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S Naidu

Publications and source records attributed to S Naidu.

At least 109 records · Page 6Linked to original sources
PubMed1988

Childhood adrenoleukodystrophy. Failure of intensive immunosuppression to arrest neurologic progression.

Cyclophosphamide in a dosage of 350 to 700 mg/m2/d was administered for five to 11 days to four patients with childhood adrenoleukodystrophy (ALD) and to one patient with the adult cerebral form of the disease. The rate of neurologic progression in the four patients with childhood ALD did not differ from that of 167 untreated patients with childhood ALD surveyed previously.

Adrenoleukodystrophy↗
PubMed1988

Selenium treatment in neuronal ceroid-lipofuscinosis.

Neuronal ceroid-lipofuscinosis (NCL) refers to a group of disorders with devastating effects on the central nervous system. The accumulation of autofluorescent lipopigments containing lipid peroxides is considered a pathogenetic mechanism of the cell damage seen in NCL. Therapy aimed at preventing further lipid peroxidation, such as the Zeman regimen, did not slow progression of the disease. Therefore, Santavuori and Westermarck [Santavuori and Westermarck 1984] introduced treatment with a combination of selenium and vitamin E and reported favorable results with few side effects. We present information on the rationale for the use of selenium, recommendations on the daily intake, and reported side effects. However, our limited experience with selenium in this disorder does not permit conclusions. Additionally, careful studies are indicated before this treatment is dispensed routinely.

Child↗
PubMed1988

Galactosylceramide-beta-galactosidase deficiency in association with cherry red spot.

A 13-month-old white girl was the product of a normal pregnancy and delivered by caesarean section for breech presentation. Regression of motor milestones started by 11 months, when delayed language development was also noted. She was normocephalic without major dysmorphic features or organomegaly. Fundus examination disclosed a subtle cherry red spot bilaterally. No startle response was elicited. By 17 months she was extremely irritable and unable to tolerate liquids; there was symmetrical spasticity and florid cherry red spots. She died at 18 months of age. A systematic search for conditions associated with a cherry red spot was unrevealing. The absence of galactosylceramide galactosidase activity was unexpected and was confirmed on three occasions in two laboratories. Lactosylceramide I content, an enzyme thought to be identical to galactosylceramide-beta-galactosidase, was significantly decreased. The presence of a cherry red spot in Krabbe's disease, indicative of neuronal storage, has not been previously recognized. The existence of this variant has implications for genetic and biochemical studies.

Brain↗
PubMed1988

Auditory brainstem response and audiologic findings in adrenoleukodystrophy: its variant and carrier.

Auditory brain stem response, auditory sensitivity, speech discrimination function, acoustic reflex threshold, and reflex decay were studied in seven children with adrenoleukodystrophy (ALD), nine adults with adrenomyeloneuropathy (AMN), one child with neonatal ALD, and two carriers of ALD. Significant auditory dysfunctions were found in only two patients; a retrocochlear type auditory disorder in one child with ALD, and a profound deafness in a child with neonatal ALD. None of the patients showed significant abnormality in acoustic reflex threshold and reflex decay except for one patient with ALD who showed a slightly elevated reflex threshold. All but two ALD patients showed significantly prolonged wave latencies and interwave intervals. The latency values revealed the highest incidence of abnormality in the I to III interval; this was followed by the III to V interval, then by wave I. Significantly, one child with asymptomatic ALD and both heterozygous female relatives showed abnormal ABRs, demonstrating the high sensitivity of ABR in detection of the existence of pathophysiological condition in subclinical or presymptomatic ALD.

Adolescent↗
PubMed1988

The clinical recognition and differential diagnosis of Rett syndrome.

