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1.  Zn-Driven Discovery of a Hydrothermal Vent Fungal Metabolite Clavatustide C, and an Experimental Study of the Anti-Cancer Mechanism of Clavatustide B 
Marine Drugs  2014;12(6):3203-3217.
A naturally new cyclopeptide, clavatustide C, was produced as a stress metabolite in response to abiotic stress elicitation by one of the hydrothermal vent fluid components Zn in the cultured mycelia of Aspergillus clavatus C2WU, which were isolated from Xenograpsus testudinatus. X. testudinatus lives at extreme, toxic habitat around the sulphur-rich hydrothermal vents in Taiwan Kueishantao. The known compound clavatustide B was also isolated and purified. This is the first example of a new hydrothermal vent microbial secondary metabolite produced in response to abiotic Zn treatment. The structures were established by spectroscopic means. The regulation of G1-S transition in hepatocellular carcinoma cell lines by clavatustide B was observed in our previous study. The purpose of the present study was to verify these results in other types of cancer cell lines and elucidate the possible molecular mechanism for the anti-cancer activities of clavatustide B. In different human cancer cell lines, including pancreatic cancer (Panc-1), gastric cancer (MGC-803), colorectal cancer (SW-480), retinoblastoma (WERI-Rb-1) and prostate cancer (PC3), clavatustide B efficiently suppressed cell proliferations in a dose-dependent manner. Although different cancer cell lines presented variety in Max effect dose and IC50 dose, all cancer cell lines showed a lower Max effect dose and IC50 dose compared with human fibroblasts (hFB) (p < 0.05). Moreover, significant accumulations in G1 phases and a reduction in S phases (p < 0.05) were observed under clavatustide B treatment. The expression levels of 2622 genes including 39 cell cycle-associated genes in HepG2 cells were significantly altered by the treatment with 15 μg/mL clavatustide B after 48 h. CCNE2 (cyclin E2) was proved to be the key regulator of clavatustide B-induced G1-S transition blocking in several cancer cell lines by using real-time PCR.
PMCID: PMC4071572  PMID: 24879544
clavatustides; stress-driven discovery; hydrothermal vent; anti-cancer
2.  Acute myeloid leukemia is characterized by Wnt pathway inhibitor promoter hypermethylation 
Leukemia & lymphoma  2010;51(9):1711-1719.
Nuclear localization of non-phosphorylated, active β-catenin is a measure of Wnt pathway activation and is associated with adverse outcome in patients with acute myeloid leukemia (AML). While genetic alterations of the Wnt pathway are infrequent in AML, inhibitors of this pathway are silenced by promoter methylation in other malignanices. Leukemia cell lines were examined for Wnt pathway inhibitor methylation and total β-catenin levels, and had frequent methylation of Wnt inhibitors and upregulated β-catenin by Western blot and immunofluorescence. One hundred sixty-nine AML samples were examined for methylation of Wnt inhibitor genes. Diagnostic samples from 72 patients with normal cytogenetics who received standard high-dose induction chemotherapy were evaluated for associations between methylation and event-free or overall survival. Extensive methylation of Wnt pathway inhibitor genes was observed in cell lines, and 89% of primary AML samples had at least one methylated gene: DKK1 (16%), DKK3 (8%), RUNX3 (27%), sFRP1 (34%), sFRP2 (66%), sFRP4 (9%), sFRP5 (54%), SOX17 (29%), and WIF1 (32%). In contrast to epithelial tumors, methylation of APC (2%) and RASSF1A (0%) was rare. In patients with AML with normal cytogenetics, sFRP2 and sFRP5 methylation at the time of diagnosis was associated with an increased risk of relapse, and sFRP2 methylation was associated with an increased risk for death. In patients with AML: (a) there is a high frequency of Wnt pathway inhibitor methylation; (b) Wnt pathway inhibitor methylation is distinct from that observed in epithelial malignancies; and (c) methylation of sFRP2 and sFRP5 may predict adverse clinical outcome in patients with normal karyotype AML.
