Humans ; Locomotion ; Mesencephalon ; Midbrain Reticular Formation ; Parkinson Disease

Medullar respiratory centers are composed of ventral and dorsal groups. A direct infarction to their structure could lead to a complete loss of respiratory drive, despite unilateral brainstem lesion is rarely associated with central respiratory dysfunction. A 70-year-old man was admitted with sudden dizziness and disequilibrium without motor weakness. Brain MRI (diffuse weight image) shows high signals intensities on left PICA territory of cerebellum and medulla oblongata including reticular formation, nucleus of tractus solitarius, nucleus ambiguus, and nucleus retroambiguus but sparing corticospinal and corticobulbar pathway. On 3rd hospital day, he had a complete loss of respiratory drive involving both autonomic and voluntary components. He didn't get the respiratory drive during CO2 retention while his consciousness and motor power were preserved.
Aged ; Brain ; Brain Stem ; Cerebellum ; Consciousness ; Dizziness ; Humans ; Infarction* ; Magnetic Resonance Imaging ; Medulla Oblongata ; Pica* ; Respiratory Center ; Respiratory Insufficiency* ; Reticular Formation

Medullary respiratory centers are composed of two respiratory groups: dorsal and ventral. A dorsal respiratory group consists primarily of inspiratory neurons. A ventral respiratory group consists both of inspiratory and expiratory neurons. A direct infarction of their structure may lead to a complete loss of respiratory drive involving both automatic and voluntary components. A 78-year-old man was admitted with sudden dysarthria, dizziness, and bilateral ophthalmoplegia. On the second and third hospital day, he nearly had a complete loss of respiratory drive involving both automatic and voluntary components. He did not get the respiratory drive during CO2 retention while consciousness and motor were preserved. Brain MRI showed unilateral lesions involving the medullary reticular formation, nucleus tractus solitarius, nucleus ambiguus, and nucleus retroambiguus but sparing the corticospinal tract. Unilateral medullary infarction may lead to severe respiratory failures not limited to automatic responses, which differentiates it from Ondine's curse.
Aged ; Brain ; Cerebral Infarction ; Consciousness ; Dizziness ; Dysarthria ; Humans ; Infarction ; Magnetic Resonance Imaging ; Medulla Oblongata ; Neurons ; Ophthalmoplegia ; Pyramidal Tracts ; Respiratory Center ; Respiratory Insufficiency* ; Reticular Formation ; Solitary Nucleus

The pathway and mechanism of convergence movement of eyes are not exactly confirmed at now. But, according to the recent neurophysiologic studies, the convergence cells was found in an area of the mesencephalic reticular formation just dorsal and lateral to the oculomotor nucleus and rostral to the superior colliculus. I experienced four patients, who complained diplopia due to unilateral convergence palsy. These cases of unilateral convergence palsy suggests that the Rt. Convergence cells and the Lt. Convergence cells in the mesencephalic reticular formation has independent pathway to ipsialteral medial rectus motoneuron nucleus.
Diplopia ; Humans ; Paralysis* ; Reticular Formation ; Superior Colliculi

Substantial evidence has suggested that deep brain stimulation of the cuneiform nucleus has become a remarkable treatment option for intractable pain, but the possible mechanism is poorly understood. Using a melanocortin-4 receptor (MC4R)-green fluorescent protein (GFP) reporter knockin mouse, we showed that a large number of MC4R-GFP-positive neurons were expressed in the cuneiform nucleus. Immunofluorescence revealed that approximately 40%-50% of MC4R-GFP-positive neurons expressed mu opioid receptors, indicating that they were opioidergic signaling. Our findings support the hypothesis that MC4R expression in the cuneiform nucleus is involved in the modulation of opioidergic signaling.
Animals ; Gene Expression Regulation ; Gene Knock-In Techniques ; Genes, Reporter ; Green Fluorescent Proteins ; genetics ; metabolism ; Mice ; Mice, Transgenic ; Microtomy ; Midbrain Reticular Formation ; cytology ; metabolism ; Neurons ; cytology ; metabolism ; Receptor, Melanocortin, Type 4 ; genetics ; metabolism ; Receptors, Opioid, mu ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; Signal Transduction

