83 research outputs found
Team performance during vacuum-assisted vaginal delivery: video review of obstetric multidisciplinary teams
IntroductionVacuum extraction is generally considered an operator-dependent task, with most attention directed toward the obstetrician’s technical abilities (1–3). Little is known about the effect of the team and non-technical skills on clinical outcomes in vacuum-assisted delivery. This study aimed to investigate whether the non-technical skills of obstetricians were correlated with their level of clinical performance via the analysis of video recordings of teams conducting actual vacuum extractions.MethodsWe installed between two or three video cameras in each delivery room at Aarhus University Hospital and Horsens Regional Hospital and obtained 60 videos of teams managing vacuum extraction. Appropriate consent was obtained. Two raters carefully reviewed the videos and assessed the teams’ non-technical skills using the Assessment of Obstetric Team Performance (AOTP) checklist, rating all items on a Likert scale score from 1 to 5 (1 = poor; 3 = average; and 5 = excellent). This resulted in a total score ranging from 18 to 90. Two different raters independently assessed the teams’ clinical performance (adherence to clinical guidelines) using the TeamOBS-Vacuum-Assisted Delivery (VAD) checklist, rating each item (0 = not done, 1 = done incorrectly; and 2 = done correctly). This resulted in a total score with the following ranges (low clinical performance: 0–59; average: 60–84; and high: 85–100). Interrater agreement was analyzed using intraclass correlation (ICC), and the risk of high or low clinical performance was analyzed on a logit scale to meet the assumption of normality.ResultsTeams that received excellent non-technical scores had an 81% probability of achieving high clinical performance, whereas this probability was only 12% among teams with average non-technical scores (p < 0.001). Teams with a high clinical performance often had excellent behavior in the non-technical items of “team interaction,” “anticipation,” “avoidance fixation,” and “focused communication.” Teams with a low or average clinical performance often neglected to consider analgesia, had delayed abandonment of the attempted vaginal delivery and insufficient use of appropriate fetal monitoring. Interrater reliability was high for both rater-teams, with an ICC for the non-technical skills of 0.83 (95% confidence interval [CI]: 0.71–0.88) and 0.84 for the clinical performance (95% CI: 0.74–0.90).ConclusionAlthough assisted vaginal delivery by vacuum extraction is generally considered to be an operator-dependent task, our findings suggest that teamwork and effective team interaction play crucial roles in achieving high clinical performance. Teamwork helped the consultant anticipate the next step, avoid fixation, ensure adequate analgesia, and maintain thorough fetal monitoring during delivery
Humanized NOG Mice for Intravaginal HIV Exposure and Treatment of HIV Infection
Humanized mice provide a sophisticated platform to study human immunodeficiency virus (HIV) virology and to test antiviral drugs. This protocol describes the establishment of a human immune system in adult NOG mice. Here, we explain all the practical steps from isolation of umbilical cord blood derived human CD34+ cells and their subsequent intravenous transplantation into the mice, to the manipulation of the model through HIV infection, combination antiretroviral therapy (cART), and blood sampling. Approximately 75,000 hCD34+ cells are injected intravenously into the mice and the level of human chimerism, also known as humanization, in the peripheral blood is estimated longitudinally for months by flow cytometry. A total of 75,000 hCD34+ cells yields 20%–50% human CD45+ cells in the peripheral blood. The mice are susceptible to intravaginal infection with HIV and blood can be sampled once weekly for analysis, and twice monthly for extended periods. This protocol describes an assay for quantification of plasma viral load using droplet digital PCR (ddPCR). We show how the mice can be effectively treated with a standard-of- care cART regimen in the diet. The delivery of cART in the form of regular mouse chow is a significant refinement of the experimental model. This model can be used for preclinical analysis of both systemic and topical pre-exposure prophylaxis compounds as well as for testing of novel treatments and HIV cure strategies
Collagen concentration and biomechanical properties of samples from the lower uterine cervix in relation to age and parity in non-pregnant women
<p>Abstract</p> <p>Background</p> <p>During normal pregnancy the cervix has a load bearing function. The cervical tissue consists mainly of an extracellular matrix (ECM) rich in collagen; important for the biomechanical properties. The aim of the present study was to evaluate how the biomechanical strength of samples from the distal cervix is associated with collagen content in relation to age and parity. This study demonstrates a method to investigate cervical tissue from women who still have their uterus in situ.</p> <p>Methods</p> <p>Cervical punch biopsies (2 × 15 mm) were obtained from 57 healthy women (median age: 39 years, range: 29-49 years). Biomechanical tensile testing was performed, and collagen concentration (as % of dry defatted weight (DDW)) and content (mg of collagen per mm of specimen length) was determined. Histomorphometry was used to determine the volume densities of extracellular matrix and smooth muscle cells. Smooth muscle cells were identified by immunohistochemistry. Finally, orientation of collagen fibers was estimated. Data are given as mean +/- SD.