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B A Kakulas

Publications and source records attributed to B A Kakulas.

At least 73 records · Page 4Linked to original sources
PubMed1990

Vesicular changes in the myopathies of AIDS. Ultrastructural observations and their relationship to zidovudine treatment.

Six patients with AIDS and AIDS related complex (ARC) who developed neuromuscular symptoms associated with vesicular changes in muscle fibres are reported. Two patients in the advanced stages of AIDS, who did not receive zidovudine, developed proximal limb weakness and wasting: both had a necrotising myopathy with an unusual segmental vesicular change of myofibres. There were numerous vesicles 0.1 to 2 microns in diameter produced by dilatations of the sarcoplasmic reticulum in fibres depleted of myofibrils. Four patients developed a myopathy while receiving zidovudine for AIDS. One of these had an inflammatory myopathy which showed the development of vesicular change due to enlargement and electron lucency of mitochondria. The three other patients with ARC developed muscle pains or weakness and elevated serum CK while on zidovudine. These patients also showed vesicular changes due to enlargement and electron lucency of mitochondria associated with disruption of sarcomeres and the presence of cytoplasmic bodies. The muscular symptoms resolved when ziduvodine was stopped and repeat biopsy in one case revealed no abnormalities.

Acquired Immunodeficiency Syndrome↗
PubMed1989

High-grade cerebral neuroblastoma: a case study.

The case of a 48-year-old male patient is reported in whom a primary malignant cerebral neoplasm was cured by its neurosurgical removal and by postoperative radiotherapy and chemotherapy. Initially, from the results of the examination of frozen and paraffin section, the tumour was considered to be a glioblastoma multiforme. Electronmicroscopy, immunohistochemistry and review of the light microscopy of the original biopsy sample after his death by suicide four-and-a-half years later showed the neoplasm to have been a primary cerebral neuroblastoma rather than a glioblastoma. The diagnosis of glioblastoma multiforme, which depends upon multiple non-specific microscopic findings, such as necrosis, abnormal blood vessels, anaplasia and the pleomorphism of tumour cells, often is imprecise. Our experience underlines the need for comprehensive neuropathological studies of malignant cerebral neoplasms, including transmission electronmicroscopy and immunohistochemistry. This is of particular importance in view of the dismal prognosis of glioblastoma multiforme and of the palliative, rather than curative, treatment programmes that frequently are indicated for this tumour. The value of our report is to demonstrate that a cerebral neuroblastoma, which potentially is curable, may be mistaken easily for a glioblastoma-even by competent neuropathologists.

Brain Neoplasms↗
PubMed1989

Burst fractures in the thoracic and lumbar spine. A clinico-neuropathologic analysis.

Neuropathologic analysis of eight acute and 12 chronic burst fractures was performed. In the acute cases, the injury to the bony, ligamentous, and neural tissues was investigated. Serious Denis B or D fractures showed signs of pronounced instability, and all had a large bone fragment rotated into the spinal canal. The neural tissues were compressed in two cases and transected in one. The Denis A fractures had relatively well-restored ligamentous structures and the bone fragment in the spinal canal was narrowing the spinal canal less than 50% in all cases. Three of four had normal neural tissue macroscopically and microscopically. The majority of the patients with chronic burst fractures did not show any sign of bone fragment resorption. Six out of eight patients with thoracolumbar (T12 and L1) and lumbar (L3) fractures experienced intractable burning pain and/or rhizopathy. The pain seemed to be caused by entrapment of the nerve roots in adhesions.

Acute Disease↗
PubMed1989

Deposition of Alzheimer's disease amyloid (A4) protein in the cerebral cortex in Parkinson's disease.

The prevalence of deposition of the Alzheimer's disease A4 amyloid protein in representative areas of the cerebral cortex was compared using a sensitive immunohistochemical technique in a group of 26 cases of idiopathic Parkinson's disease (PD) and in a control group of 82 subjects of comparable age who had died unexpectedly from non-cerebral causes. Cortical A4 protein deposition was found in 54% of PD subjects and 48% of the control group, while deposition of A4 protein in meningeal or cortical blood vessels was found in 38% of PD subjects and 25% of controls. When allowance was made for age and sex, the differences between the two groups were not found to be statistically significant. Heavy cortical A4 protein deposition was found in a number of PD cases, including two of four cases with dementia, and was absent in the other two cases. The present findings indicate that a large proportion of cases of idiopathic PD have associated Alzheimer's disease changes. In some cases these lesions are of sufficient severity to account for dementia. In other cases the changes are less severe and are probably subclinical but may be a contributory factor to the development of cognitive impairment and dementia. The absence of Alzheimer changes in some demented PD cases indicates that the dementia of PD is heterogeneous.

