Bone loss in the oestrogen-depleted rat is not exacerbated by sitagliptin, either alone or in combination with a thiazolidinedione

Antihyperglycaemic therapy on bone was evaluated in the ovariectomized (OVX), non-diabetic adult rat. Animals were treated daily for 12 weeks with various doses of sitagliptin, pioglitazone, rosiglitazone, combinations of sitagliptin with pioglitazone or vehicle alone. Sitagliptin target engagement was confirmed by assessing inhibition of plasma dipeptidyl peptidase-4 (DPP-4) and oral glucose tolerance. Parameters related to bone health were evaluated in femur and vertebrae by dual-energy X-ray absorptiometry and histomorphometry. Bone mineral density (BMD) generally did not differ significantly between OVX-sitagliptin-treated animals and OVX-vehicle controls. In lumbar vertebrae, however, there was significantly less BMD loss with increasing sitagliptin dose. Thiazolidinedione (TZD) treatment generally resulted in lower BMD; OVX-TZD-treated (but not OVX-sitagliptin-treated) animals also had lessened cortical thickness in central femur and profoundly greater bone marrow adiposity in lumbar vertebrae. These findings support prior findings with TZDs and suggest a neutral or beneficial impact of DPP-4 inhibition on bone health.

Immune focusing and enhanced neutralization induced by HIV-1 gp140 chemical cross-linking

Experimental vaccine antigens based upon the HIV-1 envelope glycoproteins (Env) have failed to induce neutralizing antibodies (NAbs) against the majority of circulating viral strains as a result of antibody evasion mechanisms, including amino acid variability and conformational instability. A potential vaccine design strategy is to stabilize Env, thereby focusing antibody responses on constitutively exposed, conserved surfaces, such as the CD4 binding site (CD4bs). Here, we show that a largely trimeric form of soluble Env can be stably cross-linked with glutaraldehyde (GLA) without global modification of antigenicity. Cross-linking largely conserved binding of all potent broadly neutralizing antibodies (bNAbs) tested, including CD4bs-specific VRC01 and HJ16, but reduced binding of several non- or weakly neutralizing antibodies and soluble CD4 (sCD4). Adjuvanted administration of cross-linked or unmodified gp140 to rabbits generated indistinguishable total gp140-specific serum IgG binding titers. However, sera from animals receiving cross-linked gp140 showed significantly increased CD4bs-specific antibody binding compared to animals receiving unmodified gp140. Moreover, peptide mapping of sera from animals receiving cross-linked gp140 revealed increased binding to gp120 C1 and V1V2 regions. Finally, neutralization titers were significantly elevated in sera from animals receiving cross-linked gp140 rather than unmodified gp140. We conclude that cross-linking favors antigen stability, imparts antigenic modifications that selectively refocus antibody specificity and improves induction of NAbs, and might be a useful strategy for future vaccine design.

The Role of the Atrial Neural Network In Atrial Fibrillation: The Metastatic Progression Hypothesis

With the advent of catheter ablation of atrial fibrillation (AF) there has been acceleration in our understanding of the mechanisms underlying the etiology of this common clinical arrhythmia. In this regard, the role of the intrinsic cardiac autonomic nervous system in the initiation and maintenance of AF began to receive attention in numerous experimental and clinical investigations. Up to now, the focus has been on the large ganglionated plexi (GP) which are located in the posterior left atrium mainly at the pulmonary vein-atrial junctions. As long term outcomes have been reported and single procedures have indicated diminished success rates particularly for persistent/long standing persistent AF, emphasis has begun to shift away from the pulmonary vein isolation (PVI) alone as well as GP ablation with or without PVI. An understanding of the atrial substrate represented by the extensions of the intrinsic cardiac autonomic system constituting the atrial neural network is beginning to evolve. In this review, the contribution of the intrinsic cardiac autonomic nervous system to the etiology of AF is addressed, particularly in regard to the greater prevalence of AF in the elderly. In addition, we emphasize the involvement of the atrial neural network in the "metastatic" progression of paroxysmal to persistent and long standing persistent forms of AF.

