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PubMed1987

Long-term prognosis of tuberous sclerosis with epilepsy in children.

A follow-up study was performed on 40 children with tuberous sclerosis and epilepsy. In 68% of the patients with infantile spasms and 73% of those without them, complex partial seizures were observed. Thus, patients with tuberous sclerosis are subject to not only infantile spasms but also complex partial seizures. Patients with infantile spasms showed mental retardation more often than those without. Seizures which had evolved from infantile spasms were more difficult to control than those which had not. The prognosis of infantile spasms associated with tuberous sclerosis was better than that of prenatal group other than tuberous sclerosis. Forty percent of the 40 cases showed asymmetry on EEG, and the asymmetry tended to disappear as the patients grew up.

Adolescent↗
PubMed1998

Magnetic source imaging and reactivity to rhythmical stimulation in tuberous sclerosis.

The present study combined functional magnetoencephalography (MEG) and anatomical magnetic resonance imaging (MRI) information in three patients affected by tuberous sclerosis and partial epilepsy. MEG recordings were performed during both spontaneous and visual evoked activity. The former showed a large variety of complexes whose spatial and temporal distribution suggested different neuronal populations acting simultaneously in the same focal district. When these data were integrated with MRI images (magnetic source imaging, MSI) there was agreement in the definition of tubers and extension of the epileptogenic area. Furthermore, cortical reactivity to rhythmical stimulation was studied with trains of visual stimuli according to a recently proposed frequency responsiveness procedure (FRP). As compared to normal controls, a large 6 Hz activity was observed during the pause after a non-resonant stimulation. This altered resonance property may indicate a disturbed primary sensory processing notwithstanding a preserved associated processing. These results show that neuronal malfunctioning in tuberous sclerosis complex patients may not be restricted to the area of cortical tubers, but can also affect functionally correlated regions.

Adolescent↗
PubMed2000

West syndrome in tuberous sclerosis complex.

West syndrome occurs commonly in children with tuberous sclerosis complex and is associated with a grave prognosis for cognitive and seizure outcomes. We sought to determine the epilepsy outcome of children with tuberous sclerosis complex and West syndrome and whether EEG, MRI, or steroid therapy duration were different in those whose epilepsy improved compared with those with intractable seizures. Seventeen patients with tuberous sclerosis complex and West syndrome were identified. For each patient, two sets of clinical evaluations, EEG and MRI data, and treatment information separated by at least 12 months were obtained. The patients were divided into two seizure outcome groups. EEG, MRI, and treatment data were compared between the groups. The intellectual deficiency was either severe (76%) or moderate (24%). Seizure control improved in 10 and worsened in seven, without mortality (follow-up range = 12-216 months). No significant differences in EEG background, MRI findings, or steroid treatment duration were evident between the groups. The difference in EEG-sleep approached statistical significance (P = 0.06). Our findings did not confirm reports of high mortality and poor epilepsy outcome in intellectually deficient children with West syndrome and tuberous sclerosis complex. EEG sleep was the best indicator of seizure control and approached statistical significance. The duration of steroid therapy had no influence on seizure control.

Adolescent↗
PubMed1997

Evidence of abnormal differentiation in giant cells of tuberous sclerosis.

To characterize the giant cells in tuberous sclerosis, we examined immunoreactivity for nestin, vimentin, microtubule-associated protein 1B (MAP1B), MAP2, neurofilament, and glial fibrillary acidic protein (GFAP) in cortical tubers detected in brain specimens from 6 patients with tuberous sclerosis who had undergone surgical resection for treatment of intractable epilepsy. Giant cells with a neuronal appearance, "neuron-like giant cells," had a round centrally-placed nucleus with a single, prominent nucleolus, and Nissl substance was commonly present in cortex. These neuron-like giant cells demonstrated consistently strong immunoreactivity for neurofilament and MAP1B and occasional immunopositivity for nestin and vimentin and were rarely positive for GFAP. "Indeterminate giant cells," characterized by abundant cytoplasm, an absence of Nissl substance, and one or more eccentric nuclei, demonstrated consistent immunoreactivity for nestin, vimentin, and MAP1B and were rarely positive for neurofilament, but more than half displayed immunoreactivity for GFAP. These observations suggest that the indeterminate giant cells exhibit limited neuronal and inconsistent astroglial characteristics, implying aberrant cellular differentiation in tuberous sclerosis.

Cell Differentiation↗
PubMed1997

[Bourneville's tuberous sclerosis and autism].