Rett syndrome (RS) is characterized by progressive loss of intellectual functioning and fine and gross motor skills as well as development of stereotypic hand movement abnormalities, occurring after 6 to 18 months of normal development. Rett syndrome has been previously reported only in girls, but the possibility of the syndrome existing in male children cannot be currently excluded. Although the syndrome is thought to be relatively common, it was only described in the English literature 5 years ago. There is currently no marker for the syndrome; diagnosis is based on clinical criteria. The newly developed diagnostic criteria for RS are reviewed, with special attention given to the historical aspects of the diagnosis in the prenatal, perinatal, neonatal, and early childhood periods. Rett syndrome is characterized by a predictable, orderly progression of signs and symptoms. Four stages of RS have been described; each stage has special characteristics and offers different diagnostic challenges for the neurologist. Infantile autism is the most common incorrect diagnosis made for children with RS. The simultaneous regression of both motor and language skills, as well as the stereotypic hand movements, hyperventilation, bruxism, and seizures in early childhood are all typical in RS and help distinguish RS from infantile autism.

Ammonia↗
PubMed1988

Research on Rett syndrome: strategy and preliminary results.

The research strategy presented here involves four assumptions: (1) Rett syndrome exists; (2) a single cause will eventually be found to account for the majority of cases presently assigned to this disease category; (3) it is genetically determined; and (4) it represents a neurodegenerative disorder that can be defined by quantitative studies of nervous system structure and function. The strategy proposed here involves the comprehensive study of 100 patients with the classic Rett syndrome phenotype. Studies include the (1) search for a diagnostic marker; (2) high-resolution cytogenetic banding techniques, (3) quantitative morphologic studies of postmortem brain tissue as well as neurochemical analyses including autoradiographic techniques, radioimmunoassays, and in situ hybridization; and (4) positron emission tomography studies of cerebral glucose metabolism and neurotransmitters.

Adolescent↗
PubMed1988

Recommendations regarding handling of the necropsy in Rett syndrome.

In order to maximize biochemical, neurochemical, molecular, and pathologic information from patients with Rett syndrome, a uniform procedure has been developed for the conduct of the postmortem examination. Tissue should be prepared for freezing, for electron microscopy studies, and for standard histologic examination. For the purposes of uniformity, three central repositories for necropsy materials have been established and are available at all times. In the event of the death of a patient with Rett syndrome, parents who consent to necropsy should request that materials be handled according to the protocol and transported under appropriate conditions to the central repository. The National Neurological Research Bank (Los Angeles), the Brain Tissue Bank (Belmont, Mass), and the Department of Neuropathology at Johns Hopkins Hospital (Baltimore) have agreed to serve as repositories for tissues. A committee of the International Rett Syndrome Association medical advisory panel will monitor this process in cooperation with the directors of the respective tissue banks.

Ammonia↗
PubMed1988

Neonatal seizures and retardation in a girl with biochemical features of X-linked adrenoleukodystrophy: a possible new peroxisomal disease entity.

Neonatal hypotonia, seizures beginning at 5 days, and severe retardation were noted in a girl with normal karyotype and biochemical evidence of impaired adrenal function. Postmortem examination at 14 months revealed malformative and destructive lesions of central gray and white matter, atrophy of adrenal cortex with striated adrenocortical cells, hepatic fibrosis, and PAS-positive macrophages in several organs. Pathologically and clinically, this patient most closely approximated neonatal adrenoleukodystrophy (ALD) and differed strikingly from X-linked childhood ALD. In contrast, biochemical changes resembled the abnormalities observed in X-linked ALD and differed from those in the neonatal form. The very-long-chain fatty acid accumulation characteristic of both disorders was demonstrated, but unlike neonatal ALD, the levels or metabolism of plasmalogens, pipecolic acid, phytanic acid, and bile acid intermediates were normal, and peroxisomes in a liver biopsy specimen were present in normal number and appeared enlarged. While the case resembles the recently reported entity of peroxisomal acyl-CoA oxidase deficiency, assignment to this category was excluded by immunoblot studies on postmortem liver, which revealed normal amounts of this enzyme. Correlation of clinical, morphologic, and biochemical data suggests that this case is an example of a so-far undescribed entity, and reinforces the concept that the phenotypic spectrum of peroxisomal disorders is wider than realized.

Adrenoleukodystrophy↗
PubMed1988

Production of toxic shock syndrome toxin-1 (TSST-1) associated with Staphylococcus aureus from a pyogenic skin infection.

