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ABSTRACT: Hydraulic fractures generated by fluid injection in rock formations are often mapped by seismic monitoring. In many cases, the microseismicity is asymmetric relative to the injection well, which has been interpreted by stress gradient along the direction of the hydraulic fracture. We present a mathematical model of asymmetric hydrofracture growth based on relations between the solid‐phase stress and the fracture hydraulics. For single fracture and single injection point, the model has three parameters, hydraulic conductivities of the fracture wings, and normalised stress gradient and predicts the positions of the fracture tips as functions of time. The model is applied to a set of microseismic event locations that occurred during and after an injection process. Two different methods are suggested that make it possible to delineate the fracture tips from the set of microseismic events. This makes it possible to determine the model parameters and to check the agreement between the model prediction and the measured data. The comparison of the measured and modelled growth of fracture wings supports both the assumption of the non‐zero stress gradient and the existence of the post‐injection unilateral growth. [ABSTRACT FROM AUTHOR]

The process of sedimentation and subsequent gravity compression of kaolin and water suspensions was investigated experimentally. 45 batch tests were carried out and the time dependence of the height of the suspension column was measured. The one-dimensional equations of Darcian mechanics of two-phase porous media are applied to formulate the studied process mathematically. A very natural assumption makes it possible to find a solution of the forward problem for a starting period of the process. Analysis of the theoretical function and the experimental data gives hydraulic conductivity as a function of the suspension concentration. The obtained results are presented and discussed.

Objective: The absence of microbial invasion of the amniotic cavity and intra-amniotic inflammation at the time of hospital admission is the most common condition associated with preterm prelabor rupture of membranes (PPROM). Although the intensity of intra-amniotic inflammatory response does not exceed the threshold for the diagnosis of intra-amniotic inflammation in this subgroup of PPROM, whether there could be differences in outcomes concerning the intensity of intra-amniotic inflammatory response remains unclear. Therefore, the main aims of this study on PPROM without microbial invasion of the amniotic cavity and intra-amniotic inflammation were (i) to characterize the association between the intensity of intra-amniotic inflammatory response, measured according to amniotic fluid interleukin (IL)-6 concentrations, and the presence of acute histological chorioamnionitis and acute inflammation in the amnion; (ii) to characterize the association between the intensity of intra-amniotic inflammatory response and fetal inflammatory response, and (iii) to describe the short-term morbidity of infants based on the intensity of intra-amniotic inflammatory response., Methods: This retrospective study included 131 women with singleton pregnancies with PPROM without microbial invasion of the amniotic cavity and intra-amniotic inflammation between gestational ages of 24 + 0 and 36 + 6 weeks and who had delivered within 72 h of membrane rupture. Microbial invasion of the amniotic cavity was assessed based on a combination of cultivation and non-cultivation methods. Intra-amniotic inflammation was characterized based on the amniotic fluid IL-6 concentration. In addition, a histopathological assessment of the placenta was performed. Fetal inflammatory response syndrome was characterized according to IL-6 concentration in the umbilical cord blood of >11 pg/mL. Based on the quartiles of IL-6 concentrations in the amniotic fluid, these women were divided into four subgroups (from the lowest to the highest IL-6 concentrations)., Results: IL-6 concentrations in amniotic fluid were higher in women with acute histological chorioamnionitis (median: 819 pg/mL vs. 520 pg/mL; p  = .003) and with acute inflammation of the amnion (median: 1116 pg/mL vs. 533 pg/mL; p  = .0002) than in women without these complications. The rates of acute histological chorioamnionitis and acute inflammation of the amnion were the highest in the subgroup with IL-6 concentrations above the 75th percentile in amniotic fluid (chorioamnionitis, p  = .02; amnion, p  = .0002). No differences in IL-6 concentrations in amniotic fluid were identified between women with and without a fetal inflammatory response syndrome ( p  = .40). The rate of fetal inflammatory response syndrome did not vary among the amniotic fluid IL-6 quartile subgroups of women. Moreover, no differences were noted in short-term neonatal outcomes among the amniotic fluid IL-6 quartile subgroups., Conclusion: A higher intensity of the intra-amniotic inflammatory response, measured by amniotic fluid IL-6 concentrations, is associated with a higher rate of acute inflammatory lesions in the placenta in the subset of PPROM pregnancies without microbial invasion of the amniotic cavity and intra-amniotic inflammation.

