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PubMed1976

The olivocerebellar projection in the cat studied with the method of retrograde axonal transport of horseradish peroxidase. III. The projection to the vermal visual area.

Horseradish peroxidase (HRP) was injected separately in one of the cerebellar lobules VI, VIIA, VIIB, VIIIA or VIIIB (together corresponding to the vermal visual area) in 17 cats. After 1-3 days the distribution of labeled cells in the inferior olive was mapped. In spite of some overlapping it is clear that the various lobules of the vermal visual area receive fibers from separate parts of a horseshoeshaped region in the caudal half of the contralateral medial accessory olive (fig. 5C). The projection area of lobule VIIA is found caudomedially and overlapping with the area supplying lobule VIIB. This in addition receives a few fibers from the nucleus beta. Fibers terminating in lobule VIIIA arise caudolaterally as do fibers destined for lobule VIIIB. A central part of the total projection area projects to lobule VI. Following injections leading to a similar extent of cortical staining in lobules VI, VII or VIII the projection of labeled cells in the corresponding projection areas differ markedly. In the area of lobule VII apparently all cells are labeled, in the area of lobule VI the density of labeled cells is considerably less, and in that of lobule VIII there are rather few labeled cells. In a few cases with widespread staining of the cerebellar visual area there was spreading of HRP to the nucleus fastigii. The projection to this form the olive was therefore investigated to avoid erroneous conclusions. In the discussion it is pointed out that on most points our findings agree fairly well with the results of studies of the olivocerebellar projection undertaken with other methods (studies of retrograde cellular changes, electrophysiological methods). No support for a longitudinal subdivision of lobules VI-VIII was found. Studies of the available literature indicate that the areas in the medial accessory olive projecting onto lobules VI-VIII probably do not receive direct afferents from regions which are known to be concerned in the transmission of visually evoked impulses. Fibers to the olive from the superior colliculus appear to pass to the nucleus beta only. This projects mainly to the uvula, to a little extent only to lobule VII. However, it may be imagined that visual impulses may reach the vermal visual area via the inferior olive by way of intercalated neurons, for example in the mesencephalic RF. Major contingents of afferents to the olivary regions projecting onto the vermal area come from the spinal cord, the motor cortex and the periaqueductal gray.

Animals↗
PubMed1986

Origin of mammalian thalamocortical projections. I. Telencephalic projections of the medial geniculate body in the opossum (Didelphis virginiana).

Telencephalic projections from the medial geniculate nucleus (MG) in opossum were traced with tritiated leucine autoradiography and by horseradish peroxidase and fluorescent dye retrograde labeling techniques. The results show that the opossum's MG contains two separate populations of neurons-one in the anterior two-thirds of MG projecting to auditory neocortex, the other occupying the entire caudal one-third of MG and projecting mostly to lateral amygdala and putamen. Because the subcortical projection of the MG in opossum is larger than that seen in any other mammal to date, it is reminiscent of the subcortical projections of the MG in reptiles and birds. Furthermore, when the subcortical projections of the MG in reptiles and opossums are compared with similar subcortical projections of the MG in rats, cats, and monkeys, the proportion of the MG neurons projecting to subcortical structures is seen to be inversely related to the recency of each animal's common ancestry with primates. The possibility that the subcortical projection of the MG in mammals is homologous with that seen in reptiles or birds implies that it might be a dwindling vestige of the projection present in the common ancestry of reptiles and mammals.

Animals↗
PubMed1994

Projections from the presubiculum and the parasubiculum to morphologically characterized entorhinal-hippocampal projection neurons in the rat.

