[The accuracy of mammography screening for breast cancer: a Meta-analysis]

Objective: To estimate the accuracy of mammography for population-based breast cancer screening. Methods: Studies of screening mammography performance were systematically reviewed in the Medline, Embase, Cochrane and China National Knowledge Infrastructure (CNKI) literature databases. The retrieval was performed by using related key words, including disease name, screening and intervention indicators and study type. A total of 1 167 records were retrieved by June 4, 2015 and those studies met the inclusion criteria were included for the current analysis. The numbers of true-positive, false-positive, false-negative and true-negative were originally extracted and calculated from each individual study. A QUADAS checklist was used to assess the quality of the studies. A curve of summary receiver operating characteristic (SROC) was applied as a comprehensive assessment of diagnosed accuracy. The pooled effect size of both sensitivity and specificity was quantitatively synthesized in both total population and subgroup with dense breast using the bivariate mixed-effects models. We conducted a sensitivity analysis in the studies with sample size over 100 000. Heterogeneity between studies was measured by the Q test and I² statistic, and publication bias was evaluated by a funnel plot and the linear regression test. Results: A total of 48 publications with 8 551 873 individuals were identified for the final qualitative synthesis, most of them were from Europe area and American (38 studies), 8 were from Asia area, and 2 were from Oceania area. The studies were conducted during period of 1975-2013, and the age of study women ranged mostly from 40 to 75 years. The area under the SROC curve (AUC) was 0.95 (95%CI: 0.93-0.97). It was estimated that the pooled sensitivity and specificity were 0.81 (95%CI: 0.77-0.84) and 0.96 (95%CI: 0.94-0.96), respectively. The results were indicated stable and robust in sensitivity analysis. In the subgroup with dense breast, the sensitivity and specificity were 0.74 (95% CI: 0.61-0.83) and 0.93 (95% CI: 0.89-0.96), respectively. Funnel plot and test results showed there was no significant publication bias among the included studies. Conclusion: The accuracy of mammography is high for population-based breast cancer screening in women, although the sensitivity is lower in women with dense breast.

Oral health impact of halitosis in Chinese adults

OBJECTIVES

To compare differences in oral health-related quality of life (OHRQoL) between halitosis and non-halitosis patients and to explore relationships between halitosis and OHRQoL.

METHODS

Patients who visited the halitosis clinic at the Ninth People's Hospital and were diagnosed with halitosis were included in the halitosis group. The control group consisted of patients without halitosis. All participants were assessed for halitosis (volatile sulphur compound measurements with a portable sulphide monitor, Oral Chroma and organoleptic tests), underwent a clinical oral examination (dental caries status and periodontal condition) and completed a questionnaire. Oral health-related quality of life was measured using the Oral Health Impact Profile (OHIP-14, Chinese version).

RESULTS

A total of 204 patients (102 halitosis and 102 controls) were included. The halitosis group had significantly higher OHIP-14 scores (severity) than the control group (15.7 versus 7.9, P < 0.001). The mean number of items with negative impact (extent) was significantly different between the halitosis and control groups (1.8 versus 0.3, P < 0.001). Around 56% of participants in the halitosis group reported at least one item with 'fairly often' or 'very often' (prevalence), while 21% did so in the control group (P < 0.001). In halitosis patients, the most commonly reported negative impacts were within the domains of 'psychological discomfort' and 'psychological disability'.

CONCLUSIONS

Oral health-related quality of life status was significantly poorer in halitosis patients than in non-halitosis patients. Halitosis patients may experience some degree of psychological discomfort and disability.

Control Release Anesthetics to Enable an Integrated Anesthetic-mesenchymal Stromal Cell Therapeutic

While general anesthetics control pain via consciousness regulation, local anesthetics (LAs) act by decreasing sensation in the localized area of administration by blocking nerve transmission to pain centers. Perioperative intra-articular administration of LAs is a commonly employed practice in orthopedic procedures to minimize patient surgical and post-surgical pain and discomfort. LAs are also co-administered with cellular mesenchymal stromal cell (MSC) therapies for a variety of tissue regenerative and inflammatory applications including osteoarthritis (OA) treatment; however, LAs can affect MSC viability and function. Therefore, finding an improved method to co-administer LAs with cells has become critically important. We have developed a sustained release LA delivery model that could enable the co-administration of LAs and MSCs. Encapsulation of liposomes within an alginate matrix leads to sustained release of bupivacaine as compared to bupivacaine-containing liposomes alone. Furthermore, drug release is maintained for a minimum of 4 days and the alginate-liposome capsules mitigated the adverse effects of bupivacaine on MSC viability.

Abnormal Patella Height Based on Insall-Salvati Ratio and its Correlation with Patellar Cartilage Lesions: An Extremity-Dedicated Low-Field Magnetic Resonance Imaging Analysis of 1703 Chinese Cases

Background and aims:

Diagnostic performance of patellar position for patellar cartilage lesions remains unclear. The aim of this study was to assess the abnormal patella height and its correlation with chondral lesions of the patellofemoral joint in China.

Material and methods:

A total of 1703 consecutive patients who performed knee joint examination using an extremity-dedicated low-field magnetic resonance imaging were enrolled in this study. Patellar cartilage lesions were diagnosed based on the result of magnetic resonance imaging and clinical data. Patella height was defined as the ratio of patellar tendon length to patellar length according to Insall-Salvati index. Patella alta and infera were defined as tendon length/patellar length >1.2 and <0.8, respectively.

Results:

The total prevalence of patellar cartilage lesions was 38.0%. The prevalence in females was significantly higher than that in males (46.4% vs 28.8%, p < 0.001). Age notably increased the incidence of patellar cartilage lesions ( p < 0.001). Logistic regression analysis showed that tendon length/patellar length ratio was significantly correlated with patellar cartilage lesions (odds ratio = 6.380, p < 0.001). Furthermore, patients with cartilage lesions showed significantly higher rates of patella alta and infera ( p < 0.001). In addition, receiver operating characteristic curve analysis demonstrated that abnormal patella height had statistical significance in diagnosing cartilage lesions ( p < 0.001). However, the area under the curve (0.596; 95% confidence interval: 0.568–0.624) and sensitivity (47.0%) were relatively low, while the specificity was 72.2%.

