SAFETY AND EFFICACY OF THYMIC PEPTIDES IN THE TREATMENT OF HOSPITALIZED COVID-19 PATIENTS IN HONDURAS.

Coronavirus disease 2019 (Covid-19) active cases continue to demand the development of safe and effective treatments. This is the first clinical trial to evaluate the safety and efficacy of oral thymic peptides. ; We conducted a nonrandomized phase 2 trial with a historic control group to evaluate the safety and efficacy of a daily 250-mg oral dose of thymic peptides in the treatment of hospitalized Covid-19 patients. Comparisons based on standard care from registry data were performed after propensity score matching. The primary outcomes were survival, time to recovery, and number of participants with treatment-related adverse events or side effects by day 20. ; A total of 44 patients were analyzed in this study: 22 in the thymic peptide group and 22 in the standard care group. There were no deaths in the intervention group compared to 24% mortality in standard care by day 20 (log-rank P=0.02). Kaplan-Meier analysis showed a significantly shorter time to recovery by day 20 in the thymic peptide group than in the standard care group (median, 6 days vs. 12 days; hazard ratio for recovery, 2.75 [95% confidence interval, 1.34 to 5.62]; log-rank P=0.002). No side effects or adverse events were reported. ; In patients hospitalized with Covid-19, the use of thymic peptides resulted in no side effects, adverse events, or deaths by day 20. Compared with the registry data, a significantly shorter time to recovery and mortality reduction were measured.

Physical and chemical characteristics of pitaya fruits at physiological maturity.

The aim of this study was to analyze the physical and chemical characteristics of the maturation process of pitaya fruit (Hylocereus undatus) to identify indicators that can be used to determine the point of physiological maturity and establish the optimal timing of physiological maturity for harvesting the fruit. A completely randomized experimental design was employed and four biological repeats were performed. Physiological maturity was assessed using various physical characteristics: longitudinal length (LL), equatorial diameter (ED), pericarp thickness (PeT), pulp thickness (PuT), fruit mass (FM), pulp mass (PuM), pericarp mass (PeM), pericarp percentage (%Pe), pulp percentage (%Pu), pulp/pericarp ratio (Pu/Pe), pericarp color index (CI), hue color angle (h°), lightness index (L*), chroma (C*), blue-yellow variation (b*), and green-red variation (a*). Additionally, chemical characteristics such as soluble solid content (SS), titratable acidity (TA), SS/TA ratio, and pH were screened. The data were statistically analyzed by fitting regression models and computing Pearson's correlation coefficients (P < 0.05). Physiological maturity in pitaya fruits occurred between the 30th and 32nd days after anthesis, and this proved to be the optimal period for harvest. At this time, the fruit was completely red with high SS, and had the recommended values of TA, pH, and SS/TA ratio. During this period, ED, PuT, FM, PuM, %Pu, and Pu/Pe increased while PeT, PeM, and %Pe fell; these changes are considered desirable by producers and/or consumers. PuM was the variable that displayed more strong's association with other variables in the analysis.

Histopathological Features of Pendred Syndrome Thyroids Align with Differences in the Expression of Thyroid-Specific Markers, Apical Iodide Transporters, and Ciliogenesis Process.

Pendred syndrome (PDS) is an autosomal recessive disorder caused by mutations in the gene that encodes pendrin. Pendred thyroid tissue is supposedly altered by the absence of functional pendrin, but it is still unknown whether other iodide exchangers could compensate for the loss of the protein. Moreover, we have recently described that primary cilium, a conserved structure present at the apical surface of normal follicular cells, suffers different alterations in functional thyroid diseases. We aimed (1) to better understand the histopathological changes experienced by PDS thyroids, (2) to analyze the expression of different thyroid-specific genes and alternative iodide transporters and, finally, (3) to determine whether those changes may alter the morphological pattern of primary cilia in follicular cells. Thyroid samples from a series of four PDS patients were analyzed by immunohistochemistry, double immunofluorescence, and morphometry to evaluate changes in primary cilia frequency and length. We found thyroid follicular nodular disease in all PDS thyroids, frequently in association with follicular adenomas. There were only slight changes in the expression of thyroid-specific markers. Although no positivity for pendrin was found, cytoplasmic immunostaining for ANO-1, CLC-5, and CFTR was stronger in diffuse hyperplastic areas when compared to areas with highly cellular follicular nodules (HCFNs). HCFNs and follicular adenomas always showed diminished ciliary frequency and length. Our results suggest a direct relationship between the absence of functional pendrin and the loss of the normal thyroid architecture in PDS patients, which was also accompanied by differences in the expression of specific immunohistochemical markers and altered ciliogenesis. The present data may help the pathologist in screening for PDS.

