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Biomedical subjects

Lili Miles

Publications and source records attributed to Lili Miles.

15 recordsLinked to original sources

Adult neurological function following neonatal hypoxia-ischemia in a mouse model of the term neonate: water maze performance is dependent on separable cognitive and motor components.

BACKGROUND AND PURPOSE: Hypoxic-ischemic injury in term neonates remains a significant cause of long-term neurological morbidity. The post-natal day 10 (P10) mouse is accepted as a model for the term human. This study was designed to assess the relationships between the duration of hypoxia-ischemia (HI) on P10 and the structural and functional neurological deficits that appear in the adult mouse as a consequence. METHODS: Post-natal day 10 129T2xC57Bl/6 F1 hybrid mice were subjected to 0, 45, 60 or 75 min of hypoxia-ischemia using the Rice-Vannucci model. Beginning on P50 these mice were tested over the next 8 weeks using zero maze, locomotor activity, novel object recognition, cued, hidden and reduced Morris water mazes, delayed probe trials and response to apomorphine injection. Brain weights and histology were obtained at the end of testing. RESULTS: The degree of structural and behavioral abnormalities in adult mice correlated with the duration of hypoxia-ischemia on P10. Useful behavioral tests for separating adult mice according to duration of hypoxia-ischemia on P10 include locomotor activity, the Morris water mazes and response to apomorphine. We found cued "learning" persisted, although latencies increased, with increasing HI time while spatial learning decayed as a function of HI time. Severe HI injury involving the ventral hippocampus resulted in excessive locomotor activity. CONCLUSIONS: After correcting for motor deficits, there is evidence for persistence of "cued" learning but not spatial learning with increasing hypoxia-ischemia time on P10 in this model system.

Aging↗

Non-lethal congenital hypotonia due to glycogen storage disease type IV.

Glycogen storage disease type IV (GSD-IV) is an autosomal recessive genetic disorder due to a deficiency in the activity of the glycogen branching enzyme (GBE). A deficiency in GBE activity results in the accumulation of glycogen with fewer branching points and long, unbranched outer chains. The disorder results in a variable phenotype, including musculoskeletal, cardiac, neurological, and hepatic involvement, alone or in continuum, which can be identified at any stage of life. The classic form of GSD-IV is a hepatic presentation, which presents in the first 18 months of life with failure to thrive, hepatomegaly, and cirrhosis that progresses to liver failure, resulting in death by age 5 years. A severe congenital musculoskeletal phenotype with death in the neonatal period has also been described. We report an unusual case of congenital musculoskeletal presentation of GSD-IV with stable congenital hypotonia, gross motor delay, and severe fibro-fatty replacement of the musculature, but no hepatic or cardiac involvement. Molecular analysis revealed two novel missense mutations with amino acid changes in the GBE gene (Q236H and R262C), which may account for the mild phenotype.

1,4-alpha-Glucan Branching Enzyme↗

Histologic spectrum of nonalcoholic fatty liver disease in morbidly obese adolescents.

BACKGROUND & AIMS: To characterize the spectrum of nonalcoholic fatty liver disease (NAFLD) in morbidly obese adolescents, we correlated liver histology with clinical features and compared findings with reported adult data. We hypothesized that NAFLD would be less severe as a result of younger age and shorter duration of obesity, but portal inflammation and fibrosis would be more prevalent. METHODS: Cross-sectional study was made of 41 adolescent subjects, 13-19 years old (mean, 16 years), 61% female, 83% non-Hispanic white, mean body mass index 59 kg/m(2), undergoing gastric bypass with liver biopsy. Liver biopsies were graded and staged as proposed by the NASH Clinical Research Network. Data were analyzed by using descriptive statistics, analysis of variance, and Fisher exact tests. RESULTS: Eighty-three percent had NAFLD: 24% steatosis alone, 7% isolated fibrosis with steatosis, 32% nonspecific inflammation and steatosis, and 20% nonalcoholic steatohepatitis (NASH). Twenty-nine percent had fibrosis; none had cirrhosis. Abnormal ALT (P = .05) and AST (P = .01) were more prevalent in NASH. Mean fasting glucose was significantly higher in NASH (P = .05), but prevalence of the metabolic syndrome was not significantly different. CONCLUSIONS: NAFLD was very prevalent in morbidly obese adolescents, but severe NASH was uncommon. In contrast to morbidly obese adults, lobular inflammation, significant ballooning, and perisinusoidal fibrosis were rare, whereas portal inflammation and portal fibrosis were more prevalent, even in those who did not meet criteria for NASH. These findings might support use of a modified scoring system for pediatric NASH. Presence of the metabolic syndrome in morbidly obese adolescents did not distinguish NASH from steatosis alone.

