MicroRNA‑155‑5p inhibits trophoblast cell proliferation and invasion by disrupting centrosomal function

Recurrent miscarriage is used to refer to more than three pregnancy failures before 20 weeks of gestation. Defective trophoblast cell growth and invasion are frequently observed in recurrent miscarriage. Several microRNAs (miRs), including miR‑155‑5p, are aberrantly upregulated in recurrent miscarriage; however, the underlying molecular mechanisms remain unclear. The centrosome orchestrates microtubule networks and coordinates cell cycle progression. In addition, it is a base for primary cilia, which are antenna‑like organelles that coordinate signaling during development and growth. Thus, deficiencies in centrosomal functions can lead to several disease, such as breast cancer and microcephaly. In the present study, the signaling cascades were analyzed by western blotting, and the centrosome and primary cilia were observed and analyzed by immunofluorescence staining. The results showed that overexpression of miR‑155‑5p induced centrosome amplification and blocked primary cilia formation in trophoblast cells. Notably, centrosome amplification inhibited trophoblast cell growth by upregulating apoptotic cleaved‑caspase 3 and cleaved‑poly (ADP‑ribose) polymerase in miR‑155‑5p‑overexpressing trophoblast cells. In addition, overexpression of miR‑155‑5p inhibited primary cilia formation, thereby inhibiting epithelial‑mesenchymal transition and trophoblast cell invasion. All phenotypes could be rescued when cells were co‑transfected with the miR‑155‑5p inhibitor, thus supporting the role of miR‑155‑5p in centrosomal functions. It was also found that miR‑155‑5p activated autophagy, whereas disruption of autophagy via the depletion of autophagy‑related 16‑like 1 alleviated miR‑155‑5p‑induced apoptosis and restored trophoblast cell invasion. In conclusion, the present study indicated a novel role of miR‑55‑5p in mediating centrosomal function in recurrent miscarriage.

Rice straw-derived chitosan-enhanced plasticizers as biologically and environmentally friendly alternatives for sustainable materials

Plasticizers like Bis(2-ethylhexyl)phthalate (DEHP) are commonly used to enhance plastic properties but pose environmental and health risks. This study successfully derived plasticizers X and Y from rice straws, demonstrating efficacy in chitosan polymer coatings. Chitosan-based polymers exhibit exceptional hardness, with a value of 300 MPa, due to their enriched structure and robust chitosan bonding. This surpasses the hardness of DEHP. Zebrafish exposure over 5 days revealed that X and Y had no significant behavioral impact, while DEHP caused noticeable toxic effects. Maternal DEHP exposure reduced placental cell growth, unlike X and Y, which had no adverse effects on uterine differentiation or placenta formation, suggesting their safety in human pregnancy. The successful development of X and Y represents a crucial step towards greener plasticizers, addressing environmental concerns and promoting safer alternatives in various industries.

Upregulation of miR-20b-5p inhibits trophoblast invasion by blocking autophagy in recurrent miscarriage

Recurrent miscarriage is defined as more than three pregnancy failures occurring before 20 weeks of gestation. Poor differentiation of the endometrial stroma or defective trophoblast cell invasion at the maternal-fetal interface leads to recurrent miscarriages. Several miRNAs, including miR-20b-5p, are aberrantly regulated in recurrent miscarriages; however, the underlying molecular mechanisms remain unclear. Primary cilia are antenna-like organelles that coordinate signaling during development and differentiation. Defective primary cilia formation leads to complications, such as recurrent miscarriage or preeclampsia. Here, we demonstrated that miR-20b-5p inhibited trophoblast cell invasion by blocking primary cilia formation. Mechanistically, miR-20b-5p targeted and inhibited ATG16L1 and ATG7 expression, thereby blocking autophagy. Defective autophagy reduced primary cilia formation and stopped ERK activation, which is a crucial signaling pathway for trophoblast invasion. Aspirin is used to prevent recurrent miscarriages in clinical settings. Treatment with aspirin inhibited miR-20b-5p levels, thus restoring primary cilia formation and trophoblast invasion. Thus, our findings uncovered the molecular mechanism by which miR-20b-5p suppressed primary cilia formation and trophoblast invasion by reducing the expression of ATG16L1 and ATG7. Moreover, we found that the defective phenotypes could be rescued by aspirin in recurrent miscarriages.

Manipulation of osteogenic and adipogenic differentiation of human degenerative disc and ligamentum flavum derived progenitor cells using IL-1β, IL-19, and IL-20

PURPOSE

To elucidate whether pro-inflammatory cytokines might influence the commitment of intervertebral disc (IVD)- and ligamentum flavum (LF)-derived progenitor cells toward either osteogenesis or adipogenesis, specifically Interleukin-1β (IL-1β), IL-19, and IL-20.

METHODS

Sixty patients with degenerative spondylolisthesis and lumbar or lumbosacral spinal stenosis were included in the study. Injuries to the spine, infections, and benign or malignant tumors were excluded. From nine patient samples, IVD- and LF-derived cells were isolated after primary culture, and two clinical samples were excluded due to mycoplasma infection. The effects of IL-1β, IL-19, as well as IL-20 in regulating osteogenic and adipogenic differentiation in vitro were investigated.

