The barrelettes--architectonic vibrissal representations in the brainstem trigeminal complex of the mouse. I. Normal structural organization.

The organization of the brainstem trigeminal complex (BTC) of the mouse is described, with emphasis on the normal organization of the vibrissal representations. Thionin staining for Nissal substance was employed to reveal the cytoarchitecture. Cytochrome oxidase histochemistry was used to reveal the chemoarchitecture. Golgi impregnation methods, in combination with thionin staining, were used to examine the neuronal dendritic morphology within a defined cytoarchitectonic context. An in vitro horseradish peroxidase labelling method was used to study the distribution and morphology of primary trigeminal afferent terminals within the BTC. The BTC consists of four distinct subnuclei: principalis (nVp), oralis (nVo), interpolaris (nVi), and caudalis (nVc). The present study shows that these sub-nuclei can be distinguished from each other on the basis of several anatomical criteria, including the distribution and density of neuronal size classes, histochemical staining intensity, morphology and orientation of neuronal dendrites, and size and texture of primary afferent terminal arbors. Anatomical manifestation of vibrissal representations within the BTC can be described in nVp, nVi, and nVc, but not in nVo. Within the three subnuclei where they are found, anatomical vibrissal representations are composed to architectural subunits that form an overall pattern homeomorphic to the pattern of vibrissae on the face of the animal. Each sub-unit forms a cylindrical tube running in a rostrocaudal orientation within the BTC. These sub-units will be called barrelettes. Cytologically, each barrelette consists of cell-dense "sides," surrounding a practically cell-free "hollow." Individual sub-units are separated by narrow, cell-free "septa." Histochemically, each subunit is manifested as a discrete patch of positive-staining reaction products. Differential interference contrast optics shows that these patches correspond precisely to the barrelette hollows. Evidence is presented to show that the barrelettes are the functional units for the processing of vibrissal sensory information. Terminal arborizations of individual primary afferents seem to be confined to the hollow of single barrelettes. The majority of neurons that form the sides of a barrelette have bitufted dendritic arbors, which project predominantly into the barrelette hollow, although a minority of neurons, particularly in nVi and nVc, also extend part of their dendritic arbors into adjacent barrelette hollows. The barrelette hollows are thus the principal neuropil region in which primary afferents and their target neurons interact. Contacts are made mainly between en passant varicosities and terminal boutons on primary afferent collaterals and dendritic spines and shafts of second order neurons.(ABSTRACT TRUNCATED AT 400 WORDS)     

Mercury and selenium interaction: A review

This paper reviews studies on mercury and selenium interaction. It includes the effects of selenium on mercury toxicity on the organism, organ/tissue, and subcellular levels. The paper also touches on possible mechanisms for the "protective action" of selenium against mercury toxicity and deals briefly with the synergism between the two elements.     

Adrenergic stimulation of isolated rat gastric mucosal cells

Summary Adrenergic stimulation of the adenylate cyclase (AC)-cAMP-system and ¹⁴C-aminopyrine accumulation, an indirect measure of parietal cell H⁺-production, was studied in different preparations of gastric mucosal cells.The ₂-adrenoceptor agonist hexoprenaline activated AC of crude homogenates from the gastric corpus of mouse, rat, guinea-pig, hog, dog and man. In isolated rat gastric cells (20% parietal cells), treated by low power sonication, 10^–8 to 10^–3 mol/l adrenaline and hexoprenaline activated AC equally potently and efficaciously by maximally 170%. Isoprenaline proved to be less effective activating up to 80%. 5·10^–5 mol/l GMP-PNP augmented basal activity 8.5 times and reduced the maximal efficacy. Adrenaline and hexoprenaline activated AC by maximally 120%, isoprenaline by 40%. The potency of adrenaline was 4 times lower, that of hexoprenaline 2 and that of isoprenaline 4 times higher in the presence of GMP-PNP. Adrenergic stimulation was inhibited by the -adrenoceptor antagonist propranolol, the effect of -adrenoceptor-blockade by phenoxybenzamine was less pronounced. In fractions with 7–80% of parietal cells, prepared by isopycnic centrifugation with Percoll, adrenaline and hexoprenaline activated AC or hexoprenaline enhanced the cellular level of cAMP in parietal cell poor and rich fractions. The degree of activation in response to histamine correlated with the number of parietal cells. ¹⁴C-Aminopyrine uptake was increasingly stimulated through 10^–8 to 10^–5 mol/l hexoprenaline, maximally by doubling the basal accumulation. 10^–4 mol/l histamine was 8 times more effective. 3·10^–7 mol/l propranolol inhibited the effect of 10^–5 mol/l hexoprenaline by 80%.The data suggest the localization of -adrenoceptors (likely -adrenoceptor) on parietal and other nonidentified gastric cells. At the parietal cell, adrenaline and hexoprenaline initiate activation of AC and hexoprenaline leads to H⁺-production. The responses are small compared to the effect of histamine. Thus, -adrenoceptor agonists exert intrinsic activity in relation to H⁺-production. Their influence on stimulated secretion of isolated cells remains to be elucidated.     