Adolescent↗

Granular cell astrocytoma of the cerebellum: report of the first case.

Granular cell astrocytomas are an uncommon morphologic variant of infiltrating gliomas characterized by relatively large tumor cells with granular cytoplasm occupying variable proportions of the tumor. These tumors are thought to be more aggressive than similar tumors with no granular cell component. The tumor occurred in a 9-year-old girl who was immunocompromised owing to liver transplantation. Histologically, the tumor corresponded to World Health Organization grade II. It extensively infiltrated the cerebellum and was composed, predominantly, of large cells with eosinophilic granular cytoplasm. These cells coexpressed glial fibrillary acidic protein and CD68. Of the 49 cases of granular cell astrocytomas reported to date, none have involved the cerebellum. The tumor described herein represents the first case of cerebellar granular cell astrocytoma. Pathologic features and diagnostic pitfalls are explored.

Astrocytoma↗

Investigation of children for mitochondriopathy confirms need for strict patient selection, improved morphological criteria, and better laboratory methods.

We studied muscle biopsies of 103 pediatric patients in whom clinical suspicion for disorder of energy metabolism was highest in 13 patients, intermediate in 8 patients, and lowest in 82 patients. Electron transport complex (ETC) enzyme activity measurements were available in 96 of 103 patients. Most children with unclassified encephalopathy before biopsy had negative or equivocal morphological and biochemical evaluation for disorder of energy metabolism (72/85). The incidence of ETC abnormality and morphological abnormality in muscle from 39 patients with clinical encephalomyopathy (groups I, II, and III) was 20% and 38%, respectively. In 21 children with high or intermediate clinical suspicion of mitochondriopathy, light microscopy was confirmative in 12, ultrastructure was confirmative in 15, and major ETC abnormality was present in only 4 (29%) of 14. In 82 children with lower clinical suspicion of mitochondriopathy, morphological criteria at both the light and electron microscopic level were absent, and major abnormality of ETC activity was uncommon, in 9 (11%) of 82. Partial reductions of ETC activity occurred in 15 (18%) of 82, but are of uncertain significance. Ragged blue fibers were more prevalent in infants with mitochondriopathy than ragged red fibers. Increase of large, but not small, subsarcolemmal mitochondrial aggregates based on succinate dehydrogenase histochemistry is a useful indicator for mitochondriopathy. Thus, a distinction should be made between small aggregates (normal) and large aggregates. Using strict criteria to define pathological mitochondria, we concluded that electron microscopy is a powerful tool in the diagnosis of mitochondriopathy mainly when clinical suspicion is high. We found no consistent difference in the frequency of mitochondrial "proliferation" as currently defined or in citrate synthase activity in any group. Better patient selection in infants and children and better methods for investigation of mitochondriopathy are needed.

Adolescent↗

Adenomatoid odontogenic tumor mimicking a dentigerous cyst.

Adenomatoid odontogenic tumor (AOT) is a slow-growing, asymptomatic and uncommon lesion that arises from odontogenic epithelium with inductive effects on connective tissue. The more common variant is the follicular type, which involves an unerupted tooth and is often mistaken for a dentigerous cyst. Histopathologic examination demonstrates cuboidal or spindle-shaped epithelial cells forming aggregates or rosette-like structures with minimal connective tissue, and cuboidal or low columnar cells forming glandular duct-like structures. Treatment is complete enucleation, and recurrences are rare. We presented a case of AOT in a 14-year-old male presenting as a cystic mass around an unerupted tooth.

