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Biomedical subjects

C C Bell

Publications and source records attributed to C C Bell.

At least 91 records · Page 5Linked to original sources
PubMed1985

The mormyrid brainstem--II. The medullary electromotor relay nucleus: an ultrastructural horseradish peroxidase study.

The medullary relay nucleus of the mormyrid weakly electric fish Gnathonemus petersii is a stage in the command pathway for the electric organ discharge. It receives input from the presumed command or pacemaker nucleus and projects to the electromotoneurons in the spinal cord. Its fine structure and synaptology were investigated by electron microscopy. The origin of the terminals contacting the cell membrane of the neurons of this nucleus was determined by horseradish peroxidase (HRP) injections into different brain structures, namely into the bulbar command- and mesencephalic command-associated nuclei. Twenty-five to thirty large cells of about 45 micron in diameter constitute the medullary electromotor relay. Each cell has a kidney-shaped, lobulated nucleus, a large myelinated axon with a short initial segment and several long, richly arborizing primary dendrites. Many, if not all, cells are interconnected with large somatosomatic or dendrosomatic, dendrodendritic and dendroaxonic gap junctions. These junctions often occur in serial or triadic arrangements. The relay cells receive large club endings as well as small boutons. The club endings are found mainly on the soma and primary dendrites and are morphologically mixed synapses. The boutons are characterized by synapses which are only chemical and are distributed all over the cell membrane, but with a definitely higher frequency on secondary dendrites and more distal parts of dendritic processes. Horseradish peroxidase injections into the mesencephalic command-associated nucleus reveal a large number of labelled boutons on the secondary dendrites of the relay cells. Injections into the bulbar command-associated nucleus label the same type of boutons as mesencephalic injections, but also label club endings on relay cell soma and primary dendrites. The results support the conclusion made on the basis of previous light microscopical observations that boutons originate from the bulbar command-associated nucleus, whereas the club endings issue from the presumed pacemaker nucleus (nucleus c). The club endings of the bifurcating axons of this nucleus are labelled by retro- and anterograde transport of horseradish peroxidase; the bifurcating axons project simultaneously to the bulbar command-associated nucleus and the medullary relay nucleus.

Animals↗
PubMed1985

Prevalence of coma in black subjects.

Coma, commonly known as "being unconscious" or "out cold," is a state of consciousness characterized by a total inability to perceive incoming stimuli. A retrospective phenomenologic study found that 10 of 36 control, 19 of 36 precare, and 20 of 36 aftercare subjects (49 of 108, or 45.4 percent) had experienced coma at least once during their lives. The implications of these findings are discussed.

Black People↗
PubMed1985

Altered states of consciousness profile: an Afro-centric intrapsychic evaluation tool.

In an effort to develop an Afro-centric intrapsychic evaluation tool, the Community Mental Health Council, Inc., Altered States of Consciousness Research Team, developed a structured interview used to quantify and qualify the 17 states of consciousness(1) that occurred in black control, precare, and aftercare subjects. Differences were noted in the three groups as to the incidence, prevalence, and quality of the various states of consciousness. It was also noted that the profile obtained from the interviews yielded a sharp clinical picture of the subjects' total intrapsychic propensities.

Africa↗
PubMed1984

Prevalence of isolated sleep paralysis in black subjects.

Sleep paralysis is a state of consciousness experienced while waking from sleep or falling asleep. It is characterized by an experience of being unable to move for several seconds or minutes. This study represents the first survey to measure the incidence of this disorder in a black population of healthy subjects and psychiatric patients.

Adult↗
PubMed1983

Pathways of the electric organ discharge command and its corollary discharges in mormyrid fish.

The motoneurons which innervate the mormyrid electric organ are driven by a descending volley from the medullary relay nucleus. This nucleus does not initiate the electric organ discharge (EOD) but is driven in an obligatory manner by another center, a command nucleus. One goal of the present study was to identify this command nucleus anatomically. A second goal was to determine the pathways by which corollary discharges of the EOD motor command exert their effects on sensory input to the electroreceptive lateral line lobe. Horseradish peroxidase (HRP) was injected into the medullary relay nucleus and other EOD command-related centers. Placement was guided by recording the electrical activity preceding the EOD. A nucleus of smaller cells is found immediately beneath the large cells of the medullary relay nucleus. This nucleus, nucleus C, projects densely to the medullary relay nucleus and is hypothesized here to be the command nucleus. Nucleus C appears to receive input from the mesencephalon and from unspecified sources of input to the nearby reticular formation. Nucleus C projects to the medullary relay nucleus and to a lateral nucleus, the bulbar command-associated nucleus. This nucleus is probably the source of the corollary discharge signals. It projects to the medullary relay nucleus and to the paratrigeminal and mesencephalic command-associated nuclei. The latter two nuclei project to separate regions which in turn project to the electroreceptive lateral line lobe. There are thus at least two different paths by which the presumed EOD command nucleus, nucleus C, can affect the electroreceptive lateral line lobe.

