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1.
Reprod Fertil Dev ; 31(2): 294-305, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30099982

ABSTRACT

Blastocoel expansion during embryo development is known to be reliant on the Na+/K+-ATPase pump, but little is known about the relative contribution of active (Na+/K+-ATPase pump) and facilitated diffusion (aquaporins) water transport during blastocoel re-expansion after vitrification. The aims of this study were to examine potential effects of artificial blastocoel collapse (ABC) on markers of embryo stress and the contribution of active and facilitated diffusion water transport mechanisms to blastocoel re-expansion. Day 5 mouse embryos were vitrified using either a standard protocol, laser pulse ABC, a hyperosmotic sucrose ABC protocol or both laser pulse and sucrose. Using real-time polymerase chain reaction, no differences were found in the gene expression of the endoplasmic reticulum (ER) stress markers activating transcription factor 4 (Atf4) or heat shock protein 90-alpha (Hsp90α) 2h after warming. Similarly, expression of the Na+/K+-ATPase pump gene, ATPase, Na+/K+ transporting, beta 1 polypeptide (Atp1b1) and protein did not differ between groups. Aquaporin 8 (Aqp8) gene expression was significantly lower in the laser+sucrose ABC group than in fresh controls, and aquaporin 3 (Aqp3) expression significantly higher in standard vitrified embryos compared with all other groups. Ouabain, a potent and specific Na+/K+-ATPase pump inhibitor, inhibited blastocoel re-expansion in both standard protocol- and laser ABC-vitrified embryos, reducing both groups to the same rate of re-expansion 3h after warming. These results demonstrate that ABC before vitrification does not alter mRNA or protein expression of Na+/K+-ATPase, or mRNA levels of ER stress genes Atf4 and Hsp90α. Activity of the pump may be increased in ABC embryos, with potential compensation by AQP3 when it is compromised.


Subject(s)
Blastocyst/cytology , Endoplasmic Reticulum Stress/physiology , Gene Expression Regulation, Developmental , Sodium-Potassium-Exchanging ATPase/metabolism , Vitrification , Animals , Blastocyst/metabolism , Cryopreservation/methods , Embryonic Development/physiology , Female , Gene Expression , Mice
2.
Reprod Fertil Dev ; 30(8): 1049-1054, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29381876

ABSTRACT

Research in reproductive science is essential to promote new developments in reproductive health and medicine, agriculture and conservation. The Society for Reproductive Biology (SRB) 2017 conference held in Perth (WA, Australia) provided a valuable update on current research programs in Australia and New Zealand. This conference review delivers a dedicated summary of significant questions, emerging concepts and innovative technologies presented in the symposia. This research demonstrates significant advances in the identification of precursors for a healthy pregnancy, birth and child, and discusses how these factors can influence disease risk. A key theme included preconception parental health and its effect on gametogenesis, embryo and fetal development and placental function. In addition, the perturbation of key developmental checkpoints was shown to contribute to a variety of pathological states that have the capacity to affect health and fertility. Importantly, the symposia discussed in this review emphasised the role of reproductive biology as a conduit for understanding the transmission of non-communicable diseases, such as metabolic disorders and cancers. The research presented at SRB 2017 has revealed key findings that have the prospect to change not only the fertility of the present generation, but also the health and reproductive capacity of future generations.


Subject(s)
Reproduction , Research , Animals , Australia , Female , Fertility , Humans , New Zealand , Parturition , Pregnancy
3.
Psychol Med ; 45(3): 647-61, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25272965

