Catalytic helix-sense-selective polymerisation of achiral substituted acetylenes containing bulky π-conjugated planar substituents yielding soluble and statically stable one-handed helical polymers

Helix-sense-selective polymerisation of three new achiral substituted acetylenes containing two bulky π-conjugated planar substituents via imino groups by using catalytic amounts of a chiral source were achieved.

Correlation between MTP -493G>T polymorphism and non-alcoholic fatty liver disease risk: a meta-analysis

Several studies have found that microsomal transfer protein (MTP) may be important in the development and progression of non-alcoholic fatty liver disease (NAFLD). In this meta-analysis, we evaluated the relationships between a common polymorphism (-493G>T, rs1800591 G>T) in the MTP gene and NAFLD risk. The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases were searched for relevant articles published before October 1, 2013 without any language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated. Eleven case-control studies were included in this meta-analysis. A total of 636 NAFLD patients and 918 healthy control subjects were examined in this meta-analysis. Our results indicate that the MTP -493G/T polymorphism increases the risk of NAFLD (G allele vs T allele: OR = 1.39, 95%CI = 1.17-1.65, P < 0.001; GG + GT vs TT: OR = 1.46, 95%CI = 1.02-2.09, P = 0.038, respectively). Subgroup analyses indicated that the MTP -493G/T polymorphism was associated with an increased risk of NAFLD in population-based, hospital-based, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and large sample-size subgroups under the allele and dominant models (all P < 0.05). However, we found no association between non-PCR-RFLP polymorphism and small sample-size subgroups (all P > 0.05). Our findings indicate that the MTP -493G/ T polymorphism may contribute to the development of NAFLD. Thus, the MTP -493G/T polymorphism may be a biomarker for the early detection of NAFLD.

PUMA is invovled in ischemia/reperfusion-induced apoptosis of mouse cerebral astrocytes

PUMA (p53-upregulated modulator of apoptosis), a BH3-only member of the Bcl-2 protein family, is required for p53-dependent and p53-independent forms of apoptosis. PUMA has been invovled in the onset and progress of several diseases, including cancer, acquired immunodeficiency syndrome, and ischemic brain disease. Although many studies have shown that ischemia and reperfusion (I/R) can induce the apoptosis of astrocytes, the role of PUMA in I/R-mediated apoptosis of cerebral astrocyte apoptosis remains unclear. To mimic in vivo I/R conditions, primary mouse cerebral astrocytes were incubated in a combinational cultural condition of oxygen, glucose, and serum deprivation (OSGD) for 1 h followed by reperfusion (OSGD/R). Cell death determination assays and cell viability assays indicated that OSGD and OSGD/R induce the apoptosis of primary cerebral astrocytes. The expression of PUMA was significantly elevated in primary cerebral astrocytes during OSGD/R. Moreover, targeted down-regulation of PUMA by siRNA transfection significantly decreased the OSGD/R-induced apoptosis of primary cerebral astrocytes. We also found that OSGD and OSGD/R triggered the release of cytochrome c in astrocytes, indicating the dependence on a mitochondrial apoptotic pathway. Reactive oxygen species (ROS) was extremely generated during OSGD and OSGD/R, and the elimination of ROS by treated with N-acetyl-L-cysteine (NAC) remarkably inhibited the expression of PUMA and the apoptosis of primary cerebral astrocytes. The activation of Caspase 3 and Caspase 9 was extremely elevated in primary cerebral astrocytes during OSGD. In addition, we found that knockdown of PUMA led to the depressed expression of Bax, cleaved caspase-9 and caspase-3 during OSGD/R. These results indicate that PUMA is invovled in the apoptosis of cerebral astrocytes upon I/R injury.

