In Vivo Anergized T Cells Form Altered Immunological Synapses In Vitro

T cells contact allogeneic antigen presenting cells (APCs) and assemble, at their contact interface, a molecular platform called the immunological synapse. Synapse-based molecules provide directional signals for the T cell--either positive signals, resulting in T-cell activation, or negative signals causing T-cell inactivation or anergy. To better understand the molecular basis of in vivo T-cell anergy we analyzed the contacts made between in vivo anergized T cells and APCs, and determined which signaling molecules were included or excluded from their immunological synapses. Anergy was induced in TCR transgenic mice by the intravenous injection of semiallogeneic donor spleen cells. T cells from anergized mice were mixed with APCs, the T-cell/APC synapses imaged using deconvolution microscopy, and their molecular compositions were determined. T cells from anergic mice formed unstable immunological synapses in vitro with allogeneic APCs and failed to recruit the signaling proteins necessary to initiate T-cell activation. These findings suggest that T-cell anergy induced by exposure to semiallogeneic donor cells is associated with defects in the earliest events of T-cell activation, immunological synapse formation and recruitment of TCR-mediated signaling proteins.     

Fat-Derived Hormone Adiponectin Combined with FTY720 Significantly Improves Small-for-Size Fatty Liver Graft Survival

Owing to the discrepancy between organ donation and the demand for liver transplantation, expanding the liver donor pool is of vital importance. However, marginal liver grafts, such as small-for-size and/or fatty grafts, were associated with primary graft nonfunction or poor function. Therefore, novel combination therapies to rescue small-for-size fatty liver grafts should be investigated. In this study, we applied a combination therapy using a fat-derived hormone adiponectin (anti-steatosis) plus immunomodulator FTY720 (anti-inflammatory) in a rat liver transplantation model using small-for-size fatty liver grafts, and investigated the underlying protective mechanism such as anti-steatosis, intra-graft energy metabolism, hepatic microcirculatory changes, cell signaling cascades for survival, apoptosis and inflammation. The current study demonstrated that even a single treatment of adiponectin or FTY720 improved the 7-day graft survival from 0% to 62.5% (p = 0.001). The combination therapy significantly increased the 7-day graft survival rate to 100% by remarkable attenuation of graft steatosis and acute phase inflammatory response, significant activation of cell survival Akt pathway and maintenance of intra-graft adenosine triphosphate metabolism and improvement of hepatic microcirculation. In conclusion, the fat-derived hormone adiponectin combined with FTY720 might be a novel combination drug therapy for prevention of small-for-size fatty liver graft injury.     

Voltage-Gated calcium channels and nonvoltage-gated calcium uptake pathways in the rat incisor odontoblast plasma membrane

Odontoblasts participate actively in the transport and accumulation of Ca²⁺ ions to the mineralization front during dentinogenesis. These cells are known to carry membrane-bound ATP-driven pumps and Na⁺/Ca²⁺ antiports for Ca²⁺ extrusion, but little is known about Ca²⁺ influx mechanisms into these cells. It has been shown that the administration of Ca²⁺ channel blockers in vivo strongly impairs Ca²⁺ uptake in the mineral phase during dentinogenesis in the rat; the present in vitro study is aimed at further elucidating odontoblast Ca²⁺ uptake mechanisms. Dissected rat incisor odontoblasts exhibited a pronounced fluorescence when incubated with a fluorescently-labeled (STBodipy) dihydropyridine, which is specific for voltage-gated Ca²⁺ channels of the L-type, and this binding was competitively abolished by nifedipine. As assayed by fluorescence spectrometry, odontoblast Ca²⁺ uptake was enhanced by the agonistic dihydropyridine BAYK-8644 (5 μM) as well as by plasma membrane depolarization in a high K⁺ (120 mM) medium. The Ca²⁺ uptake after depolarization was impaired by nifedipine (5 μM). When treated with the Ca²⁺-ATPase inhibitor cyclopiazonic acid (CPA; 10 μM), a nonvoltage-gated uptake of ⁴⁵Ca²⁺ was identified. This uptake was not influenced by nifedipine (20 μM) but was impaired by lanthanum ions (200 μM). A nonvoltage-gated uptake of Mn²⁺ into CPA-treated cells could be traced using the fura-2 quenching technique. This CPA-induced Ca²⁺ flux was not caused by an alteration of the plasma membrane potential, as assayed with di-8-ANEPPS. The results demonstrate that Ca²⁺ flux into dentinogenically active odontoblasts occurs through voltage-gated Ca²⁺ channels of the L-type and by nonvoltage-gated, agonist-sensitive Ca²⁺ uptake pathways. Received: 6 November 1995 / Accepted: 21 February 1996     