Adolescent↗

Ubiquinol: a potential biomarker for tissue energy requirements and oxidative stress.

BACKGROUND: Coenzyme Q (CoQ) has been suggested as a biomarker for tissue redox status. The aims are (1) to compare ubiquinol-9, ubiquinol-10, ubiquinone-9, ubiquinone-10, total CoQ content and CoQ redox ratio in quadriceps muscle, heart, brain and liver tissues of mdx mice with wild-type controls; and (2) to determine if ubiquinol content and CoQ redox ratio changes are associated with pathological findings in mdx mouse. METHODS: CoQ contents were determined in homogenized quadriceps muscle, heart, liver and brain of age-matched mdx and wild-type control mice by HPLC-EC. Light and electron microscopy studies were conducted using standard pathology methods. RESULTS: Ubiquinol-9 and ubiquinol-10 concentrations are significantly increased in quadriceps and heart muscle of mdx mouse. Increased redox ratios of coenzyme Q(9) and coenzyme Q(10) are also evident in quadriceps, heart and liver tissues in mdx mouse, but not brain. Pathological examination shows marked myofiber regeneration and evidence of mitochondrial proliferation for mdx muscle. CONCLUSIONS: Evidence that changes in ubiquinol content and CoQ redox ratio are related to pathological features in mdx skeletal and heart myofibers suggests that tissue ubiquinol content and CoQ redox ratio may be useful biomarkers for evaluating muscle disorders associated with mitochondrial proliferation and defects in oxidative phosphorylation.

Animals↗

Muscle coenzyme Q: a potential test for mitochondrial activity and redox status.

The aim of this study is to determine whether coenzyme Q (CoQ) muscle concentrations and redox state are associated with pathologic changes in muscle biopsy specimens. Skeletal muscle biopsies were collected (January 2002-February 2004) and underwent pathologic evaluation. Quadriceps specimens (n = 47) were stratified accordingly: Group 1, controls without evidence of pathologic abnormalities; Group 2, type I myofiber predominance; Group 3, type II myofiber atrophy; Group 4, lower motor unit disease; and Group 5, muscular dystrophy. Ubiquinol-10, ubiquinone-10, total coenzyme Q10 (CoQ10), coenzyme Q9 (CoQ9), total CoQ (CoQ9+CoQ10) concentrations were analyzed in biopsy muscle by high-performance liquid chromatography. Ubiquinone-10, total CoQ10, and total CoQ concentrations were significantly decreased in Group 5. Significant positive correlations (r congruent with 0.40) were found between muscle ubiquinone-10, total CoQ10, and total CoQ concentrations vs the percentage of myofibers having subsarcolemmal mitochondrial aggregates. CoQ redox ratio and the fraction CoQ9/total CoQ were negatively correlated with subsarcolemmal mitochondrial aggregates. A significant correlation (r = 0.328) also occurred between ubiquinol-10 concentration and citrate synthase activity. This study suggests that total CoQ concentration provides a new method for estimating mitochondrial activity in biopsy muscle; and that the muscle CoQ test is feasible and potentially useful for diagnosing CoQ deficiency states.

Adolescent↗

Tailgut cyst in a child.

Tailgut cyst, or retrorectal cystic hamartoma, is a rare congenital lesion found in the presacral space. The lesion has been infrequently reported in the literature. We report the MRI findings of a tailgut cyst in a 2-year-old girl who presented with a sacral dimple and skin discoloration.

Child, Preschool↗

Measurement of reduced and oxidized coenzyme Q9 and coenzyme Q10 levels in mouse tissues by HPLC with coulometric detection.