Conclusions:

Patients with patellar cartilage lesions have an increased tendon length/patellar length ratio. The abnormal patella height is significantly correlated with chondral lesions and can be used as a potential diagnostic marker.

Correlation between protein 4.1R and the progression of heart failure in vivo

We aimed to assess the protein 4.1R (4.1R) expression of the membrane skeleton in cardiomyocytes and to determine the potential role of 4.1R in the pathogenesis of heart failure (HF). Forty-two male mice were randomly divided into two groups: an HF group (N = 22) and control group (N = 20). The HF model was established by abdominal subcutaneous injection of 5 mg⋅kg(-1)⋅day(-1) isopropyl adrenaline to the mice for 14 days. Electrocardiography was carried out and cardiac function was assessed by ultrasonic cardiogram. The left ventricular weight index (LVMI) was measured after mice were sacrificed, and the pathological changes of the heart were observed by hematoxylin and eosin staining. The expression of 4.1R in cardiomyocytes was analyzed by immunohistochemistry, immunofluorescence, and reverse transcription polymerase chain reaction. The echocardiographs showed that the left ventricular end-diastolic dimension (LVEDD) and left ventricular end-systolic dimension (LVESD) were significantly higher in the HF group than in the controls (P < 0.05), while the left ventricle shortening fraction was remarkably lower than that in the controls (P < 0.05). Electrocardiography showed faster heart rates in the HF group than in the control group (P < 0.05). Both the LVMI and the myocardial tissue pathological score were significantly higher (P < 0.01) in the HF group than in the controls. 4.1R localized mostly to the plasma membrane and was distributed discretely in the cytosol of myocardial cells. The proportion of 4.1R-positive cells was significantly higher in the HF group (P < 0.01) than in the controls, which was confirmed by the positive mRNA expression of 4.1R. 4.1R localized mostly to the plasma membrane of myocardial cells and was upregulated with the progression of HF. This suggests that 4.1R may be associated with HF progression and therefore 4.1R represents a promising therapeutic target in HF.

Determinants of Gefitinib toxicity in advanced non-small cell lung cancer (NSCLC): a pharmacogenomic study of metabolic enzymes and transporters

Skin rash, diarrhea and hepatotoxicity are the most common toxicities of Gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. The present study investigated the effects of genetic polymorphisms of drug target, metabolizing enzymes and transporters on Gefitinib toxicities. Thirty single-nucleotide polymorphisms, including EGFR, cytochromes P450 and ATP-binding cassette (ABC), were genotyped by matrix-assisted laser desorption/ionization time-of-flight platform in 59 non-small cell lung cancer patients treated with Gefitinib. Correlation analyses were performed to evaluate their effects on Gefitinib-induced toxicities. ABCB1 rs1128503 TT genotype was a significant high-risk determinant of both skin rash and diarrhea, with 15.78- and 10.78-fold of incident risk increased, respectively. (odds ratio (OR)=15.78, 95% confidence interval (CI) 2.01-124.1, P=0.0087; OR=10.78, 95% CI 1.54-75.40, P=0.0166 vs non-TT genotypes). Patients with ABCB1 rs1128503 TT genotype had greater risk of skin rash and diarrhea. Therefore, polymorphism analyses of ABCB1 might be beneficial to optimize Gefitinib treatment.

Hybridization chain reaction amplification for highly sensitive fluorescence detection of DNA with dextran coated microarrays

Microarrays of biomolecules hold great promise in the fields of genomics, proteomics, and clinical assays on account of their remarkably parallel and high-throughput assay capability. However, the fluorescence detection used in most conventional DNA microarrays is still limited by sensitivity. In this study, we have demonstrated a novel universal and highly sensitive platform for fluorescent detection of sequence specific DNA at the femtomolar level by combining dextran-coated microarrays with hybridization chain reaction (HCR) signal amplification. Three-dimensional dextran matrix was covalently coated on glass surface as the scaffold to immobilize DNA recognition probes to increase the surface binding capacity and accessibility. DNA nanowire tentacles were formed on the matrix surface for efficient signal amplification by capturing multiple fluorescent molecules in a highly ordered way. By quantifying microscopic fluorescent signals, the synergetic effects of dextran and HCR greatly improved sensitivity of DNA microarrays, with a detection limit of 10fM (1×10(5) molecules). This detection assay could recognize one-base mismatch with fluorescence signals dropped down to ~20%. This cost-effective microarray platform also worked well with samples in serum and thus shows great potential for clinical diagnosis.

Key KdSOC1 gene expression profiles during plantlet morphogenesis under hormone, photoperiod, and drought treatments

Kalanchoe daigremontiana utilizes plantlet formation between its zigzag leaf margins as its method of asexual reproduction. In this study, K. daigremontiana SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (KdSOC1), a key intermediate in the transition from vegetative to asexual growth, was cloned. Furthermore, its expression profiles during plantlet formation under different environmental and hormone induction conditions were analyzed. The full-KdSOC1 cDNA sequence length was 1410 bp with 70% shared homology with Carya cathayensis SOC1. The conserved domain search of KdSOC1 showed the absence of I and C domains, which might indicate novel biological functions in K. daigremontiana. The full-KdSOC1 promoter sequence was 1401 bp long and contained multiple-hormone-responsive cis-acting elements. Hormone induction assays showed that gibberellins and salicylic acid mainly regulated KdSOC1 expression. The swift change from low to high KdSOC1 expression levels during long-day induction was accompanied by the rapid emergence of plantlets. Drought stress stimulated KdSOC1 expression in leaves both with and without plantlet formation. Together, the results suggested that KdSOC1 was closely involved in environmental stimulation signal perception and the transduction of K. daigremontiana plantlet formation. Therefore, future identification of KdSOC1 functions might reveal key information that will help elucidate the transition network between embryogenesis and organogenesis during plantlet formation.

