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Biomedical subjects

R C Kim

Publications and source records attributed to R C Kim.

At least 37 records · Page 2Linked to original sources
PubMed1988

Non-traumatic ischaemic myelopathy: a review of 25 cases.

The causes of ischaemic myelopathy are described in 25 patients. Nine developed following surgical manipulation or traumatic laceration of the aorta, 1 following intercostal artery ligation, 3 following aortic aneurysm dissection, 2 following myocardial infarction and/or cardiac arrest, 7 in the absence of any specifically identifiable predisposing factors, and 3 in association with decompression sickness. The degree of clinical recovery was greater among those with incomplete spastic (as opposed to complete flaccid) paralysis and among those in whom sensory loss below the level of injury was incomplete. Despite the diversity of mechanisms that may lead to the development of spinal cord ischaemia, structural damage seems in most instances to affect either grey matter or white matter predominantly. Some of the possible reasons for these preferential sites of damage are discussed.

Aorta↗
PubMed1988

Neurogenic true hypertrophy of one calf and atrophy of the other.

Unilateral calf hypertrophy has been described in association with a variety of conditions. Bilateral neurogenic leg weakness with muscle wasting on one side and true hypertrophy on the other, however, has rarely been described. We report a 37-year-old heroin and alcohol abuser with a three-year history of weakness of the left leg and progressive enlargement of the right calf. Computed tomography of the right calf confirmed the presence of true hypertrophy. Electromyography showed denervation in the muscles of both legs. Nerve conduction studies were indicative of peripheral neuropathy. Biopsy of the gastrocnemius muscles revealed the presence of neurogenic atrophy on both sides, with marked hypertrophy and splitting of individual muscle fibers on the right. To our knowledge, this is only the second recorded case showing both muscle atrophy and muscle hypertrophy in response to denervation.

Adult↗
PubMed1988

Myelopathy after the intrathecal administration of hypertonic saline.

The neuropathological effects of intrathecally administered hypertonic saline have not been described previously. We report a patient who, within a day of receiving 20 ml of hypertonic (7.5%) saline intrathecally, developed flaccid paraplegia and complete sensory loss below the umbilicus. Subsequently, there was some transitory return of motor and coarse sensory function. The patient died 16 months after the injection. At autopsy, there was peripherally accentuated loss of myelinated fibers within the spinal cord from T12 downward, as well as dense collagenous thickening of the dorsal leptomeninges from T9 to T11. The findings in this case, coupled with observations made by others, serve to emphasize the need for extreme caution whenever planning any form of intrathecal therapy.

Humans↗
PubMed1986

Disturbances in neuronal migration and laminar cortical organization associated with multicystic encephalopathy in the Pena-Shokeir syndrome.

The Pena-Shokeir syndrome is characterized by intrauterine growth retardation, camptodactyly, multiple ankyloses, facial anomalies and pulmonary hypoplasia. The condition is thought to be inherited in an autosomal recessive fashion. A detailed neuropathological analysis of the brain of a stillborn full-term male infant who exhibited the gross features of the Pena-Shokeir syndrome revealed diffuse bilateral cerebral polymicrogyria associated with multicystic encephalopathy. Abnormal brain development, which was characterized by disturbances in neuronal migration and laminar cortical organization, was clearly associated with changes of an encephaloclastic nature, namely reactive gliosis and infiltration by macrophages. These findings suggest strongly that the Pena-Shokeir syndrome may also result from teratogenic factors such as intrauterine ischemic and/or hypoxic insults to the developing brain.

Abnormalities, Multiple↗
PubMed1985

Plasticity of hippocampal circuitry in Alzheimer's disease.

Two markers of neuronal plasticity were used to compare the response of the human central nervous system to neuronal loss resulting from Alzheimer's disease with the response of rats to a similar neuronal loss induced by lesions. In rats that had received lesions of the entorhinal cortex, axon sprouting of commissural and associational fibers into the denervated molecular layer of the dentate gyrus was paralleled by a spread in the distribution of tritiated kainic acid-binding sites. A similar expansion of kainic acid receptor distribution was observed in hippocampal samples obtained postmortem from patients with Alzheimer's disease. An enhancement of acetylcholinesterase activity in the dentate gyrus molecular layer, indicative of septal afferent sprouting, was also observed in those patients with a minimal loss of cholinergic neurons. These results are evidence that the central nervous system is capable of a plastic response in Alzheimer's disease. Adaptive growth responses occur along with the degenerative events.

Acetylcholinesterase↗
PubMed1985

Prolonged survival after severe traumatic injury limited to the brainstem.

It has been suggested that primary traumatic lesions of the brainstem do not occur in the absence of widespread injury to other parts of the brain. We describe a patient who suffered a severe head injury that left him with paralysis of three extremities and weakness in the fourth. Intellectual function was entirely preserved. Neuropathological examination 39 years after the injury disclosed the presence of a cavitary lesion within the basis pontis. There was no pathological evidence of traumatic injury to any other part of the central nervous system.

Brain↗
PubMed1985

Expression of glial fibrillary acidic protein by immature oligodendroglia and its implications.

Correlative immunocytochemical and electron-microscopic studies of the subpial region of the human fetal spinal cord between 12-18 weeks of ovulation age revealed immature oligodendroglial cells showing immunoreactive GFAP within both the cytoplasm and its processes. By 17-18 weeks, however, GFAP immunoreactivity is no longer evident within such cells. The expression of GFAP by immature oligodendroglial cells in the developing human fetal spinal cord prior to the formation of compact myelin sheaths supports the hypothesis that oligodendrocytes, along with astrocytes, are ultimately derived from radial glial cells.