To clarify neuronal connection of the medial rectus muscle at brain stem, Bartha strain of the psecudorabies virus(PRV-Ba) and cholera toxin-horeserdish peroxidase(CT-HRP) was injected into medial rectus muscle of the rat. About 84 hours after PRV or CT-HRP injection, the brain was removed and processed immunohistochemical stain for PRV-Ba and neurohistochemical stain for CT-HRP using tetramethyl benzidine. The CT-HRP positive reaction was only present in ipsilateral oculomotor nucleus, contralateral abducence nucleus and bilaterally in rostral interstitial nucleus of medial longitudinal fasciculus, olivary pretectal nucleus, medial and superior vestibular nucleus, nucleus prepositus hypoglossi, prerubral field, nucleus Darkschewitsch, lateral substantia nigra, terminal nucleus of accessory nucleus, dorsal raphenucleus, locus ceruleus and pontime reticular formation. This study confirmed that both oculomotor nucleus and abducence nucleus were connected with each other through the medial longitudinal fasciculus, and neuronal connection of the medial rectus muscle in the rat brain stem.
Animals ; Brain Stem* ; Brain* ; Cholera ; Locus Coeruleus ; Neurons ; Rats* ; Reticular Formation ; Substantia Nigra

PURPOSE: To report a case of bilateral horizontal gaze palsy associated with pontine hemorrhage. METHODS: A 51-year-old man developed a sudden decrease in consciousness. Computed tomography reveal a pontine hemorrhage and infarctions of both basal ganglia. The mentality was recovered after conservative treatment, but he complained of difficulty in moving his eyes. We performed ophthalmic and radiologic evaluations to confirm a diagnosis of bilateral horizontal gaze palsy and to reveal the condition. RESULTS: On ophthalmic examination, his eye showed complete bilateral horizontal gaze palsy, but convergence and vertical eye movements were normal. Radiologic evaluation revealed a pontine hemorrhage, and the hemorrhagic area was consistent the bilateral paramedian pontine reticular formation (PPRF).
Basal Ganglia ; Consciousness ; Diagnosis ; Eye Movements ; Hemorrhage* ; Humans ; Infarction ; Middle Aged ; Paralysis* ; Reticular Formation

The study of blink reflexes was carried out to demonstrate the correlations, if there were, between the stage of diffuse axonal injury(DAI) and the abnormality of blink reflexes. The blink reflex was recorded in 20 healthy adult subjects and 22 patients with DAI who were classified according to Adams' classification(DAI I; 7, DAI II; 9 and DAI III; 6). The latencies and amplitudes of R1 and R2 in patients with DAI were compared with those of healthy subjects. The results were as follows; 1) In 20 subjects of patient group, the latencies of R1 were all within a normal range. In 2 subjects, the difference in latencies between the two sides was above 1.4 msec. 2) In 15 subjects, R2 was absent or delayed, and reduced in the size of amplitude in all. Nine were affected bilaterally, and 4 were unilaterally. 3) Seventy one percent of patients in each stage represented abnormal findings. 4) There were no correlations between the DAI stage and the blink reflex. This study demonstrated that the polysynaptic R2 was more profoundly suppressed than the oligosynaptic R1 in a diffuse axonal injury because of a loss or decrease of suprapontine facillitation, which influenced the trigeminal spinal complex and the interneuron of lateral reticular formation.
Adult ; Axons ; Blinking* ; Diffuse Axonal Injury* ; Humans ; Interneurons ; Reference Values ; Reticular Formation

