Early detection of Parkinson's disease: Systematic analysis of the influence of the eyes on quantitative biomarkers in resting state electroencephalography.

While resting state electroencephalography (EEG) provides relevant information on pathological changes in Parkinson's disease, most studies focus on the eyes-closed EEG biomarkers. Recent evidence has shown that both eyes-open EEG and reactivity to eyes-opening can also differentiate Parkinson's disease from healthy aging, but no consensus has been reached on a discriminatory capability benchmark. The aim of this study was to determine the resting-state EEG biomarkers suitable for real-time application that can differentiate Parkinson's patients from healthy subjects under both eyes closed and open. For this, we analysed and compared the quantitative EEG analyses of 13 early-stage cognitively normal Parkinson's patients with an age and sex-matched healthy group. We found that Parkinson's disease exhibited abnormal excessive theta activity in eyes-closed, which was reflected by a significantly higher relative theta power, a higher time percentage with a frequency peak in the theta band and a reduced alpha/theta ratio, while Parkinson's patients showed a significantly steeper non-oscillatory spectral slope activity than that of healthy subjects. We also found considerably less alpha and beta reactivity to eyes-opening in Parkinson's disease plus a significant moderate correlation between these EEG-biomarkers and the MDS-UPDRS score, used to assesses the clinical symptoms of Parkinson's Disease. Both EEG recordings with the eyes open and reactivity to eyes-opening provided additional information to the eyes-closed condition. We thus strongly recommend that both eyes open and closed be used in clinical practice recording protocols to promote EEG as a complementary non-invasive screening method for the early detection of Parkinson's disease, which would allow clinicians to design patient-oriented treatment and improve the patient's quality of life.

Statistical geometric affinity in human brain electric activity.

The representation of the human electroencephalogram (EEG) records by neurophysiologists demands standardized time-amplitude scales for their correct conventional interpretation. In a suite of graphical experiments involving scaling affine transformations we have been able to convert electroencephalogram samples corresponding to any particular sleep phase and relaxed wakefulness into each other. We propound a statistical explanation for that finding in terms of data collapse. As a sequel, we determine characteristic time and amplitude scales and outline a possible physical interpretation. An analysis for characteristic times based on lacunarity is also carried out as well as a study of the synchrony between left and right EEG channels.

[Characteristic times in sleep-waking electroencephalograms]. / Tiempos caracterísiticos en electroencefalogramas de sueño/vigilia.

INTRODUCTION AND AIMS: EEG signals emerge from the collective behaviour of large neuronal aggregates and betrays the information processed by neocortex. This electrophysiological collective activity varies with the brain function. Thus, one can ask whether there exists any indication of that neuronal activity in the EEG record. In this work this question is considered in the particular case of sleep/awake EEG s. To this aim, the concept of lacunarity is proposed as a tool to analyse the texture of the EEG samples. From the resulting lacunarity profiles an index is defined which represents a characteristic time of each phase. PATIENTS AND METHODS: The samples analysed corresponds to 30 seconds epochs from polysomnographic night records. Essential details for the computation of lacunarity patterns and the propounded index are given. The mean values of characteristic times (in seconds) are: 0.43 (phase I); 0.73 (phase II); 1.12 (phase III/IV); 0.65 (REM); 0.12 (relaxed wakefulness). RESULTS AND CONCLUSIONS: With this criterium, the awake state is clearly distinguished from phase I and REM sleep, whereas REM sleep comes out to be similar to phase II. Finally, statistical analysis of results suggests the possibility to interpret this index as a complementary tool for reading polysomnographies as well as its application to different physiological or pathological situations of EEG records.

Tiempos característicos en electroencefalogramas de sueño/vigilia / Characteristic times in sleep-waking electroencephalograms