First Report of Fusarium equiseti Causing a Sheath Rot of Corn in China

Corn is the most important cereal crop in China. Over 34.94 million ha of corn is cultivated in the country annually. However, fungal diseases are a major limiting factor in corn production. In August 2008, 50 ha in several corn fields in Liaoning, Jilin, and Heilongjiang provinces were observed to be severely affected by a disease causing a yield loss of 30%. Results from field surveys suggested an epidemic during late corn growth stages that affected corn sheaths, causing irregularly circular spots with grayish brown to dark brown lesions. Lesions ranged from 2.5 to 3 × 3 to 5 cm. To isolate the causal agent, tissue was removed from the border of lesions and surface sterilized in 75% ethanol for 30 sec and 0.1% HgCl₂ for 1 min. The sample was then triple rinsed in sterile distilled water. The isolate was purified and subcultured on potato dextrose agar (PDA) at 25 ± 2°C. The initial color of the mycelium was white, turning brown after being cultured for 7 days. A pale brown to dark brown pigment developed in the agar beneath the colony. Chlamydospores, solitary but also in short chains, measuring 7.2 to 15.3 μm, were produced on carnation leaf agar (CLA) after 10 days and became verrucose 20 days later. Macroconidia were produced on CLA in orange sporodochia from monophialides on branched conidiophores, usually 5- to 7-septate, and apical cells were tapered and elongate. Basal cells were prominent, foot-shaped, and elongated in appearance. Microconidia were not observed (1). These morphological characteristics matched the description of Fusarium equiseti reported by Leslie and Summerell (1). A pathogenicity test was conducted with an isolate from each of the 36 corn plants by spraying 2 ml of spore suspension (10⁶ conidia/ml) on 45-day-old corn sheaths (cv. Huang Zao). For the control treatment, 36 corn plants were sprayed with an equal volume of sterilized water. Inoculated plants were placed in a greenhouse at 32 to 34°C and 95% relative humidity. Typical irregularly circular lesions were observed 7 days after inoculation, except in the control samples. Each treatment was replicated three times. The suspected pathogen was consistently re-isolated from diseased tissue according to Koch's postulates, and was found to be morphologically similar to F. equiseti. Preliminary morphological identification of the fungus was confirmed by a PCR assay using genomic DNA extracted from the mycelia of a 7-day-old culture on PDA at 25 ± 2°C. A 750-bp amplified region of the transcription elongation factor (TEF) of rDNA was generated using TEF1 (5'-ATGGGTAAGGAGGACAAGAC-3') and TEF2 (5'-GGAAGTACCAGTGATCATGTT-3') primers. The TEF region (GenBank Accession No. KF754798) was sequenced by Sangon Biotech Co., Ltd. (Shanghai, China) and displayed 99% nucleotide similarity with the rDNA-TEF of F. equiseti (JN127347.1) separately after a BLASTn search in GenBank. Based on the symptoms, fungal morphology, TEF sequence, and pathogenicity testing, this fungus was identified as F. equiseti. To our knowledge, this is the first report of F. equiseti on corn sheaths in China. This report will establish a foundation for further study of F. equiseti to address the disease effectively and to determine the severity of damage caused by F. equiseti. Reference: (1) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell, Ames, IA, 2006.

Molecular imaging of σ1 receptors in vivo: current status and perspectives

It is widely accepted that sigma (σ) receptors represent a new and different avenue in the possible pharmacological treatment of cancer and several brain-related disorders. Of the two different σ receptor types the σ1 receptors are assumed to be of major impact for brain diseases. Molecular imaging of brain σ1 receptors with positron emission tomography (PET) or single photon emission computed tomography (SPECT) may provide a significant contribution to the understanding of the cross-talk between σ1 receptors and inter- and intracellular signalling systems. New insights into these functional interrelationships will allow a better diagnosis of brain and cancerous diseases and direct a rational development of new therapeutic concepts.

Studying the association of microRNA-210 level with chronic hepatitis B progression

We studied the relationship between hypoxia and microRNA-210 (miR-210) levels, the miR-210 levels in patients with hepatitis B and the roles of miR-210 in liver inflammation. We used the concanavalin A (Con A) murine hepatitis model and inflammation, hypoxia and miR-210 levels were examined. In these patients, we studied serum miR-210 levels and clinical indexes related to hepatitis in 90 patients with different stages of chronic hepatitis B and 30 controls. Two functional assays of miR-210 in vitro under hypoxic condition were conducted. The animal experiments indicated that the liver and serum miR-210 levels significantly increased with liver hypoxia and inflammation. In humans, serum miR-210 levels enhanced with hepatitis severity and were related to serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB) and prothrombin activity (PTA) levels. The miR-210 functional assays showed that miR-210 elevation might be related to the decreases in HepG2.2.15 cell dehydrogenase activity and HBV replication under hypoxic conditions. Because the liver inflammation causes liver hypoxia which also results in liver and serum miR-210 level elevation, the serum miR-210 level may serve as a molecular biomarker for the severity of hepatitis and increases in liver miR-210 that we see may be a response of hepatocytes to hypoxia during hepatitis progression.

Atorvastatin suppresses Toll-like receptor 4 expression and NF-κB activation in rabbit atherosclerotic plaques

BACKGROUND

Toll-like receptor 4 (TLR4) plays an essential role in the pathogenesis and progression of atherosclerosis, which overexpresses in atherosclerotic lesions and mediates the production of inflammatory factors. The aim of this study was to investigate the effects of atorvastatin on TLR4 protein and mRNA expression and its downstream factor NF-κB activation in rabbit atherosclerotic plaques.

