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Ailing Li

Publications and source records attributed to Ailing Li.

13 recordsLinked to original sources
PubMed2006

Effect and mechanism of melatonin's action on the proliferation of human umbilical vein endothelial cells.

Melatonin is the major secretory product of the pineal gland and is considered an important natural oncostatic agent. The anticancer activity of melatonin is due to its immunomodulatory, anti-proliferative and antioxidative effects. At present there are no direct data available as to melatonin's possible influence on angiogenesis, which is a major biological mechanism responsible for tumor growth and dissemination. The current study investigated the influence of melatonin on angiogenesis. Human umbilical vein endothelial cells (HUVECs) were cultured, identified, and purified. Cell growth and viability, DNA fragmentation and cell cycle analyses were determined. To elucidate the mechanism of action of melatonin, Western blot analyses for P53, Bax and Bcl-2 expression were carried out. The results demonstrate the anti-proliferative and apoptosis-inducing effects of melatonin; these changes were associated with cell cycle arrest, upregulation of P53 and Bax and downregulation of Bcl-2. Taken together, our data showed that melatonin in high concentrations markedly reduces HUVECs proliferation, induces cellular apoptosis, and modulates cell cycle length. P53 and Bax/Bcl-2 expression changes may be involved in these actions of melatonin.

Cell Proliferation↗
PubMed2005

Molecular phylogeny of the domesticated silkworm, Bombyx mori, based on the sequences of mitochondrial cytochrome b genes.

Pupae from the Chinese wild mulberry silkworm, Bombyx mandarina, and 11 representative strains of the domesticated silkworm, Bombyx mori were selected for preparation of mitochondrial DNA. The 5'-end fragments of cytochrome b genes (Cytb) were generated by polymerase chain reaction products and sequenced directly. The homologous sequences of the Japanese B. mandarina and three strains of B. mori were from the GenBank database. The sequences of the 16 silkworm strains were analysed with DNASTAR software and a phylogenic tree was constructed using PHYLIP software. The result showed that: (i) The sequence divergence between the strains of B. mori and the Japanese B. mandarina was larger (5.4%-5.8%) compared with that between strains of B. mori and the Chinese B. mandarina (0.8% -1.9%). Analysis of clustering also showed that the sequences of B. mori strains and Chinese B. mandarina clustered into group (B group), while that of Japanese B. mandarina (A group) was outside this cluster. This may be evidence for the hypothesis that B. mori originated from Chinese B. mandarina. (ii) Among 14 strains of B. mori, sequence divergence was small and the most divergence was seen between strains Yanhe-1 and Chuxiong, whose sequences branched off from those of the other B. mori strains on the phylogenetic tree. From this and from historical records, we infer that the strains Yanhe-1 and Chuxiong originated independently from southwest China.

Animals↗
PubMed2005

Histologic variants of fibrous papule.

Fibrous papules (FPs) are common benign lesions usually of the face. Most are readily recognizable histologically, although several variants exist that may not be as easily diagnosed. These include hypercellular, clear cell, pigmented, pleomorphic, and inflammatory variants. A granular cell variant has also been described. We microscopically evaluated 212 FPs, and of those, 184 demonstrated features of one of the variants. We conclude that variants of FP may be encountered not uncommonly. Dermatopathologists should be aware of these to avoid misdiagnosis.

Angiofibroma↗
PubMed2005

Induction of xenogeneic islet transplantation tolerance by simultaneously blocking CD28-B7 and OX40-OX40L co-stimulatory pathways.