Introduction y objetivos. La señal EEG es el resultado del comportamiento medio de grandes poblaciones de neuronas agregadas y, por tanto, refleja en gran medida la información procesada en el neocórtex. Esta actividad electrofisiológica colectiva será diferente para las distintas funciones cerebrales. Cabe, pues, plantear la siguiente pregunta: ¿Existe en los trazados EEG alguna indicación que pueda cuantificarse de aquella actividad neuronal colectiva? Esta es la cuestión que abordamos en el presente trabajo, y nos limitamos a registros EEG de sueño y vigilia en estado de relajación mental. Proponemos aplicar a estos EEG el concepto de lagunaridad como un método para analizar la textura de las muestras. A partir de los patrones obtenidos, definimos un índice que representa un tiempo característico de cada fase. Pacientes y métodos. Las muestras analizadas corresponden a fragmentos de 30 segundos obtenidos durante registros polisomnográficos nocturnos. Los detalles esenciales para el cálculo de los patrones de lagunaridad y del índice propuesto se describen en el texto. Estos tiempos característicos toman los siguientes valores (en segundos): 0,43 (fase-I); 0,73 (fase-II); 1,12 (fase-III/IV); 0,65 (REM); 0,12 (vigilia en relajación mental). Resultados y conclusiones. Con este criterio, la vigilia se diferencia claramente de la fase-I (somnolencia) y del sueño paradójico (REM). A su vez, el sueño REM resulta ser semejante a la fase-II y claramente distinto de la fase-I. Finalmente, sobre la base del análisis estadístico de los resultados, se apunta la posibilidad de incorporar este índice como un elemento de ayuda adicional en la lectura de polisomnografías, o su aplicación a diferentes situaciones fisiológicas o incluso patológicas del registro EEG (AU)

Growth phenotype of cultured skin fibroblasts from IDDM patients with and without nephropathy and overactivity of the Na+/H+ antiporter.

An increased activity of the Na+/H+ antiporter in cells from patients with insulin-dependent diabetes mellitus (IDDM) has been proposed as a potential marker of nephropathy. We evaluated Na+/H+ antiporter activity and its relationship to DNA and protein synthesis in cultured skin fibroblasts from patients with IDDM classified as having either overt nephropathy or absence of nephropathy on the basis of urinary albumin excretion and kidney biopsy findings. In IDDM patients with overt nephropathy, Na+/H+ antiporter activity in serum stimulated cells was increased as compared to cells from control subjects (9.62 +/- 0.89 vs. 5.67 +/- 0.97 mmol H+/min, P < 0.005, respectively) and cells from IDDM patients without nephropathy (7.22 +/- 0.67 mmol H+/min, P < 0.025). By contrast, in cells made quiescent by serum deprivation Na+/H+ antiporter activity was lower than in serum-stimulated cells and there were no significant differences between the three groups. DNA synthesis assessed by [3H] thymidine incorporation was increased in the IDDM group with nephropathy as compared to the group without nephropathy (138 +/- 14 vs. 105 +/- 13 cpm/1000 cells, respectively, P < 0.05) and as compared to control subjects (65 +/- 11 cpm/1000 cells, P < 0.001). By contrast, protein synthesis assessed by [14C] L-leucine incorporation was not increased in fibroblasts from IDDM patients with nephropathy, suggesting that cellular hypertrophy is not a feature of their altered growth phenotype. After chronic inhibition of the Na+/H+ antiporter using EIPA (25 microM), [3H] thymidine incorporation was reduced by about 20% both in cells from IDDM patients and controls. This parameter therefore remained higher in cells from IDDM patients with nephropathy than in those from controls (81 +/- 16 vs. 40 +/- 6 cpm/1000 cells, P < 0.05), while in cells from IDDM patients without nephropathy [3H] thymidine incorporation after EIPA (56 +/- 7.0 cpm/1000 cells) was intermediate between cells from controls and IDDM patients with nephropathy. We argue that cultured skin fibroblasts from IDDM patients, with nephropathy display an abnormal growth phenotype characterized by cell hyperplasia. This growth phenotype is associated with overactivity of the Na+/H+ antiporter during serum stimulation but not when cells are made quiescent and persists after inhibition of the Na+/H+ antiporter. Our data, therefore, further shows that overactivity of the Na+/H+ antiporter is not required for the expression of the altered growth phenotype of cultured skin fibroblasts from IDDM patients with nephropathy.

Altered blood pressure during sleep in normotensive subjects with type I diabetes.