ABSTRACT

BACKGROUND: Patients with anxiety disorders suffer marked functional impairment in their activities of daily living. Many studies have documented that improvements in anxiety symptom severity predict functioning improvements. However, no studies have investigated how improvements in functioning simultaneously predict symptom reduction. We hypothesized that symptom levels at a given time point will predict functioning at the subsequent time point, and simultaneously that functioning at a given time point will predict symptom levels at a subsequent time point. METHOD: Patients were recruited from primary-care centers for the Coordinated Anxiety Learning and Management (CALM) study and were randomized to receive either computer-assisted cognitive-behavioral therapy and/or medication management (ITV) or usual care (UC). A cross-lagged panel design examined the relationship between functional impairment and anxiety and depression symptom severity at baseline, 6-, 12-, and 18-month follow-up assessments. RESULTS: Prospective prediction of functioning from symptoms and symptoms from functioning were both important in modeling these associations. Anxiety and depression predicted functioning as strongly as functioning predicted anxiety and depression. There were some differences in these associations between UC and ITV. Where differences emerged, the UC group was best modeled with prospective paths predicting functioning from symptoms, whereas symptoms and functioning were both important predictors in the ITV group. CONCLUSIONS: Treatment outcome is best captured by measures of functional impairment as well as symptom severity. Implications for treatment are discussed, as well as future directions of research.


Subject(s)
Anti-Anxiety Agents/therapeutic use , Anxiety Disorders/therapy , Cognitive Behavioral Therapy/methods , Primary Health Care , Activities of Daily Living , Adult , Executive Function , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Severity of Illness Index , Treatment Outcome
4.
J Psychopathol Behav Assess ; 35(2): 254-263, 2013 06 01.
Article in English | MEDLINE | ID: mdl-23729989

ABSTRACT

The present study examined rates of trauma exposure, clinical characteristics associated with trauma exposure, and the effect of trauma exposure on treatment outcome in a large sample of primary care patients without posttraumatic stress disorder (PTSD). Individuals without PTSD (N = 1263) treated as part of the CALM program (Roy-Byrne et al., 2010) were assessed for presence of trauma exposure. Those with and without trauma exposure were compared on baseline demographic and diagnostic information, symptom severity, and responder status six months after beginning treatment. Trauma-exposed individuals (N = 662, 53%) were more likely to meet diagnostic criteria for Obsessive Compulsive Disorder and had higher levels of somatic symptoms at baseline. Individuals with and without trauma exposure did not differ significantly on severity of anxiety, depression, or mental health functioning at baseline. Trauma exposure did not significantly impact treatment response. Findings suggest that adverse effects of trauma exposure in those without PTSD may include OCD and somatic anxiety symptoms. Treatment did not appear to be adversely impacted by trauma exposure. Thus, although trauma exposure is prevalent in primary care samples, results suggest that treatment of the presenting anxiety disorder is effective irrespective of trauma history.

5.
Psychol Med ; 40(12): 2059-68, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20146834

ABSTRACT

BACKGROUND: Anxiety disorders are the most prevalent mental health disorders and are associated with substantial disability and reduced well-being. It is unknown whether the relative impact of different anxiety disorders is due to the anxiety disorder itself or to the co-occurrence with other anxiety disorders. This study compared the functional impact of combinations of anxiety disorders in primary care out-patients. METHOD: A total of 1004 patients with panic disorder (PD), generalized anxiety disorder (GAD), social anxiety disorder (SAD) or post-traumatic stress disorder (PTSD) provided data on their mental and physical functioning, and disability. Multivariate regressions compared functional levels for patients with different numbers and combinations of disorders. RESULTS: Of the patients, 42% had one anxiety disorder only, 38% two, 16% three and 3% all four. There were few relative differences in functioning among patients with only one anxiety disorder, although those with SAD were most restricted in their work, social and home activities and those with GAD were the least impaired. Functioning levels tended to deteriorate as co-morbidity increased. CONCLUSIONS: Of the four anxiety disorders examined, GAD appears to be the least disabling, although they all have more in common than in distinction when it comes to functional impairment. A focus on unique effects of specific anxiety disorders is inadequate, as it fails to address the more pervasive impairment associated with multiple anxiety disorders, which is the modal presentation in primary care.