Objectives: To determine the prevalence and load of Ureaplasma spp. DNA in the cervical fluid of women with singleton pregnancies complicated by preterm prelabor rupture of membranes (PPROM) with respect to intra-amniotic infection, sterile intra-amniotic inflammation, and colonization of the amniotic fluid. Methods: A total of 217 women with PPROM between gestational ages 24 + 0 and 33 + 6 weeks were included in this study. Paired amniotic and cervical fluid samples were collected at the time of admission via transabdominal amniocentesis and using a Dacron polyester swab, respectively. Microbial invasion of the amniotic cavity was diagnosed using a combination of culture and molecular biology methods. Intra-amniotic inflammation was determined based on the concentration of interleukin-6 in the amniotic fluid. Based on the presence or absence of these conditions, the women were stratified into the following subgroups: intra-amniotic infection (with both), sterile intra-amniotic inflammation (with inflammation only), colonization (with microorganisms only), and negative amniotic fluid (without either). The Ureaplasma spp. DNA load in the cervical fluid was assessed using PCR. Results: Ureaplasma spp. DNA in the cervical fluid was found in 61% (133/217) of the women. Women with negative amniotic had similar prevalence of Ureaplasma spp. DNA in cervical fluid (55%) to those with sterile intra-amniotic inflammation (54%) but lower than those with intra-amniotic infection (73%) and colonization (86%; p < 0.0001). Women with negative amniotic fluid had a lower load of Ureaplasma spp. DNA in their cervical fluid (median: 4.7 × 10 3 copies of DNA/ml) than those with intra-amniotic infection (median: 2.8 × 10 5 copies DNA/ml), sterile intra-amniotic inflammation (median: 5.3 × 10 4 copies DNA/ml), and colonization (median: 1.2 × 10 5 copies DNA/mL; p < 0.0001). Conclusion: In conclusion, in PPROM at <34 weeks, the presence of intra-amniotic infection, sterile intra-amniotic inflammation, or colonization of the amniotic fluid was associated with a higher prevalence and/or load of Ureaplasma spp. DNA in the cervical fluid than the absence of intra-amniotic complications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kacerovsky, Kukla, Bolehovska, Bostik, Matulova, Mls, Stranik, Jacobsson and Musilova.)

To determine the main clinical characteristics of preterm prelabor rupture of membranes (PPROM) complicated by colonization of the amniotic cavity (microbial invasion of the amniotic cavity without intra-amniotic inflammation). A total of 302 women with PPROM were included. Transabdominal amniocentesis was performed and amniotic fluid was assessed. Based of microbial invasion of the amniotic cavity and intra-amniotic inflammation (interleukin-6 ≥ 3000 pg/mL), the women were divided into following groups: intra-amniotic infection, sterile intra-amniotic inflammation, colonization of the amniotic cavity, and negative amniotic fluid. Colonization was found in 11% (32/302) of the women. The most common bacteria identified in the amniotic fluid were Ureaplasma spp. with a lower burden than those with intra-amniotic infection (p = 0.03). The intensity of intra-amniotic inflammatory response measured by interleukin-6 was higher in women with colonization than in those with negative amniotic fluid (medians: 961 pg/mL vs. 616 pg/mL; p = 0.04). Women with colonization had higher rates of acute inflammatory placental lesions than those with negative amniotic fluid. In PPROM, colonization, caused mainly by microorganisms from the lower genital tract, might represent an early stage of microbial invasion of the amniotic cavity with a weak intra-amniotic inflammatory response., (© 2022. The Author(s).)

Aim: To assess the association between the birth weight of newborns from pregnancies with preterm prelabor rupture of membranes (PPROM) and the presence of acute histological chorioamnionitis (HCA) with respect to the: i) fetal and maternal inflammatory responses and ii) acute inflammation of the amnion. Material and Methods: This retrospective cohort study included 818 women with PPROM. A histopathological examination of the placenta was performed. Fetal inflammatory response was defined as the presence of any neutrophils in umbilical cord (histological grades 1-4) and/or chorionic vasculitis (histological grade 4 for the chorionic plate). Maternal inflammatory response was defined as the presence of histological grade 3-4 for the chorion-decidua and/or grade 3 for the chorionic plate and/or grade 1-4 for the amnion. Acute inflammation of the amnion was defined as the presence of any neutrophils in the amnion (histological grade 1-4 for the amnion). Birth weights of newborns were expressed as percentiles derived from INTERGROWTH-21st standards for the i) estimated fetal weight and ii) newborn birth weight. Results: No difference in percentiles of birth weights of newborns was found among the women with the women with HCA with fetal inflammatory response, with HCA with maternal inflammatory response and those without HCA. Women with HCA with acute inflammation of the amnion had lower percentiles of birth weights of newborns, derived from the estimated fetal weight standards, than women with HCA without acute inflammation of the amnion and those with the absence of HCA in the crude (with acute inflammation: median 46, without acute inflammation: median 52, the absence of HCA: median 55; p = 0.004) and adjusted ( p = 0.02) analyses. The same subset of pregnancies exhibited the highest rate of newborns with a birth weight of ≤25 percentile. When percentiles were derived from the newborn weight standards, no differences in birth weights were observed among the subgroups. Conclusion: Acute inflammation of the amnion was associated with a lower birth weight in PPROM pregnancies, expressed as percentiles derived from the estimated fetal weight standards., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Matulova, Kacerovsky, Hornychova, Stranik, Mls, Spacek, Burckova, Jacobsson and Musilova.)

