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1.
Placenta ; 97: 79-88, 2020 08.
Article in English | MEDLINE | ID: mdl-32792069

ABSTRACT

INTRODUCTION: We use an in-vitro human fetal membrane (FM) explant-based model to study inflammation-induced FM weakening, a prerequisite for PPROM. In this system, GMCSF is a critical intermediate, both necessary and sufficient for TNFα and thrombin induced FM weakening. α-Lipoic-acid (LA) blocks TNFα and thrombin, as well as GMCSF-induced weakening. Recently, we reported LA concomitantly blocks GMCSF-induction of MMPs 2, 9 and 10 and inhibition of TIMPs 1-3. The aim of this study was to show that LA blocks GMCSF-induced increases in additional proteases and reductions in additional protease inhibitors. METHODS: FM fragments were cultured±LA and then±GMCSF. In other experiments, weak versus strong, fresh FM were cultured without additions. Fragments were strength tested and media analyzed by multiplex protein ELISA for proteases and protease inhibitors. RESULTS: GMCSF induced FM weakening and concomitantly increased several Proteases (Cathepsin-S, Proteinase-3, Elastase-2) and decreased several protease inhibitors (NGAL, Cystatin-C, HE4 and Thrombospondin1). LA inhibited GMCSF-induced FM weakening and all enzymatic changes. Untreated weaker versus stronger regions of fresh FM showed comparable differences in proteases and protease inhibitor patterns to GMCSF-stimulated versus controls. CONCLUSION: LA blocks GMCSF-induced human FM weakening and associated protease increases and inhibitor decreases. The GMCSF-induced spectrum of protease/protease-inhibitor changes is similar to that in the natural weak FM fragments. In concert with previously reported GMCSF-induced changes in MMPs & TIMPs, these other protease and protease-inhibitor changes presumably facilitate FM weakening and rupture. LA blocks these GMCSF effects and therefore may be a useful agent to prevent PPROM.


Subject(s)
Extraembryonic Membranes/drug effects , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Peptide Hydrolases/metabolism , Thioctic Acid/pharmacology , Cystatins/metabolism , Extraembryonic Membranes/metabolism , Female , Humans , Pregnancy , Thrombin/metabolism , Thrombospondin 1/metabolism , Tumor Necrosis Factor-alpha/metabolism
2.
Int J Lab Hematol ; 40(5): 533-539, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29806244

ABSTRACT

INTRODUCTION: Immunophenotyping by flow cytometry is routinely employed in distinguishing between chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). Inclusion of CD200 has been reported to contribute to more reliable differentiation between CLL and MCL. We investigated the value of CD200 in assessment of atypical CLL cases. METHODS: CD200 expression on mature B cell neoplasms was studied by eight-color flow cytometry in combination with a conventional panel of flow cytometry markers. The study included 70 control samples, 63 samples with CLL or atypical CLL phenotype, 6 MCL samples, and 40 samples of other mature B cell neoplasms. RESULTS: All CLL samples were positive for CD200, whereas MCL samples were dim or negative for CD200. Of the CLL samples, 7 were atypical by conventional flow cytometry, with Matutes scores ≤3. These cases were tested for evidence of a t(11;14) translocation, characteristic of MCL, and all were negative, consistent with their classification as atypical CLL. All these atypical CLL samples were strongly positive for CD200. CONCLUSION: CD200 proved to be a useful marker for differentiation between CLL and MCL by flow cytometry. In particular, CD200 was useful in distinguishing CLL samples with atypical immunophenotypes from MCL.

3.
Placenta ; 38: 57-66, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26907383

ABSTRACT

INTRODUCTION: Fetal membranes (FM) usually fail prior to delivery during term labor, but occasionally fail at preterm gestation, precipitating preterm birth. To understand the FM biomechanical properties underlying these events, study of the baseline in-vivo stretch experienced by the FM is required. This study's objective was to utilize high resolution MRI imaging to determine in-vivo FM stretch. METHODS: Eight pregnant women (38.4 ± 0.4wks) underwent abdominal-pelvic MRI prior to (2.88 ± 0.83d) caesarean delivery. Software was utilized to determine the total FM in-vivo surface area (SA) and that of its components: placental disc and reflected FM. At delivery, the SA of the disc and FM in the relaxed state were measured. In-vivo (stretched) to delivered SA ratios were calculated. FM fragments were then biaxially stretched to determine the force required to re-stretch the FM back to in-vivo SA. RESULTS: Total FM SA, in-vivo vs delivered, was 2135.51 ± 108.47 cm(2) vs 842.59 ± 35.86 cm(2); reflected FM was 1778.42 ± 107.39 cm(2) vs 545.41 ± 22.90 cm(2), and disc was 357.10 ± 28.08 cm(2) vs 297.18 ± 22.14 cm(2). The ratio (in-vivo to in-vitro SA) of reflected FM was 3.26 ± 0.11 and disc was 1.22 ± 0.10. Reflected FM re-stretched to in-vivo SA generated a tension of 72.26 N/m, corresponding to approximate pressure of 15.4 mmHg. FM rupture occurred at 295.08 ± 31.73 N/m corresponding to approximate pressure of 34 mmHg. Physiological SA was 70% of that at rupture. DISCUSSION: FM are significantly distended in-vivo. FM collagen fibers were rapidly recruited once loaded and functioned near the failure state during in-vitro testing, suggesting that, in-vivo, minimal additional (beyond physiological) stretch may facilitate rapid, catastrophic failure.