Association of COL4A1 gene polymorphisms with cerebral palsy in a Chinese Han population

The basement membrane (BM) is an extracellular matrix associated with overlying cells and is important for proper tissue development, stability, and physiology. COL4A1 is the most abundant component of type IV collagen in the BM, and COL4A1 variants can present with variable phenotypes that might be related to cerebral palsy (CP). We postulated, therefore, that variations in the COL4A1 gene might play an important role in the etiology of CP. In this study, six single nucleotide polymorphisms (SNPs) in the COL4A1 gene were genotyped among 351 CP patients and 220 healthy controls from the Chinese Han population. Significant association was found for an association between CP and rs1961495 (allele: p = 0.008, odds ratio (OR) = 1.387, 95% confidence interval (CI) = 1.088-1.767) and rs1411040 (allele: p = 0.009, OR = 1.746, 95% CI = 1.148-2.656) SNPs of the COL4A1 gene. Multifactor dimensionality reduction analysis suggested that these SNPs had interactive effects on the risk of CP. This study is the first attempt to investigate the contribution of polymorphisms in the COL4A1 gene to the susceptibility of CP in a Chinese Han population. This study shows an association of the COL4A1 gene with CP and suggests a potential role of COL4A1 in the pathogenesis of CP.

Spontaneous liquid crystal and ferromagnetic ordering of colloidal magnetic nanoplates

Ferrofluids are familiar as colloidal suspensions of ferromagnetic nanoparticles in aqueous or organic solvents. The dispersed particles are randomly oriented but their moments become aligned if a magnetic field is applied, producing a variety of exotic and useful magnetomechanical effects. A longstanding interest and challenge has been to make such suspensions macroscopically ferromagnetic, that is having uniform magnetic alignment in the absence of a field. Here we report a fluid suspension of magnetic nanoplates that spontaneously aligns into an equilibrium nematic liquid crystal phase that is also macroscopically ferromagnetic. Its zero-field magnetization produces distinctive magnetic self-interaction effects, including liquid crystal textures of fluid block domains arranged in closed flux loops, and makes this phase highly sensitive, with it dramatically changing shape even in the Earth's magnetic field.

Ferromagnetism has been known as a material property of solids since the time of the ancient Greeks. Here, Shuai et al. report that magnetic nanoplates suspended in a simple solvent can spontaneously align to form a ferromagnetic liquid, capable of both producing and sensing magnetic fields.

Adolescent exposure to cocaine increases anxiety-like behavior and induces morphologic and neurochemical changes in the hippocampus of adult rats

Repeated exposure to cocaine during adolescence may affect both physical and psychological conditions in the brain, and increase the risk of psychiatric disorders and addiction behaviors in adulthood. Adolescence represents a critical development period for the hippocampus. Moreover, different regions of the hippocampus are involved in different functions. Dorsal hippocampus (dHP) has been implicated in learning and memory, whereas ventral hippocampus (vHP) plays an important role in emotional processing. In this study, the rats that were exposed to cocaine during adolescence (postnatal days, P28-P42) showed higher anxiety-like behavior in the elevated plus maze test in adulthood (P80), but displayed normal spatial learning and memory in the Morris water maze test. Furthermore, repeated exposure to cocaine during adolescence lead to alterations in morphology of pyramidal neurons, activities of astrocytes, and levels of proteins that involved in synaptic transmission, apoptosis, inflammation and addiction in both dHP and vHP of adult rats. These findings suggest that repeated exposure to cocaine during adolescence in rats may elicit morphologic and neurochemical changes in the hippocampus when the animals reach adulthood. These changes may contribute to the increased susceptibility for psychiatric disorders and addiction seen in adults.

Lentivirus-mediated RNA interference of myostatin gene affects MyoD and Myf5 gene expression in duck embryonic myoblasts

The aim of this study was to construct lentivirus-mediated short hairpin RNA (shRNA) vectors targeting the duck MSTN gene and investigate whether these vectors can affect the development of duck primary cultured embryonic myoblasts. MSTN mRNA levels in the myoblasts were detected using quantitative real-time polymerase chain reaction (PCR), cell proliferation was assessed by MTT assays and cell differentiation was assayed by photography. MSTN mRNA levels in PLL3.7-MSTN-shRNA1, PLL3.7-MSTN-shRNA2 and PLL3.7-MSTN-shRNA3 lentivirus-mediated shRNA groups were reduced by 61.6%, 76.9% and 79.1%, respectively, compared to control cells. Down-regulation of MSTN in duck embryonic myoblasts stimulated cell proliferation and inhibited differentiation, accompanied by a greater than twofold down-regulation of MyoD expression and up-regulation of Myf5 expression. These results revealed that silencing of MSTN changes the development of duck embryonic myoblasts by regulating the expression level of MyoD and Myf5 genes.

1,25(OH)2D3 downregulates the Toll-like receptor 4-mediated inflammatory pathway and ameliorates liver injury in diabetic rats

BACKGROUND

Fatty acid deposition in the liver can activate a number of pro-inflammatory signaling pathways such as the Toll-like receptor 4 (TLR4) pathway, which may be important in the pathogenesis of nonalcoholic steatohepatitis. 1,25(OH)2D3 downregulates the expression of TLR4 and may represent a novel treatment strategy for reducing hepatocyte injury. Therefore, in this study, we investigated the protective effects of 1,25(OH)2D3 on diabetic liver injury in vivo.

METHODS

Streptozotocin (STZ)-induced diabetic rats were randomly divided into five groups and treated with low-dose 1,25(OH)2D3 (0.025 μg/kg/day), medium-dose 1,25(OH)2D3 (0.15 μg/kg/day), high-dose 1,25(OH)2D3 (0.3 μg/kg/day), insulin (protamine zinc insulin 16 U/kg/day, subcutaneous injection), or no intervention (the control group). Sixteen weeks later, the rats were killed, and blood samples were obtained to test lipid profiles and hepatic function. The infiltration of inflammatory cells, the level of fibrosis, and the expression levels of TLR4, nuclear factor-kappa B (NF-κB), and tumor necrosis factor-α (TNF-α) in the liver were analyzed. The hepatocytes were treated with vehicle control, LPS (100 ng), high fat [DMEM + FFA (0.1 mM: palmitic acid, oleic acid, 1:2)], LPS + high fat, vehicle + 1,25(OH)2D3 (10(-7) M), LPS + 1,25(OH)2D3, high fat + 1,25(OH)2D3, or LPS + high fat + 1,25(OH)2D3. RNA and protein were extracted to detect the expression of TLR4 and downstream inflammatory factors such as NF-ΚB, TNF-α, and IL-6. Groups of data were compared by single factor variance analysis.

