Javier Rodríguez-García

Evolution of Serum Lipids and Lipoprotein (a) Levels in Epileptic Children Treated With Carbamazepine, Valproic Acid, and Phenobarbital

The concentration levels of serum lipids and lipoprotein (a) were measured in 20 children receiving carbamazepine, 25 children receiving valproic acid, and 5 children receiving phenobarbital at the following times: (1) during chronic treatment while eating a normal diet, (2) during chronic treatment while eating a low-fat diet (children treated with carbamazepine and phenobarbital with high levels of total choleserol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), and (3) 3 months after the end of treatment with antiepileptic drugs. Patients during chronic treatment and eating a normal diet revealed significant changes in lipids, but when we reevaluated the groups of children treated with carbamazepine and phenobarbital when they were eating a low-fat diet and reevaluated the three groups of children 3 months after the end of treatment, a complete return to normal of all parameters was observed. These data demonstrate that the changes induced by these drugs are transient, reversible, and influenced by a low-fat diet. (J Child Neurol 2006;21:48—53).

Neuron-specific enolase, nucleotides, nucleosides, purine bases, oxypurines and uric acid concentrations in cerebrospinal fluid of children with meningitis

To determine the effects of meningitis on cerebral energy metabolism, cerebrospinal fluid concentrations of adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, adenine, guanine, hypoxanthine, xanthine and urate were determined by high-performance liquid chromatography, and neuron-specific enolase by an enzyme immunoassay method, in 100 children with meningitis (45 bacterial, 46 viral and nine tuberculous), aged between 1 month and 13 years, and in 160 age-matched controls. Compared with controls, patients with bacterial meningitis showed high concentrations of hypoxanthine, xanthine and urate; patients with viral meningitis showed high concentrations of inosine, guanosine, xanthine, urate and neuron-specific enolase; and patients with tuberculous meningitis showed very high concentrations of inosine, xanthine and urate. Xanthine and urate concentrations were significantly higher in patients with tuberculous meningitis than in patients with viral or bacterial meningitis. These results suggest that in the acute stage of bacterial, viral and tuberculous meningitis, neuronal energy metabolism may be altered. The measurement of cerebrospinal xanthine and uric acid concentrations may be useful for the early diagnosis of a tuberculous origin.

Cerebrospinal fluid purine metabolite and neuron-specific enolase concentrations after febrile seizures

If febrile seizures cause significant compromise of neuronal metabolism (whether permanent or reversible), this should be reflected in an increase in the cerebrospinal fluid concentrations of neuron-specific enolase (NSE) and/or adenosine triphosphate (ATP) breakdown products. In the present study, AMP, IMP, inosine, adenosine, guanosine, adenine, guanine, hypoxanthine, xanthine, uric acid and NSE concentrations were determined in the cerebrospinal fluid of 90 children 1 h after febrile seizure (73 simple febrile seizures (SFS); 17 complex febrile seizures (CFS)), and in a control group of 160 children. There was no statistically significant difference between the SFS group and the control group for any of the substances determined, suggesting that SFS neither significantly depletes neuronal ATP concentration, nor significantly increases NSE concentration; thus, SFS do not appear to constitute a threat to neuronal integrity. However, patients with CFS showed significantly lower IMP concentrations and significantly higher adenine concentrations than controls, and significantly higher AMP concentrations than SFS patients; these results suggest that CFS may affect energy metabolism in the brain. However, NSE concentrations were normal in the cerebrospinal fluid of both SFS and CFS patients, suggesting that neither type of seizure causes significant neuronal damage, at least early after the seizure.

Concentrations of Nucleotides, Nucleosides, Purine Bases, Oxypurines, Uric Acid, and Neuron-Specific Enolase in the Cerebrospinal Fluid of Children With Sepsis

To determine the effects of sepsis on cerebral energy metabolism, the cerebrospinal fluid adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, hypoxanthine, xanthine, and urate concentrations were determined by high-performance liquid chromatography and the neuron-specific enolase levels by means of an enzyme immunoassay method in 32 children with sepsis, without meningitis, aged between 2 months and 13 years, and in 160 age-matched controls. The septic group had significantly higher cerebrospinal fluid concentrations of inosine, adenosine, xanthine, and urate than controls. These results suggest that sepsis could provoke some degree of neuronal hypoxia and significant alterations of cerebral energy metabolism homeostasis. (J Child Neurol 2001;16:704-706).