Tuberous sclerosis is often associated with developmental and behavioural disorders including typical or partial autistic syndrome. However, it may be difficult to recognize tuberous sclerosis behind an infantile autism during the early stages of the disease. Therefore, tuberous sclerosis must be regularly looked for on the basis of its major and minor criteria in any cases of infantile autism. The child psychiatrist is preferentially involved in the management of the various aspects of this association, ie, behavioural or character disorders, difficulties in social relationships and communication, mental retardation, feeding disorders, and psychological consequences for the families. The support provided may be complemented by that offered by the Association for Bourneville's tuberous sclerosis.

Autistic Disorder↗
PubMed2005

Application of bubble separation for quantitative analysis of choline in Dioscorea (yam) tubers.

A modified assay based on the AACC official method 86-45 (AACC, 2000) for the determination of choline in three cereals and three varieties of Dioscorea (yam) tubers was developed. When tested in wheat, rice, and oat flour, choline estimated by the modified method was 34.0-45.3% higher than that of the original AACC method. In a system with higher contents of starch and mucilage, such as Dioscorea (yam) tubers, extra procedures in sample preparation needed to be carried out to separate starch and mucilage. The choline contents of the following Dioscorea (yam) tubers using the original AACC method and the present modified AACC method through coupling an additional bubble separation procedure, respectively, were (mean +/- SD, mg/g solid) Keelung yam (D. pseudojaponicaY.) 0.92 +/- 0.09 and 2.21 +/- 0.12, Yangmingshan yam (D. alata L.) 0.77 +/- 0.09 and 1.78 +/- 0.28, and Ming-Chien yam (D. purpurea) 0.44 +/- 0.09 and 1.35 +/- 0.19. Choline was 231-306% higher than when the original AACC method was used. Dioscorea (yam) tubers were much higher in choline content than they were in cereals. Bubble separation is an appropriate procedure in the practice for the maximum assay of choline in yams. It is accurate, rapid, easy to handle, and especially good for recovering choline from a starch and polysaccharide-protein-containing system.

Adhesives↗
PubMed2001

Renal angiomyolipoma associated with micronodular pneumocyte hyperplasia of the lung with tuberous sclerosis.

Tuberous sclerosis complex is an autosomal-dominant disorder characterized by the triad of mental retardation, epilepsy and adenoma sebaceum. Micronodular pneumocyte hyperplasia is a rare but distinctive pulmonary epithelial lesion, usually associated with tuberous sclerosis. To the authors' knowledge, the relationship between renal angiomyolipoma and micronodular pneumocyte hyperplasia in cases of tuberous sclerosis has not received attention in the urological literature. The case of a woman with renal angiomyolipomas associated with micronodular pneumocyte hyperplasia of the lung with tuberous sclerosis is reported here.

Adult↗
PubMed2002

Epilepsy surgery outcome in children with focal epilepsy due to tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is frequently associated with focal epilepsy due to cerebral tubers. Seizures are the first symptoms in most patients with brain involvement. These epilepsies are frequently severe, drug-resistant and may have a negative impact on the child's global development. Although most epilepsies are multicentric, these patients may be candidates for epilepsy surgery, if it is possible to determine a leading epileptogenic tuber. Nine patients with TSC were examined with long-term video-EEG monitoring, different neuroimaging techniques and neuropsychological tests. A main epileptogenic tuber could be identified in all of our patients. We found good correlations between neuroimaging and EEG. Surgery was performed in eight patients. Seizure outcome was good in all. Two patients became seizure-free, one patient had a single prolonged seizure five days postoperatively, four patients had a significant seizure reduction of more than 75 % and one patient had a seizure reduction of more than 50 % after surgery without additional neurologic deficits. In conclusion, patients with TSC and drug-resistant epilepsy may benefit from epilepsy surgery with reduction in frequency and severity of seizures as well as improved mental and behavioural development leading to a better quality of life. In view of recent developments in functional and metabolic imaging, primary epileptogenic lesions will be more easily detectable in patients with diffuse brain involvement in TSC and surgical treatment may be more specifically applied at an earlier age to a selected subgroup of patients with this disorder.

Child↗
PubMed1990

Tuberous sclerosis in pregnancy.