PMCID: PMC4000011  PMID: 20795789
Cytogenetics; DNA methylation; epigenetics; leukemia; Wnt pathway
3.  Neuritogenic Monoglyceride Derived from the Constituent of a Marine Fish for Activating the PI3K/ERK/CREB Signalling Pathways in PC12 Cells 
A neuritogenic monoglyceride, 1-O-(myristoyl) glycerol (MG), was isolated from the head of Ilisha elongate using a PC12 cell bioassay system, and its chemical structure was elucidated using spectroscopic methods. MG significantly induced 42% of the neurite outgrowth of PC12 cells at a concentration of 10 μM. To study the structure-activity relationships of MG, a series of monoglycerides was designed and synthesised. Bioassay results indicated that the alkyl chain length plays a key role in the neuritogenic activity of the monoglycerides. The groups that link the propane-1,2-diol and alkyl chain were also investigated. An ester linkage, rather than an amido one, was found to be optimal for neuritogenic activity. Therefore, 1-O-(stearoyl) glycerol (SG), which induces 57% of the neurite outgrowth of PC12 cells at 10 μM, was determined to be a lead compound for neuritogenic activity. We then investigated the mechanism of action of neurite outgrowth induced by SG on PC12 cells using protein specific inhibitors and Western blot analysis. The mitogen-activated kinase/ERK kinase (MEK) inhibitor U0126 and the phosphatidylinositol-3 kinase (PI3K) inhibitor LY294002 significantly decreased neurite outgrowth. At the same time, SG increased phosphorylation of CREB in protein level. Thus, SG-induced neuritogenic activity depends on the activation of the extracellular-regulated protein kinase (ERK), cAMP responsive element-binding protein (CREB) and PI3K signalling pathways in PC12 cells.
PMCID: PMC3876105  PMID: 24351811
1-O-(myristoyl) glycerol; neuritogenic activity; Ilisha elongate; PC12 cells; 1-O-(stearoyl) glycerol; ERK
4.  Two Novel Hepatocellular Carcinoma Cycle Inhibitory Cyclodepsipeptides from a Hydrothermal Vent Crab-Associated Fungus Aspergillus clavatus C2WU 
Marine Drugs  2013;11(12):4761-4772.
Two novel cyclodepsipeptides containing an unusual anthranilic acid dimer and a d-phenyllactic acid residues, clavatustides A (1) and B (2), were identified from cultured mycelia and broth of Aspergillus clavatus C2WU isolated from Xenograpsus testudinatus, which lives at extreme, toxic habitat around the sulphur-rich hydrothermal vents in Taiwan Kueishantao. This is the first example of cyclopeptides containing an anthranilic acid dimer in natural products, and the first report of microbial secondary metabolites from the hydrothermal vent crab. Clavatustides A (1) and B (2) suppressed the proliferation of hepatocellular carcinoma (HCC) cell lines (HepG2, SMMC-7721 and Bel-7402) in a dose-dependent manner, and induced an accumulation of HepG2 cells in G1 phase and reduction of cells in S phase.
PMCID: PMC3877885  PMID: 24317468
cyclodepsipeptide; Aspergillus clavatus; hydrothermal vent; carcinoma cycle inhibitory
5.  Pretherapeutic Plasma Pro- and Anti- Inflammatory Mediators Are Related to High Risk of Oral Mucositis in Pediatric Patients with Acute Leukemia: A Prospective Cohort Study 
PLoS ONE  2013;8(5):e64918.
This prospective study evaluated clinical risk indicators as well as pro- and anti- inflammatory mediators at the time of malignancy diagnosis in relation to chemotherapy-related oral mucositis in pediatric population.
Patients (n = 104) under 18 years of age with primary malignancies and undergoing chemotherapy were included. Potential risk indicators were analyzed using binary logistic regression with oral mucositis as the outcome. In a subgroup (n = 35), plasma samples at the time of malignancy diagnosis were analyzed for inflammatory cytokines and an antimicrobial protein pro-LL-37 (hCAP18).
In the multivariable model, type of malignancy diagnosis was significantly associated with oral mucositis, with highest risk of oral mucositis in patients with acute leukemia compared to those with lymphoma or solid tumors. At the time of malignancy diagnosis, plasma from patients with acute leukemia displayed higher concentrations (P<0.05) of IL-6, IL-8, IL-10, and TNF-α and lower levels of pro-LL-37 (P<0.001).
The results imply that pretherapeutic high levels of inflammatory cytokines and low levels of pro-LL-37 in plasma might contribute to the high incidence of oral mucositis in patients with acute leukemia. These findings may add to our understanding of the predispositions to oral mucositis in children with malignancies.
PMCID: PMC3669020  PMID: 23741421
7.  Surveillance of Antimicrobial Susceptibility Patterns among Shigella Species Isolated in China during the 7-Year Period of 2005-2011 
Annals of Laboratory Medicine  2013;33(2):111-115.
Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with antibiotics is recommended for shigellosis, but the options are limited due to globally emerging resistance. This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella in China.
We studied the antimicrobial resistance profiles of 308 Shigella spp. strains (260 S. flexneri, 40 S. sonnei, 5 S. boydii, and 3 S. dysenteriae) isolated from fecal samples of patients (age, from 3 months to 92 yr) presenting with diarrhea in different districts of Anhui, China. The antimicrobial resistance of strains was determined by the agar dilution method according to the CSLI guidelines.
