Early coping experience and later aversive conditioning in cats

Kittens were given differential early experience in order to compare an objective coping behavior with the result of an inescapable aversive experience. Separate groups of kittens were treated in a shock motivated runway task at either 4 or 12 weeks of age, by allowing one member of a weight matched sibling pair to acquire an escape behavior, while the other member was confined; a third subject served as a handled control. Escape behavior was significantly different for 4 and 12 week old subjects, since the older kittens reached a running asymptote within the first few shock trials. At 6 months of age, the subjects were tested for effects of differential early treatment; heart rate, respiration rate and amplitude, and somatic activity were measured during classical conditioning. While all groups gave evidence of acquisition in one or more response measures, only a potentiated heart rate response in 4 week kittens could be related to early experience. Heart rate did not differentiate escaping kittens from confined ones. Rather, heart rate was related to early treatment with shock, perhaps reflecting an increased tendency to react with a passive defensive response.     

Adrenergic,purinergic, and endothelial mediators and modulators of norepinephrine-induced mesenteric autoregulatory escape

We evaluated the effects of potential factors in autoregulatory escape from norepinephrine-induced vasoconstriction in rat anterior mesenteric artery. We determined mesenteric artery blood flow velocity with a pulsed Doppler, sonic flowmeter, and systemic arterial blood pressure with a transducer. A 4-min norepinephrine infusion (0.125–1.0 × 10^–8 M/min) intravenously evoked a dose-dependent, initial vasoconstriction that was followed by rapid escape of blood flow toward or above the control value during sustained norepinephrine administration. Neonatal capsaicin treatment enhanced vasoconstrictor responses to norepinephrine but failed to affect escape parameters. Propranolol decreased norepinephrine-induced escape dose dependently. Adenosine deaminase attenuated escape, and the combination of this enzyme plus propranolol nearly abolished escape from norepinephrine-induced vasoconstriction. Methylene blue also diminished autoregulatory escape. These findings suggest that norepinephrine-induced autoregulatory escape involves simultaneous -adrenoceptor, purinergic, and endothelial mediation. Norepinephrine-evoked mesenteric vasoconstriction appears to involve predominantly ₂-adrenoceptors and is modulated by peptidergic sensory nerves and adenosine.NIH grant number supporting these studies: USPHS # DK37050.     

Differential effects of anxiogenic central and peripheral benzodiazepine receptor ligands in tests of learning and memory

Previous research has demonstrated that low doses of anxiogenic central benzodiazepine receptor (CBR) ligands, the beta-carbolines, improve performance in various learning and memory tests in animals if administered prior to training. The present experiments compared the effect of a beta-carboline (FG 7142) with that of a pharmacologically distinct anxiogenic compound, a peripheral benzodiazepine receptor (PBR) ligand, 4-chlorodiazepam (Ro5-4864), in two tests of learning and memory in rats. As expected, FG 7142 significantly improved performance in a passive avoidance test. Ro5-4864 was without effect. In a shuttlebox escape test, Ro5-4864 significantly impaired performance while FG 7142 had no effect. The effect of Ro5-4864 was antagonized by the specific peripheral benzodiazepine receptor antagonist, PK 11195. These results indicate that the differential impact of CBR and PBR anxiogenic ligands on performance in aversively-motivated learning tests may be a reflection of their distinct pharmacologies.     

原发性高血压患者醛固酮逃逸现象与左心室肥厚的关系

目的探讨原发性高血压(EH)患者使用血管紧张素转换酶抑制剂(ACEI)依那普利后并发的醛固酮逃逸及与左心室肥厚(LVH)的关系,并观察ACEI联合使用螺内酯后对醛固酮逃逸和LVH的效果。方法65例EH患者分为左心室肥厚组(LVH组)和非左心室肥厚组(NLVH组),使用依那普利。分别于治疗前及治疗后1、3、6个月采血检测血管紧张素Ⅱ(AngⅡ)、醛固酮(Ald)浓度,并用超声心动图测定左心室重量指数(LVMI)。根据3个月时的Ald浓度,判断有无醛固酮逃逸,对有醛固酮逃逸者,联合用螺内酯3个月,观察效果。结果依那普利治疗后1个月,AngⅡ、Ald与治疗前相比均下降,但3个月时,AngⅡ有所升高,Ald明显增高,65例中有28例并发醛固酮逃逸。治疗前LVH组的Ald明显高于NLVH组,LVMI与Ald呈明显的正相关;LVH组治疗3个月,无醛固酮逃逸者的LVMI与治疗前比较有显著下降,有醛固酮逃逸者LVMI变化不显著。结论EH患者长期使用ACEI后会出现醛固酮逃逸现象,Ald与EH合并的LVH有明显的相关性,ACEI能逆转EH所合并的LVH,但醛固酮逃逸能阻碍ACEI对LVH的逆转作用,ACEI联合使用螺内酯可能会改善醛固酮逃逸。     