Blockade of presynaptic α-receptors and of amine uptake in the rat brain by the antidepressant mianserine

Summary Mianserine (Org GB 94, Tolvon^®) is 1, 2, 3, 4, 10, 14b-hexahydro-2-methyl-dibenzo [c, f] pyrazino [1, 3-a] azepine hydrochloride, a new antidepressant drug. Its effect on noradrenaline release and its capacity to inhibit amine uptake were investigated. Mianserine increased the release of ³H-noradrenaline from field-stimulated cortical slices previously labelled with the tritiated transmitter. The assumption that this effect is due primarily to the blockade of the presynaptic noradrenergic -receptors is supported by the fact that mianserine failed to augment ³H-noradrenaline release further after blockade of the presynaptic -receptors by phentolamine. In the reciprocal experiment, phentolamine failed to augment ³H-noradrenaline release after exposure of the slices to mianserine. The hypothesis is further reinforced by the fact that mianserine antagonized the reduction of ³H-noradrenaline release by clonidine in the same manner as the -blocking drugs phentolamine and phenoxybenzamine. Mianserine inhibited noradrenaline uptake in vitro and in vivo (in the rat heart and midbrain-diencephalon synaptosomes from pretreated rats.) Only a marginal inhibition of serotonin uptake was observed.It therefore appears that mianserine increases the concentration of noradrenaline in the synaptic cleft by blocking the presynaptic -receptors and inhibiting uptake. Whether or not this increase has functional consequences at postsynaptic noradrenergic receptor sites is unknown. It is possible, however, that postsynaptic receptor blockade counteracts the increase in available noradrenaline.A part of these results was presented at the 16th Spring Meeting of the German Pharmacological Society, Mainz, March 4–7, 1975     

Chronic ophthalmoplegia with anti-GQ1b antibody

Anti-GQ1b antibodies are typically found in patients with the Miller Fisher syndrome, all of whom will have, by definition, acute ophthalmoplegia. The authors describe three patients with chronic ophthalmoplegia in the presence of persistently high titers of immunoglobulin G anti-GQ1b antibody detected in an ELISA, one of whom improved with immunotherapy. Anti-GQ1b antibodies may be associated with some cases of chronic ophthalmoplegia of unknown cause.     

Open study evaluating lamotrigine efficacy and safety in add-on treatment and consecutive monotherapy in adult patients with epilepsy resistant carbamazepine and valproate

Lamotrigine is a broad-spectrum antiepileptic drug which is thought to act in part via a use-dependent blockade of voltage-sensitive sodium channels to stabilise the neuronal membrane. This results in the inhibition of the excessive release of excitatory amino acids, such as glutamate, during epileptic activity. An open, multicentre, prospective trial of lamotrigine was carried out in adult patients with drug-resistant epilepsy on monotherapy with carbamazepine or valproate. The primary aim of the study was to assess add-on lamotrigine withdrawing to monotherapy. 28-week clinical trial was divided into 4 phases: (1) Dose escalation period (4 weeks), (2) Add-on period (8 weeks), (3) Standard AED withdrawal period (8 weeks), (4) Lamotrigine monotherapy (8 weeks). Thirty-three patients were previously treated with valproate, 44 with carbamazepine. Of 77 patients recruited into the study, 64 patients (83%) completed add-on therapy, 49 patients (64%) completed lamotrigine monotherapy. 44% of all patients during the add-on phase and 48% during lamotrigine monotherapy had a reduction in seizure frequency of at least 50% compared with pre-study period. 13% of all patients achieved seizure freedom during add-on therapy and 18% during monotherapy. Improvement of Visual Analogue Scale (VAS) scores was observed in 65% and 57% patients respectively. A significant proportion of patients could be successfully converted to lamotrigine monotherapy. Lamotrigine was also generally well tolerated. 23 patients (30%) had at least one adverse event (AE), but only 1/4 of all AEs might be reasonably regarded as an effect of the medication. 7 patients (9%) discontinued prematurely from the study due to adverse event. More AEs were observed in add-on therapy than in lamotrigine monotherapy. The safety profile was consistent with that seen during other clinical trials with lamotrigine. CONCLUSIONS: 1. Lamotrigine is effective AED in add-on and monotherapy (responders rate--44% and 48% respectively). 2. In most cases conversion from add-on therapy to monotherapy can be done successfully. 3. Lamotrigine is a safe and well-tolerated drug.     

