Histological Features of Uterine Myometrial Dysfunction: Possible Involvement of Localized Inflammation

OBJECTIVE

The latest perspective suggests that elevated levels of inflammation and cytokines are implicated in atonic postpartum hemorrhage. Lipopolysaccharide (LPS) has been widely used to induce inflammation in animal models. Therefore, this study aimed to induce uterine inflammation using LPS to investigate whether local inflammation triggers dysfunction and atrophy in the myometrium, as well as the potential underlying molecular mechanisms involved.

METHODS

In vivo, an animal model was established by intraperitoneal injection of 300 μg/ kg LPS in rats on gestational day 21. Hematoxylin-eosin (H&E) staining and Masson staining were employed to determine morphological changes in the rat uterine smooth muscle. Enzyme-linked immunosorbent assay (ELISA) was used to detect inflammatory cytokines. Immunohistochemistry, tissue fluorescence, and Western blotting were conducted to assess the expression levels of the uterine contraction-related proteins Toll-like receptor 4 (TLR4) and the nuclear factor kappa-B (NF-κB) signaling pathway. In vitro, human uterine smooth muscle cells (HUtSMCs) were exposed to 2 μg/mL LPS to further elucidate the involvement of the TLR4/NF-κB signaling pathway in LPS-mediated inflammation.

RESULTS

In this study, LPS induced uterine myometrial dysfunction in rats, leading to a disorganized arrangement, a significant increase in collagen fiber deposition, and widespread infiltration of inflammatory cells. In both in vivo animal models and in vitro HUtSMCs, LPS elevated IL-6, IL-1β, and TNF-α levels while concurrently suppressing the expression of connexin 43 (Cx43) and oxytocin receptor (OXTR). Mechanistically, the LPS-treated group exhibited TLR4 activation, and the phosphorylation levels of p65 and IκBα were notably increased.

CONCLUSION

LPS triggered the TLR4/NF-κB signaling pathway, inducing an inflammatory response in the myometrium and leading to uterine myometrial dysfunction and uterine atony.

Effect of Third Interstitial Fluid on Adverse Outcomes in Patients with Severe Pre-eclampsia and Twin Pregnancy: A 5-year Single-center Retrospective Study

OBJECTIVE

This study aims to identify the effect of third interstitial fluid on adverse outcomes in twin pregnancies with severe pre-eclampsia, and explore the differences in bad ending between twins and singletons.

METHODS

The present retrospective cohort study was conducted on patients with severe pre-eclampsia, who delivered in Tongji Hospital, Wuhan, China, between 2017 and 2022. The adverse outcomes in singleton and twin pregnancies with severe pre-eclampsia were initially investigated. Then, the diverse maternal and fetal consequences between singleton and twin pregnancies in patients with severe pre-eclampsia were compared after merging with the third interstitial fluid.

RESULTS

A total of 709 patients were included for the present study. Among these patients, 68 patients had twin pregnancies, and 641 patients had singleton pregnancies. The rate of postpartum hemorrhage (2.81% vs. 13.24%, P<0.001), and admission rate to the Neonatal Intensive Care Unit (NICU) after birth (30.73% vs. 63.24%, P=0.011) were significantly higher in twin pregnancies. The neonatal weight of twins was statistically lower than singletons (1964.73±510.61 g vs. 2142.92±731.25 g, P=0.008). For the groups with the third interstitial fluid, the delivery week (P=0.001) and rate of admission to the NICU after birth were significantly advanced in twin pregnancy group, when compared to singleton pregnancy group (P=0.032), and the length of hospital stay was shorter (P=0.044). Furthermore, there was no statistically significant difference between the twin pregnancy group and the singletony pregnancy group without the third interstitial fluid.

CONCLUSION

The maternal and fetal adverse outcomes of patients with severe pre-eclampsia increased in twin pregnancies, when compared to singleton pregnancies. Thus, when patients develop the third interstitial fluid, twin pregnancies would more likely lead to adverse fetal outcomes, when compared to singleton pregnancies, and there would be no significant difference in maternal adverse outcomes. More attention should be given to patients who merge with the third interstitial fluid.