RESULTS

Primary IVD- and LF-derived cells were found to have a similar cell morphology and profile of surface markers (CD44, CD90, and CD105) as placenta-derived mesenchymal stem cells (MSCs). Primary IVD/LF cells have a high capacity to differentiate into osteocytes and adipocytes. IL-19 had a tendency to promote adipogenesis. IL-20 inhibited osteogenesis and promoted adipogenesis; IL-1β promoted osteogenesis but inhibited adipogenesis.

CONCLUSION

IL-1β, IL-19, and IL-20 impact the adipogenic and osteogenic differentiation of IVD-derived and LF-derived cells. Modulating the expression of IL-1β, IL-19, and IL-20 provides a potential avenue for controlling cell differentiation of IVD- and LF-derived cells, which might have beneficial effect for degenerative spondylolisthesis and spinal stenosis.

Aspirin facilitates trophoblast invasion and epithelial-mesenchymal transition by regulating the miR-200-ZEB1 axis in preeclampsia

Preeclampsia is a severe gestational hypertensive disorder that occurs after 20 weeks' of gestation. It involves several maternal systems, such as cardiovascular, renal, coagulatory systems, and poses a major threat to the maternal and fetal health. Recent clinical evidence showed that aspirin is an effective preventative treatment for reducing the incidence of premature preeclampsia among high-risk pregnant women, however, the mechanism of drug action is not clear. miR-200 family has been shown to be associated with preeclampsia and upregulated in the plasma and placenta of preeclamptic patients. Here we revealed that miR-200 family inhibited trophoblast invasion and epithelial-mesenchymal transition (EMT) process by stimulating epithelial marker expression (E-cadherin and ZO-1) and repressing mesenchymal marker expression (ZEB1 and TGFβ1). Similarly, EMT markers in the placenta of preeclamptic patients showed higher E-cadherin and lower ZEB1 and TGF-β1 protein expression. Moreover, aspirin was shown to suppress miR-200 family and these miR-200 family-mediated cell functions, including cell invasion and EMT changes, were completely reversed. In conclusion, this study demonstrates the effect of miR-200 family on trophoblast invasion and EMT. For the first time, aspirin was shown to fully reverse miR-200-mediated trophoblast biology and act through the network signaling of TGF-β1/ZEB1/miR-200. These results provide a plausible mechanism explaining aspirin's effect on preeclampsia prevention and a therapeutic target for disease intervention.

Elevated miR-200a and miR-141 inhibit endocrine gland-derived vascular endothelial growth factor expression and ciliogenesis in preeclampsia

KEY POINTS

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is a critical factor that facilitates trophoblast invasion in placenta. Plasma miR-141 and miR-200a levels were elevated, while EG-VEGF was decreased in peripheral blood and placenta of preeclamptic patients. Furthermore, numbers of cilia in the placenta from preeclamptic women were significantly decreased. Elevated miR-141 and miR-200a inhibited the expression of EG-VEGF, downstream extracellular signal-regulated kinase (ERK)/matrix metalloproteinase 9 signalling and cilia formation, thus leading to defective trophoblast invasion. The growth of the primary cilium, which transduced ERK signalling upon EG-VEGF induction for proper trophoblast invasion, was also inhibited by miR-141 and miR-200a upregulation.

ABSTRACT

Preeclampsia is a severe gestational complication, and inadequate trophoblast invasion during placental development is an important pathoaetiology. Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is a critical factor that facilitates trophoblast invasion in placenta. By binding to the primary cilium, EG-VEGF initiates the signalling cascade for proper embryo implantation and placental development. The miR-200 family was predicted to target the EG-VEGF 5'-untranslated region, and its specific binding site was confirmed using a dual luciferase and a co-transfection assay. In the peripheral blood and placenta of preeclamptic patients, EG-VEGF showed significantly lower expression, whereas plasma miR-141 and miR-200a had higher expression compared with the controls. The biological significance of miR-141 and miR-200a was verified using an overexpression method in a trophoblast cell line (HTR-8/SVneo). Elevated miR-141 and miR-200a inhibited the expression of EG-VEGF, matrix metalloproteinase 9 (MMP9) and downstream extracellular signal-regulated kinase (ERK) signalling, thus leading to defective trophoblast invasion. Additionally, the growth of the primary cilium, which transduces ERK/MMP9 signalling upon EG-VEGF induction, was inhibited by miR-141 and miR-200a upregulation. Furthermore, the number of cilia in the human placenta of preeclamptic women was significantly decreased compared to normal placenta. In conclusion, the study uncovers the clinical correlations among the miR-200 family, EG-VEGF and the primary cilium in preeclampsia and the underlying molecular mechanisms. The results indicate that miR-141 and miR-200a directly targeted EG-VEGF, suppressed primary cilia formation and inhibited trophoblast invasion. Thus, miR-141 and miR-200a could be explored as promising miRNA biomarkers and therapeutic targets in preeclampsia.