Aged↗
PubMed1988

An investigation of possible transynaptic neuronal degeneration in human spinal cord injury.

Neurophysiological studies suggested that transynaptic neuronal degeneration of the anterior horn cells (AHC) may occur after an upper motoneuron lesion as the result of "deafferentation". To test this observation anatomically, patients with spinal cord injury (SCI) who had come to post mortem were investigated. Four patients with longstanding clinically and pathologically "complete" SCI were selected for comparison with 4 age-matched normal controls and with 2 patients who died of motoneuron disease (MND). The total number of AHCs in the L3 spinal cord segment was counted in each of the cases. The lesions in the traumatic group were all above the L3 segment. No significant differences in the number of AHC between the test cases and the normal controls was found. There was, as expected, a highly significant difference between the test cases and those with MND. The conclusion drawn from the study is that transynaptic neuronal degeneration of AHCs does not occur following complete transection of the human spinal cord. Thus the neurophysiological hypothesis is not supported anatomically.

Humans↗
PubMed1988

Myopathies associated with hypothyroidism: a review based upon 13 cases.

The clinical and myopathological features of 13 patients with a myopathy occurring in association with hypothyroidism are presented. Seven patients had hypothyroid myopathy, including two with the Hoffmann syndrome and one with the Kocher-Debre-Semelaigne syndrome. Five patients had an inflammatory myopathy and one had polymyalgia rheumatica. Serum CK activity was elevated up to 12-fold in the patients with hypothyroid myopathy and returned to normal after treatment with thyroxine. Pathological changes in these cases included type 1 or type 2 fibre atrophy or hypertrophy, myofibre necrosis and regeneration in four cases and, in one case, prominent core-like areas containing amorphous granulo-filamentous material. The findings in this series of cases illustrate the clinical and histopathological heterogeneity of patients with hypothyroid myopathy and the need to consider other myopathies in hypothyroid patients who present with muscular symptoms.

Adolescent↗
PubMed1988

Observations on the pathogenesis of Duchenne muscular dystrophy in the light of recent progress in molecular genetics.

The gene on the X chromosome which, when abnormal, causes Duchenne muscular dystrophy (DMD) is estimated to be at least 1800 kb in length, making it possibly the largest in the entire human genome. Cloned mRNA derived from the gene indicates that it codes for a protein with a molecular weight of approximately 400,000 daltons. This protein, which is expressed in very low concentration (one molecule to each of 15 muscle nuclei), has been named dystrophin. It is anticipated that the molecular biology of dystrophin will now be elucidated quickly so that its function in the cell is revealed and steps to correct the biochemical defect initiated. It is also possible that the gene codes for a family of proteins and that these reside within the intermediate filament system of the cytoskeleton. Candidate proteins are spectrin, nebulin and titin, as well as dystrophin. In the light of these advances in the molecular genetics of DMD, it is timely for the myopathologist to suggest possible mechanisms of aetiopathogenesis for the disorder. In this regard the first unequivocal lesion in muscle biopsies in DMD is focal muscle fibre necrosis. Electron microscopy (EM) reveals excessive hypercontraction of sarcomeres, especially in the early stages. These hypercontracted zones correspond to the 'hyalinized' muscle fibres typical of the disorder. It seems possible that such hypercontractions cause tears in the plasma membrane of the muscle fibre which may be weakened by an abnormality of the intermediate filaments which underlie the lipid bilayer.(ABSTRACT TRUNCATED AT 250 WORDS)

Cloning, Molecular↗
PubMed1987

The clinical neuropathology of spinal cord injury. A guide to the future.

The neuropathology of spinal cord injury (SCI) is reviewed in the light of clinical problems and as a guide to future research. The pathology of SCI in the acute stage suggests that the spinal cord may be partly preserved even in the most severe injuries. This finding emphasises the need for great care in roadside management. In the acute phase there are irreversible changes and possibly reversible changes which have not been adequately identified. Even a small percentage of nerve fibres escaping the initial injury would be of great benefit to the patient. In the subacute stage when transynaptic degeneration is proceeding there may also be associated functional changes leading to abnormal reflex activity. It is possible through an improved understanding of the neuropathology and neurophysiology of the isolated or partly isolated segments of the cord that new reflex connections may be stimulated to develop by artificial means. In the chronic stage there are well recognised complications such as osteoarthrosis with spinal stenosis, post-traumatic syringomyelia and traumatic nerve root neuroma formation, which may lead to clinical deterioration and which may be amenable to treatment. In a more theoretical sense it is possible that improved understanding of CNS plasticity and transplant neurobiology using recombinant DNA technology, grafting and 're-education' of the regenerated tissues may be rewarding in the longterm future. Although this outcome is entirely hypothetical at this stage basic research deserves great emphasis.