RESULTS

High-dose 1,25(OH)2D3 administration for 16 weeks downregulated the expression of TLR4, NF-κB, and TNF-α in the liver tissue of diabetic rats and attenuated hepatic inflammation and fibrosis, as shown by immunohistochemical staining, hematoxylin and eosin staining, Masson's trichrome staining, reverse transcription polymerase chain reaction (RT-PCR), and western blotting. In vitro, hepatocytes treated with high fat or LPS exhibited significantly increased expression of TLR4, NF-κB, and downstream inflammatory factors (P < 0.05). Intervention with 1,25(OH)2D3 decreased the expression of TLR4, NF-κB, and inflammatory factors (P < 0.05).

CONCLUSIONS

1,25(OH)2D3 exhibited protective effects against diabetes-related liver injury, possibly through downregulation of components of the TLR4 signaling pathway.

Identification of the microRNA expression profile in the regenerative neonatal mouse heart by deep sequencing

MicroRNAs (miRNAs) are small noncoding RNAs that are involved in key biological processes, including development, differentiation, and regeneration. The global miRNA expression profile that regulates the regenerative potential of the neonatal mouse heart has not been reported. We performed deep sequencing to determine the genome-wide miRNA expression profile of the neonatal mouse heart at three key ages (1, 6, and 7 days). The miRNAs at least 1.4-fold differentially expressed between the three time points were selected for further analysis. Two miRNAs (mmu-miR-22-5p and mmu-miR-338-3p) were significantly upregulated, and nine miRNAs (mmu-miR-324-5p, mmu-miR-337-5p, mmu-miR-339-5p, mmu-miR-365-1-5p, mmu-miR-500-3p, mmu-miR-505-5p, mmu-miR-542-5p, mmu-miR-668-3p, and mmu-miR-92a-1-5p) were significantly downregulated in cardiac tissue of 7-day-old mice compared to 1- and 6-day-old mice. The expression patterns of five significantly different miRNAs were verified by quantitative real-time PCR. Furthermore, the potential targets of these putative miRNAs were suggested using miRNA target prediction tools. The candidate target genes are involved in the myocardial regenerative process, with a prominent role for the Notch signaling pathway. Our study provides a valuable resource for future investigation of the biological function of miRNAs in heart regeneration.

17β-Estradiol up-regulates Nrf2 via PI3K/AKT and estrogen receptor signaling pathways to suppress light-induced degeneration in rat retina

Human age-related retinal diseases, such as age-related macular degeneration (AMD), are intimately associated with decreased tissue oxygenation and hypoxia. Different antioxidants have been investigated to reverse AMD. In the present study, we describe the antioxidant 17β-estradiol (βE2) and investigate its protective effects on retinal neurons. Fourteen days after ovariectomy, adult Sprague-Dawley rats were exposed to 8000-lux light for 12h to induce retinal degeneration. Reactive oxygen species (ROS) levels were assessed by confocal fluorescence microscopy using 2,7-dichlorofluorescein diacetate. Nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant enzyme mRNA expression were detected by real-time PCR. Western blotting was used to evaluate NRF2 activation. NRF2 translocation was determined by immunohistochemistry, with morphological changes monitored by hematoxylin and eosin staining. Following light exposure, βE2 significantly reduced ROS production. βE2 also up-regulated NRF2 mRNA and protein levels, with maximal expression at 4 and 12h post-exposure, respectively. Interestingly, following βE2 administration, NRF2 was translocated from the cytoplasm to the nucleus, primarily in the outer nuclear layer. βE2 also up-regulated NRF2, which triggered phase-2 antioxidant enzyme expression (superoxide dismutases 1 and 2, catalase, glutaredoxins 1 and 2, and thioredoxins 1 and 2), reduced ROS production, and ameliorated retinal damage. However, the beneficial effects of βE2 were markedly suppressed by pretreatment with LY294002 or ICI182780, specific inhibitors of the phosphatidylinositol 3-kinase-Akt (PI3K/AKT), and estrogen receptor (ER) signaling pathways, respectively. Taken together, these observations suggest that βE2 exerts antioxidative effects following light-induced retinal degeneration potentially via NRF2 activation. This protective mechanism may depend on two pathways: a rapid, non-genomic-type PI3K/AKT response, and a genomic-type ER-dependent response. Our data provide evidence that βE2 is a potentially effective in the treatment of retinal degeneration diseases.

Adenovirus-mediated artificial MicroRNAs targeting matrix or nucleoprotein genes protect mice against lethal influenza virus challenge

Influenza virus (IV) infection is a major public health problem, causing millions of cases of severe illness and as many as 500 000 deaths each year worldwide. Given the limitations of current prevention or treatment of acute influenza, novel therapies are needed. RNA interference (RNAi) through microRNAs (miRNA) is an emerging technology that can suppress virus replication in vitro and in vivo. Here, we describe a novel strategy for the treatment of infuenza based on RNAi delivered by a replication-defective adenovirus (Ad) vector, derived from chimpanzee serotype 68 (AdC68). Our results showed that artificial miRNAs (amiRNAs) specifically targeting conserved regions of the IV genome could effectively inhibit virus replication in human embryonic kidney 293 cells. Moreover, our results demonstrated that prophylactic treatment with AdC68 expressing amiRNAs directed against M1, M2 or nucleoprotein genes of IV completely protected mice from homologous A/PR8 virus challenge and partially protected the mice from heterologous influenza A virus strains such as H9N2 and H5N1. Collectively, our data demonstrate that amiRNAs targeting the conserved regions of influenza A virus delivered by Ad vectors should be pursued as a novel strategy for prophylaxis of IV infection in humans and animals.

DNA-templated silver nanoclusters for multiplexed fluorescent DNA detection

Novel label-free/conjugation-free molecular beacons are designed based on DNA templated-silver nanoclusters for multiplexed DNA detection. The assay is implemented in solution, which makes it easy for the in-situ and real-time analysis. This study demonstrates a new method for multiplexd detection of biological molecules by using fluorescent Ag nanocluster-based molecular beacon probes.

Single-layer transition metal dichalcogenide nanosheet-based nanosensors for rapid, sensitive, and multiplexed detection of DNA

Single-layer transition metal dichalcogenide nanosheets, including MoS2, TiS2, and TaS2, are used as novel sensing platforms for sensitive and selective detection of DNA, based on their high fluorescence-quenching ability and different affinities toward single-stranded DNA and double-stranded DNA. Importantly, for the first time, a single-layer TaS2 nanosheet-based multiplexed DNA sensor is also developed.