The relations between the inputs from the presubiculum and the parasubiculum and the cells in the entorhinal cortex that give rise to the perforant pathway have been studied in the rat at the light microscopical level. Projections from the presubiculum and the parasubiculum were labeled anterogradely, and, in the same animal, cells in the entorhinal cortex that project to the hippocampal formation were labeled by retrograde tracing and subsequent intracellular filling with Lucifer Yellow. The distribution and the number of appositions between the afferent fibers and hippocampal-projection neurons in the various layers of the entorhinal cortex were analyzed. The results show that layers I-IV of the entorhinal cortex contain neurons that give rise to projections to the hippocampal formation. The morphology of these projection neurons is highly variable and afferents from the presubiculum and the parasubiculum do not show a preference for any specific morphological cell type. Both inputs preferentially innervate the dendrites of their target cells. However, presubicular and parasubicular projections differ with respect to the layer of entorhinal cortex they project to. The number of appositions of presubicular afferents with cells that have their cell bodies in layer III of the entorhinal cortex is 2-3 times higher than with cells in layer II. In contrast, afferents from the parasubiculum form at least 2-3 times as many synapses on the dendrites of cells located in layer II than on neurons that have their cell bodies in layer III. Cells in layers I and IV of the entorhinal cortex receive weak inputs from the presubiculum and parasubiculum. Not only is the presubiculum different from the parasubiculum with respect to the distribution of projections to the entorhinal cortex, they also differ in their afferent and efferent connections. In turn, cells in layer II of the entorhinal cortex differ in their electrophysiological characteristics from those in layer III. Moreover, layer II neurons give rise to the projections to the dentate gyrus and field CA3/CA2 of the hippocampus proper, and cells in layer III project to field CA1 and the subiculum. Therefore, we propose that the interactions of the entorhinal-hippocampal network with the presubiculum are different from those with the parasubiculum.

Animals↗
PubMed1988

Distribution of cells projecting to thalamus vs. those projecting to cerebellum in subdivisions of the dorsal column nuclei in raccoons.

To learn the distribution of cells projecting to the thalamus, as opposed to the cerebellum, in the mechanosensory nuclei of the dorsal medulla of raccoons, we analyzed the retrograde transport of horseradish peroxidase from the ventrobasal complex of the thalamus and from the cerebellum. We found six nuclear regions projecting heavily to the thalamus with very small projections to the cerebellum: Bischoff's, central cuneate, central gracile, rostral cuneate, rostral gracile nuclei, and cell group z. Two regions showed heavy projections to the cerebellum with no projections to the thalamus: the lateral portion of the external cuneate nucleus and the compact portion of cell group x. Four regions showed more equivalent projections to both target regions: basal cuneate, medial portion of the external cuneate nucleus, medial tongue extension of the external cuneate nucleus, and reticular portion of cell group x. Three more ventral regions were labeled: lateral cervical nucleus from thalamic injections but not from cerebellar injections; central cervical nucleus from cerebellar injections, which crossed the midline, but not from thalamic injections; and lateral reticular nucleus from both target regions. In most medullary regions, most cells project to one target and very few project to the other; we suggest that the cells projecting to the minor target convey samples of the information going to the major target.

Animals↗
PubMed1999

Characterization of the extent of pontomesencephalic cholinergic neurons' projections to the thalamus: comparison with projections to midbrain dopaminergic groups.

