人颅骨电阻抗频率特性及其与解剖结构关系研究

在电阻抗断层成像(EIT)技术应用于脑部成像的研究中，颅骨的电阻抗对驱动电流的屏蔽效应非常严重，严重影响了成像效果(特别是中心区域)。本研究采用离体人颅骨，二电极法，用频响分析仪(Solartron 1255B)经电阻抗接口(Solartron 1294)，在0．1Hz～1MHz频率范围内进行测量，描记出颅骨电阻抗频响特性曲线，初步观察了颅骨电阻抗随时间变化的趋势，研究了颅骨解剖结构同其电阻抗之间的关系。结果表明：颅骨电阻抗幅值随时间明显增大；其特征频率应在10KHz附近，颅骨组织的解剖结构对颅骨电阻抗有重要的影响，含有板障层的厚颅骨由于颅骨内、外板中富含毛细血管的原因，其电阻抗较不含板障层的薄颅骨电阻抗小。本研究结果为解决颅骨高阻抗的屏蔽效应问题提供了可能的参考和依据。     

职业驾驶员心理应激及其相关变量分析

目的 :了解职业驾驶员心理应激状况及相关因素 ,为减少事故的发生提供资料。方法 :采用LES、应对、成人内外控制、SSRS、EPQ、SCL -90等量表对 2 40名职业驾驶员进行测试。结果 :①驾驶员的主要应激源是工作学习问题、家庭有关问题 ;应对方式上 ,更趋向于积极应对 ;社会支持上 ,主观支持分明显高于客观支持分 ;在心理控制感上 ,明显趋于外控 ;EPQ得分与普通人群相比 ,E分较高 ,N分较低 ;SCL -90各因子分均值与全国常模相比 ,除躯体化、强迫、焦虑等项因子均值较高外 ,其他无显著差异。②事故组与安全组驾驶员在生活事件、相关变量、应激反应上 ,均存在显著差异。③行车事故与应激性生活事件呈正相关 (P <0 0 1)、与EPQ -N ,SCL -90诸因子呈负相关 (P <0 0 1)。结论 :生活事件引起的情绪应激 ,与驾驶操作、交通违章和事故发生有一定相关关系。     

银杏叶制剂和丹参对急性肾衰兔肾皮质局部血流量的影响

目的探讨急性肾功能衰竭(acute renal failure,ARF)兔肾皮质局部血流量(regional renalblood flow,rRBF)与血液流变学的关系,以及银杏叶制剂(Ginkgo Bilobal Extraction,GbE)、丹参对其的影响.方法用50%的甘油10 ml/kg行兔后肢肌肉加压注射,建立ARF动物模型,观察血液流变学、rRBF的变化,并给予GbE、丹参注射液对比观察.结果 ARF组血液流变学指标明显异常,rRBF明显下降.ηb、ηb、EAI、HCT等与rRBF呈明显负相关(P均＜0.05).GbE组、丹参组动物血液流变学、rRBF等指标明显改善.结论 ARF时血液流变特性恶化和肾局部微循环障碍可能是造成rRBF下降的直接原因之一.GbE、丹参对甘油所致ARF家兔的血液流变特性及肾组织缺血性损害有明显的保护作用.     

Dendritic spines in the posterodorsal medial amygdala after restraint stress and ageing in rats

Several evidences suggest that the posterodorsal medial amygdala (MePD) can be a relevant part of the rat neural circuitry for the regulation of hypothalamic neuroendocrine secretion and for ontogenetically different behavioral displays. The dendritic spine density of Golgi-impregnated neurons from the MePD was evaluated in young rats following acute or chronic restraint stress and in aged animals (24 months old). Compared to the control group, a single 1 h restraint stress session promoted a decreased spine density (p < 0.01) whereas a single 6 h restraint stress session or daily 6-h restraint sessions for 28 consecutive days did not lead to the same effect (p > 0.05). Aged rats showed no difference in this dendritic spine parameter when compared to young adults (p > 0.05). These results indicate that short-term stress (1 h) can affect MePD dendritic spines and that neural plasticity is involved with adaptive responses onwards in restrained rats. On the other hand, brain structural modifications related with ageing appear not to influence the number of certain postsynaptic sites in the MePD of rats.     

汶川地震亲历者心理健康状况调查

目的:研究汶川地震后受灾群众的心理健康状况及影响因素。方法:采用事件影响量表修订版(IES-R)等测量工具,对灾后一月内四川省什邡地区及转入本院的受灾群众共342人进行评估。结果:灾后一月内PTSD症状的发生率为45.9%,女性明显高于男性;两个群体PTSD症状的发生率差异不明显,但什邡地区症状程度较重,消极应对、脱离灾后环境等因素是PTSD症状的影响因素。结论:地震后受灾人群,PTSD症状发生率较高,其中女性群体应受到更多的关注。     

Cell-mediated immune responses to mycobacterial antigens in patients with pulmonary tuberculosis and HIV infection