Subject(s)
Anxiety Disorders/physiopathology , Disabled Persons/psychology , Stress Disorders, Post-Traumatic/psychology , Activities of Daily Living , Adult , Disabled Persons/classification , Employment , Female , Humans , Male , Outpatients , Primary Health Care , Social Behavior
6.
Psychol Med ; 40(7): 1125-36, 2010 Jul.
Article in English | MEDLINE | ID: mdl-19903363

ABSTRACT

BACKGROUND: Several theories have posited a common internalizing factor to help account for the relationship between mood and anxiety disorders. These disorders are often co-morbid and strongly covary. Other theories and data suggest that personality traits may account, at least in part, for co-morbidity between depression and anxiety. The present study examined the relationship between neuroticism and an internalizing dimension common to mood and anxiety disorders. METHOD: A sample of ethnically diverse adolescents (n=621) completed self-report and peer-report measures of neuroticism. Participants also completed the Structured Clinical Interview for DSM-IV (SCID). RESULTS: Structural equation modeling showed that a single internalizing factor was common to lifetime diagnosis of mood and anxiety disorders, and this internalizing factor was strongly correlated with neuroticism. Neuroticism had a stronger correlation with an internalizing factor (r=0.98) than with a substance use factor (r=0.29). Therefore, neuroticism showed both convergent and discriminant validity. CONCLUSIONS: These results provide further evidence that neuroticism is a necessary factor in structural theories of mood and anxiety disorders. In this study, the correlation between internalizing psychopathology and neuroticism approached 1.0, suggesting that neuroticism may be the core of internalizing psychopathology. Future studies are needed to examine this possibility in other populations, and to replicate our findings.


Subject(s)
Neurotic Disorders/diagnosis , Adolescent , Anxiety Disorders/diagnosis , Anxiety Disorders/psychology , Diagnosis, Differential , Diagnostic and Statistical Manual of Mental Disorders , Ethnicity/statistics & numerical data , Female , Humans , Male , Mood Disorders/diagnosis , Mood Disorders/psychology , Neurotic Disorders/psychology , Surveys and Questionnaires
7.
Neurosurgery ; 42(6): 1318-24; discussion 1324-5, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9632191

ABSTRACT

OBJECTIVE: Both motor and sensory neurological deficits have been reported after decompression and instrumentation of the lumbosacral spine. In this report, we describe a simple and effective method by which sensory and motor functions can be monitored simultaneously, using somatosensory evoked potentials (SSEP), spontaneous electromyographic (EMG) activity, and compound muscle action potential monitoring. The concomitant use of these monitoring techniques allows ongoing functional evaluation of the cauda equina and spinal cord during patient positioning, surgery, wound closure, and anesthetic emergence. METHODS: SSEPs were recorded continuously in response to peroneal or tibial nerve stimulation. EMG activity (both spontaneous and evoked) was recorded bilaterally from appropriate lower extremity muscle groups. All recordings (SSEP and EMG activity recordings) were obtained, stored, and reviewed simultaneously. RESULTS: SSEPs and EMG activity were simultaneously recorded for 44 patients. All patients in the study underwent surgical procedures to decompress and stabilize the lumbosacral spine, using pedicle screw instrumentation. In two cases, changes in SSEPs and spontaneous EMG activity were noted and were correlated with postoperative patient complaints. CONCLUSION: This report describes the concomitant use of powerful and simple tools that provide immediate, "early-warning" feedback to the surgical team concerning the sensory and motor functioning of the spinal cord and cauda equina. In addition, compound muscle action potential recording provides a tool for the identification of both levels and structures in the lumbosacral spine.