Comparative study of quality of life between the Chinese and Japanese adolescent populations

Researchers from Japan, China and Singapore have initiated a collaborative project, with the aim of comparing adolescent quality of life (QOL) internationally. This study presents the primary results of the investigation conducted in Beijing, China, and Kobe, Japan. The 70-item Quality of Life Questionnaire for Adolescents (QOLQA) was developed and evaluated in Japan and China. In total, 1114 Japanese and 613 Chinese junior high school students, aged 12-15 years, completed the questionnaire. Chinese students scored significantly higher than the Japanese students in overall QOL scores and in most domains. For both groups, subjects had highest score in the independence domain and lowest in psychological domain. In terms of overall QOL score, Chinese male students ranked first, followed by Chinese girls, Japanese boys, and Japanese girls. In the Japanese group, a continuing decrease of QOL scores with age was observed without exception, but no such tendency was present in their Chinese counterparts. No parallel relationship was observed between the higher level of economic development and better quality of life. The results also suggest that mental health promotion should be a priority in improving overall quality of life of adolescents both in Japan and China.     

高效液相色谱法同时测定复方对乙酰氨基酚维生素C泡腾片中2组分含量

目的 :建立同时测定复方对乙酰氨基酚维生素C泡腾片中对乙酰氨基酚和维生素C含量的高效液相色谱法。方法 :色谱柱 :YWG -C18柱 (10 μm,2 5 0mm× 4 .6mm) ;流动相 :甲醇 乙腈 0 .0 5mol·L-1磷酸二氢铵 磷酸缓冲液 (5 0∶11∶2 5 0 ) ;流速 :1.0mL·min-1;检测波长 :2 5 4nm。结果 :对乙酰氨基酚线性范围为 8～ 16 0mg·L-1;维生素C线性范围为 5～ 10 0mg·L-1。对乙酰氨基酚回收率为 10 0 .4 % (RSD =2 .4 0 % ) ,维生素C回收率为 10 1.2 % (RSD =1.90 % )。结论 :应用本法同时测定对乙酰氨基酚和维生素C含量 ,具有简便、快速、准确、可靠的特点     

老年急性脑梗死患者血浆内皮素、心钠素的动态变化及其临床意义

目的:测定老年急性脑梗死患者血浆内皮素(ET)及心钠素(ANP)含量的动态变化,并探讨ET,ANP在老年急性脑梗死过程中的作用。方法:用放射免疫测定(RIA)法测定老年急性脑梗死组109例,冠心病组87例和对照组(健康志愿者)60例的血浆ET,ANP水平。结果:老年急性脑梗死患者发病后d2,15,30的血浆ET,ANP含量分别(141.3±10.7),(142.7±18.2);(123.6±4.3),(118.6±12.1);(85.4±15.7),(101.9±9.3)pg·mL~(-1),老年冠心病患者和对照组入组初血浆ET,ANP含量分别为(85.7±10.2),(103.9±9.3);(45.7±12.2),(67.4±9.5)pg·mL~(-1)。老年急性脑梗死患者和老年冠心病患者血浆ET,ANP水平较对照组明显升高(P<0.05),且随时间延长,老年急性脑梗死患者血浆ET,ANP含量均逐渐降低。结论:ET,ANP与老年急性脑梗死的发生、发展密切相关。     

比色法测定消癌平注射液中总酚酸的含量

目的　建立消癌平注射液中总酚酸的含量测定方法。方法　以绿原酸为对照品 ,比色法测定。结果　绿原酸回归方程为A =35 8.1 4×C - 5 .3879(r=0 .9993,n =9)。在 2 0 .5～ 32 8μg范围内呈线性关系 ,平均回收率为 1 0 0 .4 8% ,RSD =1 .70 %。结论　所用方法简便、准确、快速 ,可作为该制剂的定量方法