微创入路在脊柱手术中的应用

微创入路脊柱手术（MASS）是在经典微创脊柱手术（MISS）基础上发展而来的新的微创脊柱外科技术。MASS通过应用一些特殊设备或器械,经微创手术入路在直视下完成脊柱手术,减少手术入路对周围组织的损伤,同时又能达到传统开放手术同样的手术效果。MASS有效结合了MISS与开放手术的优势,减少了传统开放手术和MISS手术的并发症,具有手术组织创伤小、学习曲线相对MISS缩短、疗效确切、术后恢复快、医疗效价比高等优点,临床应用日益广泛。     

Abciximab readministration: A single-operator community-hospital experience

Abciximab, a monoclonal antibody to the platelet glycoprotein IIb/IIIa receptor, reduces ischemic complications of coronary interventions after first administration. In this study, We sought to determine whether readministration of abciximab is associated with equal efficacy and safety. We retrospectively reviewed the charts of 35 patients who received two doses of abciximab at separate intervals. We monitored patients clinically for recurrent ischemia, bleeding complications, and thrombocytopenia. We measured hemoglobin and platelet counts before and after readministration of abciximab. There was no cardiac-related death, myocardial infarction, or recurrent ischemia. No obvious bleeding occurred in any of the 35 patients, although 1 patient had a drop of hemoglobin >3 gm/dl. We observed one episode of severe thrombocytopenia without any complication, and this patient improved without requiring platelet transfusion. There was no profound thrombocytopenia. We conclude that readministration of abciximab was well tolerated without any evidence of altered efficacy or safety. Cathet. Cardiovasc. Intervent. 47:294–296, 1999. © 1999 Wiley-Liss, Inc.     

Exposure to far‐infrared ray attenuates methamphetamine‐induced impairment in recognition memory through inhibition of protein kinase C δ in male mice: Comparison with the antipsychotic clozapine

We have previously demonstrated that repeated treatment with methamphetamine (MA) results in a recognition memory impairment via upregulation of protein kinase C (PKC) δ and downregulation of the glutathione peroxidase‐1 (GPx‐1)‐dependent antioxidant system. We also demonstrated that far‐infrared ray (FIR) attenuates acute restraint stress via induction of the GPx‐1 gene. Herein, we investigated whether exposure to FIR modulates MA‐induced recognition memory impairment in male mice, and whether cognitive potentials mediated by FIR require modulation of the PKCδ gene, extracellular signal‐regulated kinase (ERK) 1/2, and glutathione‐dependent system. Repeated treatment with MA significantly increased PKCδ expression and its phosphorylation out of PKC isoenzymes (i.e., PKCα, PKCβI, PKCβII, PKCζ, and PKCδ expression) in the prefrontal cortex of mice. Exposure to FIR significantly attenuated MA‐induced increase in phospho‐PKCδ and decrease in phospho‐ERK 1/2. In addition, FIR further facilitated the nuclear factor E2‐related factor 2 (Nrf2)‐dependent glutathione synthetic system. Moreover, L‐buthionine‐(S, R)‐sulfoximine, an inhibitor of glutathione synthesis, counteracted the FIR‐mediated phospho‐ERK 1/2 induction and memory‐enhancing activity against MA insult. More important, positive effects of FIR are comparable to those of genetic depletion of PKCδ or the antipsychotic clozapine. Our results indicate that FIR protects against MA‐induced memory impairment via activations of the Nrf2‐dependent glutathione synthetic system, and ERK 1/2 signaling by inhibition of the PKCδ gene.     

Benzofuran sulfonates and small self-lipid antigens activate type II NKT cells via CD1d

Natural killer T (NKT) cells detect lipids presented by CD1d. Most studies focus on type I NKT cells that express semi-invariant αβ T cell receptors (TCR) and recognize α-galactosylceramides. However, CD1d also presents structurally distinct lipids to NKT cells expressing diverse TCRs (type II NKT cells), but our knowledge of the antigens for type II NKT cells is limited. An early study identified a nonlipidic NKT cell agonist, phenyl pentamethyldihydrobenzofuransulfonate (PPBF), which is notable for its similarity to common sulfa drugs, but its mechanism of NKT cell activation remained unknown. Here, we demonstrate that a range of pentamethylbenzofuransulfonates (PBFs), including PPBF, activate polyclonal type II NKT cells from human donors. Whereas these sulfa drug–like molecules might have acted pharmacologically on cells, here we demonstrate direct contact between TCRs and PBF-treated CD1d complexes. Further, PBF-treated CD1d tetramers identified type II NKT cell populations expressing αβTCRs and γδTCRs, including those with variable and joining region gene usage (TRAV12-1–TRAJ6) that was conserved across donors. By trapping a CD1d–type II NKT TCR complex for direct mass-spectrometric analysis, we detected molecules that allow the binding of CD1d to TCRs, finding that both selected PBF family members and short-chain sphingomyelin lipids are present in these complexes. Furthermore, the combination of PPBF and short-chain sphingomyelin enhances CD1d tetramer staining of PPBF-reactive T cell lines over either molecule alone. This study demonstrates that nonlipidic small molecules, which resemble sulfa drugs implicated in systemic hypersensitivity and drug allergy reactions, are targeted by a polyclonal population of type II NKT cells in a CD1d-restricted manner.

