L-精氨酸对肺动脉高压肉鸡肺小动脉平滑肌细胞凋亡的影响

将240羽14日龄艾维茵-2000商品代肉鸡于14d时随机等分为常温对照组（NT组），低温组（LT组）和低温加L-精氨酸组（LA），白14d起，LT和LA组舍内温度从28℃以1～2℃／d的速度下降，至21d降至12～14℃，并维持到试验结束。此外，LA组自14d起在饲料中按100mg／kg剂量添加L—Arg，直至试验结束。记录肺动脉高压综合征（PHS）发病率，并分别于24、32、39和45d测定右心室／全心室质量比（RV／TV）、血浆NO、肺小动脉管壁面积／管总面积（WA／TA）和平均中膜厚度（mMTPA），并用原位缺口末端标记法（TUNEL法）对肺小动脉凋亡平滑肌细胞进行染色和计数。结果：LT组肉鸡PHS发病率、RV／TV、mMTPA和WA／TA值较NT组升高（P〈0．05）；LA组肉鸡PHS发病率较LT组降低（P〈0．05），mMTPA和WA／TA值与LT组相比呈下降趋势，在32d时显著降低（P〈0．05）；LT组血浆N0浓度总体上与NT组差异不显著（P〉0．05），仅在39d时降低（P〈0．05），而LA组血浆N0浓度自32d时起较NT和LT组显著升高（P〈0．05）；LA组肉鸡肺小动脉平滑肌凋亡细胞百分率较NT组和LT组均显著升高（P〈0.05），但LT组与NT组之间相比无显著差异（P〉0．05）。上述结果表明，L-Arg／NO通过促进肺小动脉平滑肌细胞凋亡，从而在一定程度上抑制了肺血管重构的形成。     

Effects of three kinds of calcium activator on the proliferation of cultured vascular smooth muscle cells in rats

AIM: To investigate the effects of intracellular free calcium ([Ca²⁺]i) from different resources on the proliferation mediated by mitogen activated protein kinase (MAPK) in vascular smooth muscle cells (VSMCs). METHODS: Cultured VSMCs were used in all experiments. Calcium influx was stimulated by angiotension Ⅱ(Ang Ⅱ). The release of intracellular calcium stores was induced by inositol trisphosphate (IP₃) and ryanodine (RY). MAPK activity was measured by [γ-³²P]-ATP incorporation MAPK protein expression by western blot, VSMCs proliferation by [³H]-Leucine ([³H]-Leu) and [³H]-Thymidine ([³H]-TdR) incorporation. RESULTS: Compared to the control VSMCs, Ang Ⅱ, IP₃ and RY significantly increased [Ca²⁺]i concentration activity of MAPK and its protein content in VSMCs. The promotion of [³H]-Leu and [³H]-TdR incorporation in VSMCs was also observed (P<0.01). CONCLUSION: The study indicated that calcium activator-induced increase in the activity and protein content of MAPK was involved in the proliferation of VSMCs, which was closely related to the [Ca²⁺]i concentration but independent to its origin.     

An experimental exploration of focal inflammatory response in cerebral ischemic foci in the rat

AIM: To study the pathological relationship of vascular cell adhesion molecule-1 (VCAM-1) expression and monocyte/macrophage infiltration with focal brain ischemia. METHODS: Immunohistochemical technique and focal brain ischemia/reperfusion model were used in the study in order to explore profiles and time-course of VCAM-1 expression and monocyte macrophage (ED2 positive cell) infiltration in ischemic rat brain. RESULTS: VCAM-1 was up-regulated in microvascular endothelial cells in ischemic cortex at 1h postischemia, and continuously expressed during the time of reperfusion. ED2 positive cells infiltrated into ischemic cortex at 1h iscehmia/ 2h reperfusion and then ED2 positive cells increased gradually with the time of reperfusion, ED2 positive cell infiltration showed apparently relationship with VCAM-1 expression, and both of them exhibited the some changes of time-dependence. CONCLUSION: Cerebral ischemia induced VCAM-1 expression and ED2 positive cell infiltration and VCAM-1 may regulate the recruitment of ED2 positive cells in the ischemic brain region. The results suggested that VCAM-1 and ED2 positive cells may be participated in the pathogenesis of cerebral ischemic injury.     