High Incidence of Hypoglycemia in Stable Insulin-Treated Type 2 Diabetes Mellitus: Continuous Glucose Monitoring vs. Self-Monitored Blood Glucose. Observational Prospective Study

OBJECTIVES Hypoglycemia is a limiting factor in the achievement of strict glycemic control. The primary objective of this 9-week study was to determine the frequency of hypoglycemia in patients with stable insulin-treated type 2 diabetes mellitus by comparing self-monitored blood glucose (SMBG) measurement with continuous glucose monitoring (CGM). METHODS This was an observational prospective study. Included in the study were 63 stable, insulin-treated patients with type 2 diabetes. They were instructed to record 2 daily capillary blood glucose readings, pre- and/or postprandial, in a sequential way during 8 consecutive weeks. A CGM system was worn during an additional week. We evaluated the frequency of hypoglycemia using the 8-week SMBG profile and the 1 CGM week. RESULTS SMBG revealed that 50% of the patients had experienced hypoglycemia. CGM found hypoglycemia in 59% of patients. Significantly higher percentages of hyperglycemic and hypoglycemic episodes were detected by CGM than by capillary blood glucose measurements (61.1% vs. 50.8%; p=0.047) and (3.8% vs. 1.7%; p=0.016); 33% of patients experienced nocturnal hypoglycemia, and 19% of patients who had no data concerning hypoglycemia recorded in the capillary blood glucose diary had experienced hypoglycemia as measured by CGM, and the hypoglycemia occurred mainly during the nocturnal period. CONCLUSIONS In stable well-controlled, insulin-treated patients with type 2 diabetes, CGM showed higher numbers of hypoglycemic events than did SMBG, especially at night. CGM is a useful tool that provides clinically valuable information about glucose control in these patients.

Neuron-specific enolase levels in the cerebrospinal fluid of neurologically healthy children.

Levels of neuron-specific enolase (NSE) levels in the cerebrospinal fluid (CSF) of children without neurological disease were assessed. CSF samples were obtained from 37 subjects aged between 1 month and 13 years. All subjects had undergone lumbar puncture for diagnostic purposes, and were subsequently shown not to be suffering any form of neurological disease. NSE levels in CSF were determined by an enzyme immunoassay method. NSE level ranged from below the detection limit to 4.8 ng/ml (1.52+/-1.01 ng/ml). The present results may be useful as a basis for defining reference levels of NSE in CSF in post-neonatal children.

Transferability of results obtained for sodium, potassium and chloride ions with different analysers

In this study we have assessed transferability in seven different analysers commonly used in clinical chemistry laboratories to measure sodium, potassium and chloride ions. The inaccuracy and linearity of the techniques were satisfactory in most cases, and therefore all the equipment may be used in both pathological and normal ranges of the electrolytes evaluated. In most cases it was possible to correct the inaccuracy. The equipment which gave the best performance when analysing the three ions assessed after considering the Process Capability Index (CPI) and Performance Index (PI) was Nova-5. According to Hyltoft-Petersens criteria, the results obtained for the three ions with the different analysers cannot be used indiscriminately, apart from potassium. However, after comparison of the results obtained by indirect potentiometry with those obtained by other techniques, we can conclude that the transferability of results is possible in almost every case, as standard deviation from regression (Sy,x) was lower than the permissible analytical error.

Humanized Medium (h7H) Allows Long-Term Primary Follicular Thyroid Cultures From Human Normal Thyroid, Benign Neoplasm, and Cancer

