Analog enhancement of videomicroscope images

A simple, inexpensive technique for enhancing the contrast and resolution of videomicroscope images has been developed. The system has manual controls for gain and pedestal (black level) which permit expansion of low contrast images to the full white-to-black video range. Analog delay-line based circuits are used to sharpen the edges and enhance fine details in the image. These circuits also produce an effective increase in the information content of the image by selectively amplifying low amplitude, high frequency components of the video signal. When live, unstained cells were examined at high magnifications, cytoplasmic structures which were only faintly visible in the unenhanced image became clear. The images of fluorescent objects appear in pseudo-relief, which improves visibility even in the presence of background fluorescence. The system enhances images by performing signal processing functions that otherwise require expensive digital image processing equipment.

Video analysis of chemotactic locomotion of stored human polymorphonuclear leukocytes

Previous studies of the storage of polymorphonuclear leukocytes (PMNs) have used an empirical approach to define "optimal" conditions. To date, no storage conditions have been described which satisfactorily preserve the chemotactic function of PMNs beyond 24 h. In an effort to define the precise nature of the storage lesion, we studied the chemotactic locomotion of freshly isolated PMNs and PMNs which had been suspended in citrate-phosphate-dextrose-adenine (CPD-A1) plasma and stored in PVC bags, at 20-22 degrees C for 24 h. We used time-lapse video recording and computer image analysis to quantitate the motion of PMNs migrating under agarose. The positions of individual motile cells were traced at 1-min intervals for 5 min. The following parameters were used to quantitate migration: speed (distance/min), persistence of locomotion index (velocity/speed), orientation angle (the angle of the vector describing the next displacement of a cell relative to a direct line toward the chemoattractant), and chemotropic index (cosine of the orientation angle). After 24 h of storage, the following changes were observed: fewer cells migrated, the speed of migrating cells was reduced by 25%, the persistence of locomotion index decreased by 7%, which indicates that migrating cells made slightly more/wider turns, and the chemotropic index was decreased by 30%, which indicates that migrating cells were less accurate in their orientation toward the chemoattractant. Apparently, the storage of PMNs selectively impairs the ability of some cells to orient accurately in a chemotactic gradient and changes the distribution of these locomotor parameters within the population.

Biochemical characterization of a filtered synaptoneurosome preparation from guinea pig cerebral cortex: cyclic adenosine 3':5'-monophosphate-generating systems, receptors, and enzymes

A particulate preparation was obtained by low speed centrifugation of guinea pig cerebral cortical homogenates prepared with a Krebs-Henseleit buffer. Light microscopic examination, using a reflected light differential interference contrast system, reveals the presence of intact neurons, axonal fragments, glial cells, and erythrocytes along with an abundance of small spherical entities (diameter about 1.1 micron) and snowman-shaped entities (diameter of larger sphere about 1.1 micron, diameter of attached smaller sphere about 0.6 micron). Many unattached smaller spherical entities are also present (diameter about 0.6 micron). Pressure filtration through 5- or 10-micron Millipore filters, followed by low speed centrifugation and resuspension, removes most of the larger entities to afford a suspension composed mainly of the small spherical and snowman-shaped entities. Electron microscopic examination reveals the presence of many synaptosomes with attached resealed postsynaptic entities. It is proposed that these correspond to the snowman-shaped entities to be termed synaptoneurosomes. Accumulations of cyclic AMP elicited by 2-chloroadenosine and histamine, and by combinations of 2-chloroadenosine, histamine, norepinephrine, and forskolin, are lower in filtered than in unfiltered preparations, whereas accumulations elicited by forskolin are unchanged. Levels of adenylate cyclase are reduced by filtration, whereas levels of phosphodiesterase are unchanged. Filtration reduces levels of markers for whole cells and endothelial cells, whereas neuronal markers such as acetylcholinesterase activity and norepinephrine uptake are increased. Levels of S-100 protein, a marker for glial cells, are not significantly decreased. There is no apparent change in the density of many receptors or ion channels. Levels of A1-adenosine and H1-histamine receptors are increased, whereas levels of so-called peripheral benzodiazepine-binding sites are decreased.