Animals↗
PubMed1983

Survey of the demographic characteristics of patients requiring restraints in a psychiatric emergency service.

This paper examines the previously studied topic of the prevalence of uncontrollable behavior in psychiatric emergencies, using the need for restraints as an indicator, and seeks to discover demographic characteristics that were associated with patients needing restraints. The variables considered are sex, referral source, marital and financial status, race, education, diagnosis, age, and disposition. The findings of this survey were compared with those of another survey, which was conducted with a different population in a different community context, using tendency toward assault as an indicator of uncontrollable behavior. Although the two surveys were not strictly comparable, some interesting points were raised regarding differences and similarities.

Adolescent↗
PubMed1982

Black intrapsychic survival skills: alteration of states of consciousness.

Psychiatry tends to be interested only in states of consciousness as they relate to psychopathology. In this paper the author presents the thesis that the ability to alter one's state of consciousness is in fact a survival skill useful in coping with the physiologic and psychologic effects of stress. Furthermore, he discusses techniques indigenous to black culture for altering states of consciousness and gives phenomenologic black transcultural evidence that black culture is quite sophisticated in the area of intrapsychic survival skills.

Black People↗
PubMed1981

An efference copy which is modified by reafferent input.

In electric fish of the mormyrid family, an efference copy is present in the brain region that receives afferent input from ampullary electroreceptors. The efference copy is elicited by the motor command to fire the electric organ. Its effect is always opposite that the ampullary afferents responding to the electric organ discharge, and it changes to match variations in this afferent input. It probably reduces the central effects of activity in ampullary receptors evoked by the electric organ discharge.

Action Potentials↗
PubMed1981

Central distribution of octavolateral afferents and efferents in a teleost (Mormyridae).

The central distribution of afferents from individual eight nerve branches (N VIII) and mechanical lateral line end organs in mormyrid fish are described. Afferents were labeled with horseradish peroxidase (HRP) placed on the cut ends of the different N VIII branches and the anterior and posterior lateral line nerves. Descending, tangential, and magnocellular nuclei receive input almost exclusively from the utriculus and canals. Nucleus octavius receives afferents from the lateral line nerves and all N VIII branches, with one part receiving exclusive and bilateral input from the sacculus. Afferents from both lateral line nerves and all N VII branches, except the sacculus, end in eminentia granularis. Afferents from each of the two lateral line nerves and from each of three otolith branches of N VIII end in different regions of the anterior lateral line lobe, with some areas of overlap. Behavioral studies in other families of fish indicate that the utriculus and canals are critical for postural control, whereas the sacculus and possibly the lagena are concerned with hearing. Such findings, together with the results of this study, suggest that mormyrids and perhaps other fish possess separate auditory and vestibular centers within the octavolateral area. The HRP method also shows the cell bodies and axons of octavolateral efferents. N VIII and lateral line efferents arise from a common nucleus, and the central course of their axons parallels that of facial motoneurons. Axons of efferent cells divide to supply two or more branches of N VIII and some axons supply both lateral line and N VIII end organs.

Afferent Pathways↗
PubMed1981

Central connections of the posterior lateral line lobe in mormyrid fish.

Primary electroreceptor afferents terminate in the posterior lateral line lobe (PLLL) in electroreceptive teleosts. This paper examines the central connections of PLLL in fish of the family Mormyridae using horseradish peroxidase and tritiated amino acid tracing techniques. Some connections of the closely related lobus caudalis of the cerebellum are also examined. There are three zones on each side of the mormyrid PLLL cortex. Two receive input from mormyromast receptors, and one from ampullary receptors. An intrazonal projection system, intrinsic to PLLL, connects neighboring points within each zone. It also joins corresponding zones on the two sides of the body via commissural fibers. An interzonal system connects the two mormyromast zones on the same side of the midline. Central structures which project to PLLL include lobus caudalis, nucleus paratrigeminalis lateralis, and nucleus praeeminentialis. Nucleus praeeminentialis projects bilaterally and somatotopically to the lower molecular layer of PLLL. PLLL cortex projects bilaterally and somatotopically to two major mesencephalic sites: n. praeeminentialis, and n. lateralis. Somatotopically corresponding points in each zone of PLLL cortex project to the same small region of n. lateralis. Nucleus lateralis has a large and somatotopically organized projection to n. praeeminentialis. The afferent and efferent connections of lobus caudalis are similar to those of PLLL, indicating its close association with the electrosensory system. The anatomical results show that there is ample opportunity for electrosensory information arising on left and right sides of the body to interact centrally. One can suggest that comparison of afferent input from the two sides would reduce the non-significant variability which affects both of them equally. The results also show the presence of several somatotopically organized feedback lops which return the results of higher order processing of electrosensory information to earlier stages.