In vitro subminimum inhibitory concentrations of macrolide antibiotics induce macrolide resistance in Mycoplasma pneumoniae

AIM

This study aims to investigate the inducing effect of subminimum inhibitory concentrations of macrolide antibiotics on Mycoplasma pneumoniae (M. pneumoniae) resistance to drugs.

MATERIALS AND METHODS

One M. pneumoniae reference strain M129 (ATCC 29342) and 104 clinical isolates were incubated at 37C for 6-8 days. Genomic DNA of M. pneumoniae was extracted using TIANamp Bacteria DNA kit and amplified by polymerase chain reaction (PCR).

RESULTS

Ten sensitive isolates obtained from 104 M. pneumoniae clinical isolates were induced by subminimum inhibitory concentrations of macrolide antibiotics. Among them, three were found to possess mutations in L4 and L22 ribosomal proteins. Two cases carried simultaneously the C162A and A430G mutations of L4 and the T279C mutation of L22. In addition, one case had only the A209T mutation of L4.

CONCLUSIONS

Repeated in vitro exposure to subminimum inhibitory concentrations of macrolide antibiotics could induce selective mutations in ribosomal genes of M. pneumoniae clinical isolates that cause resistance to macrolide antibiotics. Hippokratia 2015, 19 (1): 57-62.

Downregulation of spinal endomorphin-2 correlates with mechanical allodynia in a rat model of tibia cancer

The endogenous tetrapeptide endomorphin-2 (EM2) participates in pain modulation by binding to pre- and/or post-synaptic μ opioid receptor (MOR). In the present study, pathological expression and antinociceptive effects of EM2 at the spinal level were investigated in a rat model of bone cancer pain. The model was established by introducing Walker 256 mammary gland carcinoma cells into the tibia medullary cavity. Immunohistochemical staining for EM2 showed a markedly reduced EM2-immunoreactivity in the ipsilateral spinal dorsal horn on days 6, 12 and 18 post Walker 256 inoculation (p < 0.05). Intrathecal injection (i.t.) of EM2 significantly attenuated cancer-induced mechanical allodynia (p < 0.05) which could be blocked by β-funaltrexamine (β-FNA), the μ receptor antagonist (p < 0.05). Furthermore, topical application of EM2 dose-dependently inhibited the electrically evoked C-fiber responses and postdischarge of wide dynamic range (WDR) neurons within the spinal cord (p < 0.05), and pretreatment with β-FNA abolished the hyperactivity of these neurons. Compared with the antinociception of morphine which took effect from 40 min to 100 min post application, the analgesic action of EM2 was characterized by quick onset and short-lived efficacy (p < 0.05), being most potent at 10 min and lasting about 20 min. These findings indicate that the down-regulated spinal EM2 is an important contributor to the neuropathological process of bone cancer pain and enhancing activation of EM2/μ receptor signaling might provide a therapeutic alternative to optimizing the treatment of cancer-induced bone pain.

Detection of Salmonella spp. by a loop-mediated isothermal amplification (LAMP) method targeting bcfD gene

In this study, we developed and validated a loop-mediated isothermal amplification (LAMP) assay for Salmonella detection targeting bcfD gene, a conserved fimbrial operon gene existing in Salmonella. The Salmonella LAMP assay we developed successfully amplified 44 Salmonella strains (14 standard strains and 30 clinical isolates), but none of 9 non-Salmonella standard strains (Proteus mirabilis, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Shigella flexneri, Shigella sonnei, Klebsiella pneumoniae, Campylobacter jejuni and Vibrio parahemolyticus). The detection limit was 5 CFU of Salmonella pure culture or 200 CFU of artificially spiked faeces per reaction system (equivalent to 5000 CFU g(-1) of faeces), and this method could directly detect Salmonella in chicken faeces free of pre-enrichment in a reaction time of 25 min. Our experiments show that the LAMP method we developed is a rapid, sensitive, specific and practical method for Salmonella detection. The Salmonella LAMP assay can potentially serve as new on-site diagnostics in the food and agricultural industries.

SIGNIFICANCE AND IMPACT OF THE STUDY

A loop-mediated isothermal amplification (LAMP) assay was established to detect Salmonella targeting bcfD gene, a conserved fimbrial operon gene. The detection limit was 5 CFU of Salmonella pure culture or 200 CFU of artificially spiked faeces per reaction system (equivalent to 5000 CFU g(-1) of faeces), and this method could directly detect Salmonella in chicken faeces free of pre-enrichment in a reaction time of 25 min. The Salmonella LAMP assay is a rapid, sensitive, specific and practical method for Salmonella detection and can potentially serve as new on-site diagnostics in the food and agricultural industries.

Increased toll-like receptor 9 expression is associated with the severity of paraquat-induced lung injury in mice

BACKGROUND

Toll-like receptor 9 (TLR9), an important component of the innate immune system, contributes to the pathogenesis of lung injury. However, its role in paraquat (PQ)-induced lung injury has not been studied.

METHOD

Mice were divided into PQ group (n = 24) and control group (n = 12). Mice in both groups were killed on either day 7 or day 28 after PQ (40 mg/kg intraperitoneally) or saline administration. TLR9 expression was evaluated through real-time polymerase chain reaction and immunohistochemistry. Concurrently, histopathological examinations of lung tissues were performed. On day 7, the lung weight to body weight ratios (LW/BW), total protein content, and inflammatory cytokine levels in bronchoalveolar lavage fluid (BALF) were measured. On day 28, fibrogenic cytokine expressions in lung tissues were measured. The correlations between TLR9 messenger RNA (mRNA) expression and different indicators of lung injury were then evaluated.

RESULTS

TLR9 expression was significantly increased over time in lung tissues after PQ poisoning. On day 7, TLR9 expression increased in parallel with LW/BW ratio (r = 0.403, p < 0.05), BALF protein content (r = 0.706, p<0.01), and BALF inflammatory cytokine levels (interleukin 6 (IL-6): r = 0.619, IL-1β: r = 0.930, tumor necrosis factor α: r = 0.589, all p < 0.05). On day 28, elevated TLR9 expression was closely correlated with Ashcroft score (r = 0.726, p < 0.01), mRNA expressions of α-smooth muscle actin, type I collagen and type III collagen (r = 0.926, 0.957, and 0.924, respectively; all p < 0.01).