Subject(s)
Electromyography , Evoked Potentials, Somatosensory , Lumbar Vertebrae/surgery , Monitoring, Intraoperative/methods , Orthopedic Fixation Devices , Spinal Cord/physiopathology , Action Potentials/physiology , Adult , Aged , Aged, 80 and over , Bone Screws , Evoked Potentials, Somatosensory/physiology , Female , Humans , Male , Middle Aged , Muscle, Skeletal/physiopathology
8.
Med Hypotheses ; 50(2): 147-54, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9572570

ABSTRACT

The purpose of this paper is to present a model for removing antidromically activated afferent input from cervically elicited neurogenic motor evoked potentials (nMEPs). nMEPs have recently been used clinically, purportedly for monitoring spinal cord motor function, during spine surgery. However, the nMEP response may be due, in part or in whole, to neural signals travelling through sensory rather than motor pathways. This complicates nMEP interpretation and may lead to false conclusions about the status of motor tracts and postoperative motor function. Moreover, transcranial stimulation techniques may also contain similar afferent contamination. Here I suggest a protocol for intraoperative use that should effectively remove such afferent contamination via an afferent action potential collision technique.


Subject(s)
Evoked Potentials, Motor/physiology , Afferent Pathways/physiology , Animals , Electrodes , Evoked Potentials, Somatosensory/physiology , Humans , Models, Neurological , Muscle Relaxation , Neck , Neural Conduction/physiology , Neurophysiology/methods , Psychomotor Performance/physiology , Reflex/physiology , Spinal Cord/physiology , Spinal Cord/surgery
9.
Arch Phys Med Rehabil ; 79(2): 226-9, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9474009

ABSTRACT

This case report describes the intraoperative improvement of somatosensory evoked potentials (SEPs) during the removal of a broached pedicle screw that had been placed in an unmonitored procedure 1 month earlier. Postoperatively, there was improved neurologic function and reversal of the neurologic deficit that had been caused by the first procedure. To our knowledge, this is the first report of a correlation of intraoperative SEP improvement with improved postoperative neurologic function after neurologic deficit because of nerve irritation or compression from a pedicle screw. Nerve damage occurs in about 15% of patients who undergo instrumentation after lumbar fusion. The potential utility of neurophysiologic methods during initial screw placement is suggested and supported, as proper use of such intraoperative tools may have prevented the need for the second procedure.


Subject(s)
Bone Screws/adverse effects , Evoked Potentials, Somatosensory , Lumbar Vertebrae/surgery , Nerve Compression Syndromes/etiology , Adult , Female , Humans , Intraoperative Period , Lumbar Vertebrae/diagnostic imaging , Nerve Compression Syndromes/surgery , Radiography
10.
J Clin Psychol ; 53(8): 895-903, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9403392

ABSTRACT

Intergenerational transmission of war experiences was assessed using a modified Stroop task. Adult children of war veterans and those of nonveterans named the colors in which war related words were printed. They also named the colors of neutral, positive, and OCD related words in addition to color naming a series of zeros contained on a control card. All participants completed the MMPI-II PTSD Scale, the Impact of Event Scale, and a demographic questionnaire. A statistically significant difference between the children of veterans and nonveterans was found only on the Stroop card containing war related words. Results suggest that the modified Stroop task is a sensitive measure that may have value in assessing transmission of war experiences from parents to children.


Subject(s)
Parent-Child Relations , Stress Disorders, Post-Traumatic/psychology , Veterans/psychology , Adolescent , Adult , Color Perception , Female , Humans , Male , Middle Aged , Neuropsychological Tests/standards , Reproducibility of Results , Warfare
11.
J Neurosurg ; 87(3): 397-402, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9285605

ABSTRACT

The neuroanatomical structures that approximate the bony pedicles of the lumbar spine allow little room for technical error or compromise of the bone during pedicle screw insertion. Currently available neurophysiological monitoring techniques detect compromised bone and nerve root injury after it occurs. The purpose of this prospective study is to evaluate the reliability and efficacy of a unique neurophysiological monitoring technique. This technique provides immediate evaluation of pedicle cortical bone integrity in patients undergoing lumbar fusion with instrumentation by using electrified surgical instruments throughout the pedicle screw fusion procedure. Spontaneous electromyographic (EMG) activity was also monitored. Intraoperative evoked EMG stimulation was performed using a pedicle probe and feeler as monopolar stimulators during the insertion of 164 pedicle bone screws in 32 patients. The EMG response to subthreshold stimulation intensities indicated cortical bone compromise. Immediate and conclusive feedback via evoked EMG activity using stimulating pedicle probes in appropriate muscle groups was successful in identifying pedicle cortical bone compromise in four patients. One false-negative evoked EMG study was noted but was identified via spontaneous EMG activity. Intraoperative EMG monitoring alerted the surgeon that redirection of the pedicle probe or screw was necessary to avoid nerve root irritation or injury and served as an early warning system. Evoked EMG stimulation proved to be reliable and efficacious, especially when used in combination with spontaneous EMG. This technique may provide an added safeguard during implant placement procedures at centers where intraoperative neurophysiological monitoring is routinely performed.


