Ultrastructure and light microscopical study of a Leydig cell tumor of the testis associated with bilateral gynaecomastia

Light and electronmicroscopic study of a Leydig cell testicular tumor in an 18-year-old male is presented. Bilateral gynaecomastia and normal hormonal blood levels were found. Emphasis on the diagnostic value of electronmicroscopy is remarked upon, based on the following ultrastructural characteristics of the cells; 1) Ovoid shaped nuclei with ondulating contours and dispersed and homogeneous chromatin, 2) Rich agranular endoplasmic reticulum with frequent special modifications, such as membranous whorls with a central cytoplasmic mass or lipid droplets, 3) Numerous mitochondria with occasional tubular cristae, 4) Numerous lipid vacuoles. Other structures also identified in this tumor are Reinke crystalloids, cytoplasmic microbodies, myelin figures, gap-type junctional complexes and paracrystalline inclusions of Payer type E, which are less common.     

Allozyme divergence among four species ofPodaechmea s. l. and the status ofUrsulaea (Bromeliaceae, Bromelioideae)

The genetic relationships ofAechmea mexicana, A. lueddemanniana, A. macvaughii andA. tuitensis were investigated using starch gel electrophoresis. Eight enzyme systems encoded by ten putative gene loci were resolved in seventeen populations.Nei's (1978) genetic distances were obtained from allelic frequencies and used with UPGMA algorithm. Results indicate that some populations belonging to different species display genetic similarities closer to each other than to some conspecific populations. Our results do not support the proposed genusUrsulaea (Read & Baensch 1994), sinceA. tuitensis was closer toA. lueddemanniana andA. mexicana than toA. macvaughii.     

Effects of context on judgements of odor intensities in humans

This study evaluated whether the intensity of previously smelled odors could unintentionally influence the subsequent judgement of odor intensity. The predicted context effect was based on the adaptation- level theory. Before and 25 min after either WEAK or STRONG biasing odor concentrations, 51 subjects were required to rate the intensity of 10 different odor concentrations of California Orange Oil. After the WEAK bias, subjects judged the odor intensity as being stronger than they did after the STRONG bias. Thus the intensity of odors smelled 25 min earlier can unintentionally influence subsequent odor intensity judgement. The findings are discussed in the light of two alternative explanations, namely, a central implicit memory process and a stimulus- level-based change at the peripheral level.      

Review of the clinical efficacy of flutrimazole gel in the treatment of dandruff and/or seborrheic dermatitis.

The purpose of this article is to review the phase II and phase III clinical trials with the new pharmaceutical gel form of flutrimazole. The aim of the phase II study was to determine the efficacy and tolerance of flutrimazole 1%, 2% and 4% gel when compared to placebo in the treatment of 80 patients with dandruff or seborrheic dermatitis at a dose of three applications per week during one month. Flutrimazole 1% gel had a similar efficacy compared to the other studied concentrations and a superior efficacy when compared to placebo (p < 0.05). All treatments studied had an excellent tolerance. In the phase III study, the efficacy and tolerance of flutrimazole 1% gel was compared to ketoconazole 2% gel in 192 patients with dandruff or seborrheic dermatitis. Flutrimazole gel had a similar efficacy to ketoconazole gel at a dose of three applications per week for 28 days. Both products were well tolerated and no adverse effects were recorded.     

Nucleotide sequence of the D-loop region of the sperm whale (Physeter macrocephalus) mitochondrial genome

We have amplified, by the polymerase chain reaction, and have sequenced the D-loop region of the mitochondrial DNA from the sperm whale (Physeter macrocephalus). The sperm whale D-loop was aligned with D- loop sequences from four other cetaceans (Commerson's dolphin, orca, fin whale, and minke whale) and an out-group (cow). This alignment showed the sperm whale sequence to be larger than that of other cetaceans. In addition, some sequence blocks were highly conserved among all six species, suggesting roles in the functioning of mitochondrial DNA. Other blocks that were previously reported to be well conserved among cetaceans showed little sequence conservation with the sperm whale D-loop, which argues against the functional importance of these sequence blocks in cetaceans.      

Inertial vestibular coding of motion: concepts and evidence

Central processing of inertial sensory information about head attitude and motion in space is crucial for motor control. Vestibular signals are coded relative to a non-inertial system, the head, that is virtually continuously in motion. Evidence for transformation of vestibular signals from head-fixed sensory coordinates to gravity-centered coordinates have been provided by studies of the vestibulo-ocular reflex. The underlying central processing depends on otolith afferent information that needs to be resolved in terms of head translation related inertial forces and head attitude dependent pull of gravity. Theoretical solutions have been suggested, but experimental evidence is still scarce. It appears, along these lines, that gaze control systems are intimately linked to motor control of head attitude and posture.