Objective: To determine the association between microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation (IAI) and the cervical prevalence of Gardnerella vaginalis DNA in pregnancies with preterm prelabor rupture of membrane (PPROM)., Method: In total, 405 women with singleton pregnancies complicated with PPROM were included. Cervical fluid and amniotic fluid samples were collected at the time of admission. Bacterial and G. vaginalis DNA were assessed in the cervical fluid samples using quantitative PCR technique. Concentrations of interleukin-6 and MIAC were evaluated in the amniotic fluid samples. Loads of G. vaginalis DNA ≥ 1% of the total cervical bacterial DNA were used to define the cervical prevalence of G. vaginalis as abundant. Based on the MIAC and IAI, women were categorized into four groups: with intra-amniotic infection (both MIAC and IAI), with sterile IAI (IAI without MIAC), with MIAC without IAI, and without either MIAC or IAI., Results: The presence of the abundant cervical G. vaginalis was related to MIAC (with: 65% vs. without: 44%; p = 0.0004) but not IAI (with: 52% vs. without: 48%; p = 0.70). Women with MIAC without IAI had the highest load of the cervical G. vaginalis DNA (median 2.0 × 104 copies DNA/mL) and the highest presence of abundant cervical G. vaginalis (73%)., Conclusions: In women with PPROM, the presence of cervical G. vaginalis was associated with MIAC, mainly without the concurrent presence of IAI., Competing Interests: The authors have declared that no competing interests exist.

Background: To determine the association between microbial invasion of the amniotic cavity (MIAC) and the presence of Lactobacillus crispatus- or Lactobacillus iners-dominated cervical microbiota in pregnancies with preterm prelabor rupture of membrane. Next, to assess the relationship between the presence of L. crispatus- or L. iners-dominated cervical microbiota and short-term neonatal morbidity., Method: A total of 311 women were included. Cervical samples were obtained using a Dacron polyester swab and amniotic fluid samples were obtained by transabdominal amniocentesis. Bacterial DNA, L. crispatus, and L. iners in the cervical samples were assessed by PCR. Cervical microbiota was assigned as L. crispatus- or L. iners-dominated when the relative abundance of L. crispatus or L. iners was ≥50% of the whole cervical microbiota, respectively., Results: Women with MIAC showed a lower rate of L. crispatus-dominated cervical microbiota (21% vs. 39%; p = 0.003) than those without MIAC. Lactobacillus crispatus-dominated cervical microbiota was associated with a lower rate of early-onset sepsis (0% vs. 5%; p = 0.02)., Conclusions: The presence of L. crispatus-dominated cervical microbiota in women with preterm prelabor rupture of membrane was associated with a lower risk of intra-amniotic complications and subsequent development of early-onset sepsis of newborns.

Objective: To summarize current knowledge regarding Lactobacillus iners-dominated vaginal microbiota in pregnancy, as well as an association between the presence of Lactobacillus iners and pregnancy complications Type of study: Review., Setting: Department of Obstetrics and Gynecology, University Hospital Hradec Kralove, Charles University, Faculty of Medicine in Hradec Kralove., Methods and Results: In this review, the results from literature available about the presence of L. iners-dominated microbiota in pregnancy and the association between the presence of L. iners-dominated microbiota and abortion, spontaneous preterm delivery with intact membranes, and preterm prelabor rupture of membranes are summarized., Conclusion: L. iners-dominated vaginal microbiota appears to be associated with an increased risk of the development of specific pregnancies pathologies.

The roles of autophagic cell death and apoptosis induced by topoisomerase inhibitor irinotecan in colon cancer cells with deleted p53 were investigated during 48 h. We report that irinotecan-dependent cytotoxicity and proapoptotic activity were reduced in the present model while autophagy levels significantly increased. Upon p53 transfection, cell demise rates increased, with cells bearing the features of apoptosis and autophagic cell death. The subsequent studies into mechanisms of cell death process revealed the important role of Bax in mediating mitochondrial and lysosomal leakage which might serve as leading signals for both apoptosis and autophagic cell death. These results suggest that different modes of cell death in p53 null colon cancer cells treated with cytostatics (irinotecan) may be activated simultaneously. Moreover, their interactions possibly occur at several stages and aren't mutually exclusive. This might thus lead to a potential synergism with interesting therapeutic ramifications.

Regulations for the sealing of landfill sites require two independent sealing components. To satisfy this requirement, the combined capillary barrier was developed using impermeable sheeting placed between the capillary layer and the capillary block of the traditional capillary barrier. In this study, a numerical model is introduced based on hydraulic characteristics obtained by means of measurements of samples of capillary barrier materials. To make a comparison possible, samples of a laboratory investigated barrier were measured. Two laboratory experiments with a simple and a combined capillary barrier were repeated using the developed numerical model and good agreement between computed and measured results was found. Subsequently, the model was used for investigating the effect of failure of the artificial sheeting on the capillary barrier's efficiency. The obtained results are presented and discussed.