FliS modulates FlgM activity by acting as a non-canonical chaperone to control late flagellar gene expression, motility and biofilm formation in Yersinia pseudotuberculosis

The FlgM-FliA regulatory circuit plays a central role in coordinating bacterial flagellar assembly. In this study, we identified multiple novel binding partners of FlgM using bacterial two-hybrid screening. Among these binding partners, FliS, the secretion chaperone of the filament protein FliC, was identified to compete with FliA for the binding of FlgM. We further showed that by binding to FlgM, FliS protects it from secretion and degradation, thus maintaining an intracellular pool of FlgM reserved as the FliS-FlgM complex. Consequently, we found that the flagellar late-class promoter activities are significantly increased in the fliS deletion mutant. The fliS mutant is weakly motile and shows significantly increased biofilm formation on biotic surface. Based on the results obtained, we established for the first time the regulatory role of the flagellin chaperone FliS to fine-tune late flagellar assembly by modulating FlgM activity.

Chemoprevention gene therapy (CGT): novel combinatorial approach for preventing and treating pancreatic cancer

Pancreatic cancer remains one of the deadliest of all cancers despite aggressive surgical treatment combined with adjuvant radiotherapy and chemotherapy. Chemoresistance and radioresistance are the principal causes of failure of pancreatic cancer patients to respond to therapy. Conditionally replication competent adenovirus (CRCA)-based cancer gene therapy is an innovative strategy for treating cancers displaying inherent resistance to treatment. Limitations of current adenovirus (Ad)-based gene therapies for malignant tumors include lack of cancer-specificity, and effective and targeted delivery. To remedy this situation, CRCAs have been designed that express E1A, necessary for Ad replication, under the control of a cancer-specific progression elevated gene-3 promoter (PEG-Prom) with concomitant expression of an immunomodulatory cytokine, such as mda-7/IL-24 or interferon-γ (IFN-γ), under the control of a ubiquitous and strong cytomegalovirus promoter (CMV-Prom) from the E3 region. These bipartite CRCAs, when armed with a transgene, are called cancer terminator viruses (CTVs), i.e., Ad.PEG-E1A-CMV-mda-7 (CTV-M7) and Ad.PEG-E1A-CMV-IFN-γ (CTV-γ), because of their universal effectiveness in cancer treatment irrespective of p53/pRb/p16 or other genetic alterations in tumor cells. In addition to their selective oncolytic effects in tumor cells, the potent 'bystander antitumor' properties of MDA-7/IL-24 and IFN-γ embody the CTVs with expanded treatment properties for both primary and distant cancers. Pancreatic cancer cells display a "translational block" of mda-7/IL-24 mRNA, limiting production of MDA-7/IL-24 protein and cancer-specific apoptosis. Specific chemopreventive agents abrogate this "translational block" resulting in pancreatic cancer-specific killing. This novel chemoprevention gene therapy (CGT) strategy holds promise for both prevention and treatment of pancreatic cancers where all other strategies have proven ineffective.

Pontibacter toksunensis sp. nov., isolated from soil, and emended descriptions of Pontibacter roseus and Pontibacter akesuensis

A Gram-reaction-negative, rod-shaped, non-motile, red-pigmented bacterial strain, designated ZLD-7(T), was isolated from a soil sample collected from an arid area in Xinjiang Province in north-west China, and characterized by using a polyphasic taxonomic approach. 16S rRNA gene sequence analysis showed that strain ZLD-7(T) was a member of the genus Pontibacter in the family Cytophagaceae, with sequence similarities of 93.7-96.2 % to type strains of other Pontibacter species. The only isoprenoid quinone of strain ZLD-7(T) was MK-7, and its major cellular fatty acids were summed feature 4 (anteiso-C17 : 1 B and/or iso-C17 : 1 I), iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The polar lipid profile consisted of phosphatidylethanolamine, one unidentified aminolipid and four unidentified polar lipids. The DNA G+C content was 47.8 mol%. On the basis of the evidence presented, it is proposed that strain ZLD-7(T) represents a novel species of the genus Pontibacter, for which the name Pontibacter toksunensis sp. nov. is proposed. The type strain is ZLD-7(T) ( = CCTCC AB 208003(T) = KCTC 23984(T)). Emended descriptions of Pontibacter roseus and Pontibacter akesuensis are also proposed.