The roles of IL-19 and IL-20 in the inflammation of degenerative lumbar spondylolisthesis

Background

Degenerative lumbar spondylolisthesis (DLS) is a major cause of spinal canal stenosis and is often related to lower back pain. IL-20 is emerging as a potent angiogenic, chemotactic, and proinflammatory cytokine related to several chronic inflammatory bone disorders likes intervertebral disc herniation, rheumatoid arthritis (RA), osteoporosis, and bone fracture. IL-19 also acts as a proinflammatory cytokine in RA. The aim of the present study was to investigate whether IL-19 and IL-20 are involved in DLS and compare three different tissues including disc, facet joint, and ligamentum flavum of patients with DLS to verify which tissue is affected more by inflammation.

Methods

Disc, facet joint and ligamentum flavum from 13 patients with DLS was retrieved, and the expression pattern of IL-19, IL-20, IL-20R1, IL-20R2, TNF-α, IL-1β, and MCP-1 was evaluated using immunohistochemical staining with specific antibodies. The disc cells were isolated and incubated with IL-19 and IL-20 under CoCl₂-mimicked hypoxic conditions to analyze the proinflammatory cytokine expression pattern using real-time quantitative PCR with specific primers.

Results

IL-19 and IL-20 were positively stained and accompanied by abundant expression of TNF-α, IL-1β, and MCP-1 in facet joints of DLS patients. IL-19 and IL-20's receptors (IL-20R1 and IL-20R2) were expressed on chondrocytes and fibrocytes/fibroblasts in facet joint and ligamentum flavum tissues from patients with DLS. There was a significant correlation between the expression of IL-20 and IL-1β in facet joint. In vitro assay, IL-19 and IL-20 upregulated the expression of IL-1β, IL-6, TNF-α, IL-8, VEGF, and MCP-1 in primary cultured DLS disc cells under CoCl₂-mimicked hypoxic conditions.

Conclusions

IL-19, IL-20, and their receptors as well as proinflammatory cytokines (TNF-α, IL-1β, and MCP-1) were expressed more in facet joints than the other tissues in patients with DLS; therefore, the etiology of inflammation might be more facet-centric. IL-19 and IL-20 induced proinflammatory cytokine expression in disc cells and might play a role in the pathogenesis of DLS.

miR-346 and miR-582-3p-regulated EG-VEGF expression and trophoblast invasion via matrix metalloproteinases 2 and 9

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an important regulator for embryo implantation and placental development, and is clinically associated with several obstetric disorders related to insufficient or inappropriate trophoblast invasion, such as recurrent abortion, preeclampsia, and intrauterine fetal growth restriction. This study was performed to identify the microRNAs targeting EG-VEGF, and evaluate the regulatory effect on trophoblast biology. miR-346 and miR-582-3p were initially identified via bioinformatic tools, and their specific binding sites on the EG-VEGF 3'UTR were further confirmed using dual luciferase and a co-transfection assays. miR-346 and miR-582-3p were demonstrated not only to suppress EG-VEGF expression, but also inhibit trophoblast invasion and migration in the JAR and HTR-8/SVneo cell lines. We further evaluated the effect of microRNAs in HTR-8/SVneo cells coexpressing EG-VEGF and miR-346 or miR-582-3p on matrix metalloproteinase (MMP 2 and MMP 9) and the tissue inhibitors of metalloproteinase (TIMP 1 and TIMP 2) using RT-PCR, western blotting and gelatin zymography. TIMP 1 and TIMP 2 were not affected by the two microRNAs, whereas the expressions and activities of MMP 2 and MMP 9 were significantly downregulated, which in turn inhibited the invasion ability of trophoblasts. In conclusion, miR-346 and miR-582-3p regulate EG-VEGF-induced trophoblast invasion through repressing MMP 2 and MMP 9, and may become novel diagnostic biomarkers or therapeutic targets for EG-VEGF-related obstetric disorders. © 2016 BioFactors, 43(2):210-219, 2017.

Risk of prostate cancer in African-American men: Evidence of mixed effects of dietary quercetin by serum vitamin D status

BACKGROUND

African-American (AA) men experience higher rates of prostate cancer (PCa) and vitamin D (vitD) deficiency than white men. VitD is promoted for PCa prevention, but there is conflicting data on the association between vitD and PCa. We examined the association between serum vitD and dietary quercetin and their interaction with PCa risk in AA men.

METHODS

Participants included 90 AA men with PCa undergoing treatment at Howard University Hospital (HUH) and 62 controls participating in HUH's free PCa screening program. We measured serum 25-hydroxy vitD [25(OH)D] and used the 98.2 item Block Brief 2000 Food Frequency Questionnaires to measure dietary intake of quercetin and other nutrients. Case and control groups were compared using a two-sample t-test for continuous risk factors and a Fisher exact test for categorical factors. Associations between risk factors and PCa risk were examined via age-adjusted logistic regression models.