Natural killer T (NKT) cells are defined as T cells that are restricted to the lipid antigen-presenting molecule, CD1d. The most extensively studied are type I NKT cells, which typically express an invariant T cell receptor (TCR)-α chain consisting of TRAV10–TRAJ18 in humans (TRAV11–TRAJ18 in mice) paired with a constrained repertoire of TCR-β chains, enriched for TRBV25 in humans (TRBV13, 29, 1 in mice) (reviewed in ref. 1). Type I NKT cells are defined by their strong responses to α-galactosylceramide (α-GalCer) and structurally related hexosylceramides presented by CD1d, while in contrast, type II NKT cells are defined as CD1d-restricted T cells that express diverse TCRs and do not recognize α-GalCer (reviewed in refs. 1 and 2). Very little is known about the chemical identity of antigens for type II NKT cells; however, some studies suggest that these cells are abundant in humans (3–5), and, by virtue of their greater TCR diversity, they can interact with a broader range of antigens compared to type I NKT cells (2, 6–14).In 2004, a nonlipidic molecule, phenyl pentamethyldihydrobenzofuransulfonate (PPBF), was described that stimulated a human TRAV10⁻ (type II) NKT cell line (clone ABd) in a CD1d-dependent manner (15). These observations were notable because PPBF resembles various sulfonamide drugs: furosemide (diuretic), sulfasalazine (disease-modifying antirheumatic), and celecoxib (anti-inflammatory) as well as “sulfa” antibiotics such as sulfonamide, sulfapyridine, sulfamethoxazole, sulfadiazine, and sulfadoxine (16). These drugs can cause systemic delayed-type hypersensitivity reactions, which are thought to be mediated by T cells (17–20). Most of our limited understanding of drug hypersensitivity reactions comes from work focusing on Human Leukocyte Antigen (HLA)-restricted conventional T cells, which has led to the proposal of four main mechanisms for small-drug immune activity as reviewed in ref. 21: 1) hapten/prohapten formation, whereby the drug reacts with self-Ags to generate a neo-product that undergoes processing and presentation to T cells; 2) noncovalent/labile pharmacological interaction with immune receptors on the cell surface; 3) superantigen mediating direct linkage of TCRs and Ag-presenting molecules; and 4) anchor site occupation by small molecules in Ag-presenting molecules inducing an altered self-Ag repertoire (22). Whether the CD1d-NKT cell axis is implicated in drug hypersensitivity remains unclear (23). Whereas most antigens in the CD1d system are lipids that use their alkyl chains to bind to CD1d, PPBF is a polycyclic small molecule and so would have to act through an atypical display mechanism. As previous attempts to stain the ABd clone with CD1d-PPBF tetramers were unsuccessful, the atypical drug-like structure of PPBF raised the possibility of direct pharmacological action on T cells rather than the presentation of CD1d-PPBF complexes to TCRs. However, the mechanism of PPBF-mediated type II NKT cell activation remains undefined (15).Here, using TCR-transduced cell lines, CD1d tetramers treated with PPBF, and new analogs in the pentamethylbenzofuransulfonate (PBF) family, we discovered that several molecules stimulate polyclonal NKT cells. Using CD1d tetramers treated with a newly identified and more potent analog of PPBF, we identified populations of type II NKT cells that comprise a polyclonal repertoire of both αβ and γδ T cells, including those with conserved TCR sequences. This enigmatic nature of T cell responses to PBF molecules was resolved using TCR trap technology (24, 25). Mass-spectrometric analysis of all molecules present in CD1d-PBF-TCR complexes indicates that CD1d binds PBFs and small self-lipids that promote CD1d-TCR binding. These data support a model of type II NKT cell recognition of small sulfa drug–like compounds in association with CD1d and flag a possible mechanism in which such cells may be involved in sulfa drug hypersensitivity.     

Unconventional treatment options in severe asthma: an overivew

In Canada, asthma is the leading cause of admission in hospital. About of 80% of the death from asthma is preventable. Severe asthma is defined as a patient with persistent symptoms despite the use of adequate controller therapy, including multiple courses of oral glucocorticosteroids. However, about 10% of patients with severe asthma remain poorly controlled despite optimal treatment and these patients have the greatest morbidity and mortality. The management of refractory severe asthma remains extremely challenging. For patients with refractory severe asthma, the adjunct therapies recommended by national guidelines only included oral glucocorticosteroid and anti-IgE antibody (omalizumab) therapy. Currently, there is limited published literature on the unconventional treatments of refractory severe asthma. The objective of this review article is to provide an updated therapeutic overview of unconventional treatment options for refractory severe asthma.     

Pseudomonas aeruginosa bacteremia in children over ten consecutive years: analysis of clinical characteristics, risk factors of multi-drug resistance and clinical outcomes

This study aimed to evaluate the clinical profiles, antibiotic susceptibility, risk factors of multi-drug resistance (MDR) and outcomes of P. aeruginosa bacteremia in children by retrospective methods at a tertiary teaching children's hospital in Seoul, Korea during 2000-2009. A total of 62 episodes were evaluated and 59 patients (95.2%) had underlying diseases. Multivariate analysis demonstrated that an intensive care unit (ICU) stay within the previous one month was the only independent risk factor for MDR P. aeruginosa bacteremia (odds ratio [OR], 6.8; 95% confidence interval [CI], 1.3-35.8, P = 0.023). The overall fatality rate associated with P. aeruginosa bacteremia was 14.5% (9 of 62). The fatality rate in patients with MDR P. aeruginosa was 57.1%, compared with 9.1% in non-MDR patients (OR 13.3; 95% CI 2.3-77.2, P = 0.006). However, the presence of respiratory difficulty was the only independent risk factor for overall fatality associated with P. aeruginosa bacteremia according to multivariate analysis (OR 51.0; 95% CI 7.0-369.0, P < 0.001). A previous ICU stay and presentation with respiratory difficulty were associated with acquisition of MDR P. aeruginosa and a higher fatality rate, respectively. Future efforts should focus on the prevention and treatment of P. aeruginosa bacteremia in high-risk children.