Spontaneous inflammatory pain model from a mouse line with N-ethyl-N-nitrosourea mutagenesis

Background

Most filarial nematodes contain Wolbachia symbionts. The purpose of this study was to examine the effects of doxycycline on gene expression in Wolbachia and adult female Brugia malayi.

Methods

Brugia malayi infected gerbils were treated with doxycycline for 6-weeks. This treatment largely cleared Wolbachia and arrested worm reproduction. RNA recovered from treated and control female worms was labeled by random priming and hybridized to the Version 2- filarial microarray to obtain expression profiles.

Results and discussion

Results showed significant changes in expression for 200 Wolbachia (29% of Wolbachia genes with expression signals in untreated worms) and 546 B. malayi array elements after treatment. These elements correspond to known genes and also to novel genes with unknown biological functions. Most differentially expressed Wolbachia genes were down-regulated after treatment (98.5%). In contrast, doxycycline had a mixed effect on B. malayi gene expression with many more genes being significantly up-regulated after treatment (85% of differentially expressed genes). Genes and processes involved in reproduction (gender-regulated genes, collagen, amino acid metabolism, ribosomal processes, and cytoskeleton) were down-regulated after doxycycline while up-regulated genes and pathways suggest adaptations for survival in response to stress (energy metabolism, electron transport, anti-oxidants, nutrient transport, bacterial signaling pathways, and immune evasion).

Conclusions

Doxycycline reduced Wolbachia and significantly decreased bacterial gene expression. Wolbachia ribosomes are believed to be the primary biological target for doxycycline in filarial worms. B. malayi genes essential for reproduction, growth and development were also down-regulated; these changes are consistent with doxycycline effects on embryo development and reproduction. On the other hand, many B. malayi genes involved in energy production, electron-transport, metabolism, anti-oxidants, and others with unknown functions had increased expression signals after doxycycline treatment. These results suggest that female worms are able to compensate in part for the loss of Wolbachia so that they can survive, albeit without reproductive capacity. This study of doxycycline induced changes in gene expression has provided new clues regarding the symbiotic relationship between Wolbachia and B. malayi.     

The Roles of Albumin Levels in Head and Neck Cancer Patients with Liver Cirrhosis Undergoing Tumor Ablation and Microsurgical Free Tissue Transfer

Objective

To evaluate the changes of serum albumin levels during the peri-operative period, and correlate these changes to surgical outcomes, postoperative morbidity and mortality in head and neck cancer patients with cirrhosis.

Methods

57 patients with liver cirrhosis out of 3,022 patients who underwent immediate free flap reconstruction after surgical ablation of head and neck cancer performed over a 9-year period were included in the study. Two sets of groups were arranged based on the preoperative albumin (>3.5 g/dL vs. ≤ 3.5 g/dL) and POD1 albumin (>2.7 g/dL vs. ≤ 2.7 g/dL) levels and were compared with respect to patient-related variables, surgical outcomes, medical and surgical complications, and mortalities.

Results

All patients had significant decreases in albumin levels postoperatively. Hypoalbuminemia, both preoperative and postoperative, was associated with the model for end-stage liver disease (MELD) score, the amount of blood loss, the duration of ICU stay and hospital stay, and postoperative medical and surgical complications. In particular, preoperative hypoalbuminemia (serum albumin ≤ 3.5 g/dL) was associated strongly with medical complications and mortality, while postoperative hypoalbuminemia (serum albumin ≤ 2.7 g/dL) with surgical complications.

Conclusion

Our study demonstrated the prognostic values of albumin levels in head and neck cancer patient with liver cirrhosis. The perioperative albumin levels can be utilized for risk stratification to potentially improve surgical and postoperative management of these challenging patients.     

