A small-molecule-controlled system for efficient pseudotyping of prototype foamy virus vectors.

Foamy virus (FV) vector systems have recently demonstrated their power as efficient gene transfer tools for different target tissues. Unfortunately, FVs cannot be naturally pseudotyped by heterologous viral glycoproteins due to an unusual particle morphogenesis involving a FV Env-dependent particle release process. Therefore, current FV vector systems are constrained to the broad host cell range provided by the cognate viral glycoprotein. We evaluated different approaches for pseudotyping of FV vectors, in which the specific FV Gag-Env interaction, essential for particle egress, is substituted by a small-molecule controlled heterodimerization (HD) system. In one system developed, one HD-domain (HDD) is fused to a membrane-targeting domain (MTD), such as the human immunodeficiency virus (HIV) Gag matrix (MA) subunit, with a second fused to the FV capsid protein. Coexpression of both components with different heterologous viral glycoproteins allowed an efficient, dimerizer-dependent pseudotyping of FV capsids. With this system FV vesicular stomatitis virus glycoprotein (VSV-G) pseudotype titers greater than 1 × 10(6) IU/ml were obtained, at levels comparable to authentic FV vector particles. As a proof-of-principle we demonstrate that Pac2 cells, naturally resistant to FV vectors, become permissive to FV VSV-G pseudotypes. Similar to other retroviral vectors, this FV pseudotyping system now enables adaptation of cell-specific targeting approaches for FVs.

Transcription activation of myostatin by trichostatin A in differentiated C2C12 myocytes via ASK1-MKK3/4/6-JNK and p38 mitogen-activated protein kinase pathways.

Myostatin is a negative regulator of skeletal muscle mass. The pathways employed in modulating myostatin gene expression are scarcely known. We aimed to determine the signaling pathway of myostatin induction by a histone deacetylase (HDAC) inhibitor-trichostatin A (TSA) in differentiated C(2)C(12) myocytes. TSA increased myostatin mRNA expression up to 40-fold after treatment for 24 h, and induced myostatin promoter activity up to 3.8-fold. Pretreatment with actinomycin D reduced the TSA-induced myostatin mRNA by 93%, suggesting TSA-induced myostatin expression mainly at the transcriptional level. Pretreatment with p38 MAPK (SB203580) and JNK (SP600125) inhibitors, but not ERK (PD98059) inhibitor, blocked TSA-induced myostatin expression, respectively, by 72% and 43%. Knockdown of p38 MAPK by RNAi inhibited the TSA-induced myostatin expression by 77% in C(2)C(12) myoblasts. The protein levels of phosphorylated p38 MAPK, JNK, but not ERK, increased with TSA treatment in differentiated C(2)C(12) cells. Direct activation of p38 MAPK and JNK by anisomycin in the absence of TSA increased myostatin mRNA by fourfold. The phosphorylated form of the kinase MKK3/4/6 and ASK1, upstream cascades of p38 MAPK and JNK, also increased with TSA treatment. We concluded that the induction of myostatin by TSA treatment in differentiated C(2)C(12) cells is in part through ASK1-MKK3/6-p38 MAPK and ASK1-MKK4-JNK signaling pathways. Activation of p38 MAPK and JNK axis is necessary, but not sufficient for TSA-induced myostatin expression.

[The adaptation process and behavioral responses of a patient with peripheral arterial occlusive disease who has undergone amputation].

The purpose of this study was to explore the adaptation and behavioral responses of an 85 year-old woman who suffered from gangrene related to peripheral arterial occlusive disease and finally underwent lower limb amputation. The field method was adopted. Records of the patient's behaviors were collected by observation and interviews. The data were recorded by nursing process recording and analyzed using the Behavior Classification Model. The findings showed the patient's behavioral responses to be categorized by three phases. The first phase was the impact phase: patient objected to amputation strongly because it would destroy her body image. She experienced moods of anxiety and denial moods etc. The second phase was the regressive phase: after the amputation, the patient experienced a sense of loss and discomfort while having to cooperate with medical treatment and rehabilitation. Silence, withdrawal, and despair were some of her reactions. The third phase was the acceptance/ reconstruction phase: the patient accepted the fact of her amputation with time and started her rehabilitation. During the process of providing nursing care, we helped the patient to vent her emotional responses, helped her to develop awareness of her ability to face the loss of her limb, and aggressively planned individualized rehabilitation for her. Finally, these interventions enabled the patient to overcome the impact of her amputation. The findings of this study should provide references for further clinical nursing care.

Severity of spontaneous echo contrast in the jugular vein associated with ischemic stroke.

This study evaluated the relationship between spontaneous echo contrast (SEC) in the internal jugular vein (JV), atherosclerotic markers and ischemic stroke. One hundred twenty patients with acute ischemic stroke and 120 controls were recruited. SEC score correlated with plasma level of fibrinogen (coefficient: 0.105, p = 0.022), hemoglobin (coefficient: 0.122, p = 0.008) and presence of JV reflux (coefficient: 0.314, p < 0.001) and peak flow velocity (coefficient: -0.244, p < 0.001) in the corresponding JV, but did not correlate with carotid plaque score (coefficient: 0.042, p = 0.358) or intima-media thickness (coefficient: 0.067, p = 0.303). Multivariate regression analysis revealed that fibrinogen level, SEC score, intima-media thickness, plaque score and history of coronary artery disease were associated with acute ischemic stroke. In conclusion, the severity of SEC in the JV might represent the tendency toward thrombogenesis in diseased cerebral circulation possibly through mechanisms other than arterial atherosclerosis.

Relationship between acute stroke outcome, aspirin resistance, and humoral factors.

BACKGROUND: The relationship between biochemical aspirin resistance (AR) and functional outcome of acute ischemic stroke is uncertain. METHODS: Prospectively, 269 patients with acute ischemic stroke were recruited. Their responsiveness to aspirin was evaluated by platelet function analyzer (PFA-100). All patients received blood tests for fibrinogen, high-sensitivity C-reactive protein (hs-CRP), CD40-ligand, P-selectin, intercellular adhesion molecule -1, von Willebrand factor (vWF), and D-dimer. The patients' National Institutes of Health Stroke Scale and modified Rankin Scale scores were recorded on admission, at 30 days, and at 90 days after stroke. RESULTS: Closure-time measured by PFA-100 equipped with epinephrine/collagen cartridge (Epi-CT) was <193 seconds (defined as AR) in 83 patients (30.9%). Patients with AR were less likely to have favorable outcome at 30 days (47.0%, p = 0.047; odds ratio: 0.69, 0.48-0.99) and 90 days (57.8%, p = 0.037; odds ratio: 0.69, 0.47-0.97) after stroke compared with those of patients without AR (60.2% and 71.0%, respectively). The Epi-CT correlated with closure-time measured by adenosine diphosphate/collagen cartridge (r = 0.241, p < 0.001), blood white cell count (r = -0.125, p = 0.041), low density lipoprotein cholesterol (r = 0.120, p = 0.050), hs-CRP (r = -0.150, p = 0.015), vWF (r = -0.134, p = 0.028), and body mass index (r = 0.143, p = 0.019). Multivariate logistic regression analysis showed that higher National Institutes of Health Stroke Scale at admission, atrial fibrillation, increased plasma levels of hs-CRP, and D-dimer were independent predictors for unfavorable stroke outcome at 90 days. CONCLUSION: Aspirin resistance evaluated by PFA-100 test was associated with unfavorable 90-day outcome. However, AR determined by PFA-100 dose not predict 90-day functional outcome. The results of PFA-100 testing represented a complex interaction between drug effect, inflammatory reaction, and prothrombotic activity.