Ethanol's effects on auditory thresholds and reaction times during the acquisition of chronic ethanol self-administration in baboons

Baboons were trained to ingest ethanol at successively higher ethanol concentrations using oral self-administration techniques. Concurrently, animal psychophysical procedures were employed to determine auditory thresholds and reaction times daily. Maximal consumption of ethanol occurred at concentrations of 6-8% (w/v). During the initial period of ethanol self-administration, both auditory reaction times and auditory thresholds became elevated as animals consumed larger amounts of ethanol. For both the threshold and reaction time measures, the degree of elevation was correlated with the amount of ethanol consumed. These correlations decreased, however, with continued ethanol consumption. The elevations in sensory and motor function recovered to near-baseline levels when ethanol was no longer available.     

Dynamic spin-echo MRI of liver cancer using Gadolinium-DTPA: animal investigation

An animal model of liver cancer was used to demonstrate that with a fast MRI technique, Gadolinium-DTPA increases tumor-liver contrast. A spin-echo pulse sequence with short repetition (TR) and echo-delay (TE) times (TR 250/TE 15/Excitations 1) has a scan time of 0.6 min, which allows early dynamic postcontrast infusion imaging. This is necessary to capture peak compartmental differences when an extracellular contrast agent such as Gadolinium-DTPA is used. This short TR/short TE pulse sequence also increases T1-dependent tissue contrast over the traditional (inversion recovery or spin echo) T1-weighted pulse sequences. Our studies suggest a significant potential for improved detection of liver metastases with Gadolinium-DTPA-enhanced liver MRI.     

Is early onset cerebellar ataxia with retained tendon reflexes identifiable by electrophysiologic and histologic profile? A comparison with Friedreich's ataxia.

An electrophysiologic and histologic study was performed on 18 patients affected by early onset cerebellar ataxia with retained tendon reflexes (EOCA). Sensory and motor conduction velocity (SCV, MCV) was measured along peripheral nerves in all patients, somatosensory (SSEP) and brainstem auditory evoked potentials (BAEP) were recorded in 13; cortical stimulation (CS) in 12, and sural nerve biopsy in 4 patients were also performed. The results as a whole allow a division of EOCA patients into 2 groups: with (7 patients) and without (11 patients) peripheral neuropathy. Among EOCA patients with neuropathy a differential diagnosis with Friedreich's disease patients was not possible according to BAEPs and CS, while SSEPs could differentiate 2 out 5 patients in whom they were performed.     

Forthcoming meetings & events

Forthcoming meetings &; events     

Gaucher disease: abdominal MR imaging findings in 46 patients.

Abdominal magnetic resonance imaging findings were reviewed in 46 patients with Gaucher disease. All patients had hepatosplenomegaly at the time of initial imaging. Splenic nodules were present in 14 patients (30%) and varied in signal intensity. These nodules were isointense on T1-weighted and hypointense on T2-weighted images. Splenic infarcts were seen in 15 patients (33%), and four of these patients (9%) also had subcapsular fluid collections. Both nodules and infarcts were present in the spleen in four patients (9%). Pathologic correlation was performed with specimens from two patients who underwent partial splenectomy. Focal areas of abnormal signal intensity were noted in the liver in nine patients (20%). They were either stellate or segmental, and may represent fibrotic septa with ischemic changes associated with aggregates of Gaucher cells. No changes were noted in the kidneys or abdominal lymph nodes.     

Nephrotic syndrome and renal failure associated with a novel glycolipid storage disorder

A 57-year-old Caucasian male presented with severe nephrotic syndrome and diffuse organomegaly; he subsequently developed renal failure and died. Intracellular, crystalloid material was identified by light and electron microscopy in bone marrow, liver, spleen, mesenteric lymph nodes, and kidneys. Tissue extraction analysis identified the material as glucocerebroside and its immediate precursor, ceramide lactoside. Although Gaucher's disease cannot be completely excluded, glycolipid profiles do not conform to those of known storage disorders. Additionally, electron-microscopic studies indicate that the structural features of the glycolipid deposits are different from those of previously described storage diseases. These findings suggest a unique crystalloid deposition as the probable cause of a multisystem process, which was associated with renal insufficiency and death.     

Nursing grand rounds: multiple sclerosis.

Multiple sclerosis (MS) is a highly variable, unpredictable disease and one of the most life-altering diagnoses a person can receive. Because it usually strikes in the prime of life, frequently progresses to disability, and has no cure, MS can make a strong emotional impact--not only on those who suffer from it, but also the healthcare team. Because MS is such a complex, multifaceted disorder, nurses who care for people with MS are faced with numerous clinical challenges. Many of the challenges are unique to MS, demanding, and time-consuming. Well-informed nurses are positioned to evaluate and explain the disease process, assist in the alleviation of symptoms, educate partners and families, and help improve quality of life. A case example can help nurses understand the real-life concerns of a person with MS.     

Shape of the myopic eye as seen with high-resolution magnetic resonance imaging.

We have obtained multislice magnetic resonance (MR) images of the eye and calculated ocular dimensions along the three cardinal axes: antero-posterior (A-P), equatorial, and vertical. We found no difference in the shape of hyperopic (average refractive error: +3.72 D) and emmetropic eyes, both of which had an equatorial diameter longer than the A-P and vertical diameters. Myopic eyes (average refractive error: -6.54 D) were larger than hyperopic eyes, and most had the same spheroelliptical shape as that of the emmetropic and hyperopic eyes. The results suggest that during myopic progression an overall enlargement or a radial volume expansion has occurred.     

Molecular basis of essential fructosuria: molecular cloning and mutational analysis of human ketohexokinase (fructokinase)

Essential fructosuria is one of the oldest known inborn errorsof metabolism. It is a benign condition which is believed toresult from deficiency of hepatic fructokinase (ketohexokinase,KHK, E.C.2.7.1.3). This enzyme catalyses the first step of metabolismof dietary fructose, conversion of fructose to fructose-1-phosphate.Despite the early recognition of this disorder, the primarystructure of human KHK and the molecular basis of essentialfructosuria have not been previously defined. In this report,the isolation and sequencing of full-length cDNA clones encodinghuman ketohexokinase are described. Alternative mRNA speciesand alternative KHK isozymes are produced by alternative polyadenylationand splicing of the KHK gene. The KHK proteins show a high levelof sequence conservation relative to rat KHK. Direct evidencethat mutation of the KHK structural gene is the cause of essentialfructosuria was also obtained. In a well-characterized family,in which three of eight siblings have fructosurla, all affectedindividuals are compound heterozygotes for two mutations Gly40Argand Ala43Thr. Both mutations result from G