Essential fatty acids in the plasma phospholipids of patients with atopic eczema

We have measured all the essential fatty acids (EFA) in plasma phospholipids in forty-one adults with atopic eczema and fifty normal controls. The major dietary n-6 EFA, linoleic acid, was significantly elevated, but all its metabolites, 18:3n-6, 20:3n-6, 20:4n-6, 22:4n-6, and 22:5n-6 were significantly reduced. The major dietary n-3 EFA, alpha-linolenic acid, was also elevated, though not significantly, while all its metabolites were also significantly reduced. These observations suggest that atopic eczema is associated not with any defect of EFA intake, but with abnormal metabolism, possibly involving the enzyme delta-6-desaturase. Treatment with oral evening primrose oil produced partial correction of the n-6 EFA abnormality, but had no effect on the n-3 EFAs.

Seborrhoea is not a feature of seborrhoeic dermatitis

The sebum excretion rate from forehead skin was measured in 44 patients with classic seborrhoeic dermatitis and 200 control subjects. The mean excretion rate was normal in the 29 men with seborrhoeic dermatitis and significantly reduced in the 15 women with the disease. This study showed that seborrhoeic dermatitis is not usually associated with seborrhoea, and therefore "dermatitis of the sebaceous areas" may be a more accurate term.

Reduced levels of prostaglandin precursors in the blood of atopic patients: defective delta-6-desaturase function as a biochemical basis for atopy

In the plasma phospholipids of a group of 50 young adults with atopic eczema, there was an elevation of cis-linoleic acid associated with a deficit of gamma-linolenic acid and of the prostaglandin precursors, dihomogammalinolenic acid and arachidonic acid. This suggests that atopics have a deficit in the function of the delta-6-desaturase enzyme which converts linoleic acid to gamma-linolenic acid. Carriers of cystic fibrosis tend to be phenotypically atopic, supporting previous suggestions that in homozygote cystic fibrosis patients the key defect may be in the delta-6-desaturase enzyme. Atopic patients may be exceptionally sensitive to side effects of non-steroidal anti-inflammatory agents. They fail to flush in response to application of niacin compounds to the skin, a reaction mediated by prostaglandins. A deficit of prostaglandin precursors would explain both of these observations. That the observed biochemical deficit plays a causative role in the manifestations of atopy was indicated by the fact that in a double-blind, placebo-controlled crossover trial, gamma-linolenic acid in the form of evening primrose oil (Efamol), partially corrected both the biochemical abnormalities and the clinical state.

Nail dystrophy due to diabetic neuropathy

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Absorption of ultraviolet radiation by skin surface lipid

The UVR absorption spectrum for skin surface lipid was measured by spectrometry. Significant absorption occurred throughout the UVR range, with a maximum at 215 nm. We estimate that the lipid normally present on forehead skin is likely to reduce transmission at 300 nm by about 10%.

Lack of effect of the antihistamine drug clemastine on the potentiation of itch by prostaglandin E1

The effect of clemastine fumarate, a histamine H1-antagonist, on the potentiation of itch by prostaglandin E1 (PGE1) was studied in normal humans. The antihistamine drug did not abolish the potentiation, which suggests that the effect of PGE1 on itch does not depend on the liberation of endogenous histamine.

Correlation of seasonal variation of 25-hydroxycalciferol with UV radiation dose

Plasma 25-hydroxycalciferol levels were measured in ten normal subjects at approximately 6-weekly intervals for 1 year. The mean annual level was 18.4 ng/ml with a seasonal variation from 14 to 26 ng/ml. These values correlated well with serial estimates of personal UV radiation dose previously measured by polysulphone film badges.

Sebaceous gland suppression in female acne patients by combined glucocorticoid-oestrogen therapy

Women with severe acne were treated with a combination of oestrogen and a low dose of glucocorticoid daily in order to suppress their androgen production. This combination therapy reduced their sebum production by 50%, with a concomitant improvement in their acne.