Cytoplasm↗
PubMed1985

Squamous carcinoma of the nasopharynx.

Nasopharyngeal carcinoma is an unusual neoplasm among squamous cell carcinomas of the head and neck. The tumor is rare in most parts of the world but is strikingly common in several Asian subpopulations, notably Chinese in Hong Kong and Guangdong Province. The Epstein-Barr virus is intimately related to the disease and elicits the formation of antibodies that are useful for diagnosis and follow-up study. The virus has not been conclusively shown to cause nasopharyngeal cancer, however.Histologically, nasopharyngeal carcinoma is anaplastic in 75% of cases and better differentiated in 25% of patients. All tumors are treated by high-dose irradiation to the primary site and both sides of the neck. Surgical treatment, in the neck only, is reserved for irradiation failures. The prognosis is better in patients younger than 40 years, in patients without clinical cervical nodal involvement and, unexpectedly, in patients with anaplastic tumors.

Adult↗
PubMed1984

Expression of glial fibrillary acidic protein in immature oligodendroglia.

In the human fetal spinal cord at 15 to 16 weeks, glial fibrillary acidic protein (GFAP) was demonstrated within the cytoplasm and processes of cells having the cytological, ultrastructural, and immunocytochemical features of oligodendrocytes--including processes that extend into and contribute to the formation of myelin sheaths. By 17 to 18 weeks, however, GFAP immunoreactivity was no longer evident within such cells. Thus GFAP is expressed by myelin-forming oligodendroglia early in their development.

Cytoplasm↗
PubMed1984

CNS infection and bacteremia due to clostridium septicum.

Central nervous system infection with Clostridium septicum is rare. We report two fulminant cases of such infection with accompanying bacteremia. The presence of extensive brain necrosis was striking in our two cases. The association of C septicum bacteremia with hematologic disease, and with solid tumors, was present in our cases. We conclude that C septicum should be considered as a potential cause of life-threatening bacteremia and meningitis in the compromised host.

Adult↗
PubMed1984

Nonhemorrhagic venous infarction of the spinal cord.

A 71-year-old man experienced gradually progressive leg weakness, urinary retention, and mild loss of sensation in dermatomes T8 through T12 bilaterally. After 5 to 6 weeks of illness, he developed flaccid paraplegia and sensory loss below T8. He died 16 weeks after onset of neurological symptoms. Neuropathologically, there was widespread, subtotal necrosis of the spinal cord, largely of nonhemorrhagic character, from T8 downward. Dorsal and anterior median spinal veins were occluded by a partially organized thrombus. Comparison of this case with 19 previously recorded examples of venous infarction of the spinal cord (8 hemorrhagic, 7 nonhemorrhagic, and 4 embolic) suggests major differences in clinical presentation, rate of progression, and length of survival among the three groups.

Aged↗
PubMed1984

The comparative effects of methylmercuric chloride and mercuric chloride upon DNA synthesis in mouse fetal astrocytes in vitro.

The relative effects of direct exposure to methylmercuric chloride (MMC) and mercuric chloride (MC) upon [3H]thymidine incorporation were determined using cultured mouse fetal astrocytes. The labeling indices of cells exposed to MMC were significantly lower than those of cells exposed to equimolar concentrations of MC. These results indicate that on a mole-for-mole basis, MMC is much more deleterious upon DNA synthesis of mouse fetal astrocytes than those of MC.

Animals↗
PubMed1983

Prenatal symmetrical thalamic degeneration with flexion spasticity at birth.

The unusual occurrence of spasticity at birth with symmetrical thalamic damage was found in a male infant delivered at 36 weeks' gestation following an episode of traumatically induced premature labor at 32 weeks. The infant was found to be spastic in flexion with increased stretch reflexes, depressed primitive reflexes, and moderate flexion contractures. Computerized tomographic scans showed bilateral nonenhancing thalamic densities. Neuropathologically, the lateral thalamic nuclei and the red nucleus showed neuron loss, astrocytosis, and, as confirmed by electron microprobe analysis, calcified neurons. The striatum was uninvolved. These findings closely resemble those reported as "symmetrical thalamic degeneration in infancy" and are strongly reminiscent of the pattern of thalamic involvement frequently seen in status marmoratus. It would appear that there is a period during perinatal life in which the lateral thalamus can be rendered vulnerable to hypoxic-ischemic injury, and that the thirty-second week of gestation must be included within this period.

Brain Ischemia↗
PubMed1983

Death from cerebral hypoperfusion during nitroprusside treatment of acute angiotensin-dependent hypertension.

A 37-year-old woman, while being treated with nitroprusside for acute hypertension due to an intramural renal artery hemorrhage, became blind on the fourth hospital day, comatose on the fifth, and brain dead on the seventh. Postmortem examination of her brain revealed border-zone infarcts in the parietal-occipital regions and cerebrellum of the sort associated with cerebral hypoperfusion due to hypotension. Yet her blood pressure had been lowered judiciously to a mean pressure in the vicinity of 110 to 120 mm Hg, and episodes of hypotension had been avoided. As possible explanations for this unusual complication, the roles of acute hyperangiotensinemia and nitroprusside administration are discussed.

Acute Disease↗
PubMed1983

Evolution of pontine and extrapontine myelinolysis.

We report on the serial computed tomographic (CT) changes in the brainstem and cerebral hemispheres of a woman with autopsy-proven pontine and extrapontine myelinolysis who survived for 14 months. The earliest finding was diffuse decreased attenuation values of the gray matter resulting in poor gray-white matter differentiation. Anterior temporal lobe involvement, a finding not previously reported, was demonstrated on CT and confirmed by neuropathologic examination.

Brain↗