Triton-containing buffers) and binds 1.3 g of Triton X-100-per g of protein. The molecular weight of the Triton-protein complex was calculated to be 166,000 in which the glycoprotein portion contribution is about 43% (72,000). In contrast, the apparent molecular weight of the major polypeptide determined on calibrated SDS-gels is 62,000. The purified enzyme exhibits two pH optima with cholesterol sulfate as substrate, an acidic one at pH 5.0 and a second one at pH 7.5. The Km values for cholesterol sulfate, dehydroandrosterone sulfate and p-nitrophenylsulfate were 5.26, 14 and 1,320 microM, respectively.

Localization of cholesteryl sulfate in human spermatozoa in support of a hypothesis for the mechanism of capacitation.

Cholesteryl sulfate is a normal constituent of human spermatozoa. The in vitro uptake of tritiated cholesteryl sulfate resulted in the labeling of all spermatozoa as demonstrated by light-microscope radioautography. The binding of the sterol sulfate was localized mainly in the head and midpiece. Radioautography at the level of the electron microscope revealed that the sterol sulfate is localized on the plasma membrane, mostly in the region of the acrosome. Further proof of this localization was obtained by selective dissolution of the plasma membrane and acrosome of the spermatozoa with low concentrations of Triton X-100. This treatment resulted in the simultaneous removal of tritiated cholesteryl sulfate bound to the spermatozoa. A hypothesis is presented concerning the role of cholesteryl sulfate as a membrane stabilizer and enzyme inhibitor during the maturation of spermatozoa in the epididymis. According to this hypothesis, the cleavage of the sulfate moiety within the female reproductive tract triggers a cascade of events leading to sperm capacitation and fertilization.