Tuberous sclerosis is an autosomal dominant disorder of hamartoma formation in which manifestations may occur in skin, brain, and viscera. In the past, it was believed that the typical presentation included seizures, mental retardation, and facial angiofibromas ("adenoma sebaceum"). This disorder is now recognized to show wide variability of expression. There are only four cases of tuberous sclerosis in pregnancy in the literature. Two of these had favorable maternal and fetal outcomes and the remaining two presented with serious maternal and fetal complications. These included acute intra-abdominal bleeding due to a ruptured renal tumor, which led to renal failure requiring hemodialysis, and severe preeclampsia with pathologically enlarged kidneys noted at the time of cesarean section. This study presents two more cases of tuberous sclerosis in pregnancy. The first case had renal involvement with bleeding into a renal cyst, renal failure, preeclampsia, and severe intrauterine growth retardation. The second case was complicated by preterm premature rupture of the membranes and preterm labor. Renal involvement appears to be the single most important prognostic factor in pregnancies with tuberous sclerosis. Renal evaluation should be performed in any patient who presents for preconceptional counseling.

Adult↗
PubMed1987

Tuberous sclerosis: magnetic imaging of the brain.

The results of the magnetic resonance imaging of three patients with proven tuberous sclerosis will be discussed. Cortical tubers and subcortical areas of junctional dysmyelination can be demonstrated clearly by MRI, whereas small calcifications may be missed because of low contrast if the chosen slice thickness should be too large. It is suggested that MRI should be applied to those patients with suspected tuberous sclerosis, in which CT has failed to demonstrate typical subependymal calcifications and to those in which doubts about the definite diagnosis remain. This should be done in order to improve the accuracy of genetic counselling. It may be argued that all patients with tuberous sclerosis have to be referred to MRI, because transformation of subependymal nodules into diffusely infiltrating gliomas can be detected earlier if comparison with a former MRI study is possible.

Adult↗
PubMed2004

Conservative management of pulmonary lymphangioleiomyomatosis and tuberous sclerosis complicated by renal angiomyolipomas in pregnancy.

Both pulmonary lymphangioleiomyomatosis and tuberous sclerosis are rare diseases. The optimal management in pregnancy is unclear. A primigravida with pulmonary lymphangioleiomyomatosis and tuberous sclerosis complicated by worsening renal function secondary to angiomyolipomas was managed conservatively. Favorable maternal and neonatal outcomes were achieved. Pulmonary lymphangioleiomyomatosis is a consideration in tuberous sclerosis patients with respiratory symptoms. Tuberous sclerosis patients with pulmonary lymphangioleiomyomatosis require cautious and calculated expectant management in an effort to avoid adverse outcomes.

Adult↗
PubMed1994

9q34 loss of heterozygosity in a tuberous sclerosis astrocytoma suggests a growth suppressor-like activity also for the TSC1 gene.

Tuberous sclerosis is an autosomal dominant disease whose characteristic feature is the development of multiple hamartomas in a variety of organs and tissues. Two major loci have been identified so far: TSC1 on chromosome 9q34 and TSC2 on chromosome 16p13.3. Loss of heterozygosity at 16p13.3-associated markers has been recently observed in hamartomatous lesions of some tuberous sclerosis patients. Here we report the first evidence of loss of heterozygosity at the TSC1 critical region in a giant cell astrocytoma of a familial tuberous sclerosis case. Segregation analysis showed that the 9q34 haplotype lost carried the putative normal TSC1 gene. These data support the hypothesis of both a germline and somatic loss-of-function mutation for the development of tuberous sclerosis hamartomas and suggest a tumor-suppressor-like activity also for the TSC1 gene product. Finally, the possible significance of a second small region of loss of heterozygosity at 9p21, found in the same astrocytoma, is discussed.

Astrocytoma↗
PubMed2005

Modulation of fructokinase activity of potato (Solanum tuberosum) results in substantial shifts in tuber metabolism.

Potato plants (Solanum tuberosum L. cvs Desiree and Record) transformed with sense and antisense constructs of a cDNA encoding the potato fructokinase StFK1 exhibited altered transcription of this gene, altered amount of protein and altered enzyme activities. Measurement of the maximal catalytic activity of fructokinase revealed a 2-fold variation in leaf (from 90 to 180% of wild type activity) and either a 10- or 30-fold variation in tuber (from 10 or 30% to 300% in Record and Desiree, respectively) activity. The comparative effect of the antisense construct in leaf and tuber tissue suggests that this isoform is only a minor contributor to the total fructokinase activity in the leaf but the predominant isoform in the tuber. Antisense inhibition of the fructokinase resulted in a reduced tuber yield; however, its overexpression had no impact on this parameter. The modulation of fructokinase activity had few, consistent effects on carbohydrate levels, with the exception of a general increase in glucose content in the antisense lines, suggesting that this enzyme is not important for the control of starch synthesis. However, when metabolic fluxes were estimated, it became apparent that the transgenic lines display a marked shift in metabolism, with the rate of redistribution of radiolabel to sucrose markedly affected by the activity of fructokinase. These data suggest an important role for fructokinase, acting in concert with sucrose synthase, in maintaining a balance between sucrose synthesis and degradation by a mechanism independent of that controlled by the hexose phosphate-mediated activation of sucrose phosphate synthase.