[Expression and diagnostic value of macrophage inflammatory protein-3α in patients with hepatitis B-related acute-on-chronic liver failure]

Objective: To screen serum protein markers and evaluate their diagnostic application value in hepatitis B-related acute-on-chronic liver failure (HBV-ACLF). Methods: Serum samples of patients with HBV-ACLF, chronic hepatitis B (CHB) and normal healthy volunteers (n = 5/group) were determined by cytokine antibody chip in line with the Chinese Diagnostic Standards Study for HBV-ACLF (COSSH-ACLF) cohort. The differentially expressed proteins significance were identified by microarray analysis and prediction. The preliminary serological markers of HBV-ACLF were screened for diagnosis. The potential markers were determined by enzyme-linked immunosorbent assay (ELISA), area under the receiver operating characteristic curve (AUROC) analysis and liver tissue immunohistochemistry for the diagnosis of HBV-ACLF. Student t-test or Mann-Whitney U test were used to compare the continuous measurement data between the two groups, and analysis of variance and Kruskal-Wallis test were used to compare the continuous measurement data between multiple groups. Results: Cytokine antibody chip preliminary screening results showed that the expression levels of these six cytokines, namely, macrophage inflammatory protein 3α (MIP-3α), hepatocyte growth factor, E-selectin, osteopontin, growth differentiation factor 15 and carcinoembryonic antigen-related cellular adhesion molecule 1 were significantly increased in the HBV-ACLF group. Among them, the expression level of MIP-3α was significantly higher in the HBV-ACLF group (99.6 times higher than CHB group and 146.9 times higher than healthy volunteers' group, respectively, P < 0.0001) as validated by serum ELISA in 132 HBV-ACLF cases, 91 CHB cases and 72 healthy volunteers. AUROC analysis showed that the high expression of MIP-3α could be used as a marker to distinguish patients with HBV-ACLF from CHB. The AUROC was 0.995 (95% CI: 0.990 ~ 1.000), with sensitivity and specificity of 95.5% and. 98.9%, respectively. Immunohistochemistry showed that MIP-3α was positively expressed in HBV-ACLF-derived liver tissues, and negatively expressed in CHB-derived liver and normal liver tissues. Conclusion: Serum MIP-3α level is closely related to the pathological characteristics of HBV-ACLF. Therefore, it may be used as a potential serological marker for the diagnosis of HBV-ACLF.

CLDN1 expression in cervical cancer cells is related to tumor invasion and metastasis

Even though infection with human papillomaviruses (HPV) is very important, it is not the sole cause of cervical cancer. Because it is known that genetic variations that result from HPV infection are probably the most important causes of cervical cancer, we used human whole genome array comparative genomic hybridization to detect the copy number variations of genes in cervical squamous cell carcinoma. The results of the array were validated by PCR, FISH and immunohistochemistry. We find that the copy number and protein expression of claudin-1 (CLDN1) increase with the progression of cervical cancer. The strong positive staining of CLDN1 in the cervical lymph node metastasis group received a significantly higher score than the staining in the group with no lymph node metastasis of cervical cancer tissues. The overexpression of CLDN1 in SiHa cells can increase anti-apoptosis ability and promote invasive ability of these cells accompanied by a decrease in expression of the epithelial marker E-cadherin as well as an increase in the expression of the mesenchymal marker vimentin. CLDN1 induces the epithelial-mesenchymal transition (EMT) through its interaction with SNAI1. Furthermore, we demonstrate that CLDN1 overexpression has significant effects on the growth and metastasis of xenografted tumors in athymic mice. These data suggest that CLDN1 promotes invasion and metastasis in cervical cancer cells via the expression of EMT/invasion-related genes. Therefore, CLDN1 could be a potential therapeutic target for the treatment of cervical cancer.