CONCLUSIONS

The TLR9 expression in lung tissue is markedly elevated during PQ-induced acute lung injury and pulmonary fibrosis and positively correlated with the severity of lung injury in mice.

Assessment of dentinal tubule invasion capacity of Enterococcus faecalis under stress conditions ex vivo

AIM

To investigate the dentinal tubule invasion capacity of Enterococcus faecalis under alkaline and energy starvation stress conditions.

METHODOLOGY

The root canals from human single-rooted teeth (n = 40) were infected with E. faecalis under alkaline (pH 9, 10, 11 and 12) and energy starvation (no glucose, 0.05% glucose and 0.15% glucose) stress conditions. The root canals were prepared in a standard manner and treated to remove the smear layer before incubation. After 4 weeks of cultivation, the roots were split vertically into two halves: one half was processed for biofilm formation analysis using a scanning electron microscope; the other half was stained with fluorescent DNA-binding reagents, washed thoroughly and sectioned (100 μm thick), and the depth of tubule invasion by the microorganism was examined by confocal laser-scanning microscopy. The extent of dentine tubule invasion was analysed statistically.

RESULTS

The E. faecalis strain resulted in biofilm formation and dentine tubules invasion under all of the stress conditions, except for pH 11 and 12 conditions. However, the tubule penetration distance was markedly reduced in these stress conditions (P < 0.01) compared with in tryptic soy broth (TSB) or pH 7 medium. The invasion depth in the middle root dentine was significantly higher than in the apical sections in TSB and energy starvation medium (P < 0.01).

CONCLUSIONS

Ex vivo E. faecalis formed biofilms and colonized dentine under alkaline and glucose starvation stress conditions, but its ability to invade dentine tubules was significantly decreased.

The cAMP-responsive element binding protein (CREB) transcription factor regulates furin expression during human trophoblast syncytialization

INTRODUCTION

The multinucleated syncytiotrophoblast is formed and maintained by cytotrophoblast cell fusion and serves multiple functions to ensure a successful pregnancy. We have previously reported that the proprotein convertase furin is required for trophoblast syncytialization by processing type 1 insulin-like growth factor receptor (IGF1R).

METHODS

Utilizing trophoblast cell fusion models including induced fusion of choriocarcinoma BeWo cells and spontaneous fusion of primary cultured term cytotrophoblast cells, the expression of furin was evaluated by quantitative real-time PCR, Western blotting and immunofluorescence. The key transcription factor regulating the FUR gene promoter and critical responsive elements were identified by luciferase reporter assays, truncated mutants analysis, site-directed mutagenesis and ChIP.

RESULTS

We demonstrated that the levels of FUR mRNA were significantly stimulated by cAMP/PKA signaling pathway during spontaneous fusion of cytotrophoblast cells and forskolin-induced fusion of BeWo cells. cAMP-responsive element binding protein (CREB) was proven to be the key transcription factor which regulated the FUR P1 promoter during forskolin-induced BeWo cell fusion, and two critical cAMP-responsive elements (CREs) in the P1 promoter were further identified. Finally, we showed that CREB mediated endogenous furin activation and that CREB siRNA attenuated forskolin-induced furin expression and cell fusion in BeWo cells.

DISCUSSION

This provides the first evidence of the upstream regulator of furin during trophoblast cell fusion.

CONCLUSIONS

The above results suggest that the FUR transcription is activated by CREB-dependent stimulation of the FUR P1 promoter during human trophoblast syncytialization.

Effects of dietary lysine levels on apparent nutrient digestibility and serum amino Acid absorption mode in growing pigs

Two experiments were conducted to determine the effects of different dietary lysine levels on the apparent nutrient digestibility, the serum amino acid (AA) concentration, and the biochemical parameters of the precaval and portal vein blood in growing pigs. In Experiment 1, 15 noncannulated pigs received diets with different lysine densities (0.65%, 0.95%, and 1.25% lysine) for 13 d. A total collection digestion test was performed, and blood samples were collected from the precaval vein at the end of the experiment. In Experiment 2, four cannulated pigs were fed the same diets of Experiment 1. The experiment used a self-control experimental design and was divided into three periods. On d 5 of each period, at 0.5 h before feeding and hourly up to 8 h after feeding, single blood samples were collected from catheters placed in the portal vein. In Experiment 1, some serum AAs (including lysine), serum urinary nitrogen (SUN), and total protein (TP) concentrations were significantly affected by the dietary lysine levels (p<0.05). Moreover, the 0.65% lysine treatment showed a significant lower apparent digestibility of gross energy, dry matter, crude protein, and phosphorus than the other treatments (p<0.05). In Experiment 2, serum lysine, histidine, phenylalanine, threonine, valine, isoleucine (p = 0.0588), triglyceride, and SUN (p = 0.0572) concentrations were significantly affected by the dietary lysine levels (p<0.05). Additionally, almost all of the determined serum AA and total AA concentrations reached their lowest values at 0.5 h before feeding and their highest values at 2 h after feeding (p<0.05). These findings indicate that the greatest absorption of AA occurred at 2 h after feeding and that the dynamic profile of serum AA is affected by the dietary lysine levels. Moreover, when the dietary lysine content was 0.95%, the growing pigs achieved a better nutrient digestibility and serum metabolites levels.

A second-generation genetic linkage map for bighead carp (Aristichthys nobilis) based on microsatellite markers

Bighead carp (Aristichthys nobilis) is an important aquaculture fish worldwide. Genetic linkage maps for the species were previously reported, but map resolution remained to be improved. In this study, a second-generation genetic linkage map was constructed for bighead carp through a pseudo-testcross strategy using interspecific hybrids between bighead carp and silver carp. Of the 754 microsatellites genotyped in two interspecific mapping families (with 77 progenies for each family), 659 markers were assigned to 24 linkage groups, which were equal to the chromosome numbers of the haploid genome. The consensus map spanned 1917.3 cM covering 92.8% of the estimated bighead carp genome with an average marker interval of 2.9 cM. The length of linkage groups ranged from 52.2 to 133.5 cM with an average of 79.9 cM. The number of markers per linkage group varied from 11 to 55 with an average of 27.5 per linkage group. Normality tests on interval distances of the map showed a non-normal marker distribution; however, significant correlation was found between the length of linkage group and the number of markers below the 0.01 significance level (two-tailed). The length of the female map was 1.12 times that of the male map, and the average recombination ratio of female to male was 1.10:1. Visual inspection showed that distorted markers gathered in some linkage groups and in certain regions of the male and female maps. This well-defined genetic linkage map will provide a basic framework for further genome mapping of quantitative traits, comparative mapping and marker-assisted breeding in bighead carp.

