Main conclusion
During antipodal cells PCD, polytene chromosomes rearrangement, segregation of nucleoli components and extrusion of nuclear components occur, cytochrome c is released from the ...mitochondria and DNA breaks appear.
We studied in detail the nuclei of cells of the antipodal complex of wheat embryo sac (
Triticum aestivum
L.) during programmed cell death (PCD). The antipodal complex has been reported to be formed before double fertilisation of the embryo sac. Polyploidisation leads to the formation of giant polytene chromosomes in the nuclei of antipodal cells. These chromosomes are involved in secretory functions and are important for the development of cellular endosperm. Terminal deoxynucleotidyl transferase dUTP nick end labelling assay and immunodetection revealed DNA breaks in the nuclei and release of cytochrome c from mitochondria into the cytoplasm of antipodal cells during PCD. We used transmission electron microscopy, immunodetection and histochemistry to analyse the characteristic structural changes in the nuclei of antipodal cells during PCD. These included sequential structural changes in the nuclei containing polytene chromosomes, segregation of some components of the nucleolus into the bodies of polytene chromosomes, extrusion of nucleolar components and parts of chromosomes into the cytoplasm of antipodal cells and then into the endosperm coenocyte. The obtained results expand the understanding of the structural changes of plant cells with giant polytene chromosomes during PCD.
Pregnancies complicated by the placenta praevia are associated with an increased risk of massive obstetric bleeding and high rates of hysterectomy which are often caused by the placenta accreta. The ...aim of our study was to identify the risk factors for placenta praevia associated with PAS disorders and the efficacy of distal haemostasis during Cesarean delivery.
This was a cohort study carried out between 2014 and 2020 in 532 women with abnormal placental localization and attachment. The placental attachment spectrum (PAS) disorder diagnosis was confirmed during the surgery and by the histology results in 164/532 participants. Depending on the surgical approach during the Cesarean delivery, patients were divided into three groups. In Group 1 (n = 52), patients underwent bilateral uterine artery ligation. In Group 2 (n = 33), we used the combined compression haemostasis approach including the placement of tourniquets and insertion of an intrauterine balloon for controlled tamponade. In Group 3 (n = 79), we used the combination of surgical haemostasis with the controlled intrauterine tamponade using the vaginal and intrauterine Zhukovsky balloon.
PAS was observed in 30.8% of the placenta praevia cases, and in 93.3% was associated with the presence of a uterine scar. Women with the placenta praevia and PAS had a significantly higher number of past deliveries (р = .001). According to the FIGO classification, 53.8% of women with placenta praevia observed during the Cesarean had РА1 and 46.2% PA2. With regards to the PAS disorders observed in 30.8% of patients, 38.4% had PAS3, 34.7% PAS4, 18.3% PAS5 and 8.5% PAS6. The histology analysis showed normal placental attachment in 42.9% of the total number of study participants, placenta accreta in 28.2%, placenta increta in 16.7%, and placenta percreta in 12.2%. In Group 1, we performed the resection of uterine wall with the attached portion of the placenta in 13.5% of women, in Group 2 in 30.3% women, and in Group 3 in 50.6% women. There was a significant 4.8-fold reduction in the number of hysterectomies in Group 3 versus Group 2 (р = .043) and a 4.4-fold reduction in Group 2 versus Group 1 (р = .003). In Group 2, the volume of blood loss was 1.3-fold lower and in Group 3 1.5-fold lower than in Group 1. Conclusion: The techniques of compression distal haemostasis evaluated in this study in women with PAS are efficacious in the reduction of adverse maternal outcomes and should be used more widely in clinical practice.
Pregnant women with chronic genital and non-genital infections are at a high risk of infections complication during pregnancy and the postpartum period. Preterm birth is one of the leading causes of ...obstetric and neonatal complications and occurs in one in nine women. Forty per cent of preterm births are considered to be caused by the abnormal vaginal microbiome, and there is currently no consensus on the contribution of combined bacterial and viral infections.
To assess the course of pregnancy and delivery in women with a high risk of chronic infections and the association with the presence of specific microorganisms in the genital microbiome.
We performed a prospective controlled observational study in 355 pregnant women with a high risk of chronic infections. The high risk was defined as presence acute or chronic genital or extragenital infections, reactivation of chronic infections/inflammatory diseases during current pregnancy and history of obstetric complications during previous pregnancies such as miscarriages, missed miscarriages, preterm deliveries, postpartum endometritis, and sepsis.
In women with a high risk of chronic infections, pregnancy was associated with recurrent threatened pregnancy loss (49.8%), preterm premature rupture of fetal membranes (64.3%), followed by prolonged oligohydramnios. Almost in one in two women (47.9%), pregnancy resulted in the delivery of preterm, low-birth-weight neonates. One in three women (30%) experienced uterine hypotony and bleeding after vaginal and cesarean delivery. Almost a third of women (32.1%) developed inflammatory complications postpartum, and more than half of complications (54.4%) was observed in women giving birth prematurely. Vaginal and cervical cultures in women who experienced preterm birth were dominated by non-obligate pathogens. We observed persistence of the Herpesviridae family both in the cervical canal and uterine cavity, specifically the Epstein-Barr virus (17.2%; 95% CI: 10%, 26.8%).