SIX1 promotes tumor lymphangiogenesis by coordinating TGFβ signals that increase expression of VEGF-C

Lymphatic vessels are one of the major routes for the dissemination of cancer cells. Malignant tumors release growth factors such as VEGF-C to induce lymphangiogenesis, thereby promoting lymph node metastasis. Here, we report that sine oculis homeobox homolog 1 (SIX1), expressed in tumor cells, can promote tumor lymphangiogenesis and lymph node metastasis by coordinating with TGFβ to increase the expression of VEGF-C. Lymphangiogenesis and lymph node metastasis in cervical cancer were closely correlated with higher expression of SIX1 in tumor cells. By enhancing VEGF-C expression in tumor cells, SIX1 could augment the promoting effect of tumor cells on the migration and tube formation of lymphatic endothelial cells (LEC) in vitro and lymphangiogenesis in vivo. SIX1 enhanced TGFβ-induced activation of SMAD2/3 and coordinated with the SMAD pathway to modulate VEGF-C expression. Together, SIX1 and TGFβ induced much higher expression of VEGF-C in tumor cells than each of them alone. Despite its effect in promoting VEGF-C expression, TGFβ could inhibit lymphangiogenesis by directly inhibiting tube formation by LECs. However, the increased production of VEGF-C not only directly promoted migration and tube formation of LECs but also thwarted the inhibitory effect of TGFβ on LECs. That is, tumor cells that expressed high levels of SIX1 could promote lymphangiogenesis and counteract the negative effects of TGFβ on lymphangiogenesis by increasing the expression of VEGF-C. These findings provide new insights into tumor lymphangiogenesis and the various roles of TGFβ signaling in tumor regulation. Our results also suggest that SIX1/TGFβ might be a potential therapeutic target for preventing lymph node metastasis of tumor.

Rapid and sensitive detection of infectious spleen and kidney necrosis virus by loop-mediated isothermal amplification combined with a lateral flow dipstick

Loop-mediated isothermal amplification (LAMP) allows rapid amplification of nucleic acids under isothermal conditions. In this report, a 20-min LAMP amplification of the DPOL gene of infectious spleen and kidney necrosis virus (ISKNV) using a biotin-labeled primer was combined with lateral flow dipstick (LFD) chromatography for rapid and simple visual detection of ISKNV-specific amplicons. The LFD process involves a 5-min specific hybridization with an FITC-labeled DNA probe to confirm the presence of complement ISKNV amplicons that were biotinated in LAMP. The resulting DNA duplexes, consisting of labeled probes and amplicons, migrate along the LFD strip by chromatography for 5 min and are trapped at the test line and visualized by biotin labeling. The detection limit of ISKNV by LAMP-LFD was 10 copies. The results show that the LAMP-LFD method has the advantages of better sensitivity and speed and less dependence on equipment than the standard PCR for specifically detecting low levels of ISKNV DNA, and this can be useful in the field as a routine diagnostic tool.

Structure of human thymidylate synthase suggests advantages of chemotherapy with noncompetitive inhibitors

Thymidylate synthase (TS) is a major target in the chemotherapy of colorectal cancer and some other neoplasms. The emergence of resistance to the treatment is often related to the increased levels of TS in cancer cells, which have been linked to the elimination of TS binding to its own mRNA upon drug binding, a feedback regulatory mechanism, and/or to the increased stability to intracellular degradation of TS.drug complexes (versus unliganded TS). The active site loop of human TS (hTS) has a unique conformation resulted from a rotation by 180 degrees relative to its orientation in bacterial TSs. In this conformation, the enzyme must be inactive, because the catalytic cysteine is no longer positioned in the ligand-binding pocket. The ordered solvent structure obtained from high resolution crystallographic data (2.0 A) suggests that the inactive loop conformation promotes mRNA binding and intracellular degradation of the enzyme. This hypothesis is supported by fluorescence studies, which indicate that in solution both active and inactive forms of hTS are present. The binding of phosphate ion shifts the equilibrium toward the inactive conformation; subsequent dUMP binding reverses the equilibrium toward the active form. Thus, TS inhibition via stabilization of the inactive conformation should lead to less resistance than is observed with presently used drugs, which are analogs of its substrates, dUMP and CH(2)H(4)folate, and bind in the active site, promoting the active conformation. The presence of an extension at the N terminus of native hTS has no significant effect on kinetic properties or crystal structure.