Subject(s)
Extraembryonic Membranes/physiology , Tensile Strength/physiology , Term Birth , Biomechanical Phenomena , Extraembryonic Membranes/diagnostic imaging , Female , Fetal Membranes, Premature Rupture/diagnostic imaging , Fetal Membranes, Premature Rupture/parasitology , Fetal Membranes, Premature Rupture/physiopathology , Gestational Age , Humans , Labor, Obstetric , Magnetic Resonance Imaging , Pregnancy , Stress, Mechanical
4.
Placenta ; 35(12): 1049-56, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25454284

ABSTRACT

INTRODUCTION: Inflammation/infection and decidual bleeding/abruption are highly associated with pPROM. As no animal model for pPROM exists, we have developed an in-vitro model system for the study of human fetal membrane (FM) weakening/rupture. Using it we have demonstrated that both TNF/IL-1 (modeling inflammation) and thrombin (modeling bleeding) weaken full thickness FM in a dose dependent manner concomitant with inducing biochemical changes similar to those seen in the FM physiological weak zone. METHODS: As the physiological site of infection and bleeding is the choriodecidua (CD), we modified our model system with full thickness FM tissue mounted on modified Transwell culture inserts to permit directional TNF/thrombin exposure on the decidua only (rather than both sides of the FM). After incubation, medium was sampled separately from the CD facing (maternal side) or from the amnion facing (fetal side) compartments and probed for cytokine release and confirmed with western blots. The FM was strength tested within the insert. RESULTS: Full-thickness FM fragments exposed to TNF or thrombin on CD side only showed dose dependent weakening and biochemical changes consistent with previous reports. Concomitantly, GM-CSF increased markedly on the CD but not the amnion side. Numerous proteases including MMP1 and MMP3 also increased on the CD side. Pre-incubation with GM-CSF antibody blocked both thrombin and TNF induced weakening. Finally, GM-CSF weakened FM in a dose dependent manner. DISCUSSION: GM-CSF is a critical common intermediate in the thrombin and TNF FM weakening pathways.


Subject(s)
Extraembryonic Membranes/drug effects , Fetal Membranes, Premature Rupture/metabolism , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Thrombin/pharmacology , Tumor Necrosis Factor-alpha/pharmacology , Animals , Extraembryonic Membranes/metabolism , Female , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Humans , Pregnancy , Thrombin/metabolism , Tumor Necrosis Factor-alpha/metabolism
5.
Placenta ; 34(10): 924-31, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23953865

ABSTRACT

INTRODUCTION: Preterm premature rupture of fetal membranes (pPROM) is a major cause of preterm birth. Abruption associated thrombin production, and infection-inflammation associated cytokine production reportedly play major roles in pPROM. Utilizing an in vitro model-system we have confirmed that both thrombin and inflammatory cytokines remodel and biomechanically weaken amnion, the load-bearing component of FM. Also, we have shown thrombin directly weakens isolated amnion but cytokines weaken amnion only indirectly by initially interacting with choriodecidua and releasing unidentified soluble activator(s). This study's purpose was to determine whether thrombin weakens the isolated amnion through thrombin receptor-protease activated receptors (PARs 1,2,3,4), activation of previously secreted extracellular matrix (ECM) enzymes, or by direct action on the ECM. METHODS: Primary amnion cells and isolated amnion were tested for PARs by immunohistochemistry, Western Blot and rtPCR. Cell-free amnion ECM was produced by devitalizing isolated amnion by exposure to UV light and subsequent freeze-thaw cycles. Devitalized amnion membrane explants were incubated with thrombin and biomechanically tested. RESULTS: PARs were not found in amnion or amnion cells. Thrombin induced dose-dependent weakening of devitalized amnion explants. Preincubation with the thrombin inhibitor hirudin prevented thrombin-induced weakening. Thrombin converted pro-MMP2 embedded in the devitalized amnion ECM to multiple active forms. Thrombin also directly digested gelatin gels in zymograms suggesting the possibility of direct degradation of amnion ECM components. DISCUSSION: Thrombin appears to directly weaken the amnion ECM and additionally activates stored pro-MMP2 to active forms that may further enhance amnion ECM degradation. CONCLUSION: Thrombin weakens amnion directly rather than through PARs.