The most common serogroup in the Shigella isolates was S. flexneri (n=260, 84.4%), followed by S. sonnei (n=40, 13.0%). The highest resistance rate was found for nalidixic acid (96.4%), followed by ampicillin (93.2%), tetracycline (90.9%), and trimethoprim/sulfamethoxazole (80.8%). Among the isolates tested, 280 (91.0%) were multidrug resistant (resistant to ≥2 agents). The most common resistance pattern was the combination of ampicillin, tetracycline, and trimethoprim/sulfamethoxazole (70.8%). Resistance to ampicillin and tetracycline were more common among S. flexneri than among S. sonnei isolates.
S. flexneri is predominant in Anhui, China, and its higher antimicrobial resistance rate compared with that of S. sonnei is a cause for concern. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in Shigella. The recommendations for antimicrobial treatment must be updated regularly based on surveillance results.
PMCID: PMC3589635  PMID: 23482897
Antimicrobial susceptibility; Antimicrobial resistance; Shigella
8.  Electronically-measured adherence to immunosuppressive medications and kidney function after deceased donor kidney transplantation* 
Clinical transplantation  2010;25(2):E124-E131.
Non-adherence with immunosuppressive medications can result in allograft rejection and eventually allograft loss.
In a racially diverse population, we utilized microelectronic cap monitors to determine the association of adherence with a single immunosuppressive medication and kidney allograft outcomes post-transplantation. This prospective cohort study enrolled 243 patients from eight transplant centers to provide adherence and kidney allograft outcomes data. To determine the association of adherence with change in estimated glomerular filtration rate (eGFR), we fit mixed effects models with the outcome being change in eGFR over time. We also fit Cox proportional hazards models to determine the association of adherence with time to persistent 25% and 50% decline in eGFR.
The distribution of adherence post-transplant was as follows: 164 (68%), 49 (20%) and 30 (12%) had >85–100%, 50–85% and <50% adherence, respectively. 79 (33%) and 36 (15%) of the subjects experienced a persistent 25% decline in eGFR or allograft loss and 50% decline in eGFR or allograft loss during follow-up. Adherence was not associated with acute rejection or 25% decline or 50% decline in eGFR. In the adjusted and unadjusted model, adherence and black race were not associated with change in eGFR over time.
Non-adherence with a single immunosuppressive medication, was not associated with kidney allograft outcomes.
PMCID: PMC3566245  PMID: 20977496
kidney transplant; adherence; renal function
9.  Plasmid-Mediated Quinolone Resistance in Extended-Spectrum-β-Lactamase- and AmpC β-Lactamase-Producing Serratia marcescens in China 
We investigated the prevalence of plasmid-mediated quinolone resistance (PMQR) determinants and examined the association of these determinants with extended-spectrum β-lactamases (ESBLs) and/or plasmid-mediated AmpC β-lactamases (pAmpCs) in Serratia marcescens isolates in China. In this study, the presence of PMQR determinants was significantly related to the coproduction of ESBLs and/or pAmpCs (CTX-M-14, SHV-5, DHA-1, and ACT-1), among which CTX-M-14 was the most common gene type.
PMCID: PMC3421568  PMID: 22664965
10.  Invasive ductal breast cancer metastatic to the sigmoid colon 
The most common sites of breast cancer metastasis are the bone, lung, liver and brain. However, colonic metastases from breast cancer are very rare in the clinic. We describe an unusual case of sigmoid colonic metastasis from invasive ductal breast cancer. With this report, we should increase the clinical awareness that any patient with a colorectal lesion and a history of malignancy should be considered to have a metastasis until proven otherwise. Early diagnosis is very important, which enables prompt initiation of systemic treatment, such as chemotherapy, endocrine therapy or both, thus avoiding unnecessary radical surgical resection and improving the prognosis.
PMCID: PMC3547804  PMID: 23181599
Breast cancer; Sigmoid colon; Metastasis; Invasive ductal cancer
11.  Emergence of serogroup C meningococcal disease associated with a high mortality rate in Hefei, China 
BMC Infectious Diseases  2012;12:205.
Neisseria meningitidis serogroup C has emerged as a cause of epidemic disease in Hefei. The establishment of serogroup C as the predominant cause of endemic disease has not been described.
We conducted national laboratory-based surveillance for invasive meningococcal disease during 2000–2010. Isolates were characterized by pulsed-field gel electrophoresis and multilocus sequence typing.