This study was designed to examine the circadian pattern of blood pressure in children and young adults with type I diabetes who were completely normotensive by standard criteria. Forty-five patients and the same number of age- and sex-matched control subjects were studied. In diabetic children of 10-14 years of age, the nocturnal fall in systolic and diastolic blood pressures was intact. In diabetics of 15-20 years of age, the fall in systolic blood pressure was blunted; in diabetics of 21-37 years of age, the fall in both systolic and diastolic blood pressures during sleep was blunted. When data from all diabetic subjects were pooled and analyzed in a multiple linear regression model, mean blood pressure during sleep correlated best with urinary albumin excretion (r = 0.60). On the basis of this finding, we subdivided our patients into two groups: a microalbuminuric group (urinary albumin excretion > 30 mg per 24 hours; mean, 160.3 +/- 29.7; n = 11) and a normoalbuminuric group (urinary albumin excretion < 30 mg per 24 hours; mean, 6.6 +/- 6.5; n = 34). Both systolic and diastolic blood pressures during sleep were higher in microalbuminuric (121.1 +/- 3.3 and 69.3 +/- 2.5 mm Hg, respectively) than in normoalbuminuric diabetics (114.2 +/- 1.8 and 60.1 +/- 1.2 mm Hg, p < 0.05) or control subjects (113.3 +/- 1.2 and 60.1 +/- 1.2 mm Hg, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Shunt nephritis: a report on five children.

Of 5 children with glomerulonephritis with infected ventriculoatrial shunt, 3 had improved renal function after antibiotic therapy and removal of the infected shunt. 1 patient with endoextracapillary proliferative glomerulonephritis with 70% glomerular crescents developed a rapidly progressive renal insufficiency. Renal failure was successfully managed by hemodialysis and kidney transplantation. 1 patient died from extrarenal causes in the course of a septic episode.

[Shunt nephritis (author's transl)]. / Nefritis de "shunt".

Five patients aged 1.1 - 4.3 years, affected by nephritis secondary to infection of ventriculo-atrial shunt are presented. The time lag between the occurrence of shunt infection and diagnosis of nephropathy varied from 1 to 12 months. In four patients "Staphylococcus epidermidis" was isolated from blood and CSF cultures, and "Staphylococcus aureus" in another one. Renal lesion presented as hematuria and proteinuria, and two patients developed a nephrotic syndrome. Hypertension was present in three patients. C'2 and D'4 hypocomplementemia was a constant feature in the acute stage of the disease. Endocapillary glomerulonephritis was observed in three patients and endo-extracapillary glomerulonephritis in one (70% of crescent formations). After shunt removal and antibiotic administration a favorable clinical course was followed in three patients, with remission of nephropathy signs. The fifth patient (non biopsied) died in the course of a septic process, having kept until then a good renal function.

[Renal transplantation in children: preliminary report (author's transl)]. / Trasplante renal pediátrico. Resultados preliminares.

The preliminary results of a pediatric renal transplantation program started two years ago are presented. Fourteen children aged four to 13 years received a renal transplantation from April 1979 through March 1981. In eight patients renal graft was obtained from a living related donor (father-mother) and six from corpse donor. Recipients body weight ranged from 11 to 40 kg. (mean, 25 kg.). The previous time on hemodialysis was between three and 13 months (mean, seven months). In all cases a transfusion protocol prior to renal transplantation was followed (five transfusions minimum). Donor-recipient compatibility ranged zero-three HLA compatibilities. The patients were coordinately managed by pediatric specialists. The follow-up of the transplanted children ranges from one to 24 months (mean, 10 months). All of the patients are alive and the graft is functioning in all but one. A chronic rejection episode begun five months after renal-transplantation caused in one patients a graft loss. Plasma creatinine is lesser than 1.50 mg/100 ml. in 11 cases and inferior to 2 mg./100 ml. in the other two patients. The non-immunological complications presented have been unremarkable and no repercussions on the patients evolution have been detected. Even though the follow-up period is short, the results are highly encouraging, supporting that renal transplantation is the election treatment in children with terminal renal failure.

[Incidence of renal involvement in Schönlein-Henoch syndrome (author's transl)]. / Incidencia de nefropatía en el síndrome de Schönlein-Henoch.

To determine the incidence of renal involvement in Schönlein-Henoch syndrome, authors enrolled in a prospective study all children admitted with this diagnoses from 1971 through 1978. They followed-up 112 patients, which represented the 2 per one thousand of the total hospital pediatric admission in the same period; 22 patients (19.6%) developed renal involvement. After two years of follow-up they observe one patient with progressive renal failure, four with minor urinary abnormalities and 17 asymptomatics. The single patient with renal failure represents the 4.5% of the patients with Schönlein-Henoch nephropathy and the 0.9% of the total affected with this syndrome.