The brain stem consists of medulla oblongta, pons and midbrain. It is sited in posterior cranial fossa. It contains numerous intrinsic neuron cell bodies and their processes, some of which are the brain stem homologues of spinal neuronal groups. These include the sites of termination and cells of origin of axons that enter or leave the brain stem through the cranial nerves. Cranial nerves provide sensory, motor and autonomic innervations of structures that are mostly in the head and neck. The reticular formation is an extensive network of neurons that extends throughout the length of brain stem and is continuous rostrally to diencephalon and caudally to its spinal counterpart. Clinically, damage to the brain stem is often devastating and life threatening. This is because it is a structurally and functionally compact region. Therefore, it is important to build basic knowledge about neuroanatomy of brain stem.
Axons ; Brain Stem* ; Cranial Fossa, Posterior ; Cranial Nerves ; Diencephalon ; Head ; Mesencephalon ; Neck ; Neuroanatomy* ; Neurons ; Pons ; Reticular Formation

STATEMENT OF PROBLEM: The importance of fixture design and surface treatment. PURPOSE: The clinical success of dental implants is affected by many factors such like as degree of osseointegration, the effective load dispersion for the prostheses, and a lot of attempts have been made to overcome the difficulties. In this study, efforts were made to find the possibility of clinical acceptance of the dental implants of newly designed surface and resorbable blast media surcace. MATERIALS AND METHODS: In this study, two groups of custom-made, screw-shaped implants were prepared. Tthe first with the consisting of Branemark clone design and the other with the new design. These implants were divided into four groups according to the kinds of surface treatment. Four implants(AVANA., Osstem, Busan, Korea) of each group were installed in twenty rabbits. Group A was consisted of Branemark clone implant left as machined, Group B with Branemark clone implants with RBM(Resorbable blast media) surface, Group C with newly designed implants left as machined and Group D with newly designed implants with RBM surface. One of the twenty rabbits died from inflammation and the observation was made for six weeks. Specimens from four groups were observed using scanning electron microscopy with 40, 100, 1000 magnification power and microsurface structures were measured by white-light scanning interferometry for three dimensional surface roughness measurements(Accura 2000., Intek-Plus, Korea.). Removal torque was measured in 17 rabbits using digital torque gauge(MGT 12R, Mark-10 corp., NY, U.S.A.) immediately after the sacrifice and two rabbits were used for the histologic preparation(EXAKT 310., Heraeus Kulzer, Wehrheim, Germany) of specimens and observed under light microscope. Resonance frequency measurement(Osstell(R)) was taken with the 19 rabbits at the beginning of the implant fixation and immediately after the sacrifice. RESULTS: Following results were taken from the experiment. 1. The surface of the RBM implants as seen with SEM had rough and irregular pattern with reticular formation compared to that of turned specimens showing different surface topographies. 2. The newly designed implant with RBM surface had high removal torque value among four groups with no statistical significance. The average removal torque was 49.95+/-6.70Ncm in Group A, 51.15+/-4.40Ncm in Group B, 50.78+/-9.37Ncm in Group C, 51.09+/-4.69Ncm in Group D. 3. The RFA values were 70.8+/-4.3Hz in Group A, 71.8+/-3.1Hz in Group B, 70.9+/-2.5Hz, 72.7+/-2.5Hz in Group D. Higher values were noted in the groups which had surface treatment compared to the untreated groups with no statistical significance. 4. The results from the histomorphometric evaluation showed a mean percentage of bone-toimplant contact of 45+/-0.5% in Group A, 55+/-3% in Group B, 49.5+/-0.5% in Group C, and 55+/-3% in Group D. Quite amount of newly formed bone were observed at the surface RBM-treated implants in bone marrow space.
Bone Marrow ; Busan ; Clone Cells ; Dental Implants ; Inflammation ; Interferometry ; Microscopy, Electron, Scanning ; Osseointegration ; Prostheses and Implants ; Rabbits ; Reticular Formation ; Tibia* ; Torque*