[Analysis of brain complexity and mental disorders]. / Análisis de complejidad de la actividadcerebral y trastornos mentales.

The knowledge of the brain processes underlying mental disorders has significantly increased during the last decades, but in spite of this very important research effort a biological marker is not available for such disorders. For example, neurophysiological techniques (EEG and MEG),have been broadly utilized in the investigation of the most important psychiatric syndromes such as schizophrenia, major depression, bipolar disorder or obsessive/compulsive disorder. The outcomes of some of those neurophysiological studies allowed the building of statistical models with very high sensitivity and specificity, although those models did not reach day-to-day clinical practice. A potential explanation for this situation is an inadequate analysis procedure which might be missing some important quantums of information contained in brain signals. In this vein, new methods of non-linear analysis have been proposed for the investigation of neurophysiological data. Particularly, the analysis of brain signals' complexity has been broadly utilized in the investigation of psychiatric disorders. Parameters of EEG-MEG complexity usually estimate the predictability of brain oscillations and/or the number of independent oscillators underlying the observed signals. More importantly, complexity parameters seem to be sensitive to the temporal components of brain activity, and therefore might reflect the dynamical nature of psychiatric disorders. This paper reviews some of the most relevant studies within this field, especially those focusing on the diagnosis, follow-up and prediction of response to treatment.

Biomagnetic profiles of verbal memory success in patients with mesial temporal lobe epilepsy.

The risk of cognitive decline after mesial temporal lobe (MTL) resection in the dominant hemisphere for treatment of epilepsy has been assessed with the intracarotid amytal procedure and functional neuroimaging. In this study we used magnetoencephalography (MEG) to analyze memory profiles in patients with left hippocampal sclerosis (HS). Biomagnetic brain activity related to successful memory was compared in nine patients with left HS and nine age-matched controls. Patients manifested a higher number of activity sources over the right inferior parietal lobe in the late portion of the time window, and higher activity in the right than in the left MTL between 400 and 800 ms. This was reinforced by a -0.46 MTL laterality index, which indicates right MTL dominance. Controls showed a higher number of dipoles in the left anterior ventral prefrontal region, between 400 and 600 ms, and in the left MTL across the whole time window. Three patients who underwent a left temporal lobectomy, were seizure free, and who did not exhibit memory impairment after left temporal lobectomy, showed no activity in the left MTL presurgically. These results could support the ability of MEG to describe the time-modulated brain activity related to memory success in patients with epilepsy with left HS.

Increased biomagnetic activity in the ventral pathway in mild cognitive impairment.

OBJECTIVE: Mild cognitive impairment (MCI) patients represent an intermediary state between healthy aging and dementia. MCI activation profiles, recorded during a memory task, have been studied either through high spatial resolution or high temporal resolution techniques. However, little is known about the benefit of combining both dimensions. Here, we investigate, by means of magnetoencephalography (MEG), whether spatio-temporal profiles of neuromagnetic activity could differentiate between MCI and age-matched elderly participants. METHODS: Taking the advantage of the high temporal resolution and good spatial resolution of MEG, neuromagnetic activity from 15 elderly MCI patients and 20 age-matched controls was recorded during the performance of a modified version of the Sternberg paradigm. RESULTS: Behavioral performance was similar in both groups. A between group analysis revealed that MCI patients showed bilateral higher activity in the ventral pathway, in both the target and the non-target stimuli. A within-group analysis of the target stimuli, indicates a lack of asymmetry through all late latency windows in both groups. CONCLUSIONS: MCI patients showed a compensatory mechanism represented by an increased bilateral activity of the ventral pathway in order to achieve a behavioral performance similar to the control group. SIGNIFICANCE: This spatio-temporal pattern of activity could be another tool to differentiate between healthy aging and MCI patients.

Magnetoencephalographic pattern of epileptiform activity in children with early-onset autism spectrum disorders.