RESULTS

Interaction effects of dietary quercetin and serum vitD on PCa status were observed. AA men (age 40-70) with normal levels of serum vitD (>30 ng/ml) had a 71% lower risk of PCa compared to AA men with vitD deficiency (OR = 0.29, 95%CI: 0.08-1.03; P = 0.055). In individuals with vitD deficiency, increased dietary quercetin showed a tendency toward lower risk of PCa (OR = 0.91, 95%CI: 0.82-1.00; P = 0.054, age-adjusted) while men with normal vitD were at elevated risk (OR = 1.23, 95%CI: 1.04-1.45).

CONCLUSION

These findings suggest that AA men who are at a higher risk of PCa may benefit more from vitD intake, and supplementation with dietary quercetin may increase the risk of PCa in AA men with normal vitD levels. Further studies with larger populations are needed to better understand the impact of the interaction between sera vitD levels and supplementation with quercetin on PCa in AA men.

Prospective analysis of KRAS wild-type patients with metastatic colorectal cancer using cetuximab plus FOLFIRI or FOLFOX4 treatment regimens

Cetuximab, a monoclonal antibody targeting epidermal growth factor receptor, has proven to be efficient in the treatment of metastatic colorectal cancer. We made a prospective study of the efficacy and toxicities of cetuximab-combination first-line (FOLFOX4) versus second/third-line (FOLFIRI) chemotherapy in 98 KRAS wild-type patients who had metastatic colorectal cancer. Wild-type KRAS had been identified by direct sequencing. Associations between clinical response/progression-free survival/overall survival/toxicities and cetuximab-combination chemotherapy timing were evaluated. The overall response rate was significantly higher for first-line treatment than for second/third-line treatment (relative risk = 1.707, 95% confidence interval = 1.121-2.598). Both progression-free survival and overall survival indicated significantly longer survival of first-line treatment than second/third-line treatment patients. This study is a validation of a molecular analysis of KRAS wild-type status for the prediction of response to cetuximab-combination chemotherapy for metastatic colorectal cancer patients; its predictive role was less prominent in the second/third-line than in the first-line treatment patients.

Electron microscopy investigations of V defects in multiple InGaN/GaN quantum wells and InGaN quantum dots

The mechanism of high emission of InGaN-based multiple quantum wells, which exhibit exceptionally high light emission efficiency despite their high defect density, is still not fully understood. Here, we deal with this problem, showing the details of structure and formation of V defects in the multiple quantum wells and reviewing interpretations proposed so far. Then, we show a structural investigation of three-dimensional high-density quantum dots, fabricated instead of quantum wells in the active layer. The shape and size of the InGaN quantum dots and the SiN(x) masks for the growth of the dots have been revealed using high-angle annular dark field scanning transmission electron microscopy, energy dispersive X-ray spectroscopy nanoanalysis and high-resolution transmission electron microscopy.

Constructing neural networks for multiclass-discretization based on information entropy

Cios and Liu (1992) proposed an entropy-based method to generate the architecture of neural networks for supervised two-class discretization. For multiclass discretization, the inter-relationship among classes is reduced to a set of binary relationships, and an independent two-class subnetwork is created for each binary relationship. This two-class-based method ends up with the disability of sharing hidden nodes among different classes and a low recognition rate. We keep the interrelationship among classes when training a neural network. Entropy measure is considered in a global sense, not locally in each independent subnetwork. Consequently, our method allows hidden nodes and layers to be shared among classes, and presents higher recognition rates than the two-class-based method.

Prognostic significance of pre- and postoperative serum carcinoembryonic antigen levels in patients with colorectal cancer

BACKGROUND

To evaluate the prognostic significance of pre- and postoperative serum carcinoembryonic antigen(CEA) levels in colorectal cancer (CRC) patients.

METHODS

425 CRC patients underwent curative resection at our institution. Their pre- and postoperative serum CEA level was classified into two groups according to concentration: normal CEA (<5.0 ng/ml) and abnormal CEA (> or =5.0 ng/ml).

RESULTS

Of all patients, abnormal pre- and postoperative serum CEA levels were observed in 181 (42.6%) and 48 (11.3%) patients, respectively. Abnormal preoperative serum CEA level was significantly correlated with the tumor located in the colon, the depth of tumor invasion, the status of lymph node metastasis, UICC stage, and the presence of postoperative relapse (p < 0.05). Concurrently, an abnormal postoperative serum CEA level was also prominently related to the above corresponding parameters (p < 0.05), except for the tumor location. Patients with a failed conversion of abnormal preoperative value to normal postoperative concentration were found to have the worst overall survival rate. Abnormal pre- and postoperative serum CEA levels were single independent predictors for survival and postoperative relapse, respectively.

CONCLUSIONS

The identification of abnormal pre- and postoperative serum CEA levels may be useful in the auxiliary cancer prognosis or postoperative surveillance of CRC patients.