A total of 845 cases of invasive meningococcal disease were reported. The incidence increased from 1.25 cases per 100,000 population in 2000 to 3.14 cases per 100,000 in 2003 (p < 0.001), and peaked at 8.43 cases per 100,000 in 2005. The increase was mainly the result of an increase in the incidence of serogroup C disease. Serogroup C disease increased from 2/23 (9%) meningococcal cases and 0.11 cases per 100,000 in 2000 to 33/58 (57%) cases and 1.76 cases per 100,000 in 2003 (p < 0.01). Patients infected with serogroup C had serious complications more frequently than those infected with other serogroups. Specifically, 161/493 (32.7%) cases infected with serogroup C had at least one complication. The case-fatality rate of serogroup C meningitis was 11.4%, significantly higher than for serogroup A meningitis (5.3%, p = 0.021). Among patients with meningococcal disease, factors associated with death in univariate analysis were age of 15–24 years, infection with serogroup C, and meningococcemia.
The incidence of meningococcal disease has substantially increased and serogroup C has become endemic in Hefei. The serogroup C strain has caused more severe disease than the previously predominant serogroup A strain.
PMCID: PMC3459715  PMID: 22943188
Neisseria meningitidis; Serogroup C strain; Incidence
12.  Paroxysmal Supraventricular Tachycardia in an Infant with Hand, Foot, and Mouth Disease 
Annals of Dermatology  2012;24(2):200-202.
An 11-month-old male infant was admitted to our hospital with fever, fussiness, poor feeding, vomiting, and tachypnea for two days prior. Physical examination revealed sporadic papules and vesicles occurring on his hands, feet, face, and perianal mucosa. Enterovirus 71 was identified from both throat swab and vesicle fluid using virus isolation techniques. The patient's heart rate fluctuated in a very narrow range from 180~210/beats/min regardless of his physiologic state. An electrocardiogram showed P-waves buried within or occurring just after regular, narrow, QRS complexes. The patient was diagnosed as having hand, foot, and mouth disease in combination with paroxysmal supraventricular tachycardia (PSVT). The child recovered well with symptomatic treatment, including intravenous administration of acyclovir, glucocorticoids, immunoglobulin, adenosine, and sotalol. PSVT was terminated within 36 hours of hospitalization. The skin lesions became crusted on the third day, and then proceeded to heal spontaneously. Here we report on this unusual case and review the associated literature.
PMCID: PMC3346912  PMID: 22577272
Electrocardiography; Hand; foot and mouth disease; Enterovirus 71; Paroxysmal supraventricular tachycardia
13.  Different sperm sources and parameters can influence intracytoplasmic sperm injection outcomes before embryo implantation*  
To evaluate the effects of sperm with different parameters and sources on the outcomes of intracytoplasmic sperm injection (ICSI), 1972 ICSI cycles were analyzed retrospectively. Groups 1 to 5 were composed of cycles using ejaculated sperm and were grouped according to sperm quantity, quality, and morphology into normal (288 cycles), or mild (329 cycles), moderate (522 cycles), severe (332 cycles), and extremely severe (171 cycles) oligozoospermia and/or asthenozoospermia and/or teratozoospermia (OAT) groups. Group 6 was composed of 250 cycles using testicular or epididymal sperm, and Group 7 consisted of 80 cycles using frozen-thawed sperm. We found that fertilization rates were gradually reduced from Groups 1 to 6, and reached statistical difference in Groups 5 and 6 (P<0.05). The high-quality embryo rate was higher in Group 1 than in Groups 2, 3, 5, 6, and 7 (P<0.05). No statistical differences were observed in the rates of embryo cleavage, clinical pregnancy, miscarriage, live-birth, premature birth, low birth weight, weeks of premature birth, average birth weight, or sex ratio for all seven groups (P>0.05). A total of nine cases of malformation were observed, with a malformation rate of 1.25% (9/719). In conclusion, different sperm sources and parameters can affect ICSI outcomes before embryo implantation. A full assessment of offspring malformation will require further study using a larger sample size.
PMCID: PMC3251746  PMID: 22205614
Intracytoplasmic sperm injection (ICSI); Sperm; Sperm source; Sperm parameters; Malformation
14.  Mutations in the ELANE Gene are Associated with Development of Periodontitis in Patients with Severe Congenital Neutropenia 
Journal of Clinical Immunology  2011;31(6):936-945.
Patients with severe congenital neutropenia (SCN) often develop periodontitis despite standard medical and dental care. In light of previous findings that mutations in the neutrophil elastase gene, ELANE, are associated with more severe neutropenic phenotypes, we hypothesized an association between the genotype of SCN and development of periodontitis.
Fourteen Swedish patients with SCN or cyclic neutropenia harboring different genetic backgrounds were recruited for periodontal examination. Peripheral blood, gingival crevicular fluid (GCF), and subgingival bacterial samples were collected. The levels of cytokines and antibacterial peptides were determined in GCF and plasma by multiplex immunoassay and immunoblotting, respectively. Subgingival bacterial samples were analyzed using 16S rDNA pyrosequencing.