MATERIALS AND METHODS

Rabbits continuously fed with high-fat diet for 24 weeks were randomly divided into two groups, the drug-treated group orally administrated with atorvastatin (2 mg/kg/day) three weeks after high-fat diet feeding and the model group with no treatment. The expression of TLR4 protein and mRNA, the level of activated NF-κB (p65) were respectively detected by western blotting, quantitative RT-PCR, and ELISA.

RESULTS

The results showed that atorvastatin treatment reduced the expression of TLR4 protein and mRNA by 24.1% (p < 0.05) and 46.9% (p < 0.01), respectively, and also inhibited NF-κB activation by 76.0% (p < 0.001) in the atherosclerotic plaques.

CONCLUSIONS

Thus, it was suggested that atorvastatin could exert an anti-atherosclerotic activity besides inhibiting cholesterol biosynthesis.

Cognitive trio: relationship with major depression and clinical predictors in Han Chinese women

BACKGROUND

Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.

METHOD

The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.

RESULTS

Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.

CONCLUSIONS

During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.

First Report of Bipolaris papendorfii Causing Corn Leaf Spot in China

Corn is the most important cereal crop in China, with over 34.94 million ha being cultivated in the country annually. However, fungal diseases are a major limiting factor in corn production. In August 2012, 20 ha of corn fields in Anhui Province were found to be heavily infected by fungi. The margin of the lesion was achlorotic, and the middle was yellowish white or off-white, which was similar to the corn Curvalaria leaf spot. The oval lesions were approximately 5 to 7 mm. Lesion tissue was removed from the border between symptomatic and healthy tissue. The surface was sterilized in 75% ethanol for 30 s and 0.1% HgCl₂ for 1 min, after which the sample was washed three times in sterile distilled water. The isolate was purified and subcultured on potato dextrose agar (PDA) at 25 ± 2°C. The initial color of the colony was light brown, turning dark brown after being cultured for 7 days. The conidia were boat-shaped or inverted pear-shaped and were clearly bent to one side. The cells of both ends were slightly lighter and respectively ranged from 34.5 to 44.0 μm and 12.0 to 21.0 μm away from the base, with the second cell as the widest. The majority conidia had three or four false septates; isolates produced light brown to medium brown conidiophore, scattered or clustered, often branching, and exhibited bending. These morphological characteristics matched with the description of Bipolaris papendorfii reported by Zhang (3). A pathogenicity test was conducted with the two isolates on each of the 36 corns by spraying 2 ml spore suspension (10⁶ conidia/ml). For the control treatment, 36 corns were inoculated with an equal volume of sterilized water. Inoculated plants were placed in a greenhouse from 29 to 33°C and 95% relative humidity. The typical 5 to 7 mm oval lesions were observed 7 days after inoculation, except on the control samples. Three replications of 36 corns were used for each treatment. The isolate was consistently 100% reisolated from the diseased tissue according to Koch's postulate. The isolate was found to be morphologically similar to B. papendorfii. Preliminary morphological identification of the fungus was confirmed by PCR assay using genomic DNA extracted from the mycelium of a 7-day-old culture on PDA at 25 ± 2°C. A 550-bp amplified region of the internal transcribed spacer (ITS) of rDNA was generated using ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3') universal primers (1). The ITS region (GenBank Accession No. KC592365) was then sequenced by Sangon Biotech (Shanghai, China), and displayed 99% nucleotide similarity with the rDNA-ITS of B. papendorfii (JQ753972.1) separately after BLASTn research in GenBank. Based on the symptoms, fungal morphology, ITS sequence, and pathogenicity testing, this fungus was identified as B. papendorfii. The pathogen could reportedly infect tobacco and cotton (2). To our knowledge, this is the first study to report that B. papendorfii can infect corn in China. This report will establish a foundation for the further study of B. papendorfii to address the disease effectively. Further studies will be conducted to determine the incidence of the disease and the severity of damage caused by B. papendorfii as well as determine a possible mode for controlling the spread of the disease. References: (1) Y. J. Cao et al. Chin. J. Trop. Crops 31:1098, 2010. (2) H. Deng et al. Mycosystema 21:327, 2002. (3) T. Y. Zhang. Chin. Fungi Chi. 30:21, 2010.