We sought to determine whether pontomesencephalic cholinergic neurons which we have been shown previously to project to the substantia nigra and ventral tegmental area also contribute to the thalamic activation projection from the pedunculopontine and laterodorsal tegmental nuclei. Retrograde tracing, immunohistochemical localization of choline acetyltransferase and statistical methods were used to determine the full extent of the cholinergic projection from the pedunculopontine and laterodorsal tegmental nuclei to the thalamus. Progressively larger Fluoro-Gold injections in to the thalamus proportionally labeled increasing numbers of pontomesencephalic cholinergic cells both ipsi- and contralaterally in the pedunculopontine and laterodorsal tegmental nuclei. Multiple large thalamic injections left only a small fraction of the ipsilateral pontomesencephalic cholinergic group unlabeled. This small remainder did not correspond to the populations which project to the substantia nigra and ventral tegmental area, thereby indicating that substantia nigra- and ventral tegmental area-projecting cholinergic neurons must also project to the thalamus. We examined whether there existed any set of cholinergic neurons in the pedunculopontine and laterodorsal tegmental nuclei which did not innervate a thalamic target. The distribution of descending projections of the pedunculopontine and laterodorsal tegmental nuclei demonstrated that the unlabeled remainder cannot correspond to a purely descending group. We also show that substance P-positive cholinergic cells in the laterodorsal tegmental nucleus project to the thalamus. Further studies demonstrated that the small population of cholinergic cells left unlabeled from the thalamus were the smallest sized cholinergic cells, and included two groups of small, light-staining cholinergic cells located in the parabrachial area and central gray, adjacent to the main pedunculopontine and laterodorsal tegmental nuclei cholinergic groups. These small cells, in contrast to thalamic-projecting cholinergic cells, did not stain positively for reduced nicotinamide adenine dinucleotide phosphate-diaphorase. Taken together, these results indicated that all of the reduced nicotinamide adenine dinucleotide phosphate diaphorase-positive/choline acetyltransferase-positive neurons of the pedunculopontine/laterodorsal tegmental nuclei ascend to innervate some portion of the thalamus, in addition to the other targets they innervate. These findings indicate that the diverse physiological and behavioral effects attributed to the activity of pontomesencephalic cholinergic neurons should not be dissociated from their activating effects in the thalamus.

Animals↗
PubMed2004

Virtual reality for simulation of radiographic projections: validation of projection geometry.

OBJECTIVE: To develop a software for virtual reality (VR) simulation of X-ray images based on perspective projections through a patient model derived from data from a CT examination and to evaluate the accuracy in the projection geometry obtained by the software. METHODS: A VR software was developed on a personal computer, with models of a patient, an X-ray machine and a detector. The model of the patient was derived from data from a CT examination of a dry skull. Simulated radiographic images of the patient model could be rendered as perspective projections based on the relative positions between the models. The projection geometry of the software was validated by developing an artificial CT data set containing high attenuation points as objects to be imaged. The accuracy in projection geometry was evaluated in a systematic way. The distances between two dots, representing the projected test points in the simulated radiographic images, were measured. They were compared with theoretical calculations of the corresponding distances using traditional mathematical tools. RESULTS: The difference between the simulated and calculated projected distances never exceeded 0.5 mm. The error in simulated projected distances was in most cases within 1%. No systematic errors were revealed. CONCLUSION: The software, developed for personal computers, can produce simulated X-ray images with high geometric accuracy based on perspective projections through a CT data set. The software can be used for simulation of radiographic examinations.

Computer Simulation↗
PubMed1983

[Experimental anatomic study of the topography of the retinofugal projections in Discoglossus pictus (Amphibia, Anura). II. The tectum: existence of a double-system of primary optic projections].

The possibility of retinotopic organization of bilateral retinotectal projection was studied by fotal retinal lesions followed by the Fink-Heimer technique. This work in Discoglossus pictus (Amphibia, Anura) shows two types of direct visual projections: a contralateral projection within the tectal layer 9 and a bilateral projection on tectal layer F of Potter (1969). The ipsilateral projection within tectal layer 9, earlier described after enucleation (Picouet et Clairambault, 1977), is not observed here. We discuss about reasons we failed to reveal it. Although appearing to be grossly in accord with data of literature, the retinotopic pattern of "classical" retinotectal projection (on layer 9) of Discoglossus presents some differences as the overlap of quadratic retinal projections. The anatomical tectal retinotopy appears less precise that physiologic retinotopy. The bilateral projections on layer F are characterised by medial (and specially medioposterior) location and the complete absence of retinotopy. All lesions in different parts of retina lead degeneration which take place in a series of distinct loci in the dorsal layer F. We discuss about a possible participation of axial optic tract to this projection.

Animals↗
PubMed1987

Projection and projective identification: developmental and clinical aspects.