ELANE mutations correlated with more severe periodontal status than the HAX1 or unknown mutations in patients with SCN. The subjects with mutant ELANE had higher levels of IL-1β in GCF. Using principal coordinate analysis of the subgingival microbiota, patients with ELANE mutations and reference subjects with periodontitis tended to cluster differently from patients with HAX1 or unknown mutations and non-periodontitis reference subjects.
This study demonstrates an association between ELANE mutations in SCN and the development of periodontitis with skewed subgingival microbiota, indicating a potential role of ELANE mutations in the pathogenesis of periodontitis.
PMCID: PMC3223588  PMID: 21796505
Kostmann neutropenia; neutrophil elastase 2; periodontal diseases; subgingival microflora
15.  Progressive chromatin repression and promoter methylation of CTNNA1 associated with advanced myeloid malignancies 
Cancer research  2009;69(21):8482-8490.
Complete loss or deletion of the long arm of chromosome 5 is frequent in myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML). The putative gene(s) deleted and responsible for the pathogenesis of these poor prognosis hematological disorders remain controversial. This study is a comprehensive analysis of previously implicated and novel genes for epigenetic inactivation in AML and MDS. In 146 AML cases, methylation of CTNNA1 was frequent, and more common in AML patients with 5q deletion (31%) than those without 5q deletion (14%), while no methylation of other 5q genes was observed. In 31 MDS cases, CTNNA1 methylation was only found in high risk MDS (≥RAEB2), but not in low risk MDS (
PMCID: PMC3081599  PMID: 19826047
del(5q); monosomy 5; CTNNA1; methylation; myelodysplastic syndrome; acute myelogenous leukemia; methylation; Progressive silencing; AML transformation
Oncogene  2010;29(17):2467-2476.
The tumor suppressor gene HYPERMETHYLATED IN CANCER 1 (HIC1), which encodes a transcriptional repressor, is epigenetically inactivated in various human cancers. Here, we show that HIC1 is a direct transcriptional repressor of the gene encoding ephrin-A1, a cell surface ligand implicated in the pathogenesis of epithelial cancers. We also show that mouse embryos lacking both Hic1 alleles manifest developmental defects spatially associated with misexpression of ephrin-A1, and that overexpression of ephrin-A1 is a feature of tumors arising in Hic1 heterozygous mice in which the remaining wild-type allele is epigenetically silenced. In breast cancer, we find that ephrin-A1 expression is common in vivo, but that in cell culture, expression of the EphA receptors is predominant. Restoration of HIC1 function in breast cancer cells leads to a reduction in tumor growth in vivo, an effect that can be partially rescued by co-overexpression of ephrin-A1. Interestingly, overexpression of ephrin-A1 in vitro triggers downregulation of EphA2 and EphA4 levels, resulting in an expression pattern similar to that seen in vivo. We conclude that Hic1 spatially restricts ephrin-A1 expression in development, and that upregulated expression of ephrin-A1 resulting from epigenetic silencing of HIC1 in cancer cells may be an important mechanism in epithelial malignancy.
PMCID: PMC3025282  PMID: 20154726
Hic1; Ephrin-A1; EphA2; EphA4
Oncogene  2010;29(25):3619-3629.
Aneurysmal bone cyst (ABC) is an aggressive, pediatric bone tumor characterized by extensive destruction of the surrounding bone. Though first described over 60 years ago, its molecular etiology remains poorly understood. Recent work revealed that ABCs harbor translocation of TRE17/USP6, leading to its transcriptional upregulation. TRE17 encodes a ubiquitin-specific protease (USP), and a TBC domain that mediates binding to the Arf6 GTPase. However, the mechanisms by which TRE17 overexpression contributes to tumor pathogenesis, and the role of its USP and TBC domains are unknown. ABCs are characterized by osteolysis, inflammatory recruitment, and extensive vascularization, processes in which matrix proteases play a prominent role. This led us to explore whether TRE17 regulates the production of matrix metalloproteinases (MMPs). In the current study, we demonstrate that TRE17 is sufficient to induce expression of MMP-9 and MMP-10, in a manner requiring its USP activity, but not its ability to bind Arf6. TRE17 induces transcription of MMP-9 through activation of NFκB, mediated in part by the GTPase RhoA and its effector kinase, ROCK. Furthermore, xenograft studies demonstrate that TRE17 induces formation of tumors that reproduce multiple features of ABC, including a high degree of vascularization, with an essential role for the USP domain. In sum, these studies reveal that TRE17 is sufficient to initiate tumorigenesis, identify MMPs as novel TRE17 effectors that likely contribute to ABC pathogenesis, and define the underlying signaling mechanism of their induction.