Subject(s)
Bone Screws/adverse effects , Electromyography/instrumentation , Evoked Potentials, Motor , Evoked Potentials, Somatosensory , Spinal Fusion/instrumentation , Spinal Nerve Roots/injuries , Spinal Nerve Roots/physiopathology , Adult , Aged , Electromyography/methods , Female , Humans , Male , Middle Aged , Monitoring, Intraoperative/methods , Peripheral Nervous System Diseases/etiology , Peripheral Nervous System Diseases/physiopathology , Peripheral Nervous System Diseases/prevention & control , Prospective Studies , Reproducibility of Results , Spinal Fusion/adverse effects
12.
13.
J Neurosurg ; 87(2): 334-5, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9254103
14.
Neurosurg Focus ; 2(3): e4, 1997 Mar 15.
Article in English | MEDLINE | ID: mdl-15096012

ABSTRACT

Posteroventral pallidotomy (PVP) has received renewed interest as an ablative procedure for the symptomatic treatment of Parkinson's disease. In previous reports, the proximity of the optic tract to the lesion target in the globus pallidus internus has resulted in the occurrence of visual field deficits in as much as 14% of patients. The authors have used intraoperative visual evoked potentials (VEPs) during PVP to reduce this risk. All procedures were performed in awake patients. Flash stimuli were delivered to each eye via fiberoptic sources. Baseline flash VEPs were recorded at O1/Cz (left visual cortex to vertex), Oz/Cz (midline visual cortex to vertex), and O2/Cz (right visual cortex to vertex) for OS, OU, and OD stimulation. Epochs were acquired before and after localization, after macroelectrode stimulation, after temporary thermal lesioning, and after permanent thermal lesioning. Forty-seven patients underwent a total of 59 procedures. Visual evoked potentials were recorded reproducibly in all patients. In 11 procedures, VEP changes were reported, including six amplitude changes (10-80%), six latency shifts (3-10 msec), and one report of "variability." In four procedures, VEP changes prompted a change in target coordinates. One false-positive and one false-negative VEP change were encountered. The only confirmed visual deficit was a superior quadrantanopsia, present on formal fields, but clinically asymptomatic. The authors conclude that VEPs may be useful for procedures performed in the awake patient because of the lack of anesthetic-induced variability. The 1.7% visual morbidity reported here (one in 59 patients) compares favorably with other series using microelectrodes. Visual evoked potentials may be a useful monitoring technique to reduce the incidence of clinically significant visual morbidity during pallidotomy, especially during formal lesioning of the ventral pallidum adjacent to the optic tract.