Carbon Monoxide-Induced Early Thrombolysis Contributes to Heme Oxygenase-1-Mediated Inhibition of Neointimal Growth after Vascular Injury in Hypercholesterolemic Mice

Arterial thrombosis is a critical event in the pathogenesis of lesion development. In this study, we evaluated the effect of heme oxygenase-1 (HO-1), a stress-inducible enzyme with vasoprotective functions, on arterial thrombosis following vascular mechanical injury. The carotid arteries of apoE-deficient mice were subjected to angioplasty with a modified beaded-needle. Arterial thrombosis occurred at 12 h after injury. Treatment of the injured vessels with an adenovirus bearing HO-1 gene (Adv-HO-1) (1 x 10(8) pfu), but not saline or empty adenovirus (Adv), immediately after angioplasty resulted in earlier thrombolysis and restoration of blood flow detected at 24 h. Immunohistochemistry revealed that the arterial plasminogen activator inhibitor-1 (PAI-1) expression was markedly reduced in Adv-HO-1-treated injured arteries as compared to control counterparts. The thrombolytic effect was also observed by exposing animals with existing arterial thrombosis to carbon monoxide (CO) (250 ppm, 2 h), a byproduct derived from heme degradation by HO-1. In parallel with less fibrin(ogen) deposition, the macrophage infiltration, monocyte chemoattractant protein-1 expression and neointimal formation assessed at 2 weeks after angioplasty were substantially reduced in injured arteries treated with Adv-HO-1. These results support a role of early thrombolysis induced by CO in HO-1-mediated protection against intimal hyperplasia after vascular injury.

Imaging cells and tissues with refractive index radiology

Can individual cells, including live cells, be imaged using hard x rays? Common wisdom until now required sophisticated staining techniques for this task. We show instead that individual cells and cell details can be detected in culture solution and tissues with no staining and no other contrast-enhancing preparation. The sample examined can be much thicker than for many other microscopy techniques without sacrificing the capability to resolve cells. The key factor in our approach is the use of a coherent synchrotron source and of contrast mechanisms based on the refractive index. The first successful tests were conducted on a variety of cell systems including skin and internal leaf cells, mouse neurons, rabbit fibroblast cells, and human tumor cells.

Dietary iron restriction increases plaque stability in apolipoprotein-e-deficient mice

Accumulative evidence has supported the role of iron in the development of atherosclerosis. To test whether iron-mediated oxidative stress influences plaque stability, apoliporotein-E (ApoE)-deficient mice (3 months old) were placed on a chow diet or a low-iron diet for 3 months, and the abundance of interstitial collagen and the expression of the matrix degradation-associated enzyme, matrix metalloproteinase-9 (MMP-9), in vascular lesions were assessed. A low-iron diet appeared to reduce iron deposition while substantially increasing collagen content of lesions in mice. Immunostaining demonstrated lower expression of MMP-9 in lesions of iron-restricted animals. Likewise, SDS-PAGE zymography revealed lower gelatinolytic activities in aortic tissues and sera of the same group of animals. When older ApoE-deficient mice (5 months old) received a low-iron diet for 2 months, development of the lesion area was not significantly affected. However, the lesional collagen content was much higher in the iron-restricted group of animals, and MMP-9 expression in aortic tissues from the same group of mice was significantly lower. Treatment of murine J774 macrophages with increasing concentrations of ferric ammonium citrate significantly enhanced the amount of MMP-9 secreted. Together, these data indicate that decreased vascular iron content following dietary iron restriction in ApoE-deficient mice leads to lower matrix degradation capacity and increased plaque stability.

Pro-oxidative properties of flavonoids in human lymphocytes

The pro-oxidative properties of the four flavonoids, quercetin, morin, naringenin and hesperetin, in human lymphocyte system were investigated. Naringenin and hesperetin accelerated the oxidation of deoxyribose induced by Fe(3+)/H(2)O(2) in a concentration range of 0-200 microM, but quercetin and morin decreased it when the concentration was greater than 100 microM. The generation of hydrogen peroxide and the superoxide anion and the production of TBARS in lymphocytes were increased with increasing concentration of a flavonoid. Cell membrane protein thiols of the lymphocytes decreased when treated with the four flavonoids. Quercetin and hesperetin had no significant effect (p>0.05) on the activity of glutathione reductase, but morin and naringenin could inhibit the activity of the enzyme at a concentration of 200 microM, when compared to the control group. The glutathione S-transferase activity was slightly decreased by treatment with each of the four flavonoids only at a concentration of 200 microM. Therefore, the DNA damage in lymphocytes induced by the flavonoids in the model system might have been due to their stimulation of oxidative stress in the lymphocytes, which resulted in the decrease of cell membrane protein thiols, increase of lipid peroxidation in cell membrane and in the influence of the antioxidative enzyme activities.