It has been demonstrated that prolonged graft survival can be achieved through inhibiting the activation of T cells, and addition of soluble CTLA4Ig and OX40Ig proteins to mixed lymphocyte reactions can effectively inhibit T cell proliferation. To explore the potential of this type of treatment in xenotransplantation, we infected streptozotocin-induced diabetic BalB/c mice (H-2d) (200 mg/kg, IV) with 5 x 10(8) pfu AdCTLA4Ig-IRES-OX40Ig on day 1 before islets transplantation through the tail vein. The results showed that this treatment prolonged the islet xenografts survival significantly. The reaction to exogenous glucose stimulation was normal and the cytokine secretion of the type Th1 cells was inhibited. The AdCTLA4Ig-IRES-OX40Ig-mediated treatment effectively induced the T cells into anergy and the Th1/Th2 cells into deviation. These results strongly supported the therapeutic potential of blockade of costimulation by AdCTLA4Ig-IRES-OX40Ig genes transfer in inducing the organ transplantation tolerance.

Abatacept↗
PubMed2004

Cytokines transduced bone marrow stromal cell lines promote immunohematopoietic reconstitution in mice after allogeneic bone marrow transplantation.

Impaired immune reconstitution following allogeneic T-cell depleted bone marrow transplantation (allo-TCD-BMT) is a major obstacle to its clinical application. Stromal cell line QXMSC1, established from bone marrow cells of BALB/c(H-2d), was transfected with murine IL-3 and/ or IL-2 gene, and injected into lethally irradiated C57BL/6(H2b) mice. We evaluated its effects on immunologic and hematopoietic reconstitution after allo-TCD-BMT. The results showed that QXMSC1-IL-3 + IL-2 could significantly increase the numbers of hematopoietic primitive progenitors (CFU-S), committed progenitors (CFU-GM, and BFU-E), and lymphocytes (CD8+ cells, CD4+ cells, and B cells). Similarly, immune functions of recipient mice were significantly enhanced in the QXMSC1-IL-3 + IL-2 group. In addition, QXMSC1-IL-3 or QXMSC1-IL-2 also exerted apparent effects on accelerating immune reconstitution, but these effects were far less than that of QXMSC1-IL-3 + IL-2. Our results demonstrated that stromal cell-mediated IL-3 and IL-2 gene therapy may be a potent approach in promoting immunologic and hematopoietic reconstitution after allo-TCD-BMT.

Animals↗
PubMed2003

Syringocystadenoma papilliferum contiguous to a verrucous cyst.

BACKGROUND: Syringocystadenoma papilliferum (SCAP) and verrucous cyst are two uncommon benign tumors. The simultaneous occurrence of the two lesions has not been reported before. METHODS: We report four cases of the simultaneous occurrence of the two rare lesions as so-called collision lesions with a review of the literature. CONCLUSION: The relationship of SCAP with viral infection needs further investigation.

Adenoma, Sweat Gland↗
PubMed2003

Granuloma annulare and malignant neoplasms.

The relationship between granuloma annulare (GA) and malignant neoplasms is uncertain. Several case reports and clinical correlation studies have addressed this issue; however, no review articles have summarized those reported cases and statistically analyzed the association. Fourteen case reports and two correlation studies directly addressing the relationship of GA and malignant neoplasms were found from the Medline database from 1966-2001. A total of 16 cases from case reports were available with the mean age of 54. Most of the GA patients had an atypical clinical presentation. The time between the onset of GA and the discovery of the malignant neoplasms varied from 18 months before (median = 5 months) to 7 years after (median = 42 months). More than half of those cases were associated with lymphoma. No definite relationship was found between GA and malignant neoplasms. Older patients with skin lesions not clinically typical of GA but that histologically resemble classic GA, may be considered for investigation of underlying malignant lymphoma or other malignancies.

Adult↗
PubMed2003

Experimental study on the function of cardiomyocytes.