Projective identification and projection are defined, described, and contrasted. Projective identification is seen as an early or primitive defensive operation, and projection as later or more advanced and derivative in nature. The developmental origins and adaptive functions of projective identification are examined with an emphasis on the cognitive preconditions for the operation of this defense. The varying functions of both defensive operations are described within the context of psychotic, borderline, and neurotic personality organization. Case material is presented to illustrate the diagnostic approach to and the clinical functions of projective identification, particularly its importance in contributing to complementary identification in the countertransference. Also illustrated is the technical management of severe transference regression under the impact of projective identification. Finally, alternative approaches to the diagnosis and interpretation of projective identification are discussed.

Adult↗
PubMedDate not supplied

The contoured auricular projection graft for nasal tip projection.

In all rhinoplasty surgery, the universal need exists to increase, decrease, or preserve existing tip projection. When proper tip projection is lacking, a variety of techniques are useful for improving projection. We describe a valuable technique for tip projection, particularly useful and indicated in the Asian rhinoplasty, African American rhinoplasty, and in certain revision rhinoplasties. In the past 15 years, the senior author (M.E.T.) has used the contoured auricular projection graft in selected patients for achieving satisfactory tip projection in patients with blunted tips. The aesthetic outcomes have been predictable, pleasing, and reliable for the long term. Precision pocket preparation for auricular conchal cartilage graft placement is key to symmetry and projection of the final outcome. The results yielded a rounded nasal tip that may be more natural-appearing in Asians, African Americans, and selected patients with revision rhinoplasty. The contoured auricular projection graft provides a highly useful graft for the nasal tip.

Asian People↗
PubMed1977

The olivocerebellar projection in the cat studied with the method of retrograde axonal transport of horseradish peroxidase. IV. The projection to the anterior lobe.

Following injections of horseradish peroxidase (HRP) in the cerebellar cortex of the anterior lobe of the cat, the distribution of labeled cells in the inferior olive was mapped. The findings largely confirm those made previously in studies of olivary retrograde cell loss following cerebellar ablations (Brodal, '40b). In addition, they reveal further olivary areas projecting onto the anterior lobe, and permit a more detailed analysis of the pattern in this projection. Concerning major points the results are in agreement with physiological studies by Armstrong et al. ('74). They bring supporting evidence for a longitudinal zonal pattern in the anterior lobe (fig. 6C). The middle zone of the vermis receives its fibers from a large central area in the caudal half of the medial accessory olive, a lateral zone of the vermis from the lateral half of the dorsal accessory olive. Both olivary areas project to the corresponding cerebellar zone throughout lobules V-I. The lateralmost part of the anterior lobe (lobules IV-V) receives afferents from an area in the dorsal lamella of the principal olive. The intermediate part of lobules IV-V receives afferents from the medial half of the dorsal accessory olive and from an area in the rostral half of the medial accessory olive. There is suggestive evidence that the latter projects to a middle zone, the former to a medial and a lateral zone within the intermediate part as found physiologically. Conclusions concerning projections to the intermediate part of lobules III-II could not be made. The findings in this and preceding studies with the HRP-method show that the concept of a longitudinal pattern in the cerebellum is scarcely generally valid of the entire olivocerebellar projection. Within the projections of the lateral half of the dorsal accessory olive and the area in the rostral part of the medial accessory olive there appears to be a topical relation with the folial pattern in the anterior lobe. An analysis of the findings with reference to the afferents traced anatomically to the various olivary areas permits some conclusions as to the functional role of the olivary areas. Comparison with Oscarsson's ('73) diagram of the sites of termination of two of the spinal-olivary pathways (his DF-SOCP) and VF-SOCP) permits an anatomical explanation as concerns the projections to the vermis, while correlations as concerns the intermediate part are less satisfactory.

Animals↗
PubMed1982

Mesostriatal projections from ventral tegmentum and dorsal raphe: cells project ipsilaterally or contralaterally but not bilaterally.