Subject(s)
Amnion/physiology , Extracellular Matrix/physiology , Thrombin/metabolism , Amnion/drug effects , Extracellular Matrix/drug effects , Female , Fetal Membranes, Premature Rupture/etiology , Hirudins/pharmacology , Humans , Pregnancy , Receptors, Proteinase-Activated/metabolism , Thrombin/antagonists & inhibitors
6.
Bone Marrow Transplant ; 47(6): 770-90, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22002489

ABSTRACT

In 1997, the first consensus guidelines for haematopoietic SCT (HSCT) in autoimmune diseases (ADs) were published, while an international coordinated clinical programme was launched. These guidelines provided broad principles for the field over the following decade and were accompanied by comprehensive data collection in the European Group for Blood and Marrow Transplantation (EBMT) AD Registry. Subsequently, retrospective analyses and prospective phase I/II studies generated evidence to support the feasibility, safety and efficacy of HSCT in several types of severe, treatment-resistant ADs, which became the basis for larger-scale phase II and III studies. In parallel, there has also been an era of immense progress in biological therapy in ADs. The aim of this document is to provide revised and updated guidelines for both the current application and future development of HSCT in ADs in relation to the benefits, risks and health economic considerations of other modern treatments. Patient safety considerations are central to guidance on patient selection and HSCT procedural aspects within appropriately experienced and Joint Accreditation Committee of International Society for Cellular Therapy and EBMT accredited centres. A need for prospective interventional and non-interventional studies, where feasible, along with systematic data reporting, in accordance with EBMT policies and procedures, is emphasized.


Subject(s)
Autoimmune Diseases/therapy , Hematopoietic Stem Cell Transplantation/methods , Hematopoietic Stem Cell Transplantation/standards , Autoimmune Diseases/economics , Clinical Trials, Phase I as Topic , Clinical Trials, Phase II as Topic , European Union , Female , Hematopoietic Stem Cell Transplantation/economics , Humans , Male , Risk Factors , Safety , Severity of Illness Index
7.
Gynecol Obstet Fertil ; 39(6): 373-7, 2011 Jun.
Article in French | MEDLINE | ID: mdl-21602078

ABSTRACT

The purpose of this study was to determine the biomechanical characteristics of human fetal membranes (FM) throughout gestation. Biomechanical properties were determined for 115 FM of 23-41 weeks gestation using our previously described methodology. The areas of membrane immediately adjacent to the strongest and weakest tested spots were sampled for histomorphometric analysis. Clinical data on the patients whose FM were examined were also collected. FM less than 28 weeks gestation were associated with higher incidence of abruption and chorioamnionitis. Topographically FM at all gestations had heterogeneous biomechanical characteristics over their surfaces with distinct weak areas. The most premature membranes were the strongest. FM strength represented by rupture force and work to rupture decreased with increasing gestation in both weak and strong regions of FM. This decrease in FM strength was most dramatic at more than 38 weeks gestation. The FM component amnion-chorion sublayers were thinner in the weak areas compared to strong areas. Compared to term FM, preterm FM are stronger but have similar heterogeneous weak and strong areas. Following a gradual increase in FM weakness with increasing gestation, there is a major drop-off at term 38 weeks gestation. The FM weak areas are thinner than the stronger areas. Whether the difference in thickness is enough to account for the strength differences is unknown.


Subject(s)
Extraembryonic Membranes/physiology , Fetal Membranes, Premature Rupture/physiopathology , Adolescent , Adult , Biomechanical Phenomena/physiology , Chorioamnionitis/physiopathology , Extraembryonic Membranes/anatomy & histology , Female , Gestational Age , Humans , Labor, Obstetric/physiology , Pregnancy , Young Adult
8.
Placenta ; 32(3): 206-13, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21300402

ABSTRACT

Abruption-induced thrombin generation and inflammation/infection induced cytokine production have both been associated with fetal membrane (FM) weakening and preterm premature rupture of the fetal membranes (PPROM). Using our in vitro model system we have demonstrated that thrombin, and separately the cytokines, tumor necrosis factor-alpha (TNFα) and interleukin-1-beta (IL-1ß), remodel and weaken full thickness FM. Additionally, we have reported that the anti-oxidant and NFκB inhibitor, alpha-lipoic acid (LA), blocks these thrombin and cytokine induced effects. The purpose of these studies was to determine whether thrombin and cytokines directly weaken the amnion membrane (AM), the major load-bearing component of FM. Isolated AM or full thickness FM fragments from unlabored Cesarean deliveries were incubated with thrombin, TNFα, or IL-1ß, for 48 h. Rupture strength (breaking force) of each fragment was thereafter determined using our published methodology. Biochemical evidence of remodeling and apoptosis; immunoreactive Matrix Metalloproteinase 9 (MMP9), Tissue Inhibitor of Matrix Metalloproteinase 3 (TIMP3) and cleaved poly (ADP-ribose) polymerase (C-PARP) levels in tissue extracts, were determined by western blot and densitometry. Thrombin induced a dose-dependent weakening of isolated AM (P < 0.001) coupled with dose dependent increases in PARP cleavage, and reciprocal increases and decreases, respectively, in MMP9 and TIMP3 protein (all P < 0.01). Thrombin receptor activating peptide-6 (TRAP) also weakened isolated AM. Neither TNFα nor IL-1ß weakened isolated AM. However, both cytokines weakened AM when it was incubated together with the choriodecidua as part of full thickness FM (P < 0.001). Cytokine-conditioned choriodecidua medium also weakened isolated AM (P < 0.001). Under conditions in which cytokines weakened the AM, the changes in MMP9, TIMP3 and PARP cleavage were consistent with those seen after thrombin incubation. LA blocked the FM weakening and remodeling effects. In summary, thrombin weakens AM directly whereas cytokines weaken AM indirectly by causing the release of soluble intermediates from the choriodecidua.