This paper aimed at investigating the properties of cultured cardiomyocytes using microcirculatory and molecular technology to culture cardiomyocytes from different parts of the neonate Wistar rat's heart and record their spontaneous pulsation under time-lapse video microscopy, then analyze their activity and inspect their survival rate and apoptotic rate under natural and nitric oxide conditions. The pulsation frequency in cardiomtocytes of different parts in heart are: 78.5+/-11.0 beats/min in the atrium, 88.4+/-6.3 beats/min in the left ventricle, 90.3+/-7.9 beats/min in the right ventricle and 115.3 +/-11.4 beats/min in the cardiac apex, respectively, with an average frequency of 81.3 beats/min. Different concentrations of nitric oxide showed no effect on the frequency of cardiomyocyte pulsation. The survival rates of the above cardiomyocytes are 96.0%, 95.0%, 95.0%, and 95.3% respectively and 95.0% for the whole heart. The apoptotic rates are 1.3%, 1.1%, 4.8%, and 1.8% respectively and 5.1% for the whole heart. Different concentrations of nitric oxide had no effect on these results. Our study showed that cultured myocardial cells from different parts of the heart displayed various pulsation frequencies, and the frequency of the cardiac apex is the highest while the atrium is lowest. We also found that there is no statistically significant difference in the survival rates and apoptotic rates of different parts of the heart, and that nitric oxide has no effect on the beating frequency, survival rates or apoptotic rates of the cardiomyocytes in vitro.

Animals↗
PubMed2003

The mitogenic and anti-apoptotic activity of tumor conditioned medium on endothelium.

This study was designed to observe the effect of tumor conditioned medium (TCM) on the proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs were exposed to TCM from breast carcinoma cell line MDA-MB-231, then we measured their proliferation, apoptosis and cell cycle distribution by MTT and flow cytometery (FCM). Following the stimulation of TCM, HUVECs showed higher pro-mitogenic and anti-apoptotic ability than did the negative control group (ECGF-free medium with 20% FBS), but a similar ability to the positive control group (medium with ECGF and 20% FBS). From these results, we can conclude that breast carcinoma cell line MDA-MB-231 could secret soluble pro-angiogenic factors that induce HUVEC angiogenic switching, including cell cycle progression, proliferation and growth. The role and character of these factors remain to be further studied.

Angiogenesis Inducing Agents↗
PubMed2003

A proteomic study on cell cycle progression of endothelium exposed to tumor conditioned medium and the possible role of cyclin D1/E.

This study was designed to comprehensively analyze the differential expression of proteins from human umbilical vein endothelial cells (HUVECs) exposed to tumor conditioned medium (TCM) and to identify the key regulator in the cell cycle progression. The HUVECs were exposed to TCM from breast carcinoma cell line MDA-MB-231, then their cell cycle distribution was measured by flow cytometer (FCM). The role of protein in cell cycle progression was detected via two-dimensional polyacrylamide gel electrophoresis (2-DE) and western blotting. Following the stimulation of TCM, HUVECs showed a more cells in the S phase than did the negative control group (ECGF-free medium with 20% FBS), but the HUVECs' level was similar to the positive control group (medium with 25 micrograms/ml ECGF and 20% FBS). Increased expression of cyclin D1/E and some changes in other related proteins occurred after incubation with TCM. From our results, we can conclude that breast carcinoma cell line MDA-MB-231 may secrete soluble pro-angiogenic factors that induce the HUVEC angiogenic switch, during which the expression of cell cycle regulator cyclin D1/E increases and related proteins play an important role in this process.

Angiogenesis Inducing Agents↗
PubMed2002

Coumarins and pyranocoumarins, potential novel pharmacophores for inhibition of measles virus replication.