Induction of heme oxygenase-1 expression in murine macrophages is essential for the anti-inflammatory effect of low dose 15-deoxy-Delta 12,14-prostaglandin J2

15-Deoxy-Delta 12,14-prostaglandin J2 (15d-PGJ2), a cyclopentenone prostaglandin, displays a potent anti-inflammatory effect at micromolar concentrations (>2 microM) through direct inhibition of nuclear factor (NF)-kappa B activation. Here we show that at submicromolar concentrations (0.1-0.5 microM) 15d-PGJ2 retains the ability to suppress the production of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) in lipopolysaccharide (LPS)-activated murine J774 macrophages under the conditions of a prolonged incubation (>12 h). Western blot analysis revealed that the expression of the cytoprotective enzyme, heme oxygenase-1 (HO-1), was induced and coincident with the anti-inflammatory action of 15d-PGJ2. Inhibition of HO-1 activity or scavenging carbon monoxide (CO), a byproduct derived from heme degradation, significantly attenuated the suppressive activity of 15d-PGJ2. Furthermore, LPS-induced NF-kappa B activation assessed by the inhibitory protein of NF-kappa B(I kappa B) degradation and p50 nuclear translocation was diminished in cells subjected to prolonged treatment with the low concentration of 15d-PGJ2. Treatment of cells with the protein synthesis inhibitor, cycloheximide, or the specific p38 MAP kinase inhibitor, SB203580, blocked the induction of HO-1 and suppression of LPS-induced I kappa B degradation mediated by 15d-PGJ2. Likewise, HO inhibitor and CO scavenger were effective in abolishing the inhibitory effects of 15d-PGJ2 on NF-kappa B activation induced by LPS. The functional role of CO was further demonstrated by the use of a CO releasing molecule, tricarbonyldichlororuthenium(II) dimer, which significantly suppressed LPS-induced nuclear translocation of p50 as assessed by confocal immunofluorescence. Collectively, these data suggest that even at submicromolar concentrations 15d-PGJ2 can exert an anti-inflammatory effect in macrophages through a mechanism that involves the action of HO/CO.

Microsatellite polymorphism in promoter of heme oxygenase-1 gene is associated with susceptibility to coronary artery disease in type 2 diabetic patients

Heme oxygenase is a rate-limiting enzyme in heme degradation, leading to the generation of free iron, biliverdin, and carbon monoxide. Induction of heme oxygenase-1 is implicated in the antioxidant defense mechanism and can modulate vascular function. To test the association of microsatellite polymorphism in the promoter region of human HO-1 gene with the risk of coronary artery disease (CAD) in type 2 diabetic patients, we examined the allele frequencies of (GT) (n) repeats in HO-1 gene in 474 patients with CAD and in 322 controls. A transient-transfection assay with HO-1 promoter/luciferase fusion constructs carrying various lengths of (GT) (n) repeats was performed to explore the regulatory effect of (GT) (n) repeats on HO-1 gene expression in cultured rat aortic smooth muscle cells. Serum thiobarbituric acid-reactive substances (TBARs), a measure of lipid peroxidation, was significantly higher in subjects carrying the L/L genotype (> or =32 repeats). Among type 2 diabetic subjects, the frequencies of the L alleles and proportion of genotypes with L alleles were significantly higher in those with CAD than in those without CAD. The adjusted odds ratio for CAD in type 2 diabetic patients with L alleles was 4.7 (95% confidence interval, 1.9-12.0, P=0.001). Transfection experiments in aortic smooth muscle cells revealed that HO-1 promoter/luciferase fusion constructs containing longer (GT) (n) repeats exhibited lower transcriptional activity. These results imply that the length polymorphism in the HO-1 gene promoter modulate the transcription of the gene in vascular cells. Type 2 diabetics carrying longer (GT) (n) repeats might have higher oxidative stress and increased susceptibility to the development of CAD.

Assembly of a robust, thermally stable porous cobalt(II) nicotinate framework based on a dicobalt carboxylate unit

A series of robust, thermally stable open-framework cobalt nicotinate compounds, Co(2)(H(2)O)[C(6)H(4)O(2)N](4).0.5CH(3)CH(2)OH.0.5H(2)O (1), Co(2)(H(2)O)[C(6)H(4)O(2)N](4) (2), and Co(2)(H(2)O)[C(6)H(4)O(2)N](4).C(6)H(5)CH(2)OH (3), based on rigid dimetallic carboxylate clusters as the basic building unit have been prepared. Single-crystal X-ray crystallographic analyses of 1 and 3 reveal the host framework possessing an effective channel area with the dimensions of 10.8 x 4.5 A. These channels can accommodate guest molecules of various sizes and shapes such as ethanol, water, and benzyl alcohol. Thermogravimetric analysis shows a two-step weight loss corresponding to the loss of guest molecules followed by the loss of coordinated water. The host framework is thermally stable up to 295 degrees C. The cobalt nicotinate host remains intact, even upon the removal of the guest to form compound 2 as revealed by single-crystal X-ray diffraction analysis. Crystal data for 1: Co(2)(H(2)O)[C(6)H(4)O(2)N)](4).0.5CH(3)CH(2)OH.0.5H(2)O, fw = 656.33, triclinic, space group P(-)1, a = 10.5407(2) A, b = 11.8266(3) A, c = 14.1122(2) A, alpha = 106.878(4) degrees, beta = 102.411(2) degrees, gamma = 111.011(3) degrees, V = 1467.9(5) A(3), Z = 2. Crystal data for 2: Co(2)(H(2)O)[C(6)H(4)O(2)N](4), fw = 624.28, triclinic, space group P(-)1, a = 10.507(3) A, b = 11.824(2) A, c = 14.113(3) A, alpha = 107.06(2) degrees, beta = 102.39(2) degrees, gamma = 111.105(16) degrees, V = 1459.5(6) A(3), Z = 2. Crystal data for 3: Co(2)(H(2)O)[C(6)H(4)O(2)N](4).C(6)H(5)CH(2)OH, fw = 732.42, triclinic, space group P(-)1, a = 10.6671(6) A, b = 12.0063(7) A, c = 14.0658(8) A, alpha = 106.7180(10) degrees, beta = 102.2790(10) degrees, gamma = 111.1900(10) degrees, V = 1504.1(6) A(3), Z = 2. The magnetic exchange coupling between the dicobalt centers for compounds 1 and 3 are analyzed on the basis of both the Curie-Weiss expression and a binuclear magnetic model. The negative values of the magnetic exchange coupling constant indicate the antiferromagnetic nature within the cobalt dimer.