Evidence providing new insights into TOB-promoted deadenylation and supporting a link between TOB's deadenylation-enhancing and antiproliferative activities

The mammalian TOB1 and TOB2 proteins have emerged as key players in repressing cell proliferation. Accumulating evidence indicates that TOBs regulate mRNA deadenylation. A recruitment model was proposed in which TOBs promote deadenylation by recruiting CAF1-CCR4 deadenylase complex to the 3' end of mRNAs by simultaneously binding CAF1 and PABP. However, the exact molecular mechanism underlying TOB-promoted deadenylation remains unclear. It is also unclear whether TOBs' antiproliferative and deadenylation-promoting activities are connected. Here, we combine biochemical analyses with a functional assay directly monitoring deadenylation and mRNA decay to characterize the effects of tethering TOBs or their mutant derivatives to mRNAs. The results provide direct evidence supporting the recruitment model and reveal a link between TOBs' antiproliferative and deadenylation-promoting activities. We also find that TOBs' actions in deadenylation are independent of the phosphorylation state of three serines known to regulate antiproliferative actions, suggesting that TOBs arrest cell growth through at least two different mechanisms. TOB1 and TOB2 were interchangeable in the properties tested here, indicating considerable functional redundancy between the two proteins. We propose that their multiple modes of modulating mRNA turnover and arresting cell growth permit the TOB proteins to coordinate their diverse roles in controlling cell growth and differentiation.     

Curcumin alleviates eosinophilic meningitis through reduction of eosinophil count following albendazole treatment against Angiostrongylus cantonensis in mice

Angiostrongylus cantonensis (A. cantonensis) is the most common cause of parasitic eosinophilic meningitis worldwide. By using an animal model of BALB/c mice infected with A. cantonensis, previous studies indicated that the anthelmintic drug, albendazole, could kill A. cantonensis larvae and prevent further infection. However, the dead larvae will induce severe immune responses targeting at brain tissues. To alleviate the detrimental effects caused by the dead larvae, we administered curcumin, a traditional anti-inflammatory agent, as a complementary treatment in addition to albendazole therapy, to determine whether curcumin could be beneficial for treatment. The results showed that although curcumin treatment alone did not reduce worm number, combined treatment by albendazole and curcumin helped to reduce eosinophil count in the cerebrospinal fluid, better than using albendazole alone. This alleviating effect did not affect albendazole treatment alone, since histological analysis showed similar worm eradication with or without addition of curcumin. Nevertheless, curcumin treatment alone and combined albendazole-curcumin treatment did not inhibit MMP-9 expression in the brain tissue. In conclusion, curcumin, when used as a complementary treatment to albendazole, could help to alleviate eosinophilic meningitis through suppression of eosinophil count in the cerebrospinal fluid.     

RIG1 suppresses Ras activation and induces cellular apoptosis at the Golgi apparatus

Retinoid-inducible gene 1 encodes RIG1 is a growth regulator, which inhibits the pathways of the RAS/mitogen-activated protein kinases by suppressing the activation of RAS. Confocal microscopic analysis demonstrated that RIG1 is localized in the endoplasmic reticulum (ER) and Golgi apparatus in HtTA cervical cancer cells. Carboxyterminal-deleted RIG1 targeted to the Golgi or ER was constructed and validated. The activation of HRAS was inhibited by 25.1% or 81.4% in cells cotransfected with wild-type or Golgi-targeted RIG1, respectively. Expression of wild-type or Golgi-targeted RIG1 for 24 h induced cellular apoptosis in HtTA cells, as assessed by MTT assay, the release of lactate dehydrogenase, and chromatin condensation. In contrast, ER-targeted RIG1 and carboxyterminal-deleted RIG1 (RIG1DeltaC) exhibited no activity. Caspase-2, -3, and -9 were activated following the expression of wild-type and Golgi-targeted RIG1. Although the caspase-3 inhibitor Z-DEVD-FMK partially or completely reversed the cell death induced by wild-type or Golgi-targeted RIG1, it did not prevent the anti-RAS effect of RIG1. In conclusion, the proapoptotic and anti-RAS activities of RIG1 are primarily associated with the Golgi localization of the protein. The proapoptotic activities of RIG1 are mediated through the activation of caspase-2 and -3 and are independent of its effect on RAS.     