Subject(s)
Amnion/physiopathology , Fetal Membranes, Premature Rupture/physiopathology , Interleukin-1beta/physiology , Thrombin/physiology , Tumor Necrosis Factor-alpha/physiology , Acid Phosphatase/pharmacology , Apoptosis/physiology , Biomechanical Phenomena/physiology , Blotting, Western , Densitometry , Female , Humans , In Vitro Techniques , Isoenzymes/pharmacology , Matrix Metalloproteinase 9/physiology , Membrane Glycoproteins/physiology , Pregnancy , Protozoan Proteins/physiology , Tartrate-Resistant Acid Phosphatase , Thioctic Acid/pharmacology , Tissue Inhibitor of Metalloproteinase-3/physiology
9.
Intern Med J ; 41(1a): 27-34, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20492003

ABSTRACT

BACKGROUND/AIM: Numbers of unrelated donor allogeneic haemopoietic cell transplants (HCT) for acute myeloid leukaemia have increased in Australia in recent years. The aims of this study were to investigate the components of this change and find contributing factors to changes in outcome. METHODS: The study method was a retrospective analysis of 213 consecutive first unrelated donor HCT for acute myeloid leukaemia performed within Australia for adult patients during the years of 1992-1997 (n= 43) and 1998-2005 (n= 170). RESULTS: The proportion of patients transplanted in first or second complete remission (CR) increased markedly from 21% in 1992-1997 to 52% in 1998-2005. The cumulative incidence of relapse at 1 year post HCT was significantly lower for the later cohort (22% vs 30%, P= 0.04) and for patients transplanted in CR compared with those not in CR (16% vs 31%, P= 0.01). The overall survival probability was significantly better at 5 years post HCT for patients transplanted in 1998-2005 compared with 1992-1997 (40% vs 21%, P= 0.04). Multivariate analysis identified five independent significant favourable factors for survival among the whole patient group: age under 40 years, transplant in CR1, CR2 or first relapse, patient CMV seronegativity, good performance status and year of transplant within 1998-2005. CONCLUSION: The later cohort of patients had improved survival even after allowing for the effects of age, remission status and other factors, which suggests a general improvement in the safety of the procedure over time, particularly for patients in early disease stages at transplant.


Subject(s)
Hematopoietic Stem Cell Transplantation/statistics & numerical data , Leukemia, Myeloid, Acute/surgery , Living Donors , Adolescent , Adult , Aged , Australia , Cause of Death , Comorbidity , Cytomegalovirus Infections/epidemiology , Female , Humans , Kaplan-Meier Estimate , Leukemia, Myeloid, Acute/epidemiology , Male , Middle Aged , Recurrence , Registries , Remission Induction , Retrospective Studies , Risk Factors , Transplantation, Homologous , Treatment Outcome , Young Adult
10.
Placenta ; 31(10): 886-92, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20709392

ABSTRACT

Cytokine-mediated inflammation and abruption-induced thrombin generation are separately implicated in matrix metalloproteinase (MMP)-mediated weakening of fetal membranes (FM) leading to preterm premature rupture of the fetal membranes (PPROM). At term, FM of both labored vaginal and unlabored Cesarean deliveries exhibit a weak zone overlying the cervix exhibiting ECM remodeling characterized by increased MMP9 protein and activity. We have reproduced these biochemical changes as well as FM weakening in vitro using tumor necrosis factor-alpha (TNF) and interleukin (IL)-1ß, inflammatory cytokines implicated in PPROM. Additionally, we have reported that the antioxidant and NFκB inhibitor alpha-lipoic Acid (LA) blocks these TNF-induced effects. We now present the first direct evidence that thrombin also can induce FM weakening in vitro, and LA treatment inhibits this thrombin-induced-weakening. Full thickness FM fragments from unlabored Cesarean deliveries were incubated with increasing doses of thrombin (0-100 u/ml) for 48 h. Fragments were then strength tested (breaking force and work to rupture) using our published methodology. MMP3 and 9 levels in tissue extracts were determined by Western blot and densitometry. To determine the effect of LA, FM fragments were incubated with control medium or 10 u/ml thrombin, with or without 0.25 mM LA. Strength testing and MMP induction were determined. Thrombin induced a dose-dependent decrease in FM strength (42% baseline rupture force and 45% work to rupture) coupled with a dose-dependent increase in MMP3 and 9 expression (all p < 0.001). Treatment of FM with 0.25 mM LA completely inhibited thrombin-induced FM weakening and MMP expression (all p < 0.001). Thrombin treatment of cultured FM induces mechanical weakening and increased MMP3 and 9. Treatment of FM with LA inhibits these thrombin-induced effects. We speculate LA may prove clinically useful in prevention of PPROM associated with abruption.