Managed mental health care: problems and possibilities

Case management has become an established organizational approach to mental health care. However, a recent development of case management, known as 'managed care' has received only limited attention in the UK and this has been confined to acute medical or surgical hospital care. The potential of managed care as applied to mental health care is uncertain. This paper clarifies the nature of managed care and discusses its relevance to mental health care, in particular to the care of people suffering from schizophrenia. The high incidence and heavy resource demands of this user group makes these people an ideal focus for managed care. However, there are conceptual and practical problems hindering its development and implementation, including: the variability and unpredictability of the disease process of schizophrenia; challenges of outcome measurement; and problems relating to the current organization of mental health care.     

A new method for application of force to cells via ferric oxide beads

 We describe a new method that uses straightforward physics to apply force to substrate-attached cells. In this method, collagen-coated magnetic ferric oxide beads attach to the dorsal surface of cells via receptors of the integrin family, and a magnetic field gradient is applied to produce a force. In this paper we present a complete characterization of the method in a configuration that is easy to use, in which a permanent magnet provides a fairly uniform gradient over a relatively large area. This allows a fairly uniform average force that can be controlled in magnitude, direction, and duration to be applied to a large number of cells. We show how to determine the applied force per cell by measuring the force per unit volume of magnetic bead, the distribution of bead diameters, and the distribution of beads per cell. We also show how to calculate the force per unit volume of bead in a three-dimensional region near the permanent magnet on the basis of field measurements, and present results for three of the magnets. An upward force applied to fibroblasts by this method produces a measurable time-dependent increase in attachment of cytoskeletal actin filaments to the force application points, and an increase in actin cross-linking. This is accompanied by an actin-dependent retraction of the force-induced upward movement of the dorsal surface of the cells. Received: 27 February 1997 / Received after revision: 10 August 1997 / Accepted: 1 September 1997     

Modulation of infection-induced inflammation and locomotive deficit and longevity in senescence-accelerated mice-prone (SAMP8) model by the oligomerized polyphenol Oligonol.

Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection.     

视交叉后损害的临床与图形视觉诱发电位分析

图形视觉诱发电位(P—VEP)是眼接受图形的刺激时,视路及大脑皮质枕区所产生的一系列电位变化。在视交叉后病变的诊断,病情估计及预后推测中有比较肯定的价值。 本文对17例视交叉后损害的病人进行分析。发现视交叉后病变以视皮质损害为主,表现为视物模糊,视力下降,视野改变。P—VEP检查的异常率与病变部位大小及病变性质有关。同时检查半视野刺激有助于提高阳性率。     

Chromatic pattern-reversal electroretinograms (ChPERGs) are spared in multiple system atrophy compared with Parkinson’s disease

Abstract Idiopathic Parkinson’s disease (IPD) patients have abnormal visual evoked potentials (VEPs) and pattern electroretinograms (PERGs), attributed to dopaminergic transmission deficiency in visual pathway, probably the retina. VEP abnormalities are not reported in multiple system atrophy (MSA). The aim of this study was to investigate and compare chromatic (Ch) red-green (R-G) and blue-yellow (B-Y), and luminance yellow-black (Y-Bk) PERGs in patients with MSA and IPD. We investigated 6 MSA patients (mean age: 62±7.4 years) not undergoing any pharmacological treatment, as well as 12 early IPD patients (mean age: 60.1±8.3 years) and 12 age-matched normal observers. ChPERGs were recorded monocularly in response to full-field equiluminant R-G, B-Y and Y-Bk horizontal gratings. In MSA only responses to R-G stimuli showed minimal insignificant changes (slight but not significant amplitude reduction without any significant latency delay); no significant abnormality was detected for B-Y and luminance Y-Bk stimuli. By contrast, in IPD all responses were reduced in amplitude and delayed in latency, above all for B-Y stimuli. Present data indicate that both chromatic and achromatic PERGs are virtually unaffected in MSA, whereas in early IPD they are clearly impaired, suggesting different pathogenic retinal mechanisms and a useful simple tool for distinguishing MSA from IPD.     

经食道心房程序调搏检测房室结双径路——附23例检查报告

本文通过食道心房程序调搏检测出典型房室结双径路23例,其中12例诱发室上性心动过速(占52%);占17例有心动过速发作史者的70.6%。本文着重分析了房室结双径路与室上性心动过速的关系。