15.
Spine (Phila Pa 1976) ; 22(3): 334-43, 1997 Feb 01.
Article in English | MEDLINE | ID: mdl-9051896

ABSTRACT

STUDY DESIGN: A prospective review was done of a new intraoperative technique developed to detect and prevent neurologic compromise during pedicle screw insertion. OBJECTIVES: To describe in sufficient detail the technique of persistently electrified pedicle stimulation instruments, so that this technique will be available generally to all clinical neurophysiologists and spine surgeons; and to demonstrate the use, typical results, interpretation, and protocol of the technique. SUMMARY AND BACKGROUND DATA: Fusion techniques that use pedicle instrumentation have the potential to cause nerve root injury. Several authors have proposed imaging and neurophysiologic methods to improve outcome. The present method represents a significant theoretical departure and advance from previously reported methods. METHODS: All relevant instruments used during pedicle instrumentation were converted easily, inexpensively, and quickly into monopolar stimulators with appropriate stimulus voltages to identify broaches of pedicle bone via evoked-electromyograms from relevant muscle groups. RESULTS: The persistently electrified pedicle stimulation instrument technique provided accurate intraoperative neurophysiologic information concerning pedicle, integrity in the patients studied. The protocol is standardized and adaptable easily, inexpensively, and quickly to most clinical applications. CONCLUSIONS: The persistently electrified pedicle stimulation instrument technique described here is useful for monitoring instrumented lumbar fusion procedures. The use of this protocol may help confirm intraosseous placement of pedicle screws and prevent neurologic injury.


Subject(s)
Bone Screws , Electromyography/instrumentation , Spinal Fusion , Electric Stimulation , Electromyography/methods , Evaluation Studies as Topic , Evoked Potentials, Somatosensory , False Negative Reactions , False Positive Reactions , Humans , Intraoperative Period , Prospective Studies , Spinal Fractures/surgery
16.
Med Hypotheses ; 46(6): 577-9, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8803945

ABSTRACT

The purpose of this paper is to present the hypothesis that cervically elicited motor evoked potentials which have recently gained clinical acceptance for monitoring spinal cord motor function during spine surgery, may be due, in part or in whole, to neural signals travelling through sensory rather than motor tracts. If true, then the interpretation of cervically elicited motor evoked potentials may lead to false conclusions about the status of motor tracts and postoperative motor function.


Subject(s)
Evoked Potentials, Motor , Evoked Potentials, Somatosensory , Models, Neurological , Neurons, Afferent/physiology , Spine/surgery , Electroencephalography , Humans , Monitoring, Intraoperative , Motor Neurons/physiology , Reproducibility of Results
17.
Brain Res ; 630(1-2): 345-8, 1993 Dec 10.
Article in English | MEDLINE | ID: mdl-8118704

ABSTRACT

Retrospective analysis of somal electrophysiology from intracellularly recorded, physiologically identified afferents demonstrates that neural nets can be readily trained to identify the type of peripheral receptor supplied. Specifically, cat spinal ganglion somata could be identified as innervating muscle spindles, hairs or high-threshold mechanoreceptors. Further, both hair afferents and high-threshold mechanoreceptors could be separated into three distinct subclasses. The neural net sorting reported here utilizes only the electrophysiological properties of the somata plus conduction velocity and can with this information alone predict the functional properties of the sensory endings. Interestingly, neural net sorting could also distinguish between different types of hair afferents (or nociceptors), even when conduction velocity information was ignored. It is suggested that neural nets, in combination with computer-controlled data-acquisition systems, could greatly increase investigator efficiency and decrease the number of animals needed to demonstrate specific phenomena, such as drug effects on particular cell types. A double-edged sword of increased investigator efficiency and decreased animal usage may be of particular usefulness in the present socio-political research arena.


Subject(s)
Ganglia, Spinal/physiology , Neural Networks, Computer , Neurons/physiology , Sensory Receptor Cells/physiology , Action Potentials/physiology , Animals , Cats , Ganglia, Spinal/cytology , Retrospective Studies
18.
Methods Inf Med ; 30(4): 299-303, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1762584

ABSTRACT

A test for nonrandom patterns in populations of "cells" of binary attributes is formulated for applications in settings where it is impossible or impractical to completely specify the adjacency matrix, as in circumstances involving enormous numbers of cells and/or censored data. Applications are made to problems concerning spatial distributions of specially labeled cells in nervous system research.