Inhibition of thymidylate synthase activity by antisense oligodeoxynucleotide and possible role in thymineless treatment

Thymidylate synthase (TS) is an important target for chemotherapeutic treatment of cancer. However, efficacy of TS-targeted anticancer drugs is limited by the development of drug resistance as a result of TS gene amplification. In this work, a phosphorothioated antisense oligonucleotide (ODN), designated ATS-2, was used to suppress cellular synthesis of TS. ATS-2 at 0.2 microM concentration was mixed with lipofectin in a charge ratio of 1:1 and was used to treat the human embryonic kidney (HEK) cell line. A reduction of TS mRNA and protein was achieved. Furthermore, a dose-dependent reduction of cumulative viable cells of up to 98% was observed. Flow cytometer analysis of cell cycle progression indicates that ATS-2-treated cells were arrested and went into apoptosis at the S phase, possibly because of thymidine shortage, suggesting that ATS-2 is specifically effective for dividing cells. When used in combination with the anticancer drug FdUrd, ATS-2 exerted a additive inhibitory effect on cellular proliferation. To elucidate the possible role of cellular thymidine kinase (TdR kinase) in ATS-2 treatment, a second cell line, HeLa, was used. Both HEK and HeLa have similar rates of cell division and ODN uptake. In contrast to HEK, which was shown to have very low levels of TdR kinase activity in [(3)H]thymidine incorporation experiments, [(3)H]thymidine incorporation in HeLa was 15-fold greater than that of HEK. We found that HeLa cells were sensitive to FdUrd but were rather resistant to ATS-2. On the contrary, HEK cells were sensitive to ATS-2 but insensitive to FdUrd. Effects of ATS-2 and FdUrd are, therefore, complementary in thymineless treatment too.

Isolation and characterization of tilapia (Oreochromis mossambicus) insulin-like growth factors gene and proximal promoter region

To understand the molecular mechanism which controls the transcription of the insulin-like growth factors (IGFs) gene, we have cloned and sequenced the cDNA for the proximal promoter region of the tilapia IGFs gene and have characterized its activity by chloramphenicol acetyltransferase (CAT) transient transfected expression assays. Tilapia (Oreochromis mossambicus) IGF-I cDNA (549 bp) was amplified by PCR from single-stranded cDNA of growth hormone (GH)-induced liver RNA using a pair of oligonucleotides specific for fish IGF-I as amplification primers. Tilapia IGF-I and IGF-II 5' termini were analyzed by rapid amplification of cDNA 5' ends (5'RACE). Analysis of the 5'RACE results revealed two transcription start sites in IGF-I and one transcription start site in IGF-II. Different fragments of the 5' flanking region were transfected into human lung adenocarcinoma cells. In the cell line, maximum promoter activity was located in the distal 657 basepairs of the IGF-I 5' flanking region and in the distal 450 basepairs of the IGF-II 5' flanking region. The in vivo actions of the IGFs promoter on developmental stage expression were investigated further in transgenic zebrafish in which an IGFs promoter-driven green fluorescent protein (GFP) encoding the cDNA transgene was microinjected into embryos. Morphologic and RT-PCR studies of the transgenic zebrafish indicated that IGF-I promoter-driven GFP transcripts appeared for the first time in the 1-K-cell stage and the IGF-II promoter-driven GFP transcripts appeared for the first time in the 32-cell stage. Fluorescent (GFP) distribution was apparent within 48 h in IGF-II-transgenic zebrafish embryos, especially in eye, muscle, corpuscle, floor plate, horizontal myoseptum, yolk sac extension, and yolk sac. These results indicate that the IGF-I and IGF-II promoters are active in tissue and in a development-specific manner. Our findings also indicate that the IGF-II promoter influences the growth of fish embryos earlier than does IGF-I, and IGF-II has higher levels of expression than does IGF-I. These results suggest that the IGF-II promoter plays a growth factor role in teleost embryo development.