Evaluation of a percutaneously controlled hydraulic occluder in a rat model of gradual venous occlusion

OBJECTIVE: To evaluate the efficacy of a percutaneously controlled hydraulic occluder (HO) in a rat model of gradual venous occlusion. STUDY DESIGN: Experimental study. ANIMALS: Ten male Sprague-Dawley rats. METHODS: HOs and perivascular transit time ultrasound flow probes were applied to the caudal vena cava (CVC). Occluders in group I rats (n=6) were gradually attenuated over 8 weeks, whereas occluders in group II rats (n=4) were not attenuated. Vena caval blood flow measurements were performed weekly in all rats for 8 weeks. After euthanasia, the CVC was evaluated grossly and by histopathology. RESULTS: Premature occlusion of the vena cava occurred during the 1st week in 3 rats (1 in group I, 2 in group II) because of kinking of the vena cava between the HO and the flow probe. For the remaining rats, mean blood flow in group I decreased significantly from 40.71 mL/min/kg at baseline to 4.68 mL/min/kg at 8 weeks (P=.0094, power=0.91). Group II rats maintained vena caval blood flow at all times during the study. Complete occlusion of the vena cava was confirmed at necropsy in all group I rats. CONCLUSIONS: Gradual occlusion of the CVC of rats was achieved with HOs over 8 weeks. This model is limited by the size of the experimental animals and comparatively large implants. CLINICAL RELEVANCE: HOs may provide a method for gradual occlusion of congenital portosystemic shunts.     

籼粳稻维管束性状关系研究

选用5份粳稻和4份籼稻材料,对不同品种水稻维管束的数量进行比较研究,同时结合程氏指数调查,探讨了籼稻和粳稻之间的维管束差异。结果表明:籼稻穗颈维管束数明显高于粳稻,其大维管束效率较高;籼稻的穗颈维管束数与穗一次枝梗数之比(V/R)也显著高于粳稻,大小维管束比也较高。籼稻程氏打分均较低,而粳稻的较高。     

心脉隆注射液对动脉粥样硬化大鼠血管内皮细胞的保护作用

目的探讨心脉隆注射液对动脉粥样硬化（AS）大鼠血管内皮细胞的保护作用.方法采用高脂饲料加维生素D3喂养8周的方法建立动脉粥样硬化大鼠的模型.将大鼠随机分为正常组、模型组、辛伐他汀组、心脉隆治疗组四组,高脂饲料喂养8周后取血测一氧化氮（NO）、内皮素（ET）、前列环素（PGI2）和血栓素（TXA2）的含量.结果心脉隆注射液给药8周后能明显的升高AS大鼠血清NO和血浆PGI2水平（P〈0.05）,显著降低血浆ET的含量（P〈0.05）.结论心脉隆注射液能保护AS大鼠血管内皮细胞,减轻动脉粥样硬化的进程,对动脉粥样硬化有治疗作用.     

Ultrasonographic identification of vascular invasion by adrenal tumors in dogs

Adrenalectomy is the treatment of choice for adrenal tumors that are producing adverse clinical signs. Surgical planning prior to adrenalectomy is aided by identifying tumors with invasion into adjacent vessels or the presence of a tumor thrombus extending into the caudal vena cava. In this paper, we evaluated the sensitivity and specificity of ultrasound in determining if vascular invasion or tumor thrombus is present. Thirty-four dogs with 36 adrenal tumors were reviewed retrospectively. Overall, 36% of tumors had vascular invasion. Abdominal ultrasound was 100% sensitive and 96% specific in identifying the presence of a tumor thrombus in the caudal vena cava. The sensitivity and specificity was 76% and 96%, respectively, when all forms of vascular invasion were evaluated and included patients with vascular wall invasion without concurrent thrombus. Abdominal ultrasound is a good screening tool for identifying vascular invasion or tumor thrombus associated with adrenal tumors in dogs.     

高光谱荧光示踪无损检测瓜类作物嫁接苗愈合状态

为了减少瓜类嫁接苗的愈合管理时间,实现快速准确判别嫁接苗早期愈合状态,促进嫁接苗规模化生产及育苗产业发展。该研究制备了氮硫掺杂碳点,以该碳点为荧光示踪材料,以西瓜嫁接苗为研究对象,利用高光谱荧光成像方法,探究了西瓜嫁接苗早期愈合状态无损检测的高光谱荧光示踪成像方法。高光谱荧光示踪图像及光谱分析结果表明,利用氮硫掺杂碳点进行荧光示踪,通过高光谱成像仪对瓜类作物早期愈合状态高通量表型的鉴定,能快速、自动、无损地获取嫁接苗愈合的情况。同时,通过氮硫掺杂碳点处理后第12天,处理组的西瓜嫁接苗相较于对照组,根系增长量提升了78.7%,叶面积增长量提升了61.4%。因此,该研究方法可以提早判别嫁接苗的愈合连通,促使瓜类嫁接苗提早移栽,并且氮硫掺杂碳点处理可以促进嫁接苗叶面积和根系的生长,达到种苗壮苗的作用。     