</p> <p>Results</p> <p>The mean collagen concentration (62.2 +/- 6.6%) increased with age (0.5% per year, r = 0.45, p = 0.003) and decreased with parity (1.7% per birth, r = -0.45, p = 0.033). Maximum load was positively correlated with collagen content (mg of collagen per mm of specimen length) (r = 0.76, p < 0.001). Normalized maximum stiffness was increased with age (r = 0.32, p = 0.017), whereas no correlation was found with regard to parity. In tissue samples with a length of approximately one cm, volume density of smooth muscle cells increased gradually from 8.9% in the distal part near the epithelium, to 15.5% in the proximal part (p < 0.001).</p> <p>Conclusions</p> <p>The present study shows that cervical collagen concentration increases with age and decreases with parity in non-pregnant women. In addition, collagen stiffness increased with age, whereas no change in collagen tensile strength with respect to age and parity was found. These results show that collagen contributes to cervical tissue tensile strength and age and parity should be considered confounding factors.</p
Interferon priming is essential for human CD34+ cell-derived plasmacytoid dendritic cell maturation and function
Plasmacytoid dendritic cells (pDC) are essential for immune competence. Here we show that pDC precursor differentiated from human CD34+ hematopoietic stem and progenitor cells (HSPC) has low surface expression of pDC markers, and has limited induction of type I interferon (IFN) and IL-6 upon TLR7 and TLR9 agonists treatment; by contrast, cGAS or RIG-I agonists-mediated activation is not altered. Importantly, after priming with type I and II IFN, these precursor pDCs attain a phenotype and functional activity similar to that of peripheral blood-derived pDCs. Data from CRISPR/Cas9-mediated genome editing of HSPCs further show that HSPC-pDCs with genetic modifications can be obtained, and that expression of the IFN-α receptor is essential for the optimal function, but dispensable for the differentiation, of HSPC-pDC percursor. Our results thus demonstrate the biological effects of IFNs for regulating pDC function, and provide the means of generating of gene-modified human pDCs
Balance between matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) in the cervical mucus plug estimated by determination of free non-complexed TIMP
<p>Abstract</p> <p>Background</p> <p>The cervical mucus plug (CMP) is a semi-solid structure with antibacterial properties positioned in the cervical canal during pregnancy. The CMP contains high concentrations of matrix metalloproteinase 8 and 9 (MMP-8, MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1). This indicates a potential to degrade extracellular matrix components depending on the balance between free non-complexed inhibitors and active enzymes.</p> <p>Methods</p> <p>Thirty-two CMPs collected during active labor at term were analyzed. Twelve CMPs were separated into a cellular and an extracellular/fluid phase and analyzed by gelatin and reverse zymography to reveal MMP and TIMP location. Twenty samples were homogenized, extracted and studied by the TIMP activity assay based on gelatin zymography. Enzyme-linked immunosorbent assay (ELISA) was used to determine TIMP-1, MMP-8 and MMP-9 protein concentrations, and gelatin and reverse zymography used to identify gelatinases and TIMPs, respectively. The Western blotting technique was applied for semi-quantification of alpha2-macroglobulin. An ELISA activity assay was used to detect MMP-8 and MMP-9 activity.</p> <p>Results</p> <p>ProMMP-2, proMMP-9, TIMP-1 and TIMP-2 were almost exclusively located in the fluid phase compared to the cellular phase of the CMP. All the extracted samples contained MMP-8, MMP-9, TIMP-1, TIMP-2 and alpha2-macroglobulin. Free non-complexed TIMP was detected in all the samples analyzed by the TIMP activity assay and was associated with TIMP-1 protein (R = 0.71, p < 0.001) and with the TIMP/MMP molar ratio (1.7 (1.1–2.5) (mean (95% confidence interval)) (R = 0.65, p = 0.002). The ELISA activity assay showed no activity from MMP-8 or MMP-9.</p> <p>Conclusion</p> <p>Due to their extracellular location, potential proteolytic activity from neutrophil-derived MMPs in the CMP could exert a biological impact on cervical dilatation and fetal membrane rupture at term. The functional TIMP activity assay, revealing excess non-complexed TIMP, and a molar inhibitor/enzyme ratio above unity, indicate that refined MMP control prevents CMP-originated proteolytic activity in the surrounding tissue.</p
High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis
Collagen synthesis is severely diminished in osteoarthritis; thus, enhancing it may help the regeneration of cartilage. This
requires large amounts of glycine, proline and lysine. Previous works of our group have shown that glycine is an essential
amino acid, which must be present in the diet in large amounts to satisfy the demands for collagen synthesis. Other authors
have shown that proline is conditionally essential. In this work we studied the effect of these amino acids on type II collagen
synthesis. Bovine articular chondrocytes were cultured under a wide range of different concentrations of glycine, proline and