OBJECTIVE: To provide further data around magnetoencephalographic (MEG) findings in early-onset autism spectrum disorders (ASD). METHODS: Thirty-six children (mean age 7 years) diagnosed of PDD (DSM-IV, ICD-10) were studied. There were 22 children with autistic disorder, 9 with Asperger's syndrome, and 5 with pervasive developmental disorder not otherwise specified (PDD-NOS). According to the Childhood Autism Rating Scale (CARS), the autistic disorder was mild to moderate in 11, and severe in 11. Neuroimaging studies using three-dimensional MRI as well as simultaneous MEG-EEG and fusion techniques through magnetic source imaging (MSI) were performed, with the aid of anesthesia in non-cooperative patients. RESULTS: Most patients had no EEG abnormalities. All ASD children showed common specific abnormalities in the shape of low amplitude monophasic and biphasic spikes (isolated or short bursts) as well as acute waves, predominantly distributed in the perisylvian areas. In Asperger's syndrome, epileptiform spikes were mostly found in the right hemisphere. No lateralized epileptiform activity was observed in non-Asperger's autistic patients. CONCLUSIONS: MEG epileptiform activity is frequently documented in children with early-onset ASD. SIGNIFICANCE: Subclinical epileptiform activity is present especially in the perisylvian regions for many patients with ASD.

[Executive neurofunctionality: a comparative study in high intellectual abilities]. / Neurofuncionalidad ejecutiva: estudio comparativo en las altas capacidades.

INTRODUCTION: From a differential perspective, high intellectual ability is an expression of intellectual functioning with characteristic functional correlates and structural correlates of the underlying neural activity that suggests an improved executive capacity as a relevant characteristic, highlighting in it a more effective working memory. DEVELOPMENT: The neuroscientific evidences about the neural mechanisms that can explain the differences are analyzed between the intellectual functioning of the high intellectual ability and the typical intellectual capacity. The possibilities that offer the recording of evoked potentials to capture fundamental mental processes that allow explain the differences between them are put under review. CONCLUSIONS: Neuroscientific evidences through electroencephalography or other mental imagery techniques show that the brain, as a structural correlate of high intellectual abilities, has greater neural efficiency, interconnectivity and differences in the cytoarchitecture. It is a brain that captures, understands and interprets reality in a qualitatively different manner. But the neural differences are structural and the high intellectual capacity emerges from its plasticity functional. That is, it is a brain prepared for better executive regulation that is not always directly related with excellence and the eminent manifestation of its potentiality because it requires other conditioning factors such as motivation, the organization of knowledge, personal traits of temperament or perfectionism, and exogenous conditions.

TITLE: Neurofuncionalidad ejecutiva: estudio comparativo en las altas capacidades.Introduccion. Desde una perspectiva diferencial, la alta capacidad intelectual es una expresion del funcionamiento intelectual con unos correlatos funcionales caracteristicos y unos correlatos estructurales de la actividad neural subyacente que sugieren una capacidad ejecutiva mejorada como caracteristica relevante, destacando en ella una memoria de trabajo mas eficaz. Desarrollo. Se analizan las evidencias neurocientificas sobre los mecanismos neurales que pueden explicar las diferencias entre el funcionamiento intelectual de la alta capacidad intelectual y la capacidad intelectual tipica, y se revisan las posibilidades que ofrece el registro de potenciales evocados para apresar procesos mentales fundamentales que permitan explicar las diferencias entre ellas. Conclusiones. Las evidencias neurocientificas mediante electroencefalografia u otras tecnicas de imagineria mental muestran que el cerebro, como correlato estructural de la alta capacidad intelectual, tiene mayor eficiencia neural, interconectividad y diferencias en la citoarquitectura. Es un cerebro que captura, comprende e interpreta la realidad de forma cualitativamente diferente. Pero las diferencias neurales son estructurales y la alta capacidad intelectual emerge de su plasticidad funcional. Es decir, es un cerebro preparado para una mejor regulacion ejecutiva que no siempre guarda relacion directa con la excelencia y la eminente manifestacion de su potencialidad porque precisa de otros condicionantes como la motivacion, la organizacion del conocimiento, rasgos personales de temperamento o perfeccionismo, y condicionantes exogenos.

[Perisylvian magnetoencephalografic impairments in patients with autism spectrum disorders]. / Alteraciones magnetoencefalograficas perisilvianas en pacientes con trastornos del espectro autista.