Subject(s)
Cluster Analysis , Ganglia, Spinal/physiology , Models, Neurological , Animals , Cats , Chick Embryo , Data Interpretation, Statistical , Neurons/physiology
19.
J Comp Neurol ; 308(1): 28-41, 1991 Jun 01.
Article in English | MEDLINE | ID: mdl-1874980

ABSTRACT

Anatomical studies using retrograde neuronal tracers were carried out to identify pudendal motoneurons and putative lumbosacral interneurons involved in the generation of penile reflexes in the adult male rat (Sprague-Dawley). In agreement with previous studies, injection of the direct neuronal tracers, horseradish peroxidase or fluoro-gold, into the left M. bulbospongiosus (dorsal division) resulted in direct retrograde labeling of motoneurons only in the ipsilateral dorsomedial (DM) nucleus. In contrast, similar injections of the transneuronal tracer, wheat germ agglutinin (WGA), resulted in direct retrograde labeling of ipsilateral DM motoneurons as well as transneuronal labeling of contralateral DM motoneurons and of bilaterally located putative spinal interneurons. The WGA-labeling was determined to be transneuronal by a series of nerve cut experiments. The direct retrograde WGA-labeling of ipsilateral DM motoneurons and the transneuronal WGA-labeling of contralateral DM motoneurons and bilateral putative spinal interneurons occurred with different time courses. Direct retrograde labeling of ipsilateral DM motoneurons was seen at 20 hours survival and persisted up to 7 days survival. The shortest survival period for detecting transneuronal labeling of contralateral DM motoneurons and putative interneurons was 2 days. Transneuronal WGA-labeling of contralateral DM motoneurons was transient in that the intensity of label increased from 2 to 3 days survival but was markedly reduced at 7 days survival. At the same time, the number of WGA-labeled putative interneurons increased with longer survival times up to 7 days. WGA-labeled putative interneurons were located primarily in regions receiving dendritic projections from WGA-labeled DM motoneurons and, in particular, 1) the ventral gray matter between the DM and dorsolateral nuclei and 2) near the central canal and extending dorsally to the dorsal gray commissure. The rapid and extensive transneuronal transport between DM nuclei suggests that direct synaptic coupling may mediate coordinated, bilateral activation of DM motoneurons.


Subject(s)
Motor Neurons/ultrastructure , Neurons/ultrastructure , Stilbamidines , Animals , Fluorescent Dyes , Histocytochemistry , Horseradish Peroxidase , Immunohistochemistry , Interneurons/ultrastructure , Male , Perfusion , Perineum/innervation , Rats , Rats, Inbred Strains , Spinal Cord/cytology , Wheat Germ Agglutinins
20.
J Comp Neurol ; 272(4): 365-86, 1988 Jun 22.
Article in English | MEDLINE | ID: mdl-3047184

ABSTRACT

A new method for determining the number of neurons in sectioned tissue is presented. The method does not involve identification of subcellular structures; rather, it uses estimates of the mean diameters of sections of the neuronal somata (with or without nuclei). All such sections are termed profiles. A mathematical model is developed to reconstruct the cell population from a size histogram of the profiles. Although the model is simple, the calculations are numerous and best done on a computer. A program that performs these calculations is provided. We discuss the idealizations on which the model is based and test the method in various ways: on hand- and computer-generated data in which imaginary spheres of known size were sectioned; on two small samples of real cells for which both cell and profile size histograms were available; and on a sample of potatoes, sliced by hand. In every case the estimate was within 10% of the actual number of cells (or potatoes). The method is robust in that it is relatively insensitive to section thickness, sample size, somal morphology, and observer error with respect to missing the small or thin profiles from any given cell. Results from the present model are compared to those obtained by using other cell count correction schemes that are currently employed. We call our method recursive translation.


Subject(s)
Cell Count/methods , Models, Biological , Neurons/cytology , Animals , Cats , Computer Simulation , Dendrites/ultrastructure , Evaluation Studies as Topic , Feedback , Ganglia, Spinal/cytology , Histological Techniques , Neck , Neurons/ultrastructure , Software , Spinal Cord/cytology , Spinal Cord/ultrastructure , Terminology as Topic
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