Carbohydrate Metabolism↗
PubMed2006

The response of carbohydrate metabolism in potato tubers to low temperature.

This work investigates the possible causes of cold-induced sweetening in potato by examining the impact of low temperature on carbohydrate metabolism in mature tubers. Metabolism in tuber discs was monitored by determining the redistribution of radiolabel following incubation in [U-(14)C]glucose. Estimates of flux based on the specific activity of hexose phosphates established that while incubation at 4 degrees C resulted in an immediate restriction in pathways of carbohydrate oxidation relative to activity at 25 degrees C, there was no corresponding increase in flux to soluble sugars. In contrast, prior storage at low temperature stimulated flux to sugars at both 4 and 25 degrees C. Comparison of (14)CO(2) release from specifically labeled glucose and gluconate fed to tuber discs at 4 and 25 degrees C indicated that flux through glycolysis was preferentially restricted relative to the oxidative pentose phosphate pathway at low temperature, irrespective of prior storage temperature. However, the degree of randomization of label between positions C1 and C6 in the fructosyl moiety of sucrose following metabolism of [1-(13)C]glucose established that there was no preferential inhibition of the recycling of triose phosphates to hexose phosphates at low temperature. These results indicate that sugar accumulation in tubers during storage in the cold is not a direct consequence of a constraint in carbohydrate oxidation, despite preferential restriction of glycolysis at low temperature. It is concluded that the cold lability of enzymes catalyzing the conversion of fructose 6-phosphate to fructose 1,6-bisphosphate is not a major factor in cold-induced sweetening in plants and that this widely held hypothesis should be abandoned.

Carbohydrate Metabolism↗
PubMedDate not supplied

Application of magnetization transfer imaging for intracranial lesions of tuberous sclerosis.

PURPOSE: Our goal was to assess the effectiveness of magnetization transfer imaging (MTI) and the usefulness of the magnetization transfer ratio (MTR) in tuberous sclerosis (TS). METHOD: T2- and T1-weighted SE images with saturation pulse on/off before and after gadolinium enhancement in 10 patients with TS were obtained. The numbers of subependymal nodule (SEN), cortical tuber, and white matter (WM) abnormality detected on T1-, proton density, T2-, and MT T1-weighted SE images were compared. The contrast-to-noise ratio (C/N) on T1-, MT T1-, Gd T1-, and Gd MT T1-weighted SE images and MTR (1-Msat/MO) on each set of saturation/nonsaturation images for each lesions were calculated. Mean MTRs (mMTRs) of WM and gray matter (GM) from seven normal volunteers were also obtained. RESULTS: MT T1-weighted SE images always depicted all lesions seen on conventional MRI and allowed depiction of more SENs (n = 80), cortical tubers (n = 197), and WM abnormalities (n = 82) than did T1-weighted (n = 58/85/33), proton density (n = 41/108/36), or T2-weighted (n = 48/121/46) SE images. The best C/N was obtained from Gd MT T1-weighted SE images in SENs and from MT T1-weighted SE images in other lesions. mMTRs of normal WM and GM were 36.43 and 29.42%, respectively. Cortical tubers and WM abnormalities had measured MTRs that were statistically equal to MTRs of GM in normal subjects (p < 0.005). MTRs of SENs showed lower mean (25.55%) and greater diversity (SD +/- 5.30), compared with MTRs of other lesions and normal GM and WM. One SEN with MTR of 20.72% was pathologically confirmed to be subependymal giant cell astrocytoma (SGCA). Nine SENs had measured MTR below 20.72% and six nodules among these were located in the region of the foramen of Monro, which is the characteristic location of SGCA. CONCLUSION: MTI may be effective in detecting all cranial lesions of TS. MTR may increase the specificity of MRI because it can differentiate the histopathologic subtypes and track and evolution of SEN into SGCA.

Adolescent↗
PubMed2003

The tuberous sclerosis complex and its highly variable manifestations.