Subject(s)
Extraembryonic Membranes/drug effects , Fetal Membranes, Premature Rupture/metabolism , Thioctic Acid/pharmacology , Thrombin/antagonists & inhibitors , Blotting, Western , Dose-Response Relationship, Drug , Extraembryonic Membranes/enzymology , Extraembryonic Membranes/pathology , Female , Humans , Matrix Metalloproteinase 3/metabolism , Matrix Metalloproteinase 9/metabolism , Pregnancy , Thrombin/pharmacology , Thrombin/physiology , Tissue Culture Techniques
11.
Placenta ; 31(1): 18-24, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19922998

ABSTRACT

INTRODUCTION: The fetal membrane (FM) layers, amnion and choriodecidua, are frequently noted to have varying degrees of separation following delivery. FM layers normally separate prior to rupture during in vitro biomechanical testing. We hypothesized that the adherence between amnion and choriodecidua decreases prior to delivery resulting in separation of the FM layers and facilitating FM rupture. METHODS: FM from 232 consecutively delivered patients were examined to determine the extent of spontaneous separation of the FM layers at delivery. Percent separation was determined by the weight of separated FM tissue divided by the total FM weight. Separately, the adherence between intact FM layers was determined. FM adherence was tested following term vaginal delivery (13), term unlabored cesarean section (10), and preterm delivery (6). RESULTS: Subjects enrolled in the two studies had similar demographic and clinical characteristics. FM separation was present in 92.1% of membranes. Only 4.3% of FM delivered following spontaneous rupture of the fetal membranes (SROM) had no detectable separation. 64.7% of FM had greater than 10% separation. FM from term vaginal deliveries had significantly more separation and were less adherent than FM of term unlabored, elective cesarean section (39.0+/-34.4% vs 22.5+/-30.9%, p=.046 and 0.041+/-0.018N/cm vs 0.048+/-0.019N/cm, p<.005). Preterm FM had less separation and were more adherent than term FM (9.95+/-17.7% vs 37.5+/-34.4% and 0.070+/-0.040N/cm vs 0.044+/-0.020N/cm; both p<.001). CONCLUSIONS: Separation of the amnion from choriodecidua at delivery is almost universal. Increased separation is associated with decreased adherence as measured in vitro. Increased separation and decreased adherence are seen both with increasing gestation and with labor suggesting both biochemical and mechanical etiologies. The data are consistent with the hypothesis that FM layer separation is part of the FM weakening process during normal parturition.


Subject(s)
Amnion/physiology , Decidua/physiology , Extraembryonic Membranes/physiology , Labor, Obstetric/physiology , Adhesiveness , Adolescent , Adult , Biomechanical Phenomena , Cell Adhesion/physiology , Extraembryonic Membranes/pathology , Female , Fetal Membranes, Premature Rupture/pathology , Fetal Membranes, Premature Rupture/physiopathology , Gestational Age , Humans , Parturition/physiology , Pregnancy , Young Adult
12.
Placenta ; 30(6): 560-3, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19410292

ABSTRACT

We have previously shown that separation of the amnion from choriodecidua occurs as an integral part of the fetal membranes (FM) rupture process. We have also reported that spontaneous separation of FM is nearly universal with term vaginal delivery. The etiology of this spontaneous FM separation is unknown. If biochemical degradation at the amnion-choriodecidua interface is a factor, decreased adhesive force between the FM components prior to their complete separation would be expected. The purpose of this project was to develop and validate machinery and procedures to measure the adhesive force between amnion and choriodecidua. Commercial tensile testing equipment was adapted to perform a standard T-peel test, per the American Society for Testing and Materials (ASTM) guidelines. FM test strip dimensions, peel speed, and peel force data measurements from force versus displacement curves were optimized for reproducibility. Test system validation was performed using Shurtape CP 60 (slow release painter's masking tape) as the standard. Equipment and procedures for a standard T-peel test on FM were developed. Shurtape CP 60 of decreasing widths showed reproducible, linear changes in the adhesive force range for FM (r(2)=0.96). The adhesive force between FM components ranged from 0.017 to 0.262 N/cm. Reproducibility was optimal with FM test strips of 4 x 6 cm and a peel speed of 25.4 cm/min. FM showed greater adhesive force adjacent to the placental disc than distal from the disc (p<0.05). We have developed equipment and procedures to accurately and reproducibly measure adhesive force between the FM amnion and choriodecidua.


