Persistent hepatitis A infection: case report.

Hepatitis A viral infection resolves completely within six months in all patients infected. The case presented is a rare one that took fifteen months to resolve from hepatitis A viral infection.

A population-based study of large granular lymphocyte leukemia.

Large granular lymphocyte (LGL) leukemia is a lymphoproliferative disorder of cytotoxic cells. T-cell LGL (T-LGL) leukemia is characterized by accumulation of cytotoxic T cells in blood and infiltration of the bone marrow, liver or spleen. Population-based studies have not been reported in LGL leukemia. We present clinical characteristics, natural history and risk factors for poor survival in patients with LGL leukemia using the Surveillance, Epidemiology, and End Results Program (SEER) and the United States National Cancer Data Base (NCDB). LGL leukemia is an extremely rare disease with the incidence of 0.2 cases per 1 000 000 individuals. The median age at diagnosis was 66.5 years with females likely to be diagnosed at 3 years earlier compared with males. Analysis of patient-level data using NCDB (n=978) showed that 45% patients with T-LGL leukemia required some form of systemic treatment at the time of diagnosis. T-LGL leukemia patients have reduced survival compared with general population, with a median overall survival of 9 years. Multivariate analysis showed that age >60 years at the time of diagnosis and the presence of significant comorbidities were independent predictors of poor survival.

Identification of a putative structural gene for cathepsin D in Caenorhabditis elegans.

Mutants of Caenorhabditis elegans having about 10% of wild-type activity of the aspartyl protease cathepsin D have been isolated by screening. Mutant homozygotes have normal growth rates and no obvious morphological or developmental abnormalities. The mutant gene (cad-1) has been mapped to the right extremity of linkage group II. Heterozygous animals (cad-1/+) show intermediate enzyme levels and animals heterozygous for chromosomal deficiencies of the right extremity of linkage group II have 50% of wild-type activity. Cathepsin D purified from a mutant strain has a lower activity per unit mass of pure enzyme. These data suggest that cad-1 is a structural gene for cathepsin D.

Neuronal effects of experimentally induced hydrocephalus in newborn rats.

To determine the effects of increased cerebrospinal fluid (CSF) pressure on neuronal morphology, obstructive hydrocephalus was induced by injecting kaolin into the fourth ventricle and cisterna magna of 1-day-old rats. The animals were sacrificed 10 to 12 days later, at which time severe ventriculomegaly and cortical thinning were apparent in the parieto-occipital region. Tissue from this area was processed by rapid Golgi methods. Well impregnated pyramidal neurons were examined by light microscopy, and their somatic and dendritic features compared to those of age-matched littermate controls. The somata of medium pyramidal neurons were unaffected, but their basilar dendrites had fewer branches and those that remained were shorter. A variable reduction in dendritic spines occurred, such that some branches were totally denuded while others exhibited spine densities similar to those seen in control animals. The most striking alteration was the occurrence of frequent dendritic varicosities. These enlargements of the dendritic shaft separated by extremely thin constrictions gave the affected segment a beaded appearance. Both dendritic spine loss and varicosity formation were most notable on distal portions of individual branches and within regions of the dendritic tree closest to the ventricular and meningeal surfaces. These alterations are consistent with other reports of dendritic changes associated with aging, mental retardation, and alcohol exposure. These observations suggest that hydrocephalus causes dendritic deterioration or retardation of dendritic maturation. The fact that neuronal morphology was not more severely affected may indicate that these effects are reversible.

Physicochemical determinants of drug diffusion across the conjunctiva, sclera, and cornea.

This investigation examined some of the barrier properties of the conjunctival, scleral, and corneal membranes. The diffusion of nadolol, timolol, propranolol, penbutolol, sucrose, and inulin was measured across the isolated corneal and scleral membranes of the rabbit using a two-chamber glass diffusion cell. Drug absorption across the cornea and the conjunctiva was studied in vivo by measuring precorneal drug clearance. The drug samples were analyzed either by HPLC or liquid scintillation counting (LSC). For all the compounds tested, the scleral permeability was significantly higher than the respective corneal permeability. The permeability coefficients of the beta-blockers varied in the following manner: propranolol > penbutolol > timolol > nadolol for the cornea, and penbutolol > propranolol > timolol > nadolol for the sclera. The cornea offered substantially more resistance to inulin, a polar, macromolecular substance, than did the conjunctiva. However, the cornea and conjunctiva offered comparable resistance to the smaller and less polar drug timolol. This information may serve as a basis for optimizing the intraocular delivery of drugs that are poorly absorbed across the cornea due to their physicochemical properties.

Intracerebral hemorrhage due to cerebral arteriovenous malformations.

The most common presentation of a pial arteriovenous malformation (AVM) is spontaneous intracerebral hemorrhage (ICH). The peak incidence of ICH is early in the third decade of life. This article discusses the management of ICH of unknown etiology, ICH from angiographically visible AVM, and ICH from angiographically occult vascular malformations based on the current understanding of the natural history of these disease entities.

Pediatric skull, skull base, and meningeal tumors.

Calvarial neoplastic and non-neoplastic tumors are routinely encountered by all neurosurgeons. Benign and malignant skull base and meningeal tumors are relatively rare lesions in children. Interdisciplinary approaches to those tumors more frequently encountered in the pediatric population in these locations are discussed. Unique aspects of the diagnosis, treatment, and prognosis for infants and children are discussed.

Indications for treatment of symptomatic atherosclerotic carotid artery disease.

Although the incidence of stroke and stroke mortality have declined during the past few decades, stroke still ranks third as a cause of death and a primary cause of long-term disability in most industrialized societies. Atherosclerotic disease at the carotid bifurcation accounts for approximately 20% to 30% of all ischemic strokes. In this article, the indications for treatment of symptomatic internal carotid artery stenosis are reviewed.

Radiographic incidence of multicentric malignant gliomas.

BACKGROUND: Multicentric malignant gliomas are interesting yet uncommon clinical entities with an unknown rate of occurrence. METHODS: We reviewed the computed tomography (CT) and magnetic resonance (MR) images of 100 consecutive patients with malignant gliomas to determine the incidence of multicentricity in malignant glial neoplasms. RESULTS: Five patients had multiple lesions on their initial radiographic study (synchronous lesions) and in four patients multiplicity developed after initial diagnosis (metachronous lesions). MR imaging demonstrated one lesion not seen on CT. CONCLUSIONS: Because synchronous or metachronous multicentricity was found in 9% of patients with malignant gliomas, treatment delivery should not be based on radiographic imaging without attempting to obtain an accurate diagnosis of the ongoing intracranial process.

The effect of written advice on preoperative cigarette consumption.

Two groups, each of 100 smokers, were compared in terms of reduction in cigarette consumption in the 5 days prior to elective surgery. One group was admitted to hospital in the routine way and information on preoperative cigarette consumption obtained by questioning each patient after recovery from anaesthesia. In the second group, a letter strongly advising the patient to stop smoking for 5 days preoperatively was enclosed with the admission letter. A proforma to record the daily cigarette consumption was also enclosed. By the day before surgery the mean cigarette consumption had fallen to 52% in Group I and 16% in Group II and 14 and 46 patients respectively had then stopped smoking completely. The differences were highly significant (P less than 0.001).