PURPOSE: Tuberous sclerosis is an autosomal dominant neurocutaneous syndrome affecting multiple organ systems and demonstrating highly variable clinical manifestations. Mutations in 2 tumor suppressor genes, TSC1 and TSC2, are linked to the evolution of the hamartomatous lesions. We describe the incidence and epidemiology, variable clinical manifestations and their relationships to renal pathology, and the management of morbid sequelae. MATERIALS AND METHODS: Using the search term tuberous sclerosis, we performed a MEDLINE search of the literature identifying 3,196 articles and selected those from urological, surgical, oncological, genetic and pediatric journals. Special focus was placed on the incidence and management of renal lesions and on different clinical manifestations and how they relate to renal tumors. RESULTS: Due to improved identification of the variable phenotypic expression, the reported incidence has increased. TSC1 and TSC2 mutations are related to various phenotypic manifestations and risks of malignancy, such as an increased incidence of the TSC2 mutation in patients with renal cell carcinoma. Renal sparing surgery and selective embolization techniques have mitigated the morbidity of the lesions. CONCLUSIONS: We now have a better understanding of the variability at the genotypic and phenotypic levels of the disease. We recommend that patients with tuberous sclerosis complex be evaluated by a multidisciplinary group of clinicians, including urologists, dermatologists, neurologists, pediatricians and geneticists. Close attention to these manifestations is necessary to ensure appropriate treatment of the sequelae of the tuberous sclerosis complex.

Cardiovascular Diseases↗
PubMed2005

Cassava plants with a depleted cyanogenic glucoside content in leaves and tubers. Distribution of cyanogenic glucosides, their site of synthesis and transport, and blockage of the biosynthesis by RNA interference technology.

Transgenic cassava (Manihot esculenta Crantz, cv MCol22) plants with a 92% reduction in cyanogenic glucoside content in tubers and acyanogenic (<1% of wild type) leaves were obtained by RNA interference to block expression of CYP79D1 and CYP79D2, the two paralogous genes encoding the first committed enzymes in linamarin and lotaustralin synthesis. About 180 independent lines with acyanogenic (<1% of wild type) leaves were obtained. Only a few of these were depleted with respect to cyanogenic glucoside content in tubers. In agreement with this observation, girdling experiments demonstrated that cyanogenic glucosides are synthesized in the shoot apex and transported to the root, resulting in a negative concentration gradient basipetal in the plant with the concentration of cyanogenic glucosides being highest in the shoot apex and the petiole of the first unfolded leaf. Supply of nitrogen increased the cyanogenic glucoside concentration in the shoot apex. In situ polymerase chain reaction studies demonstrated that CYP79D1 and CYP79D2 were preferentially expressed in leaf mesophyll cells positioned adjacent to the epidermis. In young petioles, preferential expression was observed in the epidermis, in the two first cortex cell layers, and in the endodermis together with pericycle cells and specific parenchymatic cells around the laticifers. These data demonstrate that it is possible to drastically reduce the linamarin and lotaustralin content in cassava tubers by blockage of cyanogenic glucoside synthesis in leaves and petioles. The reduced flux to the roots of reduced nitrogen in the form of cyanogenic glucosides did not prevent tuber formation.

Biological Transport, Active↗
PubMed1994

A population study of renal disease in patients with tuberous sclerosis.

OBJECTIVE: To establish the prevalence of renal disease, asymptomatic renal lesions and possible renal symptoms in a geographically defined population of individuals with tuberous sclerosis. PATIENTS AND METHODS: The study involved 131 patients (64 men, 67 women) with tuberous sclerosis who were resident in nine of the districts within the Wessex Region and three Bristol Health Districts and who had been identified by a prevalence study [1]. The patients' mean age was 22 years (range 6 months-74 years). Established renal disease was identified by history. Where possible individuals were seen and were examined. Specific enquiry was made for flank pain and macroscopic haematuria. Renal ultrasound, blood pressure measurement and urine analysis was offered to all individuals with tuberous sclerosis who were resident in the Bath Health District. RESULTS: Eight patients (6%) had a history of either renal polycystic kidney disease (two patients) or haemorrhage from renal angiomyolipomas (five female patients, one male patient). A further 21% of female and 3% of male patients had a history of severe flank pain or haematuria. Renal ultrasound screening revealed abnormalities in 10 of 21 individuals; angiomyolipomas > 1 cm were found in seven and were twice as common in female patients. CONCLUSIONS: Regular clinical review of individuals with tuberous sclerosis should include enquiry for renal symptoms and abdominal examination. Lesions > 4 cm are most likely to be symptomatic but longitudinal studies are needed before renal ultrasound screening of adolescents or adults can be recommended.

Adolescent↗