不同碘营养水平对子代大鼠小脑神经细胞形态的影响

【目的】研究不同碘营养水平对子代大鼠小脑神经细胞形态发育的影响。【方法】应用MIAS-2000型图像分析系统对子代大鼠小脑各层的神经细胞进行形态学测量。【结果】低碘组（LI）14d龄外颗粒层（EGL）厚度明显大于正常碘组（NI）,14d和28d龄分子层厚度、Purkinje细胞截面积、颗粒细胞密度均明显小于NI组,且有统计学差异;各高碘组（HI）与NI组比较,随碘摄入量的增多,14d和28d龄分子层厚度、Purkinje细胞截面积、颗粒细胞密度有降低的趋势,尤其是50倍和100倍高碘组（50HI和100HI）颗粒细胞密度明显小于NI组,且有统计学差异。【结论】低碘和严重高碘可以影响小脑EGL细胞向分子层和内颗粒层神经细胞分化和迁移,同时影响了Purkinje细胞和颗粒细胞的正常发育;但轻度高碘组未见明显变化,提示：大鼠对高碘的耐受性要强于低碘。     

Effects of genetic factors and infection status on wing morphology of Triatoma dimidiata species complex in the Yucatán peninsula, Mexico

Triatoma dimidiata is one of the main vectors of Chagas disease, and it has been shown to be a species complex. In the Yucatán peninsula, Mexico, vector populations are non-domiciliated, and the transmission of Trypanosoma cruzi thus critically relies on vector dispersal. This leads us to study the morphologic variations in T. dimidiata wings with respect to genetic factors (sex and genotype at the ITS-2 locus), geographic location, and T. cruzi-infection status. Females were found to have larger and more symmetrical wings than males. Wing shape was influenced by ITS-2 genotypes, although differences are unlikely sufficient to allow taxonomic discrimination of the sibling species. Hybrids were shown to have similar fluctuating asymmetries in wing size and shape as parental species, but the level of asymmetry in shape varied slightly between villages. The two later findings are consistent with a high level of gene flow between parental species, and the high dispersal potential of these non-domiciliated vectors. More surprisingly, individuals infected with T. cruzi were found to have larger wings than non-infected ones. This effect, which was consistently observed across sexes, genotypes and villages, is likely to be due to a direct impact of T. cruzi on insect development. Sex and infection status are thus likely to be key factors influencing vector dispersal with important impacts on disease transmission, since dispersal directly controls the domestic abundance of these vectors. These aspects should be investigated further to fully capture the ecology and evolution of Chagas disease transmission by non-domiciliated vectors.     

A correlation of the surgical anatomy of the dura to head and neck surgery

Summary Head and neck surgery may be complicated by penetration of the dura resulting in meningitis, cerebrospinal rhinorrhoea, cerebral abscess or other intracranial complications. The strength of the dura mater both protects the brain and spinal cord and makes dura an ideal material for grafting (when needed). This study examines the thickness and histological composition of dura mater at various sites encountered in head and neck surgery. Dura was removed from eight specified locations in 14 adult cadavers. Microscopically, this dura was found to consist predominantly of collagen fibres, although the thickness of the dura varied between sites. Dura was significantly thinner in relation to the ethmoid sinus (P<0.01), tegmen (P<0.05) and sigmoid sinus (P<0.001), indicating its greater susceptibility to possible injury at these sites during surgery. The variety of its thickness also makes dura a more versatile homograft material than hitherto realised.Presented at the meeting of the British Association of Clinical Anatomists, Newcastle-upon-Tyne, England, 13 September 1985     

A morphometric study of the pallid mutant mouse inner ear

Mice homozygous for the mutant gene pallid (pa/pa) often lack otoconia in some or all of their maculae and are used to study the influences of gravity receptor hypostimulation on vestibular-related behaviors. Since the value of this animal model is based on the assumption that the vestibular sensorineural elements are normal, a morphometric analysis was done on the inner ear of these otoconia-deficient mice to see whether sensori-neural structures are also affected by the pallid gene. In pallid mice lacking all otoconia, the sensory epithelia of the utricle, saccule, and semicircular canal cristae were the same size as in their heterozygous (pa/+) controls. Although the superior and inferior divisions of the vestibular ganglion of the pallid mice were smaller than normal, the first-order neurons within these divisions were normal in size, number, and density. However, the superior divisions in both groups had larger neurons than did the inferior divisions. Within the pallid cochlea, first-order auditory neurons within the spiral ganglion were smaller than normal, but the scala media was larger. Since the significant vestibular influences of the pallid gene are limited primarily to the otoconia, behavioral abnormalities reported for these otoconia-deficient mice are apparently due only to gravity receptor hypostimulation.     