Pregnancies in women with a high risk of chronic infections were associated with high rates of recurrent threatened pregnancy loss, preterm rupture of membranes and preterm delivery.
The increase of luminosity of the SPS beams expected after 2020 allows considering the investigation of rather rare processes. In particular, so-called cumulative particle production can be studied ...in hadron collisions by measurements of secondary particle yields in regions kinematically forbidden for reactions with free nucleons. Such processes could be either a result of hard parton collisions with some large-density multi-quark configuration or of the formation of heavy baryonic resonances. Measurements in the backward hemisphere in fixed target experiment should provide the event-by-event data that could be used, along with those from the forward region, for a correlation analysis, thus resulting in new constraints on models. In this report the preliminary design, ideas, technology and the first GEANT simulations of a proposed new detector are presented and discussed.
This paper presents measurements of production cross sections and inelastic cross sections for the following reactions: 60 GeV/c protons with C, Be, Al targets and 120 GeV/c protons with C and Be ...targets. The analysis is performed using the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. First measurements are obtained using protons at 120 GeV/c, while the results for protons at 60 GeV/c are compared with previously published measurements. These interaction cross section measurements are critical inputs for neutrino flux prediction in current and future accelerator-based long-baseline neutrino experiments.
Magnetic properties of an interface between cobalt and platinum or tantalum nanolayers have been studied by the optical second-harmonic generation and nonlinear magneto-optical Kerr effect methods. ...It has been shown that a high sensitivity of the second-harmonic generation method makes it possible to determine the orientation of the easy magnetization axis in the plane of a polycrystalline structure without measurement of the magnetic field dependence of second-harmonic generation. The comparison of the field dependences of magnetic-field-induced second-harmonic generation with the linear magneto-optical effect indicates the difference in the processes of magnetization reversal in Co/Pt and Co/Ta interfaces and the bulk of the cobalt film. In particular, a new linear in magnetization effect has been observed in the second harmonic that is symmetry-forbidden for uniformly magnetized structures.
The production of
K
S
0
mesons in inelastic
p+p
collisions at beam momentum 158
GeV
/
c
(
s
NN
=
17.3
GeV
) was measured with the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. ...Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicity of
K
S
0
was determined to be
0.162
±
0.001
(
s
t
a
t
.
)
±
0.011
(
s
y
s
.
)
. The results on
K
S
0
production are compared with model predictions (
EPOS 1.99
, SMASH 2.0, PHSD and UrQMD 3.4 models) as well as with published world data.
To identify risk factors and predictors of pregnancy loss and to compare the efficacy of Arabin's pessary with cervical cerclage in women at a high risk of pregnancy loss.
This was a two-center ...retrospective case-control study that included 240 women at a high risk of preterm delivery. Group I (n = 161) included women who underwent insertion of the Arabin's pessary between 14 and 24 weeks of pregnancy. Group II (n = 79) included women who had undergone circular cervical cerclage during the current pregnancy. All women included in the study received micronized vaginal progesterone at the dose of 200 mg/day until and including 34 weeks of gestation.
Threatened pregnancy loss defined as spotting or vaginal bleeding in the first trimester was diagnosed in 29.8% (48/161) of patients in Group I versus 37.9% in Group II (p = .448). Postpartum bleeding occurred in 8.1% (13/161) in women in Group I versus 22.8% in Group II (χ
2
= 6.500; p = .011). Our study showed that cervical cerclage was most suitable for patients with history of obstetric complications, cervical length <15 mm, and large isthmic uterine fibroids. The use of the Arabin's pessary reduced the rate of preterm births by 1.7-fold. A cluster analysis demonstrated that predictors of preterm birth in women with a high risk of pregnancy loss included: threatened pregnancy loss associated with chorionic/placental abruption, cervical incompetence, uterine fibroid growth to a large size, history of multiple spontaneous pregnancy losses, cervical tears during past labor, and gestational diabetes diagnosed for the first time during the current pregnancy.
Women with a high risk of pregnancy loss treated with Arabin's pessary or cerclage plus vaginal progesterone had a term delivery rate of 70.4% (169/240). The combined strategy of pregnancy management allowed to markedly reduce the number of preterm births.
The optimal set of prospecting methods, including geophysical (geoelectrical), geological (mineralogical-geochemical), and hydrological observations, was developed during the long-term investigations ...of the sulfide mineralization in the northern equatorial zone of the Mid-Atlantic Ridge. The application of these methods made it possible to discover six massive sulfide deposits and considerably extend the boundaries of another two ore objects. The ores associated with ultramafic rocks are characterized by elevated Cu, Au, and Co concentrations. It is established that the ore formation was a multistage process that resulted in the accumulation of large deposits (over 10 million tons).
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