Computed tomographic assessment of vascular invasion and resectability of mediastinal masses in dogs and a cat

AIMS: To assess the sensitivity of non-angiographic contrast-enhanced computed tomography (CT) to determine the presence of vascular invasion of cranial mediastinal masses in dogs and a cat, and to evaluate the association between vascular invasion and peri-operative mortality.

METHODS: A retrospective study was conducted on 25 dogs and one cat. CT scans were completed with slices ranging from 2 to 10 mm. CT images were evaluated by a board-certifi ed radiologist blinded to previous diagnoses and surgical fi ndings. Each CT study was evaluated for vascular invasion, defi ned as disruption of the vessel wall and extension of the mass into the vessel lumen. Data retrieved from the surgery reports included surgical approach, whether vascular invasion was present, the surgeon's decision on operability, and post-operative complications.

RESULTS: Computed tomographic evaluation revealed 25/26 masses had no evidence of vascular invasion. During surgical exploration, 10/26 masses were found to invade major regional vasculature; the cranial vena cava (CVC) was the vessel most commonly invaded (7/10 animals), and 4/7 (57%) patients with invasion of the CVC were euthanised or died in the perioperative period, from surgical or disease-related problems, which was signifi cantly higher than patients without vascular invasion (p=0.045).

CONCLUSIONS: Non-angiographic contrast-enhanced CT was signifi cantly less sensitive for detecting vascular invasion of cranial mediastinal masses when compared with surgical evaluation. If the CVC was invaded by a tumour there was a signifi cant risk of death peri-operatively when compared with non-invasive cases.

CLINICAL RELEVANCE: Due to the signifi cantly higher mortality risk associated with invasion of the CVC, a more sensitive method than CT should be investigated to determine vascular invasion of mediastinal masses pre-operatively.     

Autologous point‐of‐care cellular therapies variably induce equine mesenchymal stem cell migration,proliferation and cytokine expression

Reasons for performing study: Autologous cellular therapy products including adipose‐derived stromal vascular fraction (SVF), bone marrow mononuclear cells (BMMNs), cord blood mononuclear cells (CBMNs) and platelet rich plasma are options for treatment of acute orthopaedic lesions while mesenchymal stem cells (MSCs) are culture expanded. These products may contribute to healing by secreting matrix proteins or growth factors, but they may also act on endogenous MSCs to facilitate healing. Objectives: To determine the effects of cell therapy products on MSCs function in vitro. The hypothesis was that cell therapy products promote MSCs functions including proliferation, migration and mediator release. Methods: Fat, bone marrow (BM), cord blood and platelets were obtained from 6 Quarter Horses. The BM‐MSCs and their autologous cell therapy products were co‐incubated in transwells. Mesenchymal stem cells proliferation, migration, gene expression and cytokine concentrations were determined. Results: All cell therapy products increased MSCs proliferation, but SVF induced significantly more proliferation than any other product. Also SVF elicited more MSCs chemotaxis and, along with BMMNs, significantly more MSCs chemoinvasion. Cord blood mononuclear cells stimulated MSCs to produce high concentrations of interleukin‐6 (IL‐6), transforming growth factor‐β1 (TGF‐β1), and prostaglandin E₂ (PGE₂). Stromal vascular fraction and platelet lysate did not stimulate MSCs but SVF and platelet lysate themselves contained high concentrations of PGE₂ and IL‐6 (SVF) and TGF‐β1 (platelet lysate). Conclusions: Autologous cell products variably stimulate MSCs functions with 2 primary patterns apparent. Products either contained preformed mediators that may have intrinsic healing function, or products stimulated MSCs to secrete mediators. Potential relevance: The specific clinical indications for these products may differ to include administration as a sole treatment modality prior to MSCs injection for intrinsic cell and cytokine activity (i.e. SVF) or administration concurrently with MSCs to activate MSCs for treatment of chronic lesions (i.e. CBMNs).