Survey of 21 inbred mouse strains in two laboratories reveals that BTBR T/+ tf/tf has severely reduced hippocampal commissure and absent corpus callosum

A morphometric survey of brain size and forebrain commissures of 21 inbred mouse strains from the Jackson Laboratory was done with animals tested in two laboratories as part of the Mouse Phenome Project. Strain BTBR T/+ tf/tf was found to have 100% total absence of the corpus callosum as well as severe reduction of the hippocampal commissure in almost every animal, the most severe commissure defect observed to date in any commercially available mouse strain. The strain 129S1/SvImJ had a milder defect with incomplete penetrance. Crosses of BTBR mice with inbred strains BALB/cWah1, 129P1/ReJ, and the recombinant strain 9XCA/Wah having a severe commissure defect supported a two-locus model of the genetic defect in these strains. Brain size varied greatly among strains but for any one strain was almost identical in mice housed for 5 weeks in the two laboratories. Sex differences in brain weight and forebrain commissure sizes were not statistically significant.     

Study of the rostral midbrain atrophy in progressive supranuclear palsy

Rostral midbrain atrophy in progressive supranuclear palsy (PSP) is detected by mid-sagittal plain magnetic resonance imaging (MRI). The shape of the atrophy looks like the bill of a hummingbird (hummingbird sign). We studied this sign to elucidate the nature of midbrain atrophy in PSP. Eight patients with PSP, 12 with Parkinson's disease (PD), and 10 normal controls were studied. Using mid-sagittal plain MRI, we measured the rostral and caudal midbrain tegmentum (MT), superior and inferior colliculus, pontine base, and tegmentum. We compared the length of the interpeduncular fossa, which is posterior to the mammillary body, to the diameter of the midbrain tegmentum. The multiple comparison method was used for the statistical analysis. The hummingbird sign was demonstrated in all of the PSP patients studied, and it was not observed in PD patients nor in normal controls. The hummingbird sign in the PSP patients was due to the atrophy of the midbrain tegmentum (rostral and caudal) and to a relative increase in the length of the interpeduncular fossa over that of the anteroposterior diameter of the midbrain tegmentum. The hummingbird sign, which represents the atrophy of the rostral midbrain tegmentum, strongly suggests the involvement of the rostral interstitial nucleus of the medial longitudinal fasciculus in patients with PSP. Demonstration of a hummingbird sign on MRI is thought to be useful for a diagnosis of PSP.     

Morphological effects of neuropathy-inducing organophosphorus compounds in primary dorsal root ganglia cell cultures

Chick embryo dorsal root ganglia (DRG) cultures were used to explore early pathological events associated with exposure to neuropathy-inducing organophosphorus (OP) compounds. This approach used an in vitro neuronal system from the species that provides the animal model for OP-induced delayed neuropathy (OPIDN). DRG were obtained from 9-day-old chick embryos, and grown for 14 days in minimal essential medium (MEM) supplemented with bovine and human placental sera and growth factors. Cultures were then exposed to 1 microM of the OP compounds phenyl saligenin phosphate (PSP) or mipafox, which readily elicit OPIDN in hens, paraoxon, which does not cause OPIDN, or the DMSO vehicle. The medium containing these toxicants was removed after 12 h, and cultures maintained for 4-7 days post-exposure. Morphometric analysis of neurites was performed by inverted microscopy, which demonstrated that neurites of cells treated with mipafox or PSP but not with paraoxon had decreased length-to-diameter ratios at day 4 post-exposure. Ultrastructural alterations of neurons treated with PSP and mipafox included dissolution of microtubules and neurofilaments and degrading mitochondria. Paraoxon-treated and DMSO control neuronal cell cultures did not show such evident ultrastructural changes. This study demonstrates that chick DRG show pathological changes following exposure to neuropathy-inducing OP compounds.     

