Biomedical subjects

A R Vaz

Publications and source records attributed to A R Vaz.

6 recordsLinked to original sources

PubMed1998

Antibody avidity as a surrogate marker of successful priming by Haemophilus influenzae type b conjugate vaccines following infant immunization.

Evaluation of the new generation of conjugate vaccines is hampered by the absence of reliable surrogate markers of immunologic memory. Memory responses are characterized by rapid production of relatively high-avidity antibody; thus, a solid-phase ELISA was adapted for the measurement of anti-Haemophilus influenzae type b (Hib) IgG avidity. In a cohort of infants vaccinated at 2, 3, and 4 months of age with Hib conjugate vaccines, avidity increased in the period following vaccination, while antibody titer fell. After a booster dose at 1 year of age, both antibody titer and avidity increased. In a cohort with anti-Hib IgG <1.0 microg/mL following primary immunization, antibody avidity after booster was low, indicating an absence of priming. Antibody avidity may help distinguish, in persons with low antibody titers, between those who are primed for memory and those who are not.

Antibodies, Bacterial↗

PubMed1992

Posttraumatic epilepsy in civilians: clinical and electroencephalographic studies.

Posttraumatic epilepsy (PTE) is a known consequence of head trauma. The factors involved in posttraumatic seizures generation and the relationship between acute seizures and posttraumatic epilepsy are not without controversy. This also applies to the evolution of the electroencephalographic characteristics. The study here reported was performed analysing data from patients with posttraumatic epilepsy (N = 205) and data from patients followed-up since trauma and considered as a high risk population for the development of PTE (patients with acute seizures and/or patients with focal lesions--contusion, haematomas or penetrating head injury) (N = 152). Seizure type was associated with age and trauma severity (children, elderly and worst trauma cases present with a higher proportion of partial seizures). Neurological deficit and lesion location were associated with the seizure occurrence. The increased incidence of seizures was found when the most diffused brain dysfunction was combined with neurological deficits. The analysis of sequential EEGs performed at first, at 6th and 12 months post trauma revealed a non-stationary pattern throughout these time periods with EEG focal abnormalities remaining frequent for more than two years after the trauma. Children and old people have a higher proportion of EEG abnormalities with more frequent abnormal generalized activity in children and more frequent abnormal focal EEG activity in the elderly.

Adult↗

PubMed1990

Controversies in posttraumatic epilepsy.

In civilian accidents the factors involved in the origin of posttraumatic epilepsy are controversial. In this study of 506 consecutive head trauma patients and 101 epileptic patients developing seizures after head trauma, we have examined the importance of the duration of coma, type of seizure and drug therapy, time to first seizure, age and focal lesions and compared our results with the literature. The importance is stressed of focal lesions and of neurological deficits for the origin of posttraumatic seizures.

Adolescent↗

PubMedDate not supplied

Migraine and intracranial vascular malformations.

The relationships between migraine and A-V Malformations is a subject of controversy and the arguments are mainly based on case reports and retrospective data. To clarify this subject a structured inquiry and classification of headaches in large samples of patients with intracranial vascular malformations (IVM) is essential. The authors studied the prevalence of headaches in 51 patients with IVM admitted to our Department, between 1984 and 1992. The methods used were a review of medical records followed by a self-administered headache questionnaire and clinical interview using the IHS criteria for the diagnostic classification of headaches. The relative frequency of the different types of headaches was calculated and compared with the general population data. A correlative study of the headache characteristics with the type and location of the IVM was made. A high prevalence (47%) of migraine type headaches and a strong positive correlation (88.8%) between the site of AVM and side of the pain was found. This is highly suggestive but not conclusive of a pathophysiologic relationship between these entities. The conclusion drawn is that a prospective study of headaches by questionnaire or semi-structured clinical interview in patients with IVM is essential to discover the effective prevalence and characteristics of headaches associated with IVM and their relationships.

Adolescent↗

PubMedDate not supplied

[Atypical meningioma].

One case of intradiploic meningioma, causing partial occlusion of the superior longitudinal sinus, with subsequent visual trouble and another of lipomatous meningioma with great fat content and very calcified, that was found in a LCR fistula study of the cranial anterior stage, are described by the authors as atypical meningiomas.

Female↗

PubMedDate not supplied

[Dementia as a result of dural vascular malformation].

A case of dementia can result from encephalopathy caused by venous hypertension, produced by a dural vascular malformation (DVM). The authors describe one tentorial DVM with sinusal venous drainage and retrograde reflux to the cerebral veins (type II), that originated a leukoencephalopathy, and a progressive demential symptomatology. This demential status partially regressed after surgical treatment.

Aged↗