Subject(s)
Amnion/physiology , Chorion/physiology , Decidua/physiology , Extraembryonic Membranes/physiology , Tensile Strength/physiology , Adhesiveness , Amnion/pathology , Biomechanical Phenomena/physiology , Calibration , Chorion/pathology , Decidua/pathology , Diagnostic Techniques, Obstetrical and Gynecological/instrumentation , Extraembryonic Membranes/pathology , Female , Fetal Membranes, Premature Rupture/diagnosis , Fetal Membranes, Premature Rupture/pathology , Fetal Membranes, Premature Rupture/physiopathology , Humans , Pregnancy , Shear Strength/physiology
13.
Placenta ; 30(4): 335-41, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19230968

ABSTRACT

OBJECTIVE: Human fetal membranes (FM) at term have been shown to contain a weak zone in the region overlying the cervix which exhibits characteristics of increased collagen remodeling and apoptosis. It has been hypothesized that the FM rupture initiation site is within this weak zone. Although the FM weak zone has been partially characterized, it is unclear what structural differences in the extracellular matrix result in its decreased rupture strength. A screen for differentially expressed proteins in the amnion of the weak zone versus other FM areas demonstrated that fibulin 1 was decreased. We investigated potential regional differences in all fibulin protein family members. METHODS: FM fibulins were localized by immunohistochemistry. Detected fibulins were screened by Western blot for differences in abundance in the amnion of the weak zone versus non-weak zone FM regions. Amnion epithelial and mesenchymal cells were also screened for fibulin production. RESULTS: Fibulins 1 and 5 were detected in the cytoplasm of and in a pericellular pattern surrounding all FM cells, and in a dense extracellular pattern in the amniotic compact zone. Fibulin 3 was detected within the cytoplasm of amnion epithelial and chorion trophoblast cells. Fibulins 2 and 4 were not detected. Fibulins 1, 3 and 5 demonstrated decreased abundance of 33%, 63% and 58% (all P<0.01) in amnion of the weak zone relative to other FM regions. Amnion cells produced all three detected fibulins. Furthermore, TNF inhibited amnion cell fibulin production in a dose dependent manner. CONCLUSION: Fibulins 1, 3 and 5 were localized coincident with major microfibrillar networks in amnion. Each showed decreased abundance in the amnion component of the FM weak zone. Amnion epithelial and mesenchymal cells produced all three fibulins and their abundance was inhibited by TNF. We speculate that the amnion microfibrillar layer undergoes significant remodeling with the development of the FM weak zone.


Subject(s)
Calcium-Binding Proteins/metabolism , Extraembryonic Membranes/metabolism , Amnion/cytology , Amnion/metabolism , Biomechanical Phenomena , Blotting, Western , Cells, Cultured , Cervix Uteri/anatomy & histology , Cervix Uteri/physiology , Down-Regulation , Extracellular Matrix Proteins/metabolism , Extraembryonic Membranes/anatomy & histology , Extraembryonic Membranes/physiology , Female , Humans , Immunohistochemistry , In Vitro Techniques , Pregnancy , Protein Array Analysis , Proteome , Tissue Distribution
14.
Placenta ; 27(11-12): 1037-51, 2006.
Article in English | MEDLINE | ID: mdl-16516962

ABSTRACT

Premature rupture of the fetal membranes is a major cause of preterm birth and its associated infant morbidity and mortality. Recently, it has become clear that rupture of the fetal membranes, term or preterm, is not merely the result of the stretch and shear forces of uterine contractions, but is, in significant part, the consequence of a programmed weakening process. Work in the rat model has demonstrated that collagen remodeling, with activation of matrix metalloproteinases (MMPs), and apoptosis increase markedly in the amnion at end-gestation, suggesting that these processes are involved in fetal membrane weakening. We have developed fetal membrane strength testing equipment and a systematic tissue sampling methodology that has allowed us to demonstrate that term, non-labored, fetal membranes have a zone of weakness overlying the cervix, which contains biochemical markers of both collagen remodeling and apoptosis. These findings provide strong support for the concept of programmed fetal membrane weakening prior to labor. Our model has also been used to establish the physical properties of individual fetal membrane components (amnion, chorion), determine the sequence of events during the fetal membrane rupture process, and demonstrate that treatment of fetal membranes with TNF or IL-1beta, in vitro, induces weakness and the identical biochemical markers of collagen remodeling and apoptosis seen in the physiological weak zone. The ability to simultaneously correlate macroscopic physical properties with histological and biochemical fetal membrane characteristics, presents a unique perspective on the physiology of fetal membrane rupture.


Subject(s)
Extraembryonic Membranes/physiology , Fetal Membranes, Premature Rupture/physiopathology , Labor, Obstetric/physiology , Amnion/physiopathology , Animals , Apoptosis/physiology , Biophysical Phenomena , Biophysics , Chorion/physiopathology , Cytokines/physiology , Decidua/physiopathology , Female , Humans , Matrix Metalloproteinases/metabolism , Pregnancy , Prostaglandins/physiology , Tensile Strength
15.
Biol Reprod ; 72(3): 720-6, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15548732