枸杞多糖对荷瘤小鼠免疫抑制因子VEGF、TGF-β1水平的影响

目的观察枸杞多糖对荷瘤机体内免疫逃逸有关因子的干预作用.方法采用 H22荷瘤小鼠,用枸杞多糖连续灌胃治疗两周后,观察胸腺、肿瘤重量,计算胸腺指数及肿瘤生长抑制率;ELISA双抗体夹心法检测各组血清中血管内皮细胞生长因子(VEGF)、转化生长因子β1(TGF-β1)水平.结果枸杞多糖可明显抑制荷瘤小鼠肿瘤的生长,对小鼠的胸腺具有一定的保护作用,可下调血清中 VEGF、TGF-β1水平.结论枸杞多糖的抗肿瘤作用与抑制肿瘤机体 VEGF、TGF-β1因子的分泌、干预机体的免疫逃逸状态有关.     

Patterns of Relapse or Progression After Bortezomib-Based Salvage Therapy in Patients With Relapsed/Refractory Multiple Myeloma

IntroductionBortezomib-based therapy is commonly used in treatment for relapsed or refractory multiple myeloma (MM). Unfortunately, many patients show relapse or progression in heterogeneous patterns.Patients and MethodsIn this study, we retrospectively evaluated patterns of relapse or progression after bortezomib-based salvage therapy in patients with MM and analyzed prognostic significance according to patterns of relapse or progression. One hundred forty-eight patients were treated with bortezomib-based therapy between November 2004 and April 2012. Of these patients, 104 (70.3%) patients relapsed or progressed after bortezomib-based salvage therapy. We divided the patterns of relapse or progression to the 2 groups: (1) the isoform relapse or progression (group A) in 89 (85.6%) patients as disease findings at initiation of bortezomib-based therapy; and (2) transformed relapse or progression (group B) in 15 (14.4%) patients (plasmacytoma, n = 7; light chain escape, n = 6; and plasma cell leukemia, n = 2) different from initial disease findings.ResultsMedian overall survival in group A and group B were 32.7 months (95% confidence interval [CI], 21.3-44.1) and 10.7 months (95% CI, 2.0-19.4) (P < .001), respectively.ConclusionMM patients who relapsed or progressed as the transformed pattern for bortezomib-based salvage therapy have an extremely poor prognosis and might require new innovative approaches.     

Tumor‐educated myeloid cells: impact the micro‐ and macroenvironment

Immune escape mechanisms of cancers include some of the mechanisms normally used for immune homeostasis, particular those preventing autoimmunity; one of these is the polarisation of myeloid cells. Thereby, tumors, i.e. the cancerous and stromal cells, also condition distant sites like spleen and bone marrow via soluble factors and membrane vesicles such as exosomes in order to create a tumor‐educated macroenvironment. Albeit these mechanisms are currently in the focus of (tumor‐)immunologic research, the first evidence had been published almost 40 years ago. One of these early reports will be discussed here.     

Hyaluronan-based delivery of therapeutic oligonucleotides for treatment of human diseases

Introduction: Oligonucleotide therapeutics such as antisense oligonucleotides and siRNA requires chemical modifications and nano-sized carriers to circumvent stability problems in vivo, to reach target tissues, and to overcome tissue and cellular barriers. Hyaluronic acid (HA), already utilized in drug delivery and tissue engineering, possess properties that are useful to solve these problems and achieve full potential of oligonucleotide therapeutics.

Areas covered: Complexes of oligonucleotide therapeutics with HA are discussed in terms of interactions providing the complexes formation and genes targeted by the therapeutics to cure diseases such as cancer, atherosclerosis, liver cirrhosis, and inflammation. The achieved therapeutic effects are rationalized as consequences of biodistribution, cell internalization and endosomal escape provided by HA.

Expert opinion: Design of electrostatic, coordination, and hydrophobic interactions as well as covalent conjugation between oligonucleotide drugs, HA macromolecules and intermediate ligands are crucial for carrier–cargo association and dissociation under different conditions to impart oligonucleotides stability in vivo, their accumulation in diseased organs, cellular uptake, and dissociation in cytoplasm intact. These are the delivery factors that provides eventual complex formation of oligonucleotide therapeutics with their mRNA, microRNA, or protein targets. Elucidation of the impact of structural parameters of oligonucleotide/HA complexes on their therapeutic effect in vivo is important for the future rational design of the delivery agents.