INTRODUCTION: The perisylvian areas, located around the Sylvian fissure, are constituted by frontal, temporal and parietal brain regions. These are connected forming specialized neural networks and play a primary role in the development of linguistic skills and social cognition. These areas are a possible neuronal substrate of cognitive and behavioral impairments in patients with autism spectrum disorders (ASD). AIM: To locate and quantify epileptiform activity sources through magnetoencephalography in frontal perisylvian areas in children with idiopathic ASD. PATIENTS AND METHODS: Sixty-eight children with idiopathic ASD were studied by magnetoencephalography. The children were classified into two groups: a group of 41 children with autistic disorder and a combined group of 27 children with Asperger syndrome and children with pervasive developmental disorder not otherwise specified. The sources of magnetoencephalografic epileptiform activity detected in the frontal perisylvian were localized and quantified. RESULTS: The amount of epileptiform activity in frontal perisylvian region was significantly higher in children with autistic disorder. CONCLUSIONS: The amount of epileptiform activity in frontal perisylvian areas differed significantly between children with autistic disorder and those with Asperger syndrome and pervasive developmental disorder not otherwise specified.

TITLE: Alteraciones magnetoencefalograficas perisilvianas en pacientes con trastornos del espectro autista.Introduccion. Las areas perisilvianas se situan alrededor de la cisura de Silvio y estan constituidas por regiones cerebrales frontales, temporales y parietales. Estas regiones estan conectadas formando redes neurales especializadas y desempeñan una funcion elemental en el desarrollo de las habilidades linguisticas y de la cognicion social. Estas areas son un posible sustrato neural de las alteraciones cognitivas y conductuales en los pacientes con trastornos del espectro autista (TEA). Objetivo. Localizar y cuantificar las fuentes de actividad epileptiforme mediante magnetoencefalografia en areas frontales perisilvianas en niños con TEA primario. Pacientes y metodos. Se estudio a 68 niños con TEA idiopatico mediante magnetoencefalografia. Se clasificaron en dos grupos: uno de 41 niños con trastorno autista y un grupo combinado de 27 niños con sindrome de Asperger y niños con trastorno generalizado del desarrollo no especificado. Se localizaron y se cuantificaron las fuentes de actividad epileptiforme magnetoencefalografica detectadas en las areas frontales perisilvianas. Resultados. La actividad epileptiforme en la region perisilviana frontal fue significativamente mayor en el grupo de niños con trastorno autista. Conclusiones. La localizacion y cantidad de actividad epileptiforme en areas frontales perisilvianas difirieron significativamente entre los niños con trastorno autista y aquellos con sindrome de Asperger y trastorno generalizado del desarrollo no especificado.

Substance P and acetylcholine are co-localized in the pathway mediating mucociliary activity in Rana pipiens.

Mucociliary activity is an important clearance mechanism in the respiratory system of air breathing vertebrates. Substance P (SP) and acetylcholine play a key role in the stimulation of the mucociliary transport in the frog palate. In this study, retrograde neuronal tracing was combined with immunocytochemistry for SP and choline acetyl transferase (ChAT) in the trigeminal ganglion and for neurokinin-1 receptor (NK1R) in the palate of Rana pipiens. The cells of origin of the palatine nerve were identified in the trigeminal ganglion using the retrograde tracer Fluorogold (FG). Optimal labeling of FG cells in the trigeminal ganglion was obtained at 96 h of exposure. Immunoflorescent shows that SP and acetylcholine are co-localized in 92% of the cells labeled with FG in the trigeminal ganglion. NK1 receptors were found in the membrane of epithelial and goblet cells of the palate. Ultrastructural study of the palate showed axonal-like endings with vesicles in connection with epithelial and goblet cells. These results further support the concerted action of both neurotransmitters in the regulation of mucociliary activity in the frog palate.

Influence of milking method, disinfection and herd management practices on bulk tank milk somatic cell counts in tropical dairy herds in Colombia.

