Calcium-Binding Proteins and Cytochrome Oxidase Activity in the Pigeon Entopallium: A Comparative Analysis of Interspecies Variability as Related to the Discussion on Avian Entopallium Homology

We report the results of our studies of the distribution patterns of calcium-binding proteins (parvalbumin, PV, and calbindin, CB) and metabolic activity (cytochrome oxidase, CO) in the pigeon entopallium—the telencephalic projection field of the tectofugal visual system. These characteristics were comparatively analyzed in different avian species in the light of the recent revision of entopallial projections’ nomenclature (Krützfeldt and Wild, 2005). We demonstrate that in the pigeon neuropil both high PV immunoreactivity and CO activity as well as lower CB immunoreactivity are confined to the core region of the entopallium (E). The latter contains cells immunoreactive (ir) to PV and CB and having a heterogenous repertoire: small/medium-sized granular and large multipolar cells. They overlap in E and partly colocalize within the same cell, but differ in the internal (Ei) and external (Ex) portions by distribution density and labeling intensity. CO activity was identified in both cellular morphotypes. Sparse PV- and CB-ir cells were found in the perientopallium (Ep). The interspecies variability of PV and CB immunoreactivity, described in the avian entopallium by other authors, indicates its dependence on the adaptive functional specialization which underlies selective expression of these calcium-binding proteins. The above as well as the pertinent literature data are discussed in the wake of the current discussion on homology of the avian entopallium, supporting the idea of the existence in sauropsid amniotes of the ancestral precursor of the mammalian extrastriate visual cortex.     

Level of metabolic activity (cytochrome oxidase) as an index of functional significance of tectofugal and thalamofugal channels of the reptilian visual system

Using histochemical determination of activity of the mitochondrial oxidative enzyme cytochrome oxidase (CO) the metabolic activity in structures of brain of turtles and lizards was shown to be higher in centers of the tectofugal channel (tectal SGC, pretectal Ptv, thalamic Rot, telencephalic visual area of Advr of) than in the centers of the thalamofugal channel (thalamic GLd, Cxdl and Path of telencephalon) of the visual system. Some interspecies differences in distribution of CO activity in the tectal, thalamic, and telencephalic visual centers were revealed between terrestrial and pond turtles and lizards. The obtained data confirm the idea of the dominating role of the tectofugal visual pathway in information processing and organization of the usual behavior of reptiles.     

Study of GABA-immunoreactivity distribution in reptile amygdaloid complex

InEmys orbicularis turtles andOphisaurus apodus lizards GABA-immunoreactive (GABA-I) components (cell bodies and neuropiles) of all ventral and dorsal amygdaloid complex (AC) structures were examined as phylogenetically earlier or later using immunohistochemical methods. Maximum numbers of these structures are found in lateral regions of the ventral AC section, while the least are found in ventral, central, and medial portions. Furthermore, in lizards, a specialized laminar distribution of the GABA-I components is observed in n. sphaericus structures. In both turtles and lizards, against a background of immunopositive neuropile of moderate density, GABA-I neurons are detected in dorsal section structures. Results suggest that GABAergic innervation of the AC is subject to significant variation in conjunction with taxonomic, ecological, and other factors.I. M. Sechenov Institute of Evoutionary Physiology and Biochemistry, Russian Academy of Science, Saint Petersburg. Translated from Neirofiziologiya, Vol. 24, No. 1, pp. 68–77, January–February, 1992.     

Horseradish peroxidase study of connections of the hippocampal (mediodorsal) cortex ofOphisaurus apodus

Sources of afferent projections of the hippocampal (mediodorsal) cortex were detected in lizards (Ophisaurus apodus) by the retrograde horseradish peroxidase transport method. Labeled neurons after injection of the enzyme were most numerous in the anterior dorsolateral thalamic nucleus, mammillary body, superior nucleus raphe, dorsal cortex (ipsilaterally), and the hippocampal cortex of the contralateral hemisphere. Fewer neurons projecting into the hippocampal cortex were found in these same structures on the side opposite to that of the injection, and also in the ventromedial zone of the telencephalon (olfactory tubercle, the nucleus of Broca's diagonal band, and the nucleus accumbens), the preoptic region of the hypothalamus, and the ventrotegmental region of the midbrain. Endings of efferent fibers from the hippocampal cortex were found in the septum, thalamus, hypothalamus (mainly on the side of injection of the enzyme), and also in the hippocampal and dorsal cortex of both hemispheres. The results show that afferent and efferent connections of the lizard's hippocampal cortex are similar to those of mammals.     