The effect of steroid and dithranol therapy on cyclic nucleotides in psoriatic epidermis

Absolute values of both cAMP and cGMP leves were measured in the involved and uninvolved skin of psoriatic patients, and also the effect of topical therapy on these levels in the involved skin was studied. The mean cGMP level in the untreated psoriatic plaque was increased by 300% compared to the non-involved skin (which did not differ from normal skin), but no significant difference in cAMP levels was found. Epidermal stripping of uninvolved skin, which stimulates cell proliferation, did not change the cGMP level. Treatment of the psoriasis with dithranol caused the cGMP levels to return to normal, but a potent topical glucocorticoid, in contrast, produced no such decrease. This may imply that the two drugs act at different levels in suppressing cell replication, and dithranol may be a useful tool for the further investigation of cyclic nucleotide metabolism.

A double-blind trial of metronidazole versus oxytetracycline therapy for rosacea

Forty patients with papulo-pustular rosacea were treated for 12 weeks on a random double-blind basis either with oxytetracycline 250 mg twice daily or with metronidazole 200 mg twice daily. Both drugs produced an improvement which was greater after 12 weeks than after 6 weeks, but there was no significant difference between them. Metronidazole appears to be a safe and effective drug for the treatment of rosacea.

Hypertrichosis due to minoxidil

A case of hypertrichosis due to the hypotensive drug minoxidil is described. A review of the literature suggests that this complication appears in nearly all patients treated with this drug. The mechanism is unknown, but the similarity to the cases of hypertrichosis due to diazoxide, another potent vasodilator, suggests that increased cutaneous blood flow may be a factor.

Erosive pustular dermatosis of the scalp

We report six patients with a previously undescribed but characteristic pustular dermatosis confined to the scalp. All the patients were elderly women who developed chronic, extensive, pustular, crusted and occasionally eroded lesions of the scalp which produced scarring alopecia. Investigations were essentially negative and skin biopsies showed only non-specific changes of atrophy and chronic inflammation, sometimes with increased plasma cells in the infiltrate. The condition did not respond to antibiotics, but was suppressed by potent topical steroids.

Male-pattern alopecia and masculinity

Cutaneous processes which are thought to be influenced by androgenic stimulation include the development of male-pattern alopecia, terminal hair distribution, sebum excretion rate, maximal sweat secretion rate and skin thickness. We measured these indices in forty-eight normal men, together with muscle, fat and bone thickness and plasma testosterone. There was a significant correlation between hair density on the forearm, leg and chest, but no other significant correlations were found. We conclude that bald men are no more 'masculine' than those with good scalp hair growth, if masculinity is defined in terms of end-organ response to androgenic stimulation.

Collagen sponge for leg ulcers

Collagen sponge, reconstituted from bovine tendon, provides a porous matrix for the permeation of fibroblasts and capillaries and on theoretical grounds it should be ideal for stimulating granulation tissue in deep leg ulcers. A preliminary study in six patients has suggested that a collagen sponge dressin enhanced granulation, but subsequent re-epithelialization over the reconstituted collagen tended to be slower than usual.

Azathioprine plus prednisone in treatment of pemphigoid

Twenty-five patients taking part in a controlled trial to compare azathioprine plus prednisone with prednisone alone in the treatment of pemphigoid were followed up for three years. Results showed that the addition of azathioprine 2.5 mg/kg body weight daily reduced the total maintenance dose of prednisone needed by about 45%, with no increase in serious side effects or mortality. The suggestion that azathioprine might increase the risk of disseminated malignancy in elderly patients was not supported. We conclude that in future trials the combination of azathioprine with prednisone should be used as the standard treatment for comparison.

A new syndrome with pigmentation, scleroderma, gynaecomastia, Raynaud's phenomenon and peripheral neuropathy

A middle-aged man developed impotence, gynaecomastia, peripheral neuropathy, pigmentation lymphadenopathy, scleroderma, malabsorption and Raynaud's phenomenon following prolonged exposure to trichlorethylene. Somes, but not all, of these features have previously been reported in vinyl chloride disease, and trichlorethylene is related chemically to vinyl chloride. Seven patients with a similar but not identical syndrome have been described in Japan and U.S.A., apparently unrelated to exposure to industrial toxins.