Use of CHADS2 and CHA2DS2-VASc Scores to Predict Subsequent Myocardial Infarction,Stroke, and Death in Patients with Acute Coronary Syndrome: Data from Taiwan Acute Coronary Syndrome Full Spectrum Registry

Background

Acute coronary syndrome (ACS) patients have a wide spectrum of risks for subsequent cardiovascular events and death. However, there is no simple, convenience scoring system to identify risk of adverse outcomes. We investigated whether CHADS₂ and CHA₂DS₂-VASc scores were useful tools to assess the risk for adverse events among ACS patients.

Methods

This observational prospective study was conducted at 39 hospitals. Totally 3,183 patients with ACS were enrolled, and CHADS₂ and CHA₂DS₂-VASc scores were calculated. The primary endpoint was occurrence of adverse event, including subsequent myocardial infarction, stroke, or death, within 1 year of discharge.

Results

CHADS₂ and CHA₂DS₂-VASc scores were significant predictors of adverse events in separate multivariate regression analyses. A Kaplan-Meier analysis of CHADS₂ and CHA₂DS₂-VASc scores of ≥2 showed a higher rate of adverse events as compared with scores of <2 (P<0.001;log-rank test). CHA₂DS₂-VASc score was better than CHADS₂ score in predicting subsequent adverse events; the area under the receiver operating characteristic curve increased from 0.66 to 0.70 (p<0.001). Patients with CHADS₂ scores of 0 or 1 were further classified according to CHA₂DS₂-VASc score, using a cutoff value of 2. The rate of adverse events significantly differed between those with a score of <2 and those with a score of ≥2 (4.1% vs.10.7%, P<0.001).

Conclusions

CHADS₂ and CHA₂DS₂-VASc scores were useful predictors of subsequent adverse events in ACS patients.     

n-Butylidenephthalide Protects against Dopaminergic Neuron Degeneration and α-Synuclein Accumulation in Caenorhabditis elegans Models of Parkinson's Disease

Background

Parkinson''s disease (PD) is the second most common degenerative disorder of the central nervous system that impairs motor skills and cognitive function. To date, the disease has no effective therapies. The identification of new drugs that provide benefit in arresting the decline seen in PD patients is the focus of much recent study. However, the lengthy time frame for the progression of neurodegeneration in PD increases both the time and cost of examining potential therapeutic compounds in mammalian models. An alternative is to first evaluate the efficacy of compounds in Caenorhabditis elegans models, which reduces examination time from months to days. n-Butylidenephthalide is the naturally-occurring component derived from the chloroform extract of Angelica sinensis. It has been shown to have anti-tumor and anti-inflammatory properties, but no reports have yet described the effects of n-butylidenephthalide on PD. The aim of this study was to assess the potential for n-butylidenephthalide to improve PD in C. elegans models.

Methodology/Principal Findings

In the current study, we employed a pharmacological strain that expresses green fluorescent protein specifically in dopaminergic neurons (BZ555) and a transgenic strain that expresses human α-synuclein in muscle cells (OW13) to investigate the antiparkinsonian activities of n-butylidenephthalide. Our results demonstrate that in PD animal models, n-butylidenephthalide significantly attenuates dopaminergic neuron degeneration induced by 6-hydroxydopamine; reduces α-synuclein accumulation; recovers lipid content, food-sensing behavior, and dopamine levels; and prolongs life-span of 6-hydroxydopamine treatment, thus revealing its potential as a possible antiparkinsonian drug. n-Butylidenephthalide may exert its effects by blocking egl-1 expression to inhibit apoptosis pathways and by raising rpn-6 expression to enhance the activity of proteasomes.

Conclusions/Significance

n-Butylidenephthalide may be one of the effective neuroprotective agents for PD.     