Transthalamic conduction of visual impulses to the cortex and subcortical forebrain structures in turtles

The thalamic relays for the conduction of impulses arising during photic stimulation of the eyes and electrical stimulation of the tectum in the general cortex, hyperstriatum (the dorsal ventricular ridge), and the striatum proper were studied in the turtleEmys orbicularis. Acute experiments on immobilized animals showed that anodal polarization temporarily and destruction of n. rotundus irreversibly suppress the main negative wave of the responses to tectal stimulation and to flashes in the hyperstriatum, whereas the corresponding responses in the general cortex still persist. Polarization and destruction of the lateral thalamic region, including the lateral geniculate body, have the opposite effect: responses in the hyperstriatum to photic and tectal stimulation are virtually unchanged whereas those in the general cortex disappear, except their late components. Preceding single stimulation of the tectum or n. rotundus depresses responses in the hyperstriatum evoked by flashes. However, during stimulation of the lateral thalamic region, combined potentials and single unit responses appear in the hyperstriatum and interact with responses evoked by tectal stimulation. It is concluded that the main pathways in turtles which supply visual information to the general cortex and hyperstriatum differ: the former relay in the lateral thalamic region, the latter in n. rotundus, although some overlapping of their projections in the hyperstriatum and striatum is possible.I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Leningrad. Translated from Neirofiziologiya, Vol. 9, No. 5, pp. 486–494, September–October, 1977.     

Immunohistochemical analysis of the serotonin system in the brain of lizard Ophisaurus apodus

The distribution of serotoninergic neurons (localization of somata, principal fiber tracts and projection zones) was investigated in the brain of the lizard Ophisaurus apodus using a specific antibody directed against serotonin (5-HT). A comparison of the results with those of the literature revealed that in spite of minor variations in the distribution of 5-HT in the different reptiles examined there exist common features which correspond to a general organizational pattern.     

What helps and hinders midwives in engaging with pregnant women about stopping smoking? A cross-sectional survey of perceived implementation difficulties among midwives in the North East of England

ABSTRACT: BACKGROUND: Around 5,000 miscarriages and 300 perinatal deaths per year result from maternal smoking in the United Kingdom. In the northeast of England, 22% of women smoke at delivery compared to 14% nationally. Midwives have designated responsibilities to help pregnant women stop smoking. We aimed to assess perceived implementation difficulties regarding midwives' roles in smoking cessation in pregnancy. METHODS: A self-completed, anonymous survey was sent to all midwives in northeast England (n?=?1,358) that explores the theoretical explanations for implementation difficulties of four behaviours recommended in the National Institute for Health and Clinical Excellence (NICE) guidance: (a) asking a pregnant woman about her smoking behaviour, (b) referring to the stop-smoking service, (c) giving advice about smoking behaviour, and (d) using a carbon monoxide monitor. Questions covering Michie et al.'s theoretical domain framework (TDF), describing 11 domains of hypothesised behavioural determinants (i.e., 'knowledge', 'skills', 'social/professional role/identity', 'beliefs about capabilities', 'beliefs about consequences', 'motivation and goals', 'memory', 'attention and decision processes', 'environmental context and resources', 'social influences', 'emotion', and 'self-regulation/action planning'), were used to describe perceived implementation difficulties, predict self-reported implementation behaviours, and explore relationships with demographic and professional variables. RESULTS: The overall response rate was 43% (n?=?589). The number of questionnaires analysed was 364, following removal of the delivery-unit midwives, who are not directly involved in providing smoking-cessation services. Participants reported few implementation difficulties, high levels of motivation for all four behaviours and identified smoking-cessation work with their role. Midwives were less certain about the consequences of, and the environmental context and resources available for, engaging in this work relative to other TDF domains. All domains were highly correlated. A principal component analysis showed that a single factor ('propensity to act'), derived from all domains, explained 66% of variance in theoretical domain measures. The 'propensity to act' was predictive of the self-reported behaviour 'Refer all women who smoke……to NHS Stop Smoking Services' and mediated the relationship between demographic variables, such as midwives' main place of work, and behaviour. CONCLUSIONS: Our findings advance understanding of what facilitates and inhibits midwives' guideline implementation behaviours in relation to smoking cessation and will inform the development of current practice and new interventions. Using the TDF as a self-completion questionnaire is innovative, and this study supports previous research that the TDF is an appropriate tool to understand the behaviour of healthcare professionals.