The aims of this study were to evaluate the effects of milking method, disinfection practices and other management factors on the bulk tank milk somatic cell count (BTSCC) in tropical dairy herds and to examine potential interactions with time. One hundred and thirty farms in the Northern region of Antioquia, Colombia, were visited once per month for 24 months. A two level linear mixed model for repeated measures was used to assess the impact on log transformed BTSCC (lnBTSCC). The geometric mean of the BTSCC for all herds was 262,330 cells/mL. The two-level linear mixed model showed that lnBTSCCs in hand milked herds were significantly higher than in machine milked herds. Fore-stripping corresponded with a 27% increase in lnBTSCC and failing to post-dip corresponded with a 45% increase in lnBTSCC. The two way interactions of sampling month with milking method, singeing udders and pre-dipping were significant. The lowest predicted lnBTSCC was observed in machine milked herds that practised both pre-dipping and singeing of udders. This study suggests that milking procedures and disinfection practices can interact with time and have substantial effects on lnBTSCC.

Medial temporal lobe neuromagnetic hypoactivation and risk for developing cognitive decline in elderly population: a 2-year follow-up study.

Cognition declines as a function of age. However, some elders could develop more severe status such as mild cognitive impairment (MCI). The aim of this study was the early detection of neurophysiological patterns of brain activity that may predict the possibility of certain subjects to develop MCI. Brain magnetic activity was recorded from 15 healthy subjects during a memory task by means of magnetoencephalography. None of the participants could be considered as MCI at the time of the first clinical evaluation. After 2-year follow-up, five subjects developed MCI and 10 maintained their cognitive status across time. The subjects who developed cognitive decline showed a lower number of activity sources in the left medial temporal lobe between 400 and 800 ms after stimulus onset, as compared to the non-cognitive decline group. These findings may help with the early identification of elderly subjects at high risk of cognitive decline, allowing the possibility of neuropsychological or pharmaceutical treatment that delay or prevent the progression of the cognitive impairment.

Paroxysmal MEG activity in obsessive compulsive patients without SSRIs therapy.

We describe a fronto-temporal paroxysmal rhythmic activity registered by magnetoencephalography (MEG) in two patients with obsessive compulsive disorder (OCD) without SSRIs treatment. The localization of the activity involves cingulate cortex and frontal areas. We think that these MEG findings are related to the disease itself, rather than representing pharmacological SSRIs effect.

[The effect of passive tactile stimulation in the brain activity of children with attention deficit]. / Efecto de la estimulacion tactil pasiva en la actividad cerebral de niños con deficit de atencion.

INTRODUCTION: The N200 and P300 evoked potentials have proved a useful tool in monitoring children with attention deficit disorder (ADD). AIM: To assess brain information processing by the N200 and P300 in touch modality in children with ADD. SUBJECTS AND METHODS: The P300 and N200 components to oddball tactile stimulation paradigm were recorded in an experimental group of 17 children with ADD at the beginning and the end of the daily training tactile stimulation, another 12 children with ADD and 21 control children without ADD who no received tactile stimulation. Three groups aged between 7 and 11 years. RESULTS: Results show a significant decrease in latency of N200 and P300 waves in the experimental group at the study end. N200 significant differences in the experimental group temporal parietal and occipital areas were found, while the differences in the P300 are located in postcentral and parietal areas. CONCLUSION: Systematic, orderly and organized tactile stimulation in children with ADD can be effective to improve N200-P300 latencies providing greater parietal brain plasticity, associated to perceptive attention.

TITLE: Efecto de la estimulacion tactil pasiva en la actividad cerebral de niños con deficit de atencion.Introduccion. Los potenciales evocados N200 y P300 han demostrado ser una herramienta de gran utilidad en el seguimiento de niños con trastorno por deficit de atencion (TDA). Objetivo. Evaluar el procesamiento cerebral de la informacion mediante los componentes N200 y P300 en modalidad tactil en niños con TDA. Sujetos y metodos. Se registraron los componentes N200 y P300 de los potenciales evocados durante una tarea oddball de estimulacion tactil en un grupo experimental de 17 niños con TDA al principio y al final de un entrenamiento mediante estimulacion tactil diaria, en otro de 12 niños con TDA y en 21 niños control sin TDA que no recibieron estimulacion tactil. Los tres grupos tenian edades comprendidas entre 7 y 11 años. Resultados. Los resultados indican una disminucion significativa de la latencia de las ondas N200 y P300 en el grupo experimental al final del estudio. Se encontraron diferencias significativas en la N200 en el grupo experimental en areas temporales parietales y occipitales, mientras que, en la P300, las diferencias se localizan en areas poscentrales y parietales. Conclusion. La estimulacion tactil de manera sistematica, ordenada y organizada en niños con TDA puede ser efectiva para la mejora de la latencia de los potenciales evocados N200 y P300, asi como para una mayor plasticidad cerebral parietal, asociada a la atencion perceptiva.