PMCID: PMC2892027  PMID: 20418905
TRE17/USP6; aneurysmal bone cyst; MMP-9; Arf6; NFκB; RhoA
AIM: To investigate the role of enhancer of zeste homologue 2 (EZH2) and STAT6 immunohistochemistry in the evaluation of clinical stages and prognosis of colorectal cancer (CRC).
METHODS: The expression patterns were examined by immunohistochemistry in both tumor and adjacent non-neoplastic tissues of 119 CRC patients who underwent operation during the time period from 2002 to 2004.
RESULTS: The positive rates of EZH2 and STAT6 in CRC cases were 69.7% (83 of 119) and 60.5% (72 of 119), respectively, and there was significant difference when compared with tumor adjacent non-neoplastic tissues (P < 0.05). In all CRC cases, patients with EZH2-positive, or STAT6-positive expression had lower survival rates than those with EZH2-negative or STAT6-negative expression (P = 0.002 and P = 0.005, respectively). Co-expression of EZH2 and STAT6 showed significantly higher levels in CRC cases of high clinical TNM stages (P = 0.001), and the expression of STAT6 was also correlated with lymph node metastasis and distant metastasis (P = 0.001 and P = 0.016, respectively). Multivariate analysis revealed that EZH2 expression was an independent prognostic indicator of CRC (P = 0.039).
CONCLUSION: EZH2 and STAT6 expressions have significant values in distinguishing clinical stages of CRC and predicting the prognosis of the patients.
PMCID: PMC2874149  PMID: 20480530
Colorectal Neoplasms; Enhancer of zeste homologue 2; STAT6; Immunohistochemistry
PLoS ONE  2010;5(3):e9737.
Defensins are antimicrobial peptides expressed by plants and animals. In mammals there are three subfamilies of defensins, distinguished by structural features: α, β and θ. Alpha and β-defensins are linear peptides with broad anti-microbial activity that are expressed by many mammals including humans. In contrast, θ-defensins are cyclic anti-microbial peptides made by several non-human primates but not humans. All three defensin types have anti-HIV-1 activity, but their mechanisms of action differ. We studied the anti-HIV-1 activity of one defensin from each group, HNP-1 (α), HBD-2 (β) and RTD-1 (θ). We examined how each defensin affected HIV-1 infection and demonstrated that the cyclic defensin RTD-1 inhibited HIV-1 entry, while acyclic HNP-1 and HBD-2 inhibited HIV-1 replication even when added 12 hours post-infection and blocked viral replication after HIV-1 cDNA formation. We further found that all three defensins downmodulated CXCR4. Moreover, RTD-1 inactivated X4 HIV-1, while HNP-1 and HBD-2 inactivated both X4 and R5 HIV-1. The data presented here show that acyclic and cyclic defensins block HIV-1 replication by shared and diverse mechanisms. Moreover, we found that HNP-1 and RTD-1 directly inhibited firefly luciferase enzymatic activity, which may affect the interpretation of previously published data.
PMCID: PMC2840026  PMID: 20305815
Unregulated activation of mast cells can contribute to the pathogenesis of inflammatory and allergic diseases, including asthma, rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis(1;2). Absence of mast cells in animal models can lead to impairment in the innate immune response to parasites and bacterial infections(3–5). Aberrant clonal accumulation and proliferation of mast cells can result in a variety of diseases ranging from benign cutaneous mastocytosis to systemic mastocytosis or mast cell leukemia(6). Understanding mast cell differentiation provides important insights into mechanisms of lineage selection during hematopoiesis and can provide targets for new drug development to treat mast cell disorders,. In this review, we discuss controversies related to development, sites of origin,, and the transcriptional program of mast cells.
PMCID: PMC2478671  PMID: 18406636
Mast cells; transcription factors; GATA; PU.1; Mitf
PLoS Genetics  2009;5(3):e1000413.
One of the earliest morphogenetic processes in the development of many animals is epiboly. In the zebrafish, epiboly ensues when the animally localized blastoderm cells spread, thin over, and enclose the vegetally localized yolk. Only a few factors are known to function in this fundamental process. We identified a maternal-effect mutant, betty boop (bbp), which displays a novel defect in epiboly, wherein the blastoderm margin constricts dramatically, precisely when half of the yolk cell is covered by the blastoderm, causing the yolk cell to burst. Whole-blastoderm transplants and mRNA microinjection rescue demonstrate that Bbp functions in the yolk cell to regulate epiboly. We positionally cloned the maternal-effect bbp mutant gene and identified it as the zebrafish homolog of the serine-threonine kinase Mitogen Activated Protein Kinase Activated Protein Kinase 2, or MAPKAPK2, which was not previously known to function in embryonic development. We show that the regulation of MAPKAPK2 is conserved and p38 MAP kinase functions upstream of MAPKAPK2 in regulating epiboly in the zebrafish embryo. Dramatic alterations in calcium dynamics, together with the massive marginal constrictive force observed in bbp mutants, indicate precocious constriction of an F-actin network within the yolk cell, which first forms at 50% epiboly and regulates epiboly progression. We show that MAPKAPK2 activity and its regulator p38 MAPK function in the yolk cell to regulate the process of epiboly, identifying a new pathway regulating this cell movement process. We postulate that a p38 MAPKAPK2 kinase cascade modulates the activity of F-actin at the yolk cell margin circumference allowing the gradual closure of the blastopore as epiboly progresses.