Forecasting↗
PubMed1987

Cerebral gliomas with palisading necrosis: glioblastoma multiforme or high grade cerebral neuroblastoma? A light and electron microscopical study of three cases.

Three adult patients had cerebral malignant gliomas composed predominantly of small cells and displaying many areas of palisading necrosis, which are usually characteristic of glioblastoma multiforme. Light and electron microscopy, however, revealed tumour cells with neuritic processes, while astrocytic differentiation was convincingly excluded. It is suggested that palisading necrosis is not pathognomonic of glioblastoma multiforme and that high grade cerebral neuroblastoma should be considered in the differential diagnosis. The need for comprehensive light and electron microscopic studies for the accurate classification of gliomas is stressed.

Aged↗
PubMed1987

Unusual paraspinal muscle lesions in ankylosing spondylitis.

Minicore, multicore, core-targetoid and other ultrastructural lesions were found in the paraspinal muscles of patients with AS. The 10 patients studied, all men with AS, showed varying degrees of muscle fibre atrophy, Z band streaming, rod body formation, minicores, multicores and core-targetoid fibres. Central core disease, rod body myopathy, minicore and multicore diseases are recognized clinical entities within the congenital group of structural myopathies. Target fibres are believed to be a feature of reinnervation. It is also known that experimental tenotomy causes core-targetoid changes, rod bodies, minicores and multicores. Therefore, it seems possible that tension is a necessary stimulus for the correct programming of synthetic muscle enzymes, and without this disorganization occurs. It may also be assumed, but in this case for genetic reasons, that similar biochemical systems are disturbed in the group of congenital myopathies.

Adult↗
PubMed1986

Causes of organic dementia: a necropsy survey of 60 cases.

The neuropathological findings in all demented patients who were necropsied at the Sir Charles Gairdner Hospital during a 10-year period were reviewed. Of a total of 60 cases, 44 (73.3%) had the typical changes of Alzheimer's disease, while a variety of other conditions accounted for the remaining 16 cases--neoplasms (four patients); lacunar disease (four patients); viral infections (three patients: herpes simplex in two and Creutzfeldt-Jakob disease in one); non-specific brain atrophy (two patients); and single cases of Huntington's chorea, subdural haematomas and methotrexate-induced leucoencephalopathy. Associated cerebral pathologies were found in 17 (38.6%) of the cases of Alzheimer's disease and included vascular lesions (eight cases), subdural haematomas (six cases) and Wernicke's encephalopathy (two cases).

Aged↗
PubMed1986

The effect of the myotoxic agent iodoacetate on dystrophic mice 129/Re.

Three groups of dystrophic and non-dystrophic mice 129/Re were used for studying the effect of the myotoxic agent iodoacetate on dystrophic muscle. The mice of the first group were given intramuscular injections of iodoacetate. The mice of the second group were injected with normal saline and the third group was maintained as untreated controls. The most severe histopathological changes were found in the dystrophic mice treated with iodoacetate. The non-dystrophic mice of the same group showed a significant increase in the number of internal nuclei. Moderate changes were observed in saline-treated dystrophic controls. There was no significant decrease in the life expectancy in any of the groups. The body weight of dystrophic mice was reduced throughout the experiment. On the contrary the non-dystrophic group showed an increased in weight, regardless of the treatment. The aggravation of the histopathological changes of dystrophic mice by iodoacetate would probably give support to the cyclical necrosis/abnormal regeneration theory of pathogenesis of muscular dystrophy.

Animals↗
PubMed1986

Ovine congenital progressive muscular dystrophy: clinical syndrome and distribution of lesions.

The distribution and severity of lesions in the skeletal muscles of 37 Merino sheep with congenital progressive muscular dystrophy (CPMD) are described. An explanation for the clinical signs is offered on the basis of functional defects in regional muscle groups. Lesions in the extensors of the hip, stifle and hock joints and flexors of the digits are primarily responsible for the progressive abnormality of hind limb gait that is characteristic of the clinical syndrome. Lesions in extensors of the elbow and flexors of the shoulder, carpus and digits affected fore limb function in advanced cases. The tendency for some affected sheep to develop ruminal tympany is probably caused by lesions in the diaphragmatic crus. Clinically affected sheep had higher resting and post-exercise concentrations of serum creatine phosphokinase and lactic dehydrogenase than unaffected control sheep. The rise in serum creatine phosphokinase after exercise was greater in affected sheep than in controls. Myotonia was not demonstrated in electromyographic studies in one sheep.