Noradrenaline transporter and its turnover rate are decreased in blood lymphocytes of patients with major depression.

Lymphocytes possess transporters of serotonin and dopamine, and also contain monoamines. The objective of this work was to determine the presence of noradrenaline transporters, the turnover rate of noradrenaline and serotonin in lymphocytes of major depression patients, and to correlate the biochemical parameters with the severity of the disorder. Lymphocytes from peripheral blood were isolated by Ficoll/Hypaque, and noradrenaline transporter was studied by binding of [3H]nisoxetine: control group (29, age 31.52+/-1.08, 7 men) and major depression patients (35, age 36.68+/-1.69, 6 men), Hospital Vargas de Caracas. Diagnostic was done by criteria of the American Psychiatric Association and severity by Hamilton Scale for Depression. Levels of noradrenaline, serotonin, 3-methoxy-4-hydroxyphenylglycol and 5-hydroxyindoleacetic acid were determined by HPLC. Turnover rate was evaluated by the ratios of monoamines and metabolites. Correlations were done between the biochemical parameters and the severity of depression. The score of Hamilton for Depression was 22.77+/-0.51. There was a reduction in the number of transporters in lymphocytes of patients, 0.95+/-0.27 versus 4.06+/-1.67 fmol/10(6) cells. Levels of monoamines and metabolites did not significantly differ between patients and controls. However, there was a higher monoamine/metabolite ratio in lymphocytes of patients, indicating a reduction of metabolic turnover rate. Also there was a relative greater concentration of noradrenaline than serotonin in the lymphocytes of the patients, as indicated by the ratio noradrenaline/serotonin. Noradrenergic and serotonergic turnover is decreased in blood peripheral lymphocytes of major depression patients; the reduction in noradrenaline transporter could be related to changes in intracellular levels, and these modifications could result in functional changes of the immune system.

[Frontal seizures recorded by magnetoencephalography. Case report]. / Crisis frontales registradas mediante magnetoencefalografía. Caso clínico.

INTRODUCTION: This paper reports the usefulness of magnetoencephalography (MEG) in the anatomical localization of the onset and spread of seizures. CASE REPORT: In a 34-year-old male patient who suffered from drug-resistant complex partial seizures (sometimes generalized) with loss of awareness, magnetic resonance imaging revealed a probable left frontobasal cortical dysplasia. Ictal scalp electroencephalogram showed left frontotemporal theta waves. Electrocorticography (ECoG) registered interictal polyspike discharges and located the seizure onset in the lateral orbital side of the left frontal lobe. Three seizures were registered by MEG, clinically similar to the ones usually experienced by the patient. MEG ictal spike dipole location showed seizure onset coming from the left inferior frontal gyrus (as the ECoG), spreading on to other frontal areas, insula and temporal lobe, all in the left hemisphere. CONCLUSION: MEG may be considered as a useful diagnosis modality in the study of partial seizure physiopathology as well as in its presurgical evaluation.

Bone mineral density reduction in adolescents with systemic erythematosus lupus: association with lack of vitamin D supplementation.

The aim of this study is to evaluate body composition and the bone mineral density in female adolescents with juvenile systemic lupus erythematosus. Body composition (BC) and bone mineral density (BMD) were evaluated in an observational cohort study with 35 postmenarcheal adolescent females. The variables studied were as follows: current and cumulative corticosteroid dose, intake of supplements containing calcium and vitamin D, 24-h proteinuria, body mass index (BMI), and height for age (Z-score). BC was assessed using dual-energy X-ray absorptiometry (DXA) at two time points (median interval of 1.2 years). The fat mass index (FMI = fat mass in kilograms divided by the height in meters squared) and lean mass index (LMI = lean mass in kilograms divided by the height in meters squared) were calculated based on the DXA results. BMD was classified according to the International Society of Clinical Densitometry (low BMD for chronological age < -2.0 standard deviations). .The mean age of the subjects was 15.4 ± 1.8 years. Of patients, 54.3 % were normal weight, 22.8 % were overweight, 22.8 % were obese, and 8.6 % had short stature. Low BMD for chronological age was observed in 42.8 % of patients, and 60 % were not taking vitamin D. There was no significant difference between the two time points with respect to FMI, LMI, or body mass index Z-score (ZBMI); however, BMD has decreased significantly (p = 0.011). There was an association between not taking a vitamin D supplement and decreased BMD (p = 0.027). Almost half of the patients had altered nutritional status. The BMD decrease in adolescents with juvenile systemic lupus erythematosus (JSLE) was associated with the lack of vitamin D supplementation, highlighting the importance of well-defined vitamin D supplementation protocols.