LXRα-mediated downregulation of FOXM1 suppresses the proliferation of hepatocellular carcinoma cells

Liver X receptors (LXRs), including LXRα and LXRβ isoforms, have important roles in the metabolic regulation of glucose, cholesterol and lipid. Moreover, activation of LXRs also represses the expression of cyclin D1 and cyclin B1, and thus suppresses the proliferation of multiple cancer cells, but the relevant mechanism is not well known. Forkhead box M1 (FOXM1) is a proliferation-specific member of forkhead box family, which is highly expressed in proliferating normal cells and numerous cancer cells. FOXM1 directly activates transcription of cyclin D1 and cyclin B1, resulting in the enhancement of cell cycle progression and cell proliferation. However, it is unclear whether LXRs are involved in the regulation of FOXM1. In this study, we demonstrated that specific LXRs agonists downregulated expression of FOXM1, cyclin D1 and cyclin B1 in hepatocellular carcinoma (HCC) cells, which led to cell cycle and cell proliferation arrest. Knockdown of FOXM1 significantly alleviated LXRs activation-mediated cell cycle arrest and cell growth suppression. Reporter assays showed that the activation of LXRs significantly reduced the transcriptional activity of FOXM1 promoter. Electrophoretic mobility shift assay and chromatin immunoprecipitation assays demonstrated that LXRα but not LXRβ could bind to an inverted repeat IR2 (-52CCGTCAcgTGACCT-39) in the promoter region of FOXM1 gene. Moreover, the xenograft tumor growth and the corresponding FOXM1 expression in nude mice were dramatically repressed by LXRs agonists. Taken together, we conclude that LXRα but not LXRβ functions as a transcriptional repressor for FOXM1 expression. The pathway 'LXRα-FOXM1-cyclin D1/cyclin B1' is a novel mechanism by which LXRs suppress the proliferation of HCC cells, suggesting that the pathway may be a novel target for HCC treatment.

Expression of interleukin-22 in myasthenia gravis

IL-17 and IL-22 are implicated in the pathogenesis of autoimmune diseases. The roles of IL-22 in the pathophysiology of myasthenia gravis (MG) remain unsettled. The aim of this study was to investigate the possible relationship between serum IL-22, IL-17 levels, anti-acetylcholine receptor antibody (anti-AChR Ab) titres and clinical parameters in patients with MG. The serum IL-22, IL-17 levels and anti-AChR Ab titres were tested by enzyme-linked immunosorbent assay (ELISA), while the expression of IL-22 and IL-17 mRNAs in peripheral blood mononuclear cells (PBMC) from healthy and MG subjects were detected by quantitative real-time PCR (qRT-PCR). Furthermore, PBMC from 12 patients with generalized MG were purified and treated with recombinant human IL-22 (rhIL-22), the IL-17 levels of supernatant were detected by ELISA. We found that the IL-17 levels were significantly increased, but IL-22 levels were significantly decreased in the serum of patients with MG compared with healthy controls. Consistantly, a significant decrease in IL-22 mRNA levels and an increase in IL-17 mRNA levels were detected in PBMC collected from patients with MG, compared with healthy controls. A negative correlation between IL-22 mRNA in PBMC, serum IL-22 and serum anti-AChR Ab levels was found in patients with MG. Moreover, in cultured MG PBMC treated with recombinant human IL-22 (rhIL-22), the IL-17 levels were decreased in a dose-dependent manner. Our findings indicated a possible role of IL-22 as a protective factor in MG.

Groupwise whole-brain parcellation from resting-state fMRI data for network node identification

In this paper, we present a groupwise graph-theory-based parcellation approach to define nodes for network analysis. The application of network-theory-based analysis to extend the utility of functional MRI has recently received increased attention. Such analyses require first and foremost a reasonable definition of a set of nodes as input to the network analysis. To date many applications have used existing atlases based on cytoarchitecture, task-based fMRI activations, or anatomic delineations. A potential pitfall in using such atlases is that the mean timecourse of a node may not represent any of the constituent timecourses if different functional areas are included within a single node. The proposed approach involves a groupwise optimization that ensures functional homogeneity within each subunit and that these definitions are consistent at the group level. Parcellation reproducibility of each subunit is computed across multiple groups of healthy volunteers and is demonstrated to be high. Issues related to the selection of appropriate number of nodes in the brain are considered. Within typical parameters of fMRI resolution, parcellation results are shown for a total of 100, 200, and 300 subunits. Such parcellations may ultimately serve as a functional atlas for fMRI and as such three atlases at the 100-, 200- and 300-parcellation levels derived from 79 healthy normal volunteers are made freely available online along with tools to interface this atlas with SPM, BioImage Suite and other analysis packages.

An antiapoptotic Bcl-2 family protein index predicts the response of leukaemic cells to the pan-Bcl-2 inhibitor S1

BACKGROUND

Bcl-2-like members have been found to be inherently overexpressed in many types of haematologic malignancies. The small-molecule S1 is a BH3 mimetic and a triple inhibitor of Bcl-2, Mcl-1 and Bcl-XL.