ABSTRACT

The etiology of fetal membrane (FM) rupture is unknown. A hypothesis that the FM weakens by a process of collagen remodeling and apoptosis to facilitate rupture has been proposed. Human FMs reportedly exhibit a zone of altered histology, postulated to be the FM rupture site, but concomitant FM weakness has not been demonstrated. We hypothesized that a discrete zone of FM with marked weakness, histological change, and evidence of remodeling and apoptosis, develops in late gestation in the FM overlying the cervix. FM tissue from women undergoing prelabor cesarean delivery were perioperatively marked to identify the FM overlying the cervix, cut with a procedure that facilitates remapping the rupture strength of FM pieces to their former location and orientation on a three-dimensional model, and tested for strength. A 10-cm FM zone centered at the cervical mark was compared with the remaining FM. Mean rupture strength within the cervical zone was 55% of the remaining FM. The cervical zone also exhibited increased MMP-9 protein, decreased tissue inhibitor of metalloproteinases-3 (TIMP-3) protein, and increased PARP cleavage coincident with the previously reported zone of altered histology. A discrete zone of weakness is present in term prelabor FMs overlying the cervix and has biochemical characteristics consistent with tissue remodeling and apoptosis.


Subject(s)
Cervix Uteri/metabolism , Extraembryonic Membranes/metabolism , Labor Onset/physiology , Rupture, Spontaneous/metabolism , Apoptosis/physiology , Collagen/metabolism , Extraembryonic Membranes/cytology , Female , Humans , Matrix Metalloproteinase 9/metabolism , Placenta/metabolism , Pregnancy , Reference Values , Tensile Strength/physiology , Tissue Distribution , Tissue Inhibitor of Metalloproteinase-3/metabolism , Uterus/metabolism
16.
Best Pract Res Clin Haematol ; 17(2): 263-76, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15302339

ABSTRACT

Haematopoietic stem cell transplantation (HSCT) is now being investigated as a potential therapy for patients with severe refractory rheumatoid arthritis unresponsive to conventional therapies, including tumour necrosis factor-alpha blockade. Pilot studies and an analysis of worldwide cases included in the European Group for Blood and Marrow Transplantation/Autologous Blood and Marrow Transplant Registry registry have enabled the progression of the technique. HSCT is well tolerated in patients with rheumatoid arthritis, and there has been no transplant-related mortality. Although HSCT is not a cure, an improved response to previously ineffective therapies is often seen. Further research is, however, required, and this procedure is still considered appropriate only for those patients for whom there is no reasonable therapeutic alternative. This paper reviews all the previous data relating to HSCT in rheumatoid arthritis, outlines the current stand and discusses future protocol options and research.


Subject(s)
Arthritis, Rheumatoid/therapy , Stem Cell Transplantation , Hematopoietic Stem Cells/pathology , Humans , Transplantation, Autologous , Treatment Outcome
17.
Placenta ; 25(6): 573-9, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15135241

ABSTRACT

This study was undertaken to investigate the effect of hydrogen peroxide (HP), a reactive oxygen species, and vitamin C, an antioxidant, on apoptosis and prostaglandin (PGE(2)) release in human amnion epithelial and mesenchymal cells, and intact amnion. Amnion cells and explants were incubated with and without HP and vitamin C. Cytoproliferation assay for viability, DNA fragmentation and PARP cleavage for apoptosis, EIA for PGE(2), and western blots for cyclooxygenases (COX) were performed. In amnion cells and explants, HP (0-5 mm) induced dose dependent apoptosis as per DNA fragmentation and PARP cleavage. HP (0-0.5 mm) also induced PGE(2)release concomitant with apoptosis in both cell types. In amnion explants, HP (0-10 mm) induced COX-2 protein and PGE(2)release concomitant with apoptosis. Vitamin C (0.01-10 mm), alone, enhanced epithelial but inhibited mesenchymal cell viability. It induced PGE(2)release in amnion explants. Vitamin C (1 mm) failed to inhibit HP induced apoptosis, but instead exacerbated it in epithelial and mesenchymal cells, and amnion explants. Vitamin C (0-10 mm) enhanced HP induced PGE(2)in mesenchymal cells. HP induces concomitant apoptosis and PGE(2)release in amnion epithelial and mesenchymal cells, and in intact amnion explants. HP induced apoptosis is not inhibited but enhanced by vitamin C.


Subject(s)
Amnion/drug effects , Apoptosis/drug effects , Ascorbic Acid/pharmacology , Dinoprostone/metabolism , Hydrogen Peroxide/pharmacology , Amnion/cytology , Amnion/physiology , Cells, Cultured , Cyclooxygenase 2 , DNA Fragmentation , Epithelial Cells/cytology , Epithelial Cells/drug effects , Epithelial Cells/physiology , Female , Humans , Isoenzymes/metabolism , Membrane Proteins , Mesoderm/cytology , Mesoderm/drug effects , Mesoderm/physiology , Pregnancy , Prostaglandin-Endoperoxide Synthases/metabolism , Tissue Culture Techniques
18.
Placenta ; 25(4): 266-72, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15028418