Author Summary
One of the earliest cell movement processes in the development of many animals is epiboly. In the zebrafish, epiboly ensues when the blastoderm cells spread over and enclose the yolk cell. Only a few factors are known to function in this fundamental process. We identified a maternal-effect mutant, betty boop (bbp), which displays a novel defect in epiboly, wherein the blastoderm margin constricts dramatically, precisely when half of the yolk cell is covered by the blastoderm, causing the yolk cell to burst. We demonstrate that Bbp functions in the yolk cell to regulate epiboly. We positionally cloned the bbp mutant gene and identified it as the serine-threonine kinase Mitogen Activated Protein Kinase Activated Protein Kinase 2, or MAPKAPK2, which was not previously known to function in embryonic development. We show that the regulation of MAPKAPK2 is conserved within a p38 MAP kinase pathway, thus identifying a new pathway in the regulation of this fundamental cell movement process. We postulate that a p38 MAPKAPK2 kinase cascade modulates F-actin contraction at the yolk cell margin circumference, allowing the gradual closure of the cells over the yolk cell as epiboly progresses.
PMCID: PMC2652113  PMID: 19282986
Objective: To evaluate the accuracy of a scoring system combining zygote and embryo morphology in predicting the outcome of in vitro fertilization (IVF) treatment. Methods: In a study group, 117 consecutive IVF or intracytoplasmic sperm injection (ICSI) cycles with embryo transfer were carried out and 312 embryos were scored using a combined scoring system (CSS) of zygote and embryo morphology before transplantation. In a control group, a total of 420 IVF or ICSI cycles were carried out and 1176 embryos were scored using a cumulative embryo score (CES). The effects of the combined scoring system on the embryo implantation rate and pregnancy rate per cycle were analyzed. Results: Using the combined scoring system, the embryo implantation rate (27.6%) and the clinical pregnancy rate (48.7%) were significantly higher than those in the control group (20.8% and 38.6%, respectively). Also, the implantation rate of embryos scoring ≥70 (38.5%: 82 sacs/213 embryos) was significantly higher (P<0.001) than that of embryos scoring <70 (4%: 4 sacs/99 embryos). The pregnancy rate of patients with embryos scoring ≥70 using the combined scoring system (66.7%) was significantly higher (P<0.001) than that of patients with embryos scoring ≥20 using the cumulative embryo score (59.0%). Conclusion: The results suggest that selecting embryos with a high score (≥70) using the combined scoring system could increase the implantation rate and pregnancy rate, and that using a scoring system combining assessments of human zygotes and pre-implantation embryos might predict IVF outcomes more accurately than using a cumulative embryo score.
PMCID: PMC2491695  PMID: 18763315
Embryo score; Combined scoring system (CSS); Implantation; In vitro fertilization (IVF); Pregnancy
AIM: To investigate the effect of omega-3 fatty acid parenteral supplementation postoperatively on clinical outcomes and immunomodulation in colorectal cancer patients.
METHODS: Forty-two patients undergoing radical colorectal cancer resection with an indication for total parenteral nutrition postoperatively were enrolled in this prospective, double-blind, randomized, controlled study. Patients received total parenteral nutrition supplemented with either soybean oil (LCT; Intralipid®, Fresenius-Kabi, SO group, n = 21) or a combination of omega-3 fish oil and soybean oil (LCT:fish oil = 5:1, fish oil; Omegaven®, Fresenius-Kabi, FO group, n = 21), up to a total of 1.2 g lipid/kg per day for 7 d postoperatively. A same volume calorie and nitrogen was administrated. Routine blood test, biochemistry, systemic levels of IL-6 and TNF-α, percentage of CD3+, CD4+, and CD8+ lymphocytes were evaluated preoperatively and on postoperative d 1 and 8. Patient outcome was evaluated considering mortality during the hospital stay, length of postoperative hospital stay, and occurrence of infectious complications.