Animals↗
PubMed1986

Central neural antigens: detection and diagnostic application.

During the last few years, methods have been developed which permit practical use of biochemical research on the nervous system. In the central nervous system, proteins have been identified for astrocytes (glial fibrillary acidic protein and vimentin) and oligodendroglia (myelin basic protein and other glycoproteins). For certain classes of nerve cells, the neurofilament proteins and neuron-specific enolase (a glycolytic isoenzyme) have been identified. Detection of some of these substances in body fluids is possible via radioimmunoassays (RIA) and in tissue sections using the peroxidase-antiperoxidase immunohistochemical method.

Animals↗
PubMed1986

The neuropathology of progressive autonomic failure of central origin (the Shy-Drager syndrome).

The neuropathological features of the "Shy-Drager syndrome" have, in the past, been unsettled. The position was recently clarified by Oppenheimer who reviewed the 51 reported patients with progressive autonomic failure in whom neuropathological findings were given. He divided these cases into two groups. Group I included those with lesions of the pigmented nuclei of the brain stem which contained Lewy bodies. These he further subdivided into subgroups IA or IB according to whether or not the patient showed clinical evidence of Parkinson's disease in addition to the common denominator of orthostatic hypotension. In group II he placed those patients in whom multiple system atrophy was found at necropsy. These were the majority. Loss of neurons from the intermediolateral columns of the thoracic spinal cord, thought to be the cause of the postural hypotension, was present in all cases. To illustrate the new classification the necropsy findings in 3 patients taken from the files of the Royal Perth Hospital are described. One of these showed the lesions of Parkinson's disease with Lewy bodies, and thus conformed to Oppenheimer's type IA. The two other patients showed multiple system atrophy and thus belonged to Oppenheimer's type II. All three showed loss of neurons in the intermediolateral columns of the thoracic spinal cord. We believe that Oppenheimer's classification of progressive orthostatic hypotension improves the clinicopathological understanding of the syndrome and is thus useful as well as informative to the practising neurologist.

Aged↗
PubMed1986

Observations on the clinical presentations and the neuropathological findings of amyotrophic lateral sclerosis in Australia and Guam.

Among 20 consecutive autopsies of amyotrophic lateral sclerosis (ALS) occurring in Caucasians in Western Australia (WA), 85% were males. The median age of onset was 58.9 years and the average duration of illness was 2.4 years. Twenty-two randomly selected ALS occurring among natives in Guam also showed a male predominance of 75%, younger age of onset (median 48.5 years) and longer survival period (median 3.4 years). 45% of the WA patients presented with bulbar involvement at the time of first examination. These patients had the lowest median survival period of 1.5 years when compared with the other forms of ALS, the classic upper and lower motor system involvement and progressive muscular atrophy. Theneuropathologic lesions of ALS in WA and Guam were similar with the exception that neurofibrillary tangles were frequently present in the Guamanian brains. In 14%, neuronal loss, gliosis and frequency of tangles in the cerebral cortex especially in Ammon's horn, substantia nigra, and locus ceruleus, were sufficiently severe to indicate the coexistence of another disorder, Parkinsonism-Dementia Complex. This condition was not clinically recognized. In the WA cases only one patient had tangles in the brain and he had concurrent Alzheimers disease. While senile plaques were present in this patient they were usually absent in the Guamanian brains.

Adolescent↗
PubMed1985

Medulloblastoma: a clinicopathological study of 42 cases.

Clinicopathological data have been collected for 42 patients with cerebellar medulloblastoma diagnosed and treated in Western Australia between the years 1961 and 1984. Thirty-one patients were male and 12 were over 14 years of age. In 31 patients the neoplasms were localized to the midline, while in 10 they were placed laterally in the cerebellar hemispheres. The remaining patient had a diffusely spreading neoplasm in the meninges of the posterior fossa. Thirty-nine underwent surgical treatment followed by postoperative radiotherapy. Three patients died in the early postoperative period. Twenty-four patients survived for one year or longer, 15 for two or more years, 10 for five years, and five survived longer than 10 years. The survival proportions estimated by the life-table method were 66% at one year, 48% at two years and 32% at 5 and 10 years. In one patient who survived for 23 years a meningioma developed, possibly due to radiotherapy.

Adolescent↗