Plasma total homocysteine levels and the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene: a study in an Italian population with dementia.

Hyperhomocysteinemia is a known risk factor for vascular disease and commonly occurs in the elderly. Several studies have shown an association between elevated plasma homocysteine levels and cognitive impairment, indicating that it may play a role in the pathophysiology of dementia. We studied plasma homocysteine, folate, vitamin B12 levels and the MTHFR C677T genotype in an Italian population of patients with dementia. We confirmed that elevated plasma tHcy (>14 micromol/l) is common in elderly subjects with dementia. Although we found a high prevalence of the MTHFR TT genotype (21.2%) the allele frequency is not over-represented relative to the control population. We also observed a high incidence of folate deficiency (38%) in subjects with dementia. Elevated homocysteine was associated with low plasma folate (<5.7 nmol/l) and the MTHFR TT genotype. Moderate to severe hyperhomocysteinemia (>26.1 nmol/l) was associated with a significantly lower MMSE score. Hyperhomocysteinemia may be neurotoxic by several different mechanisms affecting cognitive function. Further studies are needed to fully explore the potential of B vitamin supplementation to lower plasma homocysteine and improve cognitive function.

Expectancy and response strategy to sensory stimuli.

We investigated the relationship between sensory discrimination and the selection of appropriate responses in subjects performing two different reaction-time tasks, in which three auditory stimuli were presented in random order and with a different likelihood of occurrence. Subjects anticipated the need to make different responses based on the likelihood that a particular stimulus would occur on a particular trial. This was determined by the occurrence and distribution of premovement potentials prior to the stimulus, which were consistent with preparation to respond to the most frequently occurring stimulus. These anticipatory cerebral events, however, could be altered after recognition that this frequent stimulus had not occurred. Thus, after the occurrence of a stimulus other than the anticipated frequent tone, the scalp distribution of cerebral potentials changed in a manner suggesting that the next most frequently occurring stimulus was anticipated. Nonetheless, subjects were able to respond to the least probable stimulus both accurately and rapidly despite a failure to anticipate it correctly, as judged by the cerebral "lateralized readiness potential." These results indicate that stimulus evaluation and response selection are integrated and dynamic cerebral processes, and raise doubt about the functional significance of the so-called premovement readiness potential.

Cortical organization for receptive language functions in Chinese, English, and Spanish: a cross-linguistic MEG study.

Chinese differs from Indo-European languages in both its written and spoken forms. Being a tonal language, tones convey lexically meaningful information. The current study examines patterns of neurophysiological activity in temporal and temporoparietal brain areas as speakers of two Indo-European languages (Spanish and English) and speakers of Mandarin-Chinese were engaged in a spoken-word recognition task that is used clinically for the presurgical determination of hemispheric dominace for receptive language functions. Brain magnetic activation profiles were obtained from 92 healthy adult volunteers: 30 monolingual native speakers of Mandarin-Chinese, 20 Spanish-speaking, and 42 native speakers of American English. Activation scans were acquired in two different whole-head MEG systems using identical testing methods. Results indicate that (a) the degree of hemispheric asymmetry in the duration of neurophysiological activity in temporal and temporoparietal regions was reduced in the Chinese group, (b) the proportion of individuals who showed bilaterally symmetric activation was significantly higher in this group, and (c) group differences in functional hemispheric asymmetry were first noted after the initial sensory processing of the word stimuli. Furthermore, group differences in the degree of hemispheric asymmetry were primarily due to greater degree of activation in the right temporoparietal region in the Chinese group, suggesting increased participation of this region in the spoken word recognition in Mandarin-Chinese.