ABSTRACT

Increased reactive oxygen species (ROS) have been identified as a potential cause of remodelling and apoptotic change in fetal membrane. Vitamin C has been suggested as a therapeutic agent to prevent ROS induced chorio-amnion apoptosis. The purpose of this study was to determine whether hydrogen peroxide (HP), a ROS, initiates apoptosis in the WISH cell model and whether vitamin C would inhibit HP induced apoptosis. HP induced apoptosis in WISH cells; as assessed by cytochrome-c release from mitochondria, Poly-(ADP-ribose)-Polymerase (PARP) cleavage, nuclear matrix protein (NMP) release and DNA fragmentation analysis. HP induced dose dependent release of cytochrome-c, PARP cleavage, NMP release, and DNA fragmentation. HP also increased PGE(2)release in parallel with apoptosis in WISH cells, in a manner similar to that reported with other apoptotic agents. Vitamin C pre-incubation caused cytochrome-c release earlier, and at lower HP doses, than HP alone. It had no effect on HP induced PARP cleavage, but enhanced DNA fragmentation, and induced NMP release on its own. Vitamin C partially suppressed dose dependent HP induced PGE(2)release. We conclude that HP causes apoptosis in WISH cells and vitamin C pre-incubation does not inhibit, and may accelerate and exacerbate, HP induced apoptosis.


Subject(s)
Amnion/drug effects , Antioxidants/pharmacology , Apoptosis/drug effects , Ascorbic Acid/pharmacology , Hydrogen Peroxide/pharmacology , Amnion/metabolism , Amnion/pathology , Blotting, Western , Cells, Cultured , Cytochromes c/metabolism , DNA Fragmentation , Dinoprostone/metabolism , Dose-Response Relationship, Drug , Drug Interactions , Mitochondria/drug effects , Mitochondria/enzymology , Nuclear Matrix-Associated Proteins/metabolism , Poly(ADP-ribose) Polymerases/metabolism
19.
Bone Marrow Transplant ; 32 Suppl 1: S53-6, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12931243

ABSTRACT

The substantial morbidity and mortality associated with rheumatoid arthritis (RA), while not widely appreciated, provide adequate justification for consideration of high-dose immunoablative therapy followed by hematopoietic stem cell transplantation. While some patients with RA follow a benign course, selected subsets of patients have been identified with 5-year survival rates of 40-70%. A number of factors that can be easily determined serve as useful prognostic indicators for poor outcome. These include the presence of many involved joints (total joint count), the degree of functional disability as measured by the health assessment questionnaire and the presence of rheumatoid factor. This article summarises the present status of hematopoietic stem cell transplantation for rheumatoid arthritis and proposes future directions for research.


Subject(s)
Arthritis, Rheumatoid/therapy , Hematopoietic Stem Cell Transplantation/methods , Hematopoietic Stem Cell Mobilization/methods , Humans , Prognosis , Transplantation Conditioning/methods , Treatment Outcome
20.
Placenta ; 24(2-3): 173-80, 2003.
Article in English | MEDLINE | ID: mdl-12566244

ABSTRACT

Foetal membrane rupture is thought to follow from gene-controlled tissue remodelling and apoptosis. We reported previously that staurosporine, cycloheximide, actinomycin D, as well as more physiological apoptotic agents (lactosylceramide, 15d-PGJ(2)) increase prostaglandin release in parallel with induction of apoptosis in WISH and amnion epithelial cells. Also, inhibition of prostaglandin release by cyclooxygenase inhibitors or PKA activators is accompanied by a parallel decrease in apoptosis. We hypothesize that amnion prostaglandin metabolism is linked with apoptosis in amnion epithelial cells and thus to membrane rupture. Amnion mesenchymal cells are also critical for membrane integrity. Their susceptibility to apoptotic agents is unknown and is the subject of this report. In amnion epithelial cells, lactosylceramide (125 microM) induced 6.5-fold, 20-fold increases in PGE(2) and NMP production (apoptosis), respectively. Conversely, in mesenchymal cells, lactosylceramide doses up to 200 microM had no effect on PGE(2) or NMP release. In both cell types, incubation with 15d-PGJ(2) (5-100 microM) demonstrated dose and time dependent increases in PGE(2) and NMP. PKA activators inhibited 15d-PGJ(2) induced PGE(2) release and apoptotis in epithelial cells, but not in mesenchymal cells, however. Major amnion cell types have different sensitivities to physiological apoptotic agents. Prostaglandin release occurs coincident with apoptosis in both amnion epithelial and mesenchymal cells.


Subject(s)
Amnion/drug effects , Apoptosis/drug effects , Immunologic Factors/pharmacology , Lactosylceramides/pharmacology , Prostaglandin D2/pharmacology , 8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Adult , Amnion/metabolism , Amnion/pathology , Cell Line , Cyclooxygenase Inhibitors/pharmacology , DNA Fragmentation/drug effects , Dinoprostone/metabolism , Dose-Response Relationship, Drug , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/pathology , Female , Humans , Mesoderm/drug effects , Mesoderm/metabolism , Mesoderm/pathology , Nitrobenzenes/pharmacology , Pregnancy , Prostaglandin D2/analogs & derivatives , Pyrazoles/pharmacology , Sulfonamides/pharmacology
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