Afferent Pathways↗
PubMed1981

Electrosensory pathways to the valvula cerebelli in mormyrid fish.

The valvula cerebelli of mormyrid fish has been implicated in the electroreceptive capabilities of these animals. This study uses peroxidase and tritiated amino acid tracing techniques to examine the pathways by which electroreceptive information gains access to the valvula. Ampullary and mormyromast receptor information reaches the medial and ventrolateral portions of the valvula by means of a large, direct projection from n. lateralis, part of the midbrain electrosensory area. In addition, smaller indirect n. lateralis-valvular projections travel via a pretectal nucleus and the so-called postventral thalamic nucleus, Knollenorgan receptor information ends in the dorsolateral portion of the valvula. A small, relatively direct pathway runs via n. medialis ventralis, but most Knollenorgan information appears to travel via an indirect system involving n. extrolateralis pars posterior and n. isthmi. The lateral line processing areas of the valvula project back onto many of the midbrain electrosensory nuclei. These results indicate that much of the cerebellum of this family is devoted to sensory processing rather than motor functions.

Afferent Pathways↗
PubMed1981

Psychoneuroendocrinology, biorhythms, and Chinese medicine.

The discovery of an endogenously formed opioid substance in the body which is intimately related to corticotrophin and, thus, a major consideration in the body's response to stress already has demonstrated the impact that psychoneuroendocrinology can have on the practice of medicine. The psychoneuroendocrinologic system is characterized by a daily rhythm; because of this rhythmic variation, the body is in different physiologic states at different times of the day. This has raised some important questions for clinical practice. Western medical science and Chinese medicine are compared and suggestions are made on how to best utilize the knowledge currently being gained in psychoneuroendocrinology and biorhythms.

Adrenocorticotropic Hormone↗
PubMed1981

Misdiagnosis of black patients with manic depressive illness: second in a series.

In a previous article (J Natl Med Assoc 72(2): 141, 1980), the authors proposed that, despite several attempts to lay to rest the myth that blacks do not demonstrate similar prevalence rates of manic depressive illness when compared to whites, many black patients with manic depressive illness are frequently misdiagnosed. In a survey of the outpatient psychiatric clinic at Jackson Park Hospital, it was found that black patients in this clinic have similar prevalence rates of manic depressive illness when compared to surveys of white patient populations. In addition, it was found that the demographic characteristics of this subgroup of manic depressive patients were very similar to those found in white manic depressive patients. Yet, when the past histories of these black manic depressive patients were reviewed, there were large numbers of patients who received a diagnosis of schizophrenia and, thus, were not considered for treatment with lithium.

Adult↗
PubMed1981

Security procedures in a psychiatric emergency service.

The issue of violence in the mental health setting has recently begun to gain attention in the literature. As there is not enough research on this issue to draw conclusions as to the frequency of violence in mental health settings, there is a need to gather empirical data on the frequency of violence in various settings and to investigate the causes and management of this phenomenon. This article seeks to assess the prevalence of violence and potential violence in an inner-city psychiatric emergency service using several parameters as indicators. In addition, the article seeks to outline skills necessary for the management of violent patients which includes the recognition of potentially violent behavior, a hierarchy of management techniques to prevent the occurrence of violence, and techniques specifically designed to stop violence without causing patient or staff harm. Various etiologies of violence in mental health settings are discussed and a cognitive hierarchy of aggression is presented. Legal and ethical issues surrounding the concept of forcing patients to accept treatment on the basis of their dangerousness are discussed. Finally, the question of a difference in the prevalence of violence between ethnically different patient populations is raised, along with the possible implications of such a difference. Recommendations are made for the management of the potentially violent or violent patient.

Emergency Services, Psychiatric↗