The cells of origin of the brainstem projection to the caudate-putamen (CP) were examined in the albino rat by the use of two fluorescent retrograde tracers. Nuclear yellow was injected into the CP of one hemisphere and granular blue was injected into the contralateral CP. Retrogradely labeled cells were studied in the substantia nigra (SN), ventral tegmental area (VTA) and dorsal raphe (DR). The results confirm previous findings indicating the existence of contralateral projections from SN and VTA to the CP. Cells on both sides of the midline of the DR also project to either CP. Contralaterally projecting SN/VTA cells were located in areas of these nuclei which corresponded to the center of the ipsilaterally projecting cell region; the exact locations depended on the placement of the injection in the CP. In DR, contralaterally projecting cells were most often observed near the midline, although labeled cells were occasionally observed in the lateral wings of the DR. Cells labeled by contralateral injections were interdigitated with, but not identical to, cells labelled by ipsilateral injections. That is, contralaterally projecting cells and ipsilaterally projecting cells constituted separate populations within the SN, VTA and DR.

Animals↗
PubMed2005

Vocal projection in actors: the long-term average spectral features that distinguish comfortable acting voice from voicing with maximal projection in male actors.

This study explored whether acoustic and perceptual features could distinguish comfortable from maximally projected acting voice. Thirteen professional male actors performed a passage from William Shakespeare's Julius Caesar twice. The first delivery used their comfortably projected voices, whereas the second used maximal projection. Acoustic measures, expert ratings, and self-ratings of projection and voice quality were investigated. Long-term average spectra (LTAS) and sound pressure level (SPL) analyses were conducted. Perceptual variables included projection, breathiness, roughness, and strain. When comparing the intensity difference between the higher (2-4 kHz) and lower (0-2 kHz) regions of the spectrum in voice samples from the maximal projected condition, LTAS analyses demonstrated increased acoustic energy in the higher part of the spectrum. This LTAS pattern was not as evident in the comfortable projected condition. These findings offered some preliminary support for the existence of an actor's formant (prominent peak in the upper part of the spectrum) during maximal projection.

Adult↗
PubMed2006

A general exact method for synthesizing parallel-beam projections from cone-beam projections via filtered backprojection.

In recent years, image reconstruction methods for cone-beam computed tomography (CT) have been extensively studied. However, few of these studies discussed computing parallel-beam projections from cone-beam projections. In this paper, we focus on the exact synthesis of complete or incomplete parallel-beam projections from cone-beam projections. First, an extended central slice theorem is described to establish a relationship between the Radon space and the Fourier space. Then, data sufficiency conditions are proposed for computing parallel-beam projection data from cone-beam data. Using these results, a general filtered backprojection algorithm is formulated that can exactly synthesize parallel-beam projection data from cone-beam projection data. As an example, we prove that parallel-beam projections can be exactly synthesized in an angular range in the case of circular cone-beam scanning. Interestingly, this angular range is larger than that derived in the Feldkamp reconstruction framework. Numerical experiments are performed in the circular scanning case to verify our method.

Algorithms↗
PubMed2001

Managing externally financed projects: the Integrated Primary Health Care Project in Bolivia.

Bolivia is one of the poorest countries in Latin America. Health indicators are very poor, communicable diseases are prevalent and, coupled with malnutrition, remain the major killers of children under 5 years old. The Integrated Primary Health Care Project (PROISS) was a US$39 million project executed by the Ministry of Health (MOH), 50% financed by the World Bank and aimed at improving primary health care in the four largest Bolivian municipalities. The implementation of the project started in 1990 and ended in 1997. During implementation it went through three distinct phases: Phase 1 (1990-94) was a period characterized by conflict and confusion; Phase 2 (1995-mid-1996) documented major improvements in coverage and service quality; and Phase 3 (mid-1996-97) witnessed the decline of the project. This paper explores the factors that contributed to the success and the decline of the project, draws lessons for project managers and international agencies involved in the definition and implementation of social sector projects, and discusses the unlikelihood that externally financed projects can have a sustainable impact on the development of the health sector of recipient countries.