METHODS

The lethal dose 50 (LD(50)) values of S1 in five leukaemic cell lines and 41 newly diagnosed leukaemia samples were tested. The levels of Bcl-2 family members and phosphorylated Bcl-2 were semiquantitatively measured by western blotting. The interactions between Bcl-2 family members were tested by co-immunoprecipitation. The correlation between the LD(50) and expression levels of Bcl-2 family members, alone or in combination, was analysed.

RESULTS

S1 exhibited variable sensitivity with LD(50) values ranging >2 logs in both established and primary leukaemic cells. The ratio of pBcl-2/(Bcl-2+Mcl-1) could predict the S1 response. Furthermore, we demonstrated that pBcl-2 antagonised S1 by sequestering the Bak and Bim proteins that were released from Mcl-1, andpBcl-2/Bak, pBcl-2/Bax and pBcl-2/Bim complexes cannot be disrupted by S1.

CONCLUSION

A predictive index was obtained for the novel BH3 mimetic S1. The shift of proapoptotic proteins from being complexed with Mcl-1 to being complexed with pBcl-2 was revealed for the first time, which is the mechanism underlying the index value described herein.

Radiological and clinical features of adult non-puerperal mastitis

OBJECTIVE

To describe the radiological and clinical features of adult non-puerperal mastitis and to determine the most accurate method of preventing unnecessary surgical procedures.

METHODS

Clinical and imaging findings were retrospectively reviewed in 51 females with non-puerperal mastitis, which was confirmed by biopsy/surgical pathology. All 51 patients had pre-operative MRI; 45 patients also had sonograms and 25 also had mammograms, pre-operatively.

RESULTS

Of the 51 cases with non-puerperal mastitis, 94.1% (48/51) were confirmed as having acute or chronic inflammation, and the other 3 had plasma cell mastitis; areola papillaris inflammation was found in 39.2% (20/51) of the cases. Overall, 6 of the 25 cases that were examined with mammography and 2 of the 45 cases that were examined with sonography appeared normal, but all 51 lesions were positively identified on MRI. Asymmetrical density (12/25) on mammograms and solitary or separated/contiguous, clustered, hypoechoic mass-like lesions (31/45) on ultrasound were the most common signs of non-puerperal mastitis. On enhanced MRI, 90.2% (46/51) of patients showed non-mass-like enhanced lesions. Multiple regional enhancements in the pattern of distribution (32/46) and separated or contiguous, clustered, rim-like enhancements in the pattern of internal enhancement (29/46) were the most common manifestations in non-mass-like enhanced lesions. Of the 51 patients, mastitis Type 1 and Type 2 in the time-signal intensity curve were detected in 47.1% and 51.0% of the patients, respectively. The breast imaging reporting and data system categories with the highest number of patients were Category 0 (9/25) on mammography, Category 4a on sonography (18/45) and Category 4a on MRI (29/51).

CONCLUSION

The findings from mammography and ultrasound are non-specific; therefore, using MR can be helpful in the diagnosis, especially in the presence of non-mass-like enhancements that are multiple, regional, separated, or contiguous, clustered and rim-like.

ADVANCES IN KNOWLEDGE

Mastitis is often neglected because of the lack of typical clinical signs and symptoms. This study has assessed and described the clinical features and imaging findings of adult non-puerperal mastitis on mammograms, sonograms and MRI and found that MRI is more specific in the diagnosis of disease.

Development of a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) system for rapid detection of HDV genotype 1

The object of this study was to develop a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for detecting hepatitis D virus (HDV) genotype 1. With an alignment analysis, a highly conserved sequence (nt 820-1020) was chosen as a suitable target to design LAMP primers. The optimal condition of RT-LAMP was a 25-μl reaction volume, which consists of the following components: 1·6 μmol l⁻¹ each of FIP and BIP, 0·2 μmol l⁻¹ each of F3 and B3, 1·5 μmol l⁻¹ dNTPs, 4 mmol l⁻¹ MgSO₄, 8 U Bst DNA polymerase, 2U M-MLV and 2 μl extracted RNA sample. The amplification reaction was carried out at 65°C for 50 min. Compared with conventional qualitative or quantitative real-time reverse transcription polymerase chain reaction, the results of RT-LAMP indicated a 1000-fold increase in sensitivity for detecting HDV. There was no cross-reaction for the RT-LAMP method between HDV 1 and HIV, HAV, HBV, HCV and HEV.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results indicate that RT-LAMP is a simple, rapid, specific, highly sensitive and cost-effective, field-based method for detecting HDV 1. The RT-LAMP assay is an acceptable alternative to diagnose the HDV genotype 1 and to investigate its epidemiology for clinical laboratories lacking specialized equipments.