Toxic Shock Syndrome Toxin-1 (TSST-1) producing Staphylococcus aureus associated with TSS was isolated from an abscess on buttock, from a two-year-old male child suffering from diarrhoea, high fever and shock. The isolate was subclassified into S. aureus var. hominis of CV type-D, and was lysed by phage 75 of Group-III. It was multidrug resistant, exhibited double ring (DR) CVRT pattern and also produced enterotoxin-C (SE-C). Out of 217 S. aureus strains from pyodermas, clinical sources, food poisonings and dairy foods, 139 (64.1%) produced enterotoxin. SE-C as single (33.8%) or in combinations (25.2%) was common enterotoxin. None of these strains produced TSST-1.

Abscess↗
PubMed1987

A new dietary therapy for adrenoleukodystrophy: biochemical and preliminary clinical results in 36 patients.

A new dietary regimen has been administered for periods ranging from 60 days to 1 1/2 years in 34 patients with various forms of X-linked adrenoleukodystrophy (ALD), as well as in 1 patient with neonatal ALD and 1 patient with infantile Refsum's disease. The diet combines the administration of a glyceryl trioleate oil (GTO) with the dietary restriction of very-long-chain fatty acids (VLFA), particularly hexacosanoic acid (C26:0). Reductions in the levels of plasma C26:0 and other VLFA were achieved in 25 of the 36 patients. Fifteen of these 25 patients were treated for more than 100 days. The mean reduction of the plasma C26:0 level was 53% (range, 22 to 73%) in these 15 patients. While the focus of the study was on biochemical variables, comparison of pre- and post-diet studies of peripheral nerve function showed improvement in 1 patient with adrenomyeloneuropathy (AMN) and 1 heterozygote. In contrast, 2 patients with ALD onset in childhood developed new neurological deficits while on therapy. We conclude that it is possible to lower plasma VLFA levels in ALD patients. A clinical trial is indicated to test whether this approach can alter the neurological progression in patients with AMN or in symptomatic heterozygotes, and to determine whether it can prevent the onset of neurological disability in asymptomatic persons who have the biochemical defect of ALD.

Adrenoleukodystrophy↗
PubMed1987

Adrenoleukodystrophy: biochemical procedures in diagnosis, prevention and treatment.

The childhood form of adrenoleukodystrophy is an X-linked recessive disorder which is characterized biochemically by elevated concentrations of saturated very long chain fatty acids in tissues and plasma and impaired very long chain fatty acid oxidation in fibroblasts and leukocytes from adrenoleukodystrophy patients. The most consistently observed increase is that in hexacosanoic acid (C26:0); thus, measurement of plasma C26:0 concentration by gas-liquid chromatography provides a rapid, sensitive method of diagnosis. Prenatal diagnosis of adrenoleukodystrophy can be made by measurement of C26:0 concentrations in amniocytes and chorionic villus cells. Heterozygote (carrier) detection has also been accomplished by biochemical measurement of C26:0 in plasma and skin fibroblasts. In a study of over 200 obligate heterozygotes, greater than 90% showed abnormal concentrations of C26:0. Hybridization studies using the cloned DNA fragment St14 detects polymorphisms in the distal end of the long arm of the X chromosome (Xq27-28) and six informative kindreds have shown co-segregation of adrenoleukodystrophy and the St14 marker through 65 meioses. Thus, such studies can supplement very long chain fatty acid concentrations in heterozygote detection. Therapeutic interventions for adrenoleukodystrophy, such as dietary restriction of very long chain fatty acids, administration of clofibrate or carnitine, immunosuppression and adrenal hormone replacement, have not been successful. Recently, a modification of the very long chain fatty acid-restricted diet has been employed in which this diet is supplemented with synthetic glycerol trioleate. The rationale for this diet is that decreased very long chain fatty acid synthesis by fibroblasts from patients with adrenoleukodystrophy was observed when oleic acid was added to the culture medium.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenoleukodystrophy↗
PubMed1987

A set of monozygotic twins with Rett syndrome.