Control of topology and dimensionality by aromatic dicarboxylate pendant arm position and length in cadmium coordination polymers incorporating a hydrogen-bonding capable kinked dipyridine ligand

Hydrothermal synthesis has afforded three cadmium coordination polymers incorporating both an aromatic dicarboxylate ligand and the kinked and hydrogen-bonding capable organodiimine 4,4′-dipyridylamine (dpa). The positions and length of the pendant arms of the aromatric dicarboxylate moiety exerts a strong structure directing effect in this system. {[Cd(hmph)(dpa)] · H₂O}_n (1, hmph = homophthalate) possesses interdigitated herringbone (6,3) grid layers with an ABAB stacking pattern. {[Cd(1,3-phda)(dpa)(H₂O)] · 0.5H₂O}_n (2, 1,3-phda = 1,3-phenylenediacetate) exhibits a (4,4)-grid layer structure with two different aperture sizes and an unusual ABCD layer stacking pattern. Shortening the pendant arm length resulted in an uncommon CdSO₄-type (6⁵8 topology) 4-connected 3-D network in {[Cd(iph)(dpa)] · 4H₂O}_n (3, iph = isophthalate), whose uncoordinated water molecules occupy a sizable incipient void space of 23.7% of the unit cell volume. All three coordination polymers underwent blue-violet luminescence under ultraviolet irradiation.     

The application of stem cells in the treatment of ischemic diseases

Ischemia causes oxygen deprivation, cell injury and related organ dysfunction. Although ischemic injury may be local, it involves many biochemical changes in different cell types. The ability of stem cells to differentiate into different cell lineages provides the possibility of their use in treating a variety of diseases requiring tissue repair or reconstitution, such as stroke, ischemic retinopathy, myocardial infarction, ischemic disorders of the liver, ischemic renal failure, and ischemic limb dysfunction. Several cell types including embryonic stem cells, various progenitor and stem cells of hematopoietic or mesenchymal origin have been used in attempts to reconstitute injured tissue. Xenologous or autologous stem cells may be administered either through the peripheral vascular system or directly by regional injection. The stem cells are then guided to the infarct site by homing signals. Either by cell differentiation or paracrine effects, stem cells or progenitor cells participate in the reconstruction of a favorable microenvironment resulting in neovascularization and tissue regeneration that eventually improve the physiological function of organs with ischemic damage.     

The prostacyclin receptor induces human vascular smooth muscle cell differentiation via the protein kinase A pathway

Recent studies of cyclooxygenase-2 (COX-2) inhibitors suggest that the balance between thromboxane and prostacyclin is a critical factor in cardiovascular homeostasis. Disruption of prostacyclin signaling by genetic deletion of the receptor or by pharmacological inhibition of COX-2 is associated with increased atherosclerosis and restenosis after injury in animal models and adverse cardiovascular events in clinical trials (Vioxx). Human vascular smooth muscle cells (VSMC) in culture exhibit a dedifferentiated, migratory, proliferative phenotype, similar to what occurs after arterial injury. We report that the prostacyclin analog iloprost induces differentiation of VSMC from this synthetic, proliferative phenotype to a quiescent, contractile phenotype. Iloprost induced expression of smooth muscle (SM)-specific differentiation markers, including SM-myosin heavy chain, calponin, h-caldesmon, and SM alpha-actin, as determined by Western blotting and RT-PCR analysis. Iloprost activated cAMP/protein kinase A (PKA) signaling in human VSMC, and the cell-permeable cAMP analog 8-bromo-cAMP mimicked the iloprost-induced differentiation. Both myristoylated PKA inhibitor amide-(14-22) (PKI, specific PKA inhibitor), as well as ablation of the catalytic subunits of PKA by small interfering RNA, opposed the upregulation of contractile markers induced by iloprost. These data suggest that iloprost modulates VSMC phenotype via G(s) activation of the cAMP/PKA pathway. These studies reveal regulation of VSMC differentiation as a potential mechanism for the cardiovascular protective effects of prostacyclin. This provides important mechanistic insights into the induction of cardiovascular events with the use of selective COX-2 inhibitors.