BACKGROUND: Ubiquinone-responsive multiple respiratory chain dysfunction due to coenzyme Q(10) (CoQ(10)) deficiency has been previously identified in muscle biopsies. However, previous methods are unreliable for estimating CoQ(10) redox status in tissue. We developed an accurate method for measuring tissue concentrations of reduced and oxidized coenzyme Q (CoQ). METHODS: Mouse tissues were weighed in the frozen state and homogenized with cold 1-propanol on ice. After solvent extraction, centrifugation and filtration, the filtrate was subsequently analyzed by reversed-phase HPLC with coulometric detection. RESULTS: Reference calibration curves were used to determine reduced and oxidized coenzyme Q(9) (CoQ(9)) and CoQ(10) concentrations in tissues. The method is sensitive ( approximately 15 microg/l), reproducible (6% CV) for CoQ(9) and CoQ(10), and linear up to 20 mg/l for CoQ(9) and CoQ(10). Analytical recoveries were 90-104%. In mouse tissues the amounts of total CoQ (TQ) ranged from 261 to 1737 nmol/g of protein. Total CoQ(9) levels are comparable with the values of those previously reported. CoQ is found to be mostly in the reduced form in mouse liver ( approximately 87%), heart ( approximately 60%), and muscle tissues ( approximately 58%); in the brain, most of the CoQ is in the oxidized state ( approximately 65%). CONCLUSION: This procedure provides a precise, sensitive, and direct assay method for the determination of reduced and oxidized CoQ(9) and CoQ(10) in mouse hindleg muscle, heart, brain, and liver tissues.

Animals↗

Age-related changes in plasma coenzyme Q10 concentrations and redox state in apparently healthy children and adults.

BACKGROUND: Coenzyme Q10 (CoQ) is an endogenous enzyme cofactor, which may provide protective benefits as an antioxidant. Because age-related CoQ changes and deficiency states have been described, there is a need to establish normal ranges in healthy children. The objectives of this study are to determine if age-related differences in reduced CoQ (ubiquinol), oxidized CoQ (ubiquinone), and CoQ redox state exist in childhood, and to establish reference intervals for these analytes in healthy children. METHODS: Apparently healthy children (n=68) were selected from individuals with no history of current acute illness, medically diagnosed disease, or current medication treatment. Self-reported healthy adults (n=106) were selected from the ongoing Princeton Follow-up Study in greater Cincinnati. Participants were assessed for lipid profiles, ubiquinol concentration, ubiquinone concentration, total CoQ concentration, and CoQ redox ratio. RESULTS: Mean total CoQ and ubiquinol concentrations are similar in younger children (0.2-7.6 years) and adults (29-78 years); however, lipid-adjusted total CoQ concentrations are significantly increased in younger children. Also CoQ redox ratio is significantly increased in younger and older children compared with adults. CONCLUSIONS: Elevated CoQ and redox ratios in children may be an indication of oxidative stress effects, which are associated with early development of coronary heart disease.

Adolescent↗

The histologic differentiation of oral condyloma acuminatum from its mimics.

OBJECTIVE: The purpose of this study was to determine which histologic features could enable one to distinguish oral condyloma, as defined by the detection of human papillomavirus (HPV) DNA through in situ hybridization, from its mimics. STUDY DESIGN: Thirty-two paraffin-embedded specimens from 28 patients that were clinically suggestive of oral condyloma were analyzed histologically and through in situ hybridization with a consensus HPV probe. RESULTS: HPV DNA was detected in 17/32 (53%) of the lesions; no additional positive cases were detected after polymerase chain reaction amplification. Only 5 of the 17 virus-positive cases were considered to be histopathologically unequivocal for condyloma. The histologic features significantly associated with HPV detection were nonuniform perinuclear halos, often in association with epithelial crevices (P =.02), and papillomatosis (P =.02). Each of the 17 patients who were HPV-positive had either HPV-6 or HPV-11, a finding that is similar to those for condyloma involving the penis and vulva/vagina. CONCLUSION: Differentiation between oral condyloma and its mimics is best accomplished by using a combination of histologic, clinical, and in situ viral studies.

Adult↗