Lymphocyte proliferation and cytokine responses induced by a panel of mycobacterial antigens were compared in Portuguese donors with pulmonary tuberculosis (TB) with or without HIV co-infection, HIV⁺ patients and healthy Mantoux-positive controls. Control donors showed stronger proliferative responses than any of the patient groups, with secreted antigens (Mycobacterium tuberculosis (Mtb) 30 kD and short-term culture filtrate proteins (ST-CFP)), purified protein derivative (PPD) and Mtb H37Rv Sonicate (MtbS) inducing the strongest proliferation. Patients with pulmonary TB showed lower proliferation to PPD or to the 30-kD antigen. Responses to all the antigens (PPD, ST-CFP, MtbS, 70 kD, 65 kD, 38 kD, 30 kD and 10 kD) were higher in TB/HIV patients with CD4 counts 200 CD4⁺ T cells/mm³ compared with HIV alone (CD4 200 T cells/mm³), but were lost in both TB/HIV and HIV patients when CD4 counts fell below 200 T cells/mm³. Measurements of interferon-gamma (IFN-γ) in culture supernatants revealed that PPD, 30 kD, MtbS and ST-CFP induced the strongest Th1 response. Analysis of mRNA for IFN-γ, IL-4 and IL-10 confirmed that IFN-γ production was maintained in patients with pulmonary TB without any concomitant increase in IL-4 or IL-10 mRNA expression, although expression of IL-10 mRNA was increased if HIV infection was present. These results reveal that IFN-γ production is retained in pulmonary TB patients to a broad range of mycobacterial antigens, and that no switch to IL-4 production is seen even with HIV infection. Secreted antigens, and in particular ST-CFP, were the best inducers of IFN-γ secretion, confirming their role in protective responses to Mtb.     

Effect of heat and cold factors on amylolytic and invertase activity of the small intestine in growing rats

Acute experiments on young rats showed that exposure to heat (40–41°C) and cold (5–6°C) and injections of ACTH (4 units/100 g body weight per injection) during the first week of life led to a sharp decrease in total amylolytic and invertase activity of homogenates and everted segments of the small intestine of the animals. The inhibition of intestinal function continued throughout the next 2 weeks of life.Laboratory of the Physiology of Digestion, Institute of Physiology, Academy of Sciences of the Uzbek SSR, Tashkent. (Presented by Academician V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 10, pp. 1213–1215, October, 1976.     

Integrity of the blood-cerebrospinal fluid barrier in early Parkinson's disease

Dysfunction of the blood–cerebrospinal fluid barrier (BCB) has been implicated in the pathogenesis of Parkinson's disease (PD) and other neurodegenerative disorders. Therefore, we assayed serum and cerebrospinal fluid (CSF) from 30 parkinsonian patients and 30 controls for concentrations of albumin and IgG. The CSF/serum ratio for albumin (AQ), IgG (GQ), IgG-index as well as determination of oligoclonal bands were used to evaluate BCB function and to quantify humoral immune response within the central nervous system (CNS). Levels of AQ, GQ and IgG-index did not significantly differ in both groups. We found no dysfunction of the blood–CSF barrier or signs of local synthesis of IgG in the central nervous system of parkinsonian patients. Our data do not support the hypothesis of a dysfunctional BCB that contributes to pathophysiological mechanisms underlying PD.     

The Leishmania infantum acidic ribosomal protein LiP2a induces a prominent humoral response in vivo and stimulates cell proliferation in vitro and interferon-gamma (IFN-gamma) production by murine splenocytes

The acidic ribosomal proteins of the protozoan parasite Leishmania infantum have been described as prominent antigens during both human and canine visceral leishmaniasis. In this study we present data showing that the intraperitoneal administration in BALB/c mice of the Leishmania LiP2a protein, in the absence of any added adjuvants, elicited a strong humoral response as an indication that the protein is a potent immunogen. Despite the evolutionary conservation of the acidic ribosomal proteins, the antibody response was found to be specific for the Leishmania protein. Another remarkable finding was the observation that the LiP2a protein stimulates the in vitro proliferation of splenocytes from either LiP2a-immunized or naive BALB/c mice. Since similar proliferative indices were observed in T cell-enriched cultures, it is likely that the LiP2a stimulating activity is due mainly to T lymphocyte expansion. Also, the stimulatory effect was demonstrated to be antigen-specific, since the proliferation was abrogated by the presence of anti-LiP2a antibodies. Interestingly, the LiP2a protein stimulated the production of substantial amounts of IFN-gamma in cultured splenocytes from LiP2a-immunized mice. Our data indicate therefore that the immunostimulatory properties shown by this antigen should be taken into account when developing therapeutic and prophylactic vaccines against leishmaniasis.     

NADPH oxidase inhibition improves neurological outcomes in surgically-induced brain injury

Neurosurgical procedures can result in brain injury by various means including direct trauma, hemorrhage, retractor stretch, and electrocautery. This surgically-induced brain injury (SBI) can cause post-operative complications such as brain edema. By creating a mouse model of SBI, we tested whether NADPH oxidase, an important reactive oxygen species producing enzyme, is involved in SBI using transgenic mice lacking gp91^phox subunit of NADPH oxidase (gp91^phox KO) and apocynin, a specific inhibitor of NADPH oxidase. Neurological function and brain edema were evaluated at 24 h post-SBI in gp91^phox KO and wild-type littermates grouped into SBI and sham-surgery groups. Alternatively, mice were grouped into vehicle- and apocynin-treated (5 mg/kg, i.p. 30 min before SBI) groups. Oxidative stress indicated by lipid peroxidation (LPO) was measured at 3 and 24 h post-SBI. The gp91^phox KO mice, but not the apocynin-treated mice showed significantly improved neurological scores. Brain edema was observed in both gp91^phox KO and wild-type groups after SBI; however, there was no significant difference between these two groups. Brain edema was also not affected by apocynin-pretreatment. LPO levels were significantly higher in SBI group in both gp91^phox KO and wild-type groups as compared to sham group. A trend, although without statistical significance, was noted towards attenuation of LPO in the gp91^phox KO animals as compared to wild-type group. LPO levels were significantly attenuated at 3 h post-SBI by apocynin-pretreatment but not at 24 h post-SBI. These results suggest that chronic and acute inhibition of NADPH oxidase activity does not reduce brain edema after SBI. Long-term inhibition of NADPH oxidase, however improves neurological functions after SBI.