Pattern fusion in feature recognition neural networks for handwritten character recognition

B. Hussain and M.R. Kabuka (1994) proposed a feature recognition neural network to reduce the network size of neocognitron. However, a distinct subnet is created for every training pattern. Therefore, a big network is obtained when the number of training patterns is large. Furthermore, recognition rate can be hurt due to the failure of combining features from similar training patterns. We propose an improvement by incorporating the idea of fuzzy ARTMAP in the feature recognition neural network. Training patterns are allowed to be merged, based on the measure of similarity among features, resulting in a subnet being shared by similar patterns. Because of the fusion of training patterns, network size is reduced and recognition rate is increased.

Negative regulation of a heterologous promoter by human cytomegalovirus immediate-early protein IE2

The HCMV IE2 protein promiscuously activates transcription of many viral and cellular genes. IE2 also negatively autoregulates its own expression by binding to a strategically positioned IE2 binding site, called CRS, located immediately downstream of the TATA box of the HCMV major IE promoter. Here we show that IE2 is able to repress transcription driven by a heterologous promoter, RSV LTR. Repression of RSV LTR by IE2 is completely dependent of DNA sequences downstream of the TATA box of RSV LTR. A DNA sequence, 5'-CGATACAATAAACG-3', evidently matching the proposed CRS consensus sequence, is located between nucleotides -13 and +1 (relative to the transcription start site) of RSV LTR. Three lines of evidence support the notion that this RSV CRS element is involved in the IE2-mediated repression of RSV LTR. First, introduction of mutation to the RSV CRS element renders to the mutant RSV LTR resistance to IE2-mediated repression. Second, a mutant IE2 defective in DNA binding cannot downregulate transcription from RSV LTR. Third, IE2 specifically binds to the wild-type, but not the mutant, RSV CRS element in vitro. These data, in conjunction with previous works, demonstrate that IE2 can passively repress transcription of homologous and heterologous promoters that contain a CRS element.

Cytomegalovirus colitis in an immunocompetent old woman successfully treated with ganciclovir: a case report

Cytomegalovirus (CMV) diseases occur almost exclusively in the immunocompromised hosts. Persons most commonly affected are patients with acquired immunodeficiency syndrome (AIDS). On rare occasions, however, CMV diseases can be seen in apparently immunocompetent persons. A CMV colitis in a 68-year old immunocompetent woman presenting with watery diarrhea, malaise, and body weight loss of about 5 kg over a three week period is reported. Colonoscopy and mucosal biopsy revealed CMV colitis involving the sigmoid colon. Treatment for two weeks with ganciclovir (10 gm/kg/day I.V. in 2 divided doses) resulted in resolution of colitis and clinical symptoms without any noticeable side-effects. There was no relapse of infection by six months of follow-up. The possibility of CMV colitis should be considered in any elderly person with watery diarrhea, general debilitation, marked body weight loss and with negative stool cultures. CMV colitis may be more frequent than is usually believed. It has a favorable response to ganciclovir without further relapse after the successful treatment in patients with normal immune function.

Human cytomegalovirus immediate-early protein IE2 tethers a transcriptional repression domain to p53

The IE2 gene of human cytomegalovirus has been implicated in the development of coronary restenosis, and the gene product appears to inhibit p53-dependent transactivation. Here we describe an analysis of the IE2-p53 interaction. Repression of p53 function by IE2 requires two separable domains of IE2. The N terminus of IE2 interacts with p53. IE2 has little effect on the ability of p53 to bind specific DNA sequences. Reduction of the transactivation activity of p53 is caused by a transcriptional repression function contributed by the C-terminal domain of IE2. These findings suggest that IE2 may function as a transcriptional repressor, which is recruited to p53's target genes by interacting with p53.

Energy-dependent accumulation of neuron blockers causes selective inhibition of neurotransmitter uptake by brain synaptic vesicles

The effects of neuron blockers on neurotransmitter accumulation in synaptic vesicles were investigated. Upon addition of ATP, brain synaptic vesicles accumulated chlorpromazine, haloperidol, and propranolol against concentration gradients of more than 100-fold. Bioenergetic analysis indicated that the transmembrane pH gradient (delta pH) established by the vacuolar-type H(+)-ATPase is a direct driving force for these uptakes. Essentially the same results were obtained with vesicles from bovine adrenal chromaffin granules and proteoliposomes reconstituted with purified vacuolar H(+)-ATPase, indicating that the energy-dependent accumulation is due to diffusion and does not involve transport carriers specific for the blockers. Incubations of the two organelles with the blockers resulted in dissipation of delta pH and slight increase of membrane potential (delta psi) without affecting ATPase activity. Under the same conditions, uptake of dopamine or gamma-aminobutyrate (delta pH-driven transport) was inhibited by neuron blockers, whereas uptake of glutamate (delta psi-driven transport) was slightly stimulated. Thus, neuron blockers inhibited delta pH-driven uptake of neurotransmitter by dissipating the driving force. These results strongly suggest that synaptic vesicles are one of the target sites of neuron blockers.