外源性雌激素对雌性青春期前大鼠性腺影响的形态计量学研究

目的 探讨外源性雌激素对青春期前大鼠子宫和卵巢影响的形态计量学变化。方法 40只6周龄雌性青春期前SD大鼠随机分为实验组（n=20）和对照组（n=20），分别肌肉注射苯甲酸雌二醇（40μg／kg）和等容积生理盐水2周，末次注射24h后用10％水舍氯醛麻醉，解剖取两组大鼠子宫、卵巢，比较器官湿重及其器官系数；做组织切片，在光学显微镜下观察并行随机采取图像输入Mivnt显微图像分析系统进行形态计量学分析，比较两组大鼠子宫内膜高度、肌层厚度以及卵泡总数、闭锁卵泡比例、卵泡总面积、卵泡总周长、卵泡面密度、卵泡周长密度。在SPSS13．0上进行两个独立样本t检验。结果 实验组大鼠子宫湿重、子宫系数、内膜高度及肌层厚度均明显高于对照组（P〈0.05）；实验组大鼠卵巢湿重、卵巢系数、卵泡总面积、卵泡总周长、卵泡面密度、卵泡周长密度均明显低于对照组（P〈0.05），卵泡总数、卵泡数密度两组比较差异无显著性（P〉0.05），但实验组大鼠闭锁卵泡／卵泡总数明显高于对照组。结论 外源性雌激素可明显损害青春期前大鼠子宫、卵巢的正常发育。     

新型中药复方制剂防治CoxB3感染小鼠急性实验性心肌炎的形态定量学研究

目的观察新型中药复方制剂心康口服液预防和治疗柯萨奇B3 (CVB3m)感染小鼠急性病毒性心肌炎形态学及形态定量学改变的作用.方法将小鼠随机等分为模型组、阳性药(干扰素、Ribavilin)对照组、心康口服液组及正常对照组,并腹腔接种CVB3m病毒液建立病毒性心肌炎模型.预防组在用药2d后建立病毒性心肌炎模型,连续用药20-22d,观察比较第5、10和20d小鼠心脏肉眼及组织形态学改变并进行形态定量学测量,所得数据用SPSS/PC软件包作统计学处理.结果心康口服液中、小剂量组及干扰素组第20d时心脏表面重度病变检出率与病毒组有显著意义P＜0.01;心肌组织重度损伤(心肌细胞大片坏死崩解)检出率第20d时均低于病毒感染对照组、Ribav-ilin对照组及干扰素对照组,其中,中、小剂量组与病毒组有显著意义P＜0.0l;心肌病变面积/全心面积比值第10d及20d时心康口服液中、小剂量组及干扰素对照组与病毒对照组有显著意义P＜0.01;平均病变面积预防用药第10d及20d,治疗用药第20d心康口服液中、小剂量组及干扰素组与病毒感染对照组有显著意义P＜0.0l.结论心康口服液对CVB3m病毒感染小鼠的预防性及治疗性给药可保护心肌,减轻心肌损伤及促进损伤心肌修复,其预防作用类似干扰素,治疗作用优于Ribavilin,预防用药疗效较治疗用药为好.     

Role of the gonads in sex differentiation of growth hormone-releasing hormone and somatostatin neurons in the mouse hypothalamus during postnatal development

We clarify the mechanism of sexual dimorphism of growth hormone releasing hormone (GHRH) neurons in the arcuate nucleus (ARC) and somatostatin (SS) neurons in periventricular nucleus (PeN), by studying the role of the gonads during the neonatal period and after puberty using immunohistochemical and morphometric methods. As in our previous works the numbers of ARC GHRH-ir and PeN SS-ir neurons were significantly greater in adult normal male (NM) mice than in adult normal female (NF) mice. Adult female mice that were ovariectomized neonatally (NOF) increased the expression of GHRH-ir neurons to the male pattern, but adult female mice ovariectomized after puberty (APO) did not change. Adult male mice castrated neonatally and after puberty (NCM and APC, respectively) were not significantly different from NM mice. However, NCT male mice, which were castrated neonatally and transplanted with ovary just before puberty, showed a significantly reduced number of GHRH-ir neurons compared with NCM mice, but no significant difference from NM and NF mice. On the other hand, the PeN SS-ir neuron expression in NCM mice and APC mice showed a significant reduction compared with NM mice, but no significant difference from NF mice. The number of PeN SS-ir neurons in NOF increased to match that of NM mice. Our results suggest that the presence of the ovary during postnatal life inhibits the development of ARC GHRH-ir neurons. The presence of the testis during postnatal life may stimulate the development of PeN SS-ir neurons, while the presence of the ovary during neonatal period may inhibit the development of PeN SS-ir neurons; the presence of ovary after puberty does not inhibit.