Polyoma small T antigen triggers cell death via mitotic catastrophe

Polyoma small T antigen (PyST), an early gene product of the polyoma virus, has been shown to cause cell death in a number of mammalian cells in a protein phosphatase 2A (PP2A)-dependent manner. In the current study, using a cell line featuring regulated expression of PyST, we found that PyST arrests cells in mitosis. Live-cell and immunofluorescence studies showed that the majority of the PyST expressing cells were arrested in prometaphase with almost no cells progressing beyond metaphase. These cells exhibited defects in chromosomal congression, sister chromatid cohesion and spindle positioning, thereby resulting in the activation of the spindle assembly checkpoint. Prolonged mitotic arrest then led to cell death via mitotic catastrophe. Cell cycle inhibitors that block cells in G1/S prevented PyST-induced death. PyST-induced cell death that occurs during M is not dependent on p53 status. These data suggested, and our results confirmed, that PP2A inhibition could be used to preferentially kill cancer cells with p53 mutations that proliferate normally in the presence of cell cycle inhibitors.

Refractive index sensor based on the leaky radiation of a microfiber

In this work we present a refractive index sensor based on the leaky radiation of a microfiber. The 5.3um diameter microfiber is fabricated by drawing a commercial optical fiber. When the microfiber is immersed into a liquid with larger refractive index than the effective index of fiber mode, the light will leak out through the leaky radiation process. The variation of refractive index of liquid can be monitored by measuring radiation angle of light. The refractive index sensitivity can be over 400 degree/RIU in theory. In the experiment, the variation value 0.001 of refractive index of liquid around this microfiber can be detected through this technique. This work provides a simple and sensitive method for refractive index sensing application.

A five-microRNA panel in plasma was identified as potential biomarker for early detection of gastric cancer

BACKGROUND

Circulating microRNAs (miRNAs) have been implicated as novel biomarkers for gastric cancer (GC) diagnosis. However, the mixture of GC subtypes may have led to the inconsistent circulating miRNA profiles, and the clinical performance of circulating miRNAs has not yet been evaluated independently on early detection of GC.

METHODS

A four-phase study was designed with a total of 160 cancer-free controls, 124 patients with gastric non-cardia adenocarcinoma (GNCA) and 36 patients diagnosed gastric cardia adenocarcinoma (GCA). In the discovery phase, we screened the miRNA expression profile in plasma of 40 GNCA patients (stage I) and 40 matched controls by TaqMan low density array (TLDA) chips with pooled samples. Differentially expressed miRNAs were further validated in individual sample using quantitative reverse-transcriptase PCR (qRT-PCR) in the training phase. Subsequently, in an independent validation phase, the identified miRNAs were evaluated in 48 GNCA patients (stage I) and 102 matched controls. Finally, the identified miRNAs were further assessed in an external validation phase including advanced GNCA and GCA patients. Additionally, the expression levels of identified miRNAs were measured in the media of BGC823 and MGC803 cell lines.

RESULTS

Five miRNAs (miR-16, miR-25, miR-92a, miR-451 and miR-486-5p) showed consistently elevated levels in plasma of the GC patients as compared with controls, and were identified to be potential markers for GNCA with area under the receiver operating characteristic (ROC) curves (AUCs) ranging from 0.850 to 0.925 and 0.694 to 0.790 in the training and validation phases, respectively. The five-miRNA panel presented a high diagnostic accuracy for the early-stage GNCA (AUCs=0.989 and 0.812 for the training and validation phases, respectively). Three miRNAs (miR-16, miR-25 and miR-92a) were excreted into the culture media of GC cell lines.

CONCLUSIONS

The five-miRNA panel in plasma may serve as a potential non-invasive biomarker in detecting the early-stage GC.

Lactobacillus salivarius Ren prevent the early colorectal carcinogenesis in 1, 2-dimethylhydrazine-induced rat model

AIMS

The objective of this study was to investigate the impact of Lactobacillus salivarius Ren (LS) on modulating colonic micro flora structure and influencing host colonic health in a rat model with colorectal precancerous lesions.

METHODS AND RESULTS

Male F344 rats were injected with 1, 2-dimethylhydrazine (DMH) and treated with LS of two doses (5 × 10(8) and 1 × 10(10) CFU kg(-1) body weight) for 15 weeks. The colonic microflora profiles, luminal metabolites, epithelial proliferation and precancerous lesions [aberrant crypt foci (ACF)] were determined. A distinct segregation of colonic microflora structures was observed in LS-treated group. The abundance of one Prevotella-related strain was increased, and the abundance of one Bacillus-related strain was decreased by LS treatment. These changes were accompanied by increased short-chain fatty acid levels and decreased azoreductase activity. LS treatment also reduced the number of ACF by c. 40% and suppressed epithelial proliferation.

CONCLUSIONS

Lactobacillus salivarius Ren improved the colonic microflora structures and the luminal metabolisms in addition preventing the early colorectal carcinogenesis in DMH-induced rat model.

SIGNIFICANCE AND IMPACT OF THE STUDY

Colonic microflora is an important factor in colorectal carcinogenesis. Modulating the structural shifts of microflora may provide a novel option for preventing colorectal carcinogenesis. This study suggested a potential probiotic-based approach to modulate the intestinal microflora in the prevention of colorectal carcinogenesis.

Observation of a charged charmoniumlike structure in e+ e- → (D* D*)± π∓ at √s = 4.26 GeV

We study the process e+ e- →(D* D*)± π∓ at a center-of-mass energy of 4.26 GeV using a 827  pb(-1) data sample obtained with the BESIII detector at the Beijing Electron Positron Collider. Based on a partial reconstruction technique, the Born cross section is measured to be (137±9±15)  pb. We observe a structure near the (D* D*)± threshold in the π∓ recoil mass spectrum, which we denote as the Zc±(4025). The measured mass and width of the structure are (4026.3±2.6±3.7)  MeV/c2 and (24.8±5.6±7.7)  MeV, respectively. Its production ratio σ(e+ e- → Zc±(4025)π∓ → (D* D*)± π∓)/σ(e+ e- → (D* D*)± π∓) is determined to be 0.65±0.09±0.06. The first uncertainties are statistical and the second are systematic.

