Cerebral Computed Tomography Scan Demonstrating Ischemic Stroke in a Filly After Intravenous Antibiotic Administration

Performing a brain computerized tomography scan (CT scan) on a foal requires specific equipment and anesthesia for large animals. However, the information obtained may demonstrate lesions responsible for the neurological deficits. Especially, CT scan findings may help to understand a mechanism of cerebral ischemia. Indeed, categories of cerebral ischemia are divided in three types: territorial infarctions (downstream of the territory of an artery), watershed infarctions (slow-flow at the junction of two arterial territories), and lacunar infarctions (small-vessel occlusions). Hypersensitivity reactions and type I anaphylactic IgE antibody reactions are severe potential adverse effects of sulfonamide administration, which occur in about three percent of cases. In horses, anaphylaxis is often clinically expressed as hypotension and collapse. Cardiovascular collapse may lead to multiorgan slow-flow leading to infarction with multiorgan failure and death. We report the case of a filly that suffered a presumed watershed cerebral infarction after antibiotic injection, indicated on a brain CT scan. This was attributed to a cerebral slow-flow during cardiovascular collapse, at the posterior junction of the right cerebral arteries. No abnormalities were initially identified on the CT scan; however, a review of the imaging by a radiologist specialized in cerebrovascular diseases detected a limited right occipital cortico-subcortical lesion in the visual cortex, interpreted as an ischemic scar in the watershed area related to hemodynamic infarction. This case highlights that detection of brain lesions by CT scan might require specialized knowledge and careful reading for interpretation particularly in the case of limited lesions.     

列当(Orobanche spp. and Phelipanche spp.)种子的采集与预处理方法

列当(Orobanche spp.and Phelipanche spp.)是一种在世界范围内危害严重的根寄生杂草,防除列当的研究也越来越多。正确地采集和预培养列当种子是获得正确防除列当研究结果的前提。列出了大田正确采集列当种子的方法,以及对采集到的种子进行过筛提纯、加洗洁精和吐温20清洗后,再表面消毒和预培养,并通过发芽试验检验此方法的可行性。结果表明,经过处理的向日葵列当、瓜列当种子的发芽率最高分别为54.4%、59.1%。此方法可以应用于列当的采集和预处理过程中,可为列当研究和防除提供参考。     

Phenotypic changes in progenies of northern clones of Picea abies (L.) Karst. grown in a southern seed orchard

Results are presented from three different field trials comparing controlled crossed materials of Norway spruce from the southern seed orchard at Lyngdal (58° N) with open‐pollinated progenies from the same mother trees standing in the northern natural forest (63–66° N). The seed orchard progenies flushed consistently later in the spring, terminated leader shoot growth later in the summer, had higher frequencies of lammas shoots, were delayed in lignification during autumn, and were 15% taller at age seven years from seed. The difference between the orchard‐ and the natural stand material appeared to be permanent from age four to age seven. It is suspected that the non‐native environment in the seed orchard could affect the genotypic performance of the seed orchard progenies.     

Effects of contrasting fertilization and moisture regimes on biomass,nutrients, and water relations of container grown red pine seedlings

Red pine seedlings were grown for 16 weeks under contrasting fertilizat (conventional, exponential) and moisture (wet, moist, dry) regimes to assess preconditioning effects of treatments on biomass production, nutrient uptake and allocation, and water relations. Growth, nutrient status, and water relations were affected more by moisture availability than by fertilization regime. Exponential fertilization under limited irrigation lowered shoot/root mass ratio, increased root nutrient reserves, and enhanced drought avoidance compared to conventional fertilization regimes. Drought treatments decreased nutrient uptake in the shoots of both fertilization regimes by 24%, but increased nutrient accumulation in the roots by 39% in the exponential regime compared to 17% in the conventional. These results may explain improved outplanting performance noted for exponentially fertilized container stock.     

降钙素基因相关肽预适应心肌保护作用的实验研究

目的观察降钙素基因相关肽(CGRP)预适应在整体大鼠心肌缺血/再灌注损伤中的作用并探讨CGRP能否诱导延迟性预适应效应。方法50只SD大鼠随机平均分为5组。所有动物均接受1h缺血/2h再灌注处理,A组于术前24h及术前分别静脉注射CGRP10μg/kg;B组于术前静脉注射CGRP10μg/kg;C组于术前24h静脉注射CGRP10μg/kg;D组于术前24h及术前分别静脉注射相同体积的生理盐水;E组无预处理。用硝基四唑氮篮(TTC)染色判定梗死大小,并以坏死区占危险区的重量百分比表示;取血清测心肌酶学改变,用免疫组化方法检测心肌热休克蛋白70(HSP70)的表达。结果A组、B组、C组较D组、E组心梗面积明显缩小(P<0.01),心肌酶CK、LDH明显降低(P<0.01),A组心肌HSP70表达升高,C组心肌HSP70表达显著升高,B组、D组和E组心肌HSP70基本无表达,A组与B组、C组,D组与E组在心梗面积、心肌酶学的改变方面无明显差异(P>0.05)。结论CGRP预适应在整体大鼠能诱导早期及延迟性效应,缩小心梗面积,减少心肌酶漏出,对大鼠心肌缺血/再灌注损伤起保护作用;CGRP预适应在第一窗口期与第二窗口期的心肌保护作用无明显叠加。