CONTEXT Mechanisms of thyroid physiology and cancer are principally studied in follicular cell lines. However, human thyroid cancer lines were found to be heavily contaminated by other sources, and only one supposedly normal-thyroid cell line, immortalized with SV40 antigen, is available. In primary culture, human follicular cultures lose their phenotype after passage. We hypothesized that the loss of the thyroid phenotype could be related to culture conditions in which human cells are grown in medium optimized for rodent culture, including hormones with marked differences in its affinity for the relevant rodent/human receptor. OBJECTIVE The objective of the study was to define conditions that allow the proliferation of primary human follicular thyrocytes for many passages without losing phenotype. METHODS Concentrations of hormones, transferrin, iodine, oligoelements, antioxidants, metabolites, and ethanol were adjusted within normal homeostatic human serum ranges. Single cultures were identified by short tandem repeats. Human-rodent interspecies contamination was assessed. RESULTS We defined an humanized 7 homeostatic additives medium enabling growth of human thyroid cultures for more than 20 passages maintaining thyrocyte phenotype. Thyrocytes proliferated and were grouped as follicle-like structures; expressed Na+/I- symporter, pendrin, cytokeratins, thyroglobulin, and thyroperoxidase showed iodine-uptake and secreted thyroglobulin and free T3. Using these conditions, we generated a bank of thyroid tumors in culture from normal thyroids, Graves hyperplasias, benign neoplasms (goiter, adenomas), and carcinomas. CONCLUSIONS Using appropriate culture conditions is essential for phenotype maintenance in human thyrocytes. The bank of thyroid tumors in culture generated under humanized humanized 7 homeostatic additives culture conditions will provide a much-needed tool to compare similarly growing cells from normal vs pathological origins and thus to elucidate the molecular basis of thyroid disease.

Levels of Pentosidine in the Vitreous of Eyes with Proliferative Diabetic Retinopathy, Proliferative Vitreoretinopathy and Retinal Detachment

BackgroundAdvanced glycosylation end products (AGEs) are thought to play an important role in the pathophysiology of diabetes. Particularly, these products have been implicated in the pathogenesis of proliferative diabetic retinopathy. The majority of these products are formed from a vast range of precursor molecules, the variable chemical nature of which contributes to AGE heterogeneity. There is a growing population of structurally defined AGE adducts such as pyrraline, pentosidine, CML and crossline that have been found to be elevated in diabetic tissues. In the present study, the levels of the glycoxidation product pentosidine were determined in vitreous samples obtained during vitrectomy from eyes with proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR), and retinal detachment (RD). Samples from cadaveric control eyes were also included in the study. The levels of pentosidine were compared among the groups.MethodsSeventy-three vitreous samples were collected from eyes undergoing vitrectomy for PDR (n=33), PVR (n=28) and RD (n=12). Eighteen samples from cadaveric control eyes were also included in the study. A modified Bradford’s method was used to assay protein content, and vitreous levels of pentosidine were determined by high-performance liquid chromatography after acid hydrolysis and pretreatment with SP-Sephadex. Statistical analyses were performed using a two-sided Mann–Whitney U test.ResultsThe levels of pentosidine [median (interquartile range)] were 0.92 (0.55–1.26) pmol/mg of protein in the PDR cases, 1.12 (0.46–1.80) pmol/mg of protein in PVR, and 1.02 (0.24–1.44) pmol/mg of protein in RD. In the cadaveric control eyes pentosidine levels were 0.97 (0.68–1.30) pmol/mg of protein. The pentosidine levels of the four groups did not differ significantly.ConclusionsThe levels of the glycoxidation product pentosidine (expressed as pmol/mg of protein) in the vitreous of eyes with PDR do not differ significantly from those in the vitreous of eyes with PVR, RD or cadaveric control eyes. Although these results do not refute the findings of previous studies that evaluated globally total AGE levels and the existence of diabetic vitreopathy, further investigation is needed to fully understand their relevance in this multifactorial disorder.

Levels of leptin, insulin, IGF-I, IGFBP-3, IL-6 and IL-8 in sera of patients with muscular dystrophy and mitochondrial encephalomyopathy

There is evidence that muscle forms part of endocrine networks, secreting/or responding to circulating agents such as leptin and interleukin-6 as well as the classical hormone insulin. To gain further insight into the possible role of these hormones and cytokines in muscle degenerative diseases, we investigate their concentrations in sera from patients with muscular dystrophy and mitochondrial encephalomyopathy. In 13 patients with muscular dystrophy, in eight patients with mitochondrial encephalomyopathy, and in 8 age-matched healthy control subjects, the concentrations of leptin, insulin, insulin-like growth factor I, insulin-like growth factor binding protein-3 (IGFBP-3), interleukin 6 and interleukin 8 in sera were determined. The only statistically significant difference between patient groups and controls was lower IGFBP-3 levels in patients with mitochondrial encephalomyopathy. Save the IGFBP-3, the other hormones and cytokines measured do not appear to be involved in the pathophysiology of these myopathies, at least in an endocrine, as opposed to a para-or autocrine, role.