A series of coumarin and pyranocoumarin analogues were evaluated in vitro for antiviral efficacy against measles virus (MV), strain Chicago. Of the 22 compounds tested for inhibition, six were found to have selectivity indices greater than 10. These were compounds 5-hydroxy-7-propionyloxy-4-propylcoumarin (2a), 5,7-bis(tosyloxy)-4-propylcoumarin (7); 5-hydroxy-4-propyl-7-tosyloxy-coumarin (8); 6,6-dimethyl-9-propionyloxy-4-propyl-2H,6H-benzo[1,2-b:3,4-b']dipyran-2-one (9); 6,6-dimethyl-9-pivaloyloxy-4-propyl-2H,6H-benzo[1,2-b:3,4-b']dipyran-2-one (10); and 7,8-cis-10,11,12-trans-4-propyl-6,6,10,11-tetramethyl-7,8,9-trihydroxy-2H,6H,12H-benzo[1 ,2-b:3,4-b':5,6-b'']tripyran-2-one (18). Three of the active drugs were propyl coumarin analogues (2a, 7 and 8), two were dipyranone or chromeno-coumarins (9 and 10), and one was a benzotripyranone with a coumarin nucleus (18). Some appeared to be rather specific and potent inhibitors of MV with EC50 values ranging from 0.2 to 50 microg/ml and the majority of the EC50 values being less than 5 pg/ml. The compounds inhibited an additional nine strains of MV, and in virucidal tests the drugs did not physically disrupt the virion to inhibit virus replication. The inhibitory activity for one of the compounds tested (7) was somewhat dependent on virus concentration and it was still active when added to cells up to 24 h after virus exposure. When used in combination with ribavirin, compound 7 appeared not to profoundly affect the antiviral efficacy of ribavirin or its cell-associated toxicity. However, a slightly antagonistic MV-inhibitory effect was observed at the highest concentration of ribavirin used in combination with most concentrations of compound 7 tested. This and related compounds may be valuable leads in the development of a potent and selective class of MV inhibitors that could be used in future in the clinic.

Animals↗
PubMedDate not supplied

Recombinant human prolactin improves antitumor effects of murine natural killer cells in vitro and in vivo.

OBJECTIVE: To verify the effect of prolactin on natural killer (NK) cells in vivo and its implications for NK cell immunotherapy. METHODS: Recombinant human prolactin (rhPRL; 30 microg, i.p.) was administered to BALB/c mice and severe combined immunodeficiency (SCID) mice 1 day before harvesting splenocytes for (51)Cr release assay to examine the effects of rhPRL on NK cells of normal mice. rhPRL (10 microg, i.p., every other day for a total of 5 injections) was administered to BALB/c mice after syngeneic bone marrow transplantation (SBMT) to determine its effects on NK cell reconstitution. CT26 tumor cells were injected into BALB/c mice intravenously on day 0, and interleukin (IL)-15-cocultured activated syngeneic NK cells (IL-15-NK) from SCID mice were intravenously injected into tumor-bearing BALB/c mice on day 1. The improvement of antimetastasis effects and survival of tumor-bearing mice by rhPRL were checked. RESULTS: BALB/c and SCID mice receiving one rhPRL injection exhibited a significant increase in cellular cytotoxicity against YAC-1 target tumor cells; the specific lysis was enhanced from 12.5 to 17.3% in BALB/c mice and from 27.8 to 51.2% in SCID mice. BALB/c mice continuously receiving rhPRL injections exhibited significant increases in NK cell (DX5-positive) contents and cellularity in both the bone marrow and spleen in the SBMT model. The bone marrow NK cell contents were improved from 1.53 to 3.13% after rhPRL injection. NK cells from SCID mice were then cultured with recombinant human IL-15 (rhIL-15; 6000 IU/ml), rhPRL (10 ng/ml) or rhIL-15 plus rhPRL for 25 days. The cytotoxicity and cellularity were enhanced by rhPRL when tested on day 10, when comparing the rhIL-15 plus rhPRL group with the rhIL-15 group or rhPRL group, respectively. In the adoptive cellular immunotherapy study, the IL-15-NK plus IL-15 plus rhPRL group showed significantly lower numbers of lung metastases and longer survival than the IL-15-NK plus IL-15 group; the mean survival interval was prolonged from 31.5 to 53.7 days. CONCLUSION: These results indicate that rhPRL is possibly an important regulator of NK cells and a potential biologic product for immunotherapy.

Animals↗