Amplified detection of femtomolar DNA based on a one-to-few recognition reaction between DNA-Au conjugate and target DNA

A sensitive electrochemical DNA biosensor based on the amplification of Au nanoparticles (AuNPs) has been developed. The AuNPs were modified with two types of signaling reporter DNAs, i.e. a methylene blue probe (MB-probe 2-SH) and T10 with a methylene blue signaling molecule (MB-T10-SH), forming DNA-AuNP conjugates. The MB-probe 2-SH is complementary to the target DNA, while MB-T10-SH is not. The presence of MB-T10-SH reduces the cross-reaction between target DNA and MB-probe 2-SH on the AuNPs, resulting in increased sensitivity of the biosensor. In our assay, the DNA sensor is fabricated by immobilizing a capture probe on the surface of the Au electrode, which then hybridizes with the corresponding target DNA, and further hybridizes with a DNA-Au conjugate. The signal of MB is measured by differential pulse voltammetry, while the DNA-Au conjugate enables the detection of target DNA in the linear range of 10(-13) to 10(-8) M with the detection limit as low as 50 fM.

Development of a low-dose fast-dissolving tablet formulation of Newcastle disease vaccine for low-cost backyard poultry immunisation

The immunisation of backyard poultry is critical for maintaining healthy flocks to provide nutrition and income for low-resource farmers worldwide. A vaccine presentation for flocks of less than 50 birds could make it more affordable and accessible, increasing uptake and impact. Fast-dissolving tablets (FDT) of Newcastle disease virus (NDV) vaccine were produced by freeze drying the LaSota NDV strain combined with excipients into tablets containing a small number of doses and packaged in polymer blister sheets. The NDV-FDT vaccine maintained virus stability for more than six months at 4°C, based on plaque assay and egg infectivity dose data. Stability was further confirmed in a challenge study, where the tablet vaccine elicited a strong immune response and provided 100 per cent protection to vaccinated chickens infected with a virulent strain of NDV. The vaccine tablet can be diluted in water (no needle or syringe required) and administered either in drinking water or with a dropper via an intraocular and/or intransal route. Results indicate that FDTs containing a small number of doses are a feasible presentation for backyard poultry farmers. The compact packaging of the FDTs will also provide cost savings in storing and distributing the vaccine in the cold chain.

VEGF and BMP-2 promote bone regeneration by facilitating bone marrow stem cell homing and differentiation

Vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) have been widely used in the fields of tissue engineering and regenerative medicine to stimulate angiogenesis and bone formation. The goal of this study was to determine whether VEGF and BMP-2 are involved in the homing of bone marrow stem cells (BMSCs) for bone regeneration and to provide insights into their mechanism of action. The chemoattraction of BMSCs to VEGF and BMP-2 was analysed in vitro using a checkerboard assay. VEGF and BMP-2 stimulated the chemotaxis of BMSCs but not chemokinesis. In vivo, both VEGF and BMP-2 also have been confirmed to induce the homing of tail vein injected BMSCs to the site of silk scaffold subcutaneous implantation in nude mice. When the scaffolds were implanted in the rabbit skull defects, more SSEA+ mesenchymal stem cells were mobilised and homed to silk scaffolds containing VEGF and/or BMP-2. More importantly, autogenic BMSCs were reinjected via the ear vein after labelling with lenti-GFP, and the cells were detected to home to the defects and differentiate into endothelial cells and osteogenic cells induced by VEGF and BMP-2. Finally, perfusion with Microfil showed that initial angiogenesis was enhanced in tissue-engineered complexes containing VEGF. Observations based on µCT assay and histological study revealed that bone formation was accelerated on BMP-2-containing scaffolds. These findings support our hypothesis that the localised release of VEGF and BMP-2 promote bone regeneration, in part by facilitating the mobilisation of endogenous stem cells and directing the differentiation of these cells into endothelial and osteogenic lineages.

MyoD and Myf6 gene expression patterns in skeletal muscle during embryonic and posthatch development in the domestic duck (Anas platyrhynchos domestica)

The MyoD and Myf6 genes, which are muscle regulatory factors (MRFs), play major roles in muscle growth and development and initiate muscle fibre formation via the regulation of muscle-specific gene translation. Therefore, MyoD and Myf6 are potential candidate genes for meat production traits in animals and poultry. The objective of this study was to evaluate MyoD and Myf6 gene expression patterns in the skeletal muscle during early developmental stage of ducks. Gene expression levels were detected using the quantitative RT-PCR method in the breast muscle (BM) and leg muscle (LM) at embryonic days 13, 17, 21, 25, 27, as well as at 1 week posthatching in Gaoyou and Jinding ducks (Anas platyrhynchos domestica). The MyoD and Myf6 gene profiles in the two duck breeds were consistent during early development, and MyoD gene expression showed a 'wave' trend in BM and an approximate 'anti-√' trend in LM. Myf6 gene expression in BM showed the highest level at embryonic day 21, which subsequently decreased, although remained relatively high, while levels at embryonic days 13, 17 and 21 were higher in LM. The results of correlation analysis showed that MyoD and Myf6 gene expression levels were more strongly correlated in LM than in BM in both duck breeds. These results indicated that different expression patterns of the MyoD and Myf6 genes in BM and LM may be related to muscle development and differentiation, suggesting that MyoD and Myf6 are integral to skeletal muscle development.

Solvothermal-induced conversion of one-dimensional multilayer nanotubes to two-dimensional hydrophilic VOx nanosheets: synthesis and water treatment application

Ultrathin 2D nanostructures have shown many unique properties and are attractive for various potential applications. Here, we demonstrated a strategy to synthesize ultrathin VOx nanosheets. The as-obtained ultrathin VOx nanosheets showed a large Brunauer-Emmett-Teller (BET) surface area of 136.3 m2 g(-1), which is much larger than that of 1D multilayer VOx nanotubes. As a proof of concept, these hydrophilic ultrathin nanosheets were applied in water treatment and exhibited excellent absorption capability to remove Rhodamine B (RhB) in wastewater owing to their large specific surface area, good hydrophilic property, and more negative zeta potential. In addition, this method could be generalized to prepare other 2D nanostructures with great potential for various attractive applications.