Bolivia↗
PubMed2004

Projecting the demographic consequences of adult HIV prevalence trends: the Spectrum Projection Package.

This paper describes the software package Spectrum, which is a modular program that is used to examine the consequences of current trends and future program interventions in reproductive health. It is used to determine the consequences of the HIV/AIDS epidemic, including the number of people living with HIV/AIDS by age and sex, the number of AIDS deaths, and the number of orphans as a result of AIDS, as well as other demographic indicators of interest, such as life expectancy and <5 mortality. The core of Spectrum is a demographic projection model called DemProj, which projects the population by age and sex. Other modules interact with the demographic projection. The HIV/AIDS projections are added to the demographic projections using a module called AIDS Impact Model. This module uses the projection of adult HIV prevalence over time, which is prepared using the Estimation and Projection Package model or the projection workbook. It also requires assumptions about the epidemiology of HIV, including the ratio of female:male prevalence, the distribution of infection by age, the distribution of the time from infection until AIDS death, and the effect of HIV on fertility.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Development of an evaluation criteria for rural water supply and environmental sanitation programme in project and non-project villages--a case study.

The Rural Water Supply and Sanitation (RWSS) in project and non-project villages of Mysore Taluk has been evaluated and discussed in this paper. The study area covered two villages (Yelwala and Kadakola) where Integrated Water Supply Scheme (IRWSS) was implemented under World Bank Project and two non-project villages (Belwadi and Byathahalli) closer to them. Pre and post scenarios of the project and non-project villages were investigated in terms of water quality analysis and also grading of villages has been done on the basis of water supply, sanitation, hygienic awareness and practices. Matrix methodology was used to evaluate the indicators from the survey data gathered from all studied villages. Finally, the villages were graded on the basis of cumulative value obtained for each village. Water quality analysis depicted turbidity, total dissolved solids and hardness being high and iron deficiency was also observed in water samples of all the villages. It was concluded that the present method of evaluation of rural water supply and sanitation project could be effectively applied to different upcoming projects.

Community Participation↗
PubMed1999

[Quality of life and well-being in a housing project in Berlin--experiences gained in cooperation between a community health promotion office and a university-based public health project].

The realization of a community-based health promotion within the framework of a cooperation between a public health office and a university-based PH project is described and discussed. First of all, the project, the cooperating partners and the common aims are described. We will then deal with telephone survey as the method used, and present the results. In a third step the methods and results of the "future workshops" are discussed. Finally there is a critical reflection on the course of the project, the limiting factors of the actions and consideration of further developments. The project dealt with was a cooperation of a community public health agency (Plan- und Leitstelle) in the district of Berlin-Wilmersdorf and the research project A8 "Cooperative project development for communal health promotion" of the Berlin Centre for Public Health at the Technical University Berlin. Starting point was the agreement for those politically responsible of the district that the living quarter "Schlangenbader Strasse" was a focus of social problems. The quarter had been built in 1980 above a highway with 1800 apartments for 4000 people. Health promotion was defined as a concern of a wide range of sectors within the community. Mutual rights and responsibilities of the cooperating partners were laid down in a contract. The Plan- und Leitstelle tried to gain experience with the definition of health promotion the university partners stood for. This introduces a notion of health beyond bio-medical understanding and deals with the connection of quality of life, well-being and the environment in the residential area. Thus health- or sickness-related variables were not specifically asked for. One result is that actors within the given framework are reluctant to permit operationalisation of this concept. The telephone survey reached 324 household within 10 working days. 68p.c. of the interviewed were pleased with the comfort of the apartments, 37p.c. enjoyed the peace and quiet and 35p.c. the green around the housing project. Unpleasant were for 51p.c. the dirt, 33p.c. complained about vandalism, 30p.c. about the high rent, especially the extras. Safety improvements were asked for by 17p.c. Some 12p.c. were willing to become involved in bringing about those improvements. This willingness was confirmed by the good response to two future workshops with those living in the quarter.

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