Prevalence of high-risk human papilloma virus among women with hepatitis C virus before liver transplantation

BACKGROUND

We sought to assess the prevalence and risk factors for high-risk human papillomavirus (HPV) infection among female liver transplant (LT) candidates. Traditional health screening before LT listing has included Pap smear and is typically carried out by the patient's local provider. The prevalence of high-risk HPV in this population has not been studied.

METHODS

With Institutional Review Board approval, 62 LT candidates received a liquid-based Pap smear with high-risk HPV testing as part of their pre-transplant evaluation by a single provider. Clinical variables included age, ethnicity, insurance status, prior Pap smear, and HPV results, HPV risk factors including age of first intercourse, number of lifetime partners, last sexual activity, smoking, birth control pill use, history of sexually transmitted infections, human immunodeficiency virus status, immunosuppressive medication, medical diagnoses, prescribed medications, and history of hepatitis A, B, C, or D.

RESULTS

The 62 women had a median age of 56 years, and 39% had high-risk behavior known to be associated with HPV. Ten of 62 patients (16.1%) had high-risk HPV at baseline screening, 5 of whom had atypical cytology. All of the patients who were positive for high-risk HPV had an etiology of hepatitis C virus (HCV) as the underlying cause of liver disease, with the majority (90%) having no history of high-risk behavior for HPV. In contrast, all patients with high-risk behavior who were HCV negative were HPV negative. Fisher's exact test demonstrated a statistically significant relationship between HPV and HCV; odds ratio = 24.4, 95% confidence interval, 1.4, 438.7, P-value = 0.0013. None of the other potential risk factors were associated with HPV in this cohort.

CONCLUSIONS

In this study, we provide evidence of a strong association between HCV and HPV in LT candidates, which has not been previously reported. HPV positivity was observed in non-sexually active women, suggesting a reactivation of dormant HPV. An association between hepatitis C and high-risk HPV could involve impairment of T-cell function by hepatitis C. These data support close surveillance in women's health screening for LT candidates. Further studies to characterize immune responses in these patients will be in order.

Targeted therapy via oral administration of attenuated Salmonella expression plasmid-vectored Stat3-shRNA cures orthotopically transplanted mouse HCC

The development of RNA interference-based cancer gene therapies has been delayed due to the lack of effective tumor-targeting delivery systems. Attenuated Salmonella enterica serovar Typhimurium (S. Typhimurium) has a natural tropism for solid tumors. We report here the use of attenuated S. Typhimurium as a vector to deliver shRNA directly into tumor cells. Constitutively activated signal transducer and activator of transcription 3 (Stat3) is a key transcription factor involved in both hepatocellular carcinoma (HCC) growth and metastasis. In this study, attenuated S. Typhimurium was capable of delivering shRNA-expressing vectors to the targeted cancer cells and inducing RNA interference in vivo. More importantly, a single oral dose of attenuated S. Typhimurium carrying shRNA-expressing vectors targeting Stat3 induced remarkably delayed and reduced HCC (in 70% of mice). Cancer in these cured mice did not recur over 2 years following treatment. These data demonstrated that RNA interference combined with Salmonella as a delivery system may offer a novel clinical approach for cancer gene therapy.

An oncogenic role of miR-142-3p in human T-cell acute lymphoblastic leukemia (T-ALL) by targeting glucocorticoid receptor-α and cAMP/PKA pathways

MicroRNAs (miRNAs) are a family of 19-24 nucleotide non-coding RNAs with posttranscriptional regulatory functions. The involvement of miRNAs in normal hematopoiesis implies that deregulated miRNAs might contribute to leukemogenesis. To date, although certain miRNAs have been established a clear oncogenic role in hematological malignancies, other individual miRNAs potentially involved in human leukemogenesis still remain elusive. In this report, we showed that miR-142-3p was upregulated in human T-leukemic cell lines and primary T-leukemic cells isolated from T-cell acute lymphoblastic leukemia (T-ALL) patients and its expressive levels were correlated with patients' prognosis. Such an oncogenic role of miR-142-3p could be explained by its targeting cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) and glucocorticoid receptor alpha (GRα). High levels of miR-142-3p resulted in low levels of cAMP and weak activity of PKA, thus relieving the inhibitory effect of PKA on T-leukemic cell proliferation. Meanwhile, miR-142-3p decreased GRα protein expression by directly targeting the 3'-untranslational region of GRα mRNA, leading to glucocorticoid resistance. Transfection of the miR-142-3p inhibitor effectively converted glucocorticoid resistance, because of the resultant increase of GRα expression and PKA activity. These findings suggest that miR-142-3p is critical in T-cell leukemogenesis and may serve as a potential therapeutic target in T-ALL patients.