The case history of a set of twins with Rett syndrome is presented. The twins test as monozygotic by both blood groups and HLA titers. In a previous generation, the family had three females who died of an unknown degenerative disease on the paternal side of this family. The discussion includes a hypothesis about female genetic disease occurring in a recessive pattern on the X chromosome.

Brain Diseases↗
PubMed1987

Rett syndrome: new observations.

Two elderly females with Rett syndrome are reported with evidence of a slowly progressive central and distal peripheral nervous system involvement. Thermography in 4 girls confirmed distal hypothermia of the extremities in a glove and stocking distribution. Unilateral sympathectomy during surgery for scoliosis in one of them resulted in increased warmth and physical growth of the foot and nails, compared to the uninjured side. This suggests increased sympathetic tone as the probable cause of distal hypothermia, vasomotor instability and dystrophy of the feet in this disorder. In an attempt to identify a marker, girls with clinically classical Rett syndrome had plasma and urinary cell evaluation for an unusual glycolipid. A blind study using a small number of patients failed to prove absolute specificity and additional studies are required to evaluate its validity as a marker for Rett syndrome.

Adult↗
PubMed1987

Adrenoleukodystrophy: correlating MR imaging with CT.

The effect on the brain of the sex-linked recessive form of adrenoleukodystrophy was studied in 40 boys, 4-18 years old. All underwent computed tomography (CT) scanning; six underwent magnetic resonance (MR) imaging. MR showed a high sensitivity in demonstrating white matter disease. Auditory pathway disease was characterized as involvement of the lateral lemniscus and medial geniculate body, and visual pathway disease was characterized by lateral geniculate body, Meyer loop, and optic radiation involvement. Contrast-enhanced CT still proved to have a greater capacity (at this time) to show the active, advancing form of the disease and concomitant calcifications. This large CT series also demonstrated the broad and variable expressions of adrenoleukodystrophy, which allowed the unification of previously described atypical forms of the disease.

Adolescent↗
PubMed1987

The adrenoleukodystrophies.

Clinical, biochemical, and genetic studies of adrenoleukodystrophy (ALD) are of current interest for six main reasons. First, assays of plasma lipids or cultured skin fibroblasts or amniocytes permit precise diagnosis of persons affected by the disease, as well as prenatal diagnosis and carrier detection. Second, the general nature of the enzymatic defect has been identified and the ALD gene has been mapped to the q28 segment of the X-chromosome. Third, the disease is more common than had been previously recognized. We have identified 350 patients in over 200 kindreds. Fourth, phenotypic variability is a striking feature. The illness may present as a rapidly fatal neurological disorder in early childhood or as a chronic progressive paraparesis in young, middle-aged, or even older adults. The latter syndrome is referred to as adrenomyeloneuropathy (AMN). It is of particular interest that these variants occur regularly within the same kindred, so that the phenotypic variation cannot be attributed to different genetic mutations. A fifth feature of interest is that in this X-linked disorder 12 to 40% of female carriers show various degrees of neurological disability, although almost always milder than in the hemizygous male. Studies with cultured fibroblasts suggest that mutant ALD cell lines have a competitive advantage over normal cell lines, a phenomenon which has not been observed in any other disorder. Finally, ALD appears to be one example of a peroxisomal disorder. Knowledge about the normal function of this subcellular organelle has emerged only recently, and further studies of ALD and related disorders will contribute to this.

Adrenoleukodystrophy↗
PubMed1986

Rett syndrome--natural history in 70 cases.

We evaluated, at our institute, 70 females with Rett syndrome between 2 1/2 to 34 1/2 years old. This provided an opportunity of observing the natural history of this condition. The evolution of a subacute encephalopathy of very early onset, maximizing in the second year of life, with slow recovery and devastating sequelae, was recognized. The hyperorality, visual auditory and tactile agnosia with aphasia and seizures resembled symptoms described in human Kluver Bucy syndrome. Over interpretation of behavioral abnormalities as seizures was common. Scoliosis was not a necessary concomitant of age. A consistent biochemical or neurophysiological abnormality was not detectable in understanding the cause and pathogenesis of this disease process. Life span appears to be unaffected though life tables have not yet been established.

Adolescent↗