lysine. Chondrocytes were characterized by type II collagen immunocytochemistry of confluence monolayer cultures. Cell
growth and viability were assayed by trypan blue dye exclusion method. Type II collagen was measured in the monolayer,
every 48 h for 15 days by ELISA. Increase in concentrations of proline and lysine in the culture medium enhances the synthesis
of type II collagen at low concentrations, but these effects decay before 1.0 mM. Increase of glycine as of 1.0 mM
exceeds these effects and this increase continues more persistently by 60–75%. Since the large effects produced by proline
and lysine are within the physiological range, while the effect of glycine corresponds to a much higher range, these results
demonstrated a severe glycine deficiency for collagen synthesis. Thus, increasing glycine in the diet may well be a strategy
for helping cartilage regeneration by enhancing collagen synthesis, which could contribute to the treatment and prevention
of osteoarthriti
Corticotropin-releasing hormone, its binding protein and receptors in human cervical tissue at preterm and term labor in comparison to non-pregnant state
BACKGROUND: Preterm birth is still the leading cause of neonatal morbidity and mortality. The level of corticotropin-releasing hormone (CRH) is known to be significantly elevated in the maternal plasma at preterm birth. Although, CRH, CRH-binding protein (CRH-BP), CRH-receptor 1 (CRH-R1) and CRH-R2 have been identified both at mRNA and protein level in human placenta, deciduas, fetal membranes, endometrium and myometrium, no corresponding information is yet available on cervix. Thus, the aim of this study was to compare the levels of the mRNA species coding for CRH, CRH-BP, CRH-R1 and CRH-R2 in human cervical tissue and myometrium at preterm and term labor and not in labor as well as in the non-pregnant state, and to localize the corresponding proteins employing immunohistochemical analysis. METHODS: Cervical, isthmic and fundal (from non-pregnant subjects only) biopsies were taken from 67 women. Subjects were divided in 5 groups: preterm labor (14), preterm not in labor (7), term labor (18), term not in labor (21) and non-pregnant (7). Real-time RT-PCR was employed for quantification of mRNA levels and the corresponding proteins were localized by immunohistochemical analysis. RESULTS: The levels of CRH-BP, CRH-R1 and CRH-R2 mRNA in the pregnant tissues were lower than those in non-pregnant subjects. No significant differences were observed between preterm and term groups. CRH-BP and CRH-R2 mRNA and the corresponding proteins were present at lower levels in the laboring cervix than in the non-laboring cervix, irrespective of gestational age. In most of the samples, with the exception of four myometrial biopsies the level of CRH mRNA was below the limit of detection. All of these proteins could be detected and localized in the cervix and the myometrium by immunohistochemical analysis. CONCLUSION: Expression of CRH-BP, CRH-R1 and CRH-R2 in uterine tissues is down-regulated during pregnancy. The most pronounced down-regulation of CRH-BP and CRH-R2 occurred in laboring cervix, irrespective the length of gestation. The detection of substantial expression of the CRH and its receptor proteins, as well as receptor mRNA in the cervix suggests that the cervix may be a target for CRH action. Further studies are required to elucidate the role of CRH in cervical ripening
Impaired leukocyte influx in cervix of postterm women not responding to prostaglandin priming
<p>Abstract</p> <p>Background</p> <p>Prolonged pregnancies are associated with increased rate of maternal and fetal complications. Post term women could be divided into at least two subgroups, one where parturition is possible to induce by prostaglandins and one where it is not. Our aim was to study parameters in cervical biopsies in women with spontaneous delivery at term (controls) and compare to those that are successfully induced post term (responders), and those that are not induced (non-responders), by local prostaglandin treatment.</p> <p>Methods</p> <p>Stromal parameters examined in this study were the accumulation of leukocytes (CD45, CD68), mRNAs and/or proteins for the extracellular matrix degrading enzymes (matrix metalloproteinase (MMP)-2, MMP-8 and MMP-9), their inhibitors (tissue inhibitor of MMP (TIMP)-1 and TIMP-2), interleukin-8 (IL-8), the platelet activating factor-receptor (PAF-R), syndecan-1 and estrogen binding receptors (estrogen receptor (ER)α, ERβ and G-coupled protein receptor (GPR) 30) as well as the proliferation marker Ki-67.</p> <p>Results</p> <p>The influx of leukocytes as assessed by CD45 was strongest in the responders, thereafter in the controls and significantly lower in the non-responders. IL-8, PAF-R and MMP-9, all predominantly expressed in leukocytes, showed significantly reduced immunostaining in the group of non-responders, while ERα and GPR30 were more abundant in the non-responders, as compared to the controls.</p> <p>Conclusion</p> <p>The impaired leukocyte influx, as reflected by the reduced number of CD45 positive cells as well as decreased immunostaining of IL-8, PAF-R and MMP-9 in the non-responders, could be one explanation of the failed ripening of the cervix in post term women. If the decreased leukocyte influx is a primary explanation to absent ripening or secondary, as a result of other factors, is yet to be established.</p
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