A type VI secretion system regulated by OmpR in Yersinia pseudotuberculosis functions to maintain intracellular pH homeostasis

Type VI secretion systems (T6SSs) which widely distributed in Gram-negative bacteria have been primarily studied in the context of cell interactions with eukaryotic hosts or other bacteria. We have recently identified a thermoregulated T6SS4 in the enteric pathogen Yersinia pseudotuberculosis. Here we report that OmpR directly binds to the promoter of T6SS4 operon and regulates its expression. Further, we observed that the OmpR-regulated T6SS4 is essential for bacterial survival under acidic conditions and that its expression is induced by low pH. Moreover, we showed that T6SS4 plays a role in pumping H(+) out of the cell to maintain intracellular pH homeostasis. The acid tolerance phenotype of T6SS4 is dependent on the ATPase activity of ClpV4, one of the components of T6SS4. These results not only uncover a novel strategy utilized by Y. pseudotuberculosis for acid resistance, but also reveal that T6SS, a bacteria secretion system known to be functional in protein transportation has an unexpected function in H(+) extrusion under acid conditions.

Nafulsella turpanensis gen. nov., sp. nov., a member of the phylum Bacteroidetes isolated from soil

A Gram-staining-negative, rod-shaped, gliding and pale-pink-pigmented bacterium, designated strain ZLM-10(T), was isolated from a soil sample collected from an arid area in Xinjiang province, China, and characterized in a taxonomic study using a polyphasic approach. The novel strain grew optimally at 30-37 °C and in the presence of 2 % (w/v) sea salts. The only respiratory quinone detected was MK-7 and the major cellular fatty acids were summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), iso-C15 : 0 and iso-C17 : 0 3-OH. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid and two unidentified aminophospholipids. The DNA G+C content was 45.4 mol%. Flexirubin-type pigments were not produced. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZLM-10(T) was a member of the phylum Bacteroidetes and appeared most closely related to Cesiribacter roseus 311(T) (90.2 % sequence similarity), Marivirga sericea LMG 13021(T) (89.2 %), Cesiribacter andamanensis AMV16(T) (89.1 %) and Marivirga tractuosa DSM 4126(T) (89.1 %). On the basis of phenotypic and genotypic data and phylogenetic inference, strain ZLM-10(T) should be classified as a novel species of a new genus in the family Flammeovirgaceae, for which the name Nafulsella turpanensis gen. nov., sp. nov. is proposed. The type strain of the type species is ZLM-10(T) ( = CCTCC AB 208222(T) = KCTC 23983(T)).

Tumor suppressor menin mediates peripheral nerve injury-induced neuropathic pain through potentiating synaptic plasticity

Synaptic plasticity is a crucial step in the development of central sensitization in the pathogenesis of neuropathic hyperalgesia. Menin, the product of the multiple endocrine neoplasia type 1 (MEN1) gene, possesses the property of synaptogenesis which plays an essential role in neuronal activity. We tested the contributing role of spinal menin in peripheral nerve injury-induced neuropathic hypersensitivity through modulating neuronal synaptic plasticity. After approval by the Institutional Animal Care and Use Committee, nociceptive responses were detected with von Frey filaments and thermal plate after spared nerve injury in C57BL/6 mice who were treated with either intrathecal antisense oligonucleotide of MEN1 (ASO) or vehicle. Extracellular spontaneous discharge frequency, field excitatory postsynaptic potential (fEPSP), and monosynaptic excitatory postsynaptic currents (EPSCs) were measured electrophysiologically. Intrathecal ASO alleviated nerve injury-induced mechanical and thermal hypersensitivity. Upregulated spinal menin after nerve injury colocalized with NeuN in the superficial laminae; genetic knockdown of spinal menin reduced nerve injury induced in vivo spontaneous activity and instantaneous frequency and in vitro field potentials; ASO decreased the frequency and amplitude of monosynaptic EPSCs, and reduced synaptic strength and total charge. Collectively, these findings highlight the role of upregulated neuronal menin in the spinal cord in potentiating spinal synaptic plasticity in peripheral nerve injury-induced neuropathic hypersensitivity.