Responses to the sensory properties of fat of neurons in the primate orbitofrontal cortex

The primate orbitofrontal cortex is a site of convergence of information from primary taste, olfactory, and somatosensory cortical areas. We describe the responses of a population of single neurons in the orbitofrontal cortex that responds to fat in the mouth. The neurons respond, when fatty foods are being eaten, to pure fat such as glyceryl trioleate and also to substances with a similar texture but different chemical composition such as paraffin oil (hydrocarbon) and silicone oil [Si(CH3)2O)n]. This is evidence that the neurons respond to the oral texture of fat, sensed by the somatosensory system. Some of the population of neurons respond unimodally to the texture of fat. Other single neurons show convergence of taste inputs, and others of olfactory inputs, onto single neurons that respond to fat. For example, neurons were found that responded to the mouth feel of fat and the taste of monosodium glutamate (both found in milk), or to the mouth feel of fat and to odor. Feeding to satiety reduces the responses of these neurons to the fatty food eaten, but the neurons still respond to some other foods that have not been fed to satiety. Thus sensory-specific satiety for fat is represented in the responses of single neurons in the primate orbitofrontal cortex. Fat is an important constituent of food that affects its palatability and nutritional effects. The findings described provide evidence that the reward value (or pleasantness) of the mouth feel of fat is represented in the primate orbitofrontal cortex and that the representation is relevant to appetite.     

hMLH1 promoter methylation and lack of hMLH1 expression in sporadic gastric carcinomas with high-frequency microsatellite instability

The frog intermediate lobe consists of a single endocrine cell type, the melanotrope cells, which are under the tonic inhibitory control of dopamine. Separation of dispersed pars intermedia cells in a Percoll density gradient has revealed the existence of two melanotrope cell subpopulations, referred to as high-density (HD) and low-density (LD) cells. The aim of the present study was to investigate the effects of dopamine on each of these melanotrope cell subsets. Increasing doses of dopamine, ranging from 10(-9)-10(-6) M, inhibited the release of alpha-melanocyte-stimulating hormone (alpha-MSH) in LD (but not in HD) melanotrope cells. In addition, dopamine provoked a significant reduction of the rate of acetylation of alpha-MSH in LD cells but not in HD cells. Similarly, dopamine significantly decreased the accumulation of POMC messenger RNA in LD cells, whereas it did not affect POMC gene expression in the HD melanotrope subset. On the other hand, microfluorimetric studies revealed that dopamine induced a significant reduction of KCl-stimulated cytosolic free calcium concentration in both LD and HD cells. The present study provides additional evidence for functional heterogeneity of melanotrope cells in the frog pars intermedia. Because dopamine plays a pivotal role in the regulation of alpha-MSH secretion, these data suggest the involvement of cell heterogeneity in the physiological process of background color adaptation in amphibians.     

Candida albicans sensitization in patients with atopic bronchial asthma and atopic dermatitis

Candida albicans, a component of normal human microflora, can induce synthesis of specific IgE-antibodies in patients with atopic bronchial asthma and atopic dermatitis. The study included 25 patients with atopic dermatitis sensitized to C.albicans and 23 patients with atopic dermatitis non-sensitized to C.albicans. The sensitization was determined by the skin test and enzyme immunoassay. The patients had the history of atopic dermatitis exacerbation after taking food containing baking yeasts. Atopic dermatitis with sensitization to C.albicans is characterized by severe course correlating with the following indices: high total IgE (r = 0.6), level of IgE antibodies to C.albicans (r = 0.6), level of serum IgG (r = 0.46) and IgA (r = 0.33). Contrary to adults, children with sensitization to C.albicans had decreased relative number of CD4+, CD8+ and CD72+ of lymphocyte subpopulations. Thus, sensitization to C.albicans manifests in severe atopic dermatitis which in children is often associated with immune deficiency.     

A patient with Wegener''s granulomatosis presenting with a subarachnoid hemorrhage: case report and review of CNS disease associated with Wegener''s granulomatosis

1. Travellers to high altitude often complain of paroxysmal cough, which has not been previously investigated. We recorded overnight cough frequency and cough-receptor sensitivity to inhaled citric acid in a group of climbers travelling to 5300 m or higher. 2. Cough frequency, monitored in ten subjects, increased from a median of 0 coughs at sea level (range 0-1) to 5 coughs at 5000 m (range 0-13) and to over 60 coughs in subjects ascending to 7000 m. Citric acid cough threshold, measured in 42 subjects, was unchanged on arrival at 5300 m compared with sea level (geometric mean difference 1.26, 95% confidence intervals 0.84-1.89, P = 0.25), but was significantly reduced after 6 days, or more, at altitude compared with sea level (geometric mean difference 2.2, 95% confidence intervals 1.54-3.15, P = 0.0002). Cough threshold was not related to symptoms of acute mountain sickness, oxygen saturation, carbon dioxide tension or lung function. 3. These results indicate an increase in cough and cough-receptor sensitivity after some days at altitude. This may be due to respiratory tract damage from breathing cold dry air at increased ventilatory rates. Other explanations, such as sub-clinical pulmonary oedema or an effect on the cough centre of acclimatization to altitude, cannot be excluded.     

Squamous cell carcinoma in individuals under 40 years of age

We reviewed all the cases of Squamous Cell Carcinoma in people under 40 years of age, diagnosed histologically at the Dermatopathology Laboratory of the Santa Maria Hospital, from January 1985 to December 1993. The 19 cases detected were analysed for age, sex, occupation, anatomical site of the tumor, evolution, smoke and alcoholic habits, skin phototypes, immunosuppression, previous viral infections, previous radiotherapy or PUVA therapy and associated diseases. A prevalence of an occupation involving more exposure to the sun was found. Males were more affected than females (2.2/1). In 37% of the patients we detected heavy alcoholic habits. The most frequent anatomical site was the lower lip (42%). Patients with skin phototype I were more affected (53%).     

Quantitative responses of serum folate to increasing intakes of folic acid in healthy women

OBJECTIVES: Health authorities are advising people to increase folate intake and more foods are being fortified with folic acid. Estimation of dietary folate is difficult because nutrient data bases lack this nutrient in many countries and bioavailability is variable. To see if serum folate can be used to reflect effective folate intake, we have measured serum folate after healthy women had taken different doses of pure folic acid supplements in the nutritional range. METHODS: A total of 20 volunteer subjects took part in one or more of three experiments, six of them took part in all three. In each experiment subjects took two different doses of folic acid, each for three weeks. Experiment (1) 100 micrograms then 1000 micrograms/d; experiment (2) 500 micrograms then 1500 micrograms/d; experiment (3) 1000 then 2000 micrograms/d. Serum folate was measured after overnight fast with a homogenous enzyme binding assay kit. In experiment (3) red cell folates were also measured. RESULTS: It took three weeks' of the same supplement for serum folate to reach its full higher value. Mean serum folates of small groups of subjects were significantly higher with each higher dose of supplement. The biggest increase was for the first 100 micrograms that is in the range of intake from unfortified foods. The curve of serum folate against folic acid supplement intake shows that serum folate of groups of people, properly standardized, can provide a practical method for assessing adequacy or change of people's folate intake. Red cell folates were less responsive.