RESULTS: Both lipid regimens were well tolerated. No differences between the two groups were noticed in demographics, baseline blood test, biochemistry, serum levels of IL-6 and TNF-α, percentage of CD4+, CD8+ lymphocytes, and ratios of CD4+/CD8+. Compared with those on postoperative d 1, serum IL-6 levels on postoperative d 8 were significantly depressed in the FO group than in the reference group (-44.43 ± 30.53 vs -8.39 ± 69.08, P = 0.039). Simultaneously, the ratios of CD4+/CD8+ were significantly increased in the FO group (0.92 ± 0.62 vs 0.25 ± 1.22, P = 0.035). In addition, depression of serum TNF-α levels (-0.82 ± 2.71 vs 0.27 ± 1.67, P = 0.125) and elevation of CD3+ and CD4+ lymphocyte percentage (12.85 ± 11.61 vs 3.84 ± 19.62, P = 0.081, 17.80 ± 10.86 vs 9.66 ± 17.55, P = 0.084, respectively) were higher in the FO group than in the reference group. Patients in the FO group trended to need a shorter postoperative hospital stay (17.45 ± 4.80 d vs 19.62 ± 5.59 d, P = 0.19). No statistically significant difference was found when stratified to mortality and occurrence of infectious complications.
CONCLUSION: Postoperative supplementation of omega-3 fatty acids may have a favorable effect on the outcomes in colorectal cancer patients undergoing radical resection by lowering the magnitude of inflammatory responses and modulating the immune response.
PMCID: PMC2705104  PMID: 18416476
Colorectal cancer; Parenteral nutrition; Omega-3 fatty acids; Immunomodulation; Abdominal surgery
BMC Bioinformatics  2006;7:25.
A variety of diseases are caused by chromosomal abnormalities such as aneuploidies (having an abnormal number of chromosomes), microdeletions, microduplications, and uniparental disomy. High density single nucleotide polymorphism (SNP) microarrays provide information on chromosomal copy number changes, as well as genotype (heterozygosity and homozygosity). SNP array studies generate multiple types of data for each SNP site, some with more than 100,000 SNPs represented on each array. The identification of different classes of anomalies within SNP data has been challenging.
We have developed SNPscan, a web-accessible tool to analyze and visualize high density SNP data. It enables researchers (1) to visually and quantitatively assess the quality of user-generated SNP data relative to a benchmark data set derived from a control population, (2) to display SNP intensity and allelic call data in order to detect chromosomal copy number anomalies (duplications and deletions), (3) to display uniparental isodisomy based on loss of heterozygosity (LOH) across genomic regions, (4) to compare paired samples (e.g. tumor and normal), and (5) to generate a file type for viewing SNP data in the University of California, Santa Cruz (UCSC) Human Genome Browser. SNPscan accepts data exported from Affymetrix Copy Number Analysis Tool as its input. We validated SNPscan using data generated from patients with known deletions, duplications, and uniparental disomy. We also inspected previously generated SNP data from 90 apparently normal individuals from the Centre d'Étude du Polymorphisme Humain (CEPH) collection, and identified three cases of uniparental isodisomy, four females having an apparently mosaic X chromosome, two mislabelled SNP data sets, and one microdeletion on chromosome 2 with mosaicism from an apparently normal female. These previously unrecognized abnormalities were all detected using SNPscan. The microdeletion was independently confirmed by fluorescence in situ hybridization, and a region of homozygosity in a UPD case was confirmed by sequencing of genomic DNA.
SNPscan is useful to identify chromosomal abnormalities based on SNP intensity (such as chromosomal copy number changes) and heterozygosity data (including regions of LOH and some cases of UPD). The program and source code are available at the SNPscan website .
PMCID: PMC1382255  PMID: 16420694
Retrovirology  2005;2:63.
HIV-1 and all retroviruses are related to retroelements of simpler organisms such as the yeast Ty elements. Recent work has suggested that the yeast retroelement Ty1 replicates via an unexpected RNA lariat intermediate in cDNA synthesis. The putative genomic RNA lariat intermediate is formed by a 2'-5' phosphodiester bond, like that found in pre-mRNA intron lariats and it facilitates the minus-strand template switch during cDNA synthesis. We hypothesized that HIV-1 might also form a genomic RNA lariat and therefore that siRNA-mediated inhibition of expression of the human RNA lariat de-branching enzyme (DBR1) expression would specifically inhibit HIV-1 replication.
We designed three short interfering RNA (siRNA) molecules targeting DBR1, which were capable of reducing DBR1 mRNA expression by 80% and did not significantly affect cell viability. We assessed HIV-1 replication in the presence of DBR1 siRNA and found that DBR1 knockdown led to decreases in viral cDNA and protein production. These effects could be reversed by cotransfection of a DBR1 cDNA indicating that the inhibition of HIV-1 replication was a specific effect of DBR1 underexpression.
These data suggest that DBR1 function may be needed to debranch a putative HIV-1 genomic RNA lariat prior to completion of reverse transcription.
PMCID: PMC1266399  PMID: 16232320

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