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A family with X-linked cytochrome-negative chronic granulomatous disease (CGD) involving three generations is reported. The diagnosis of CGD in both the latest male patient and the index male was confirmed by marked impairment in polymorphonuclear leucocyte oxidative burst activity in association with absence of both subunits of cytochrome b. The two female carriers have suffered from chronic inflammatory skin disorders characterized by slowly fluctuating erythematous plaques. The reported cases are discussed in the context of a literature review of the dermatosis of CGD.

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Hydrogen cyanide polymers form spontaneously from HCN and traces of base catalysts. It is probable that these polymers played an important role in the early stages of chemical evolution. Nevertheless, their full structural characterization has still not been accomplished. A number of mass spectrometric methods have now been applied to this structural problem including FAB-MS, thermal desorption EI-MS, ESI-MS, APCI-MS and off-line TMAH thermochemolysis/GC-MS. This latter method causes bond cleaveage and in situ methylation producing a suite of products which provides valuable insight into the substructural features of HCN polymers and also promises to serve as a sensitive diagnostic tool for detecting the presence of HCN polymers in samples from diverse sources.

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Hydrogen cyanide polymers--heterogeneous solids ranging in color from yellow to orange to brown to black--may be among the organic macromolecules most readily formed within the Solar System. The non-volatile black crust of comet Halley, for example, as well as the extensive orange-brown streaks in the atmosphere of Jupiter, might consist largely of such polymers synthesized from HCN formed by photolysis of methane and ammonia. Laboratory studies of these ubiquitous compounds point to the presence of polyamidine structures synthesized directly from hydrogen cyanide. These would be converted by water to polypeptides which can be further hydrolyzed to alpha-amino acids. Other polymers and multimers with ladder structures derived from HCN would also be present and might well be the source of the many nitrogen heterocycles, adenine included, detected by thermochemolytic analysis. The dark brown color arising from the impacts of comet P/Shoemaker-Levy 9 on Jupiter could therefore be mainly caused by the presence of HCN polymers, whether originally present, deposited by the impactor or synthesized from freshly formed HCN. Spectroscopic detection of these predicted macromolecules and their hydrolytic and pyrolytic by-products would strengthen significantly the hypothesis that cyanide polymerization is a preferred pathway for prebiotic and extraterrestrial chemistry.

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Hydrogen cyanide polymerizes readily to a black solid from which a yellow-brown powder can be extracted by water and further hydrolyzed to alpha-amino acids. These macromolecules could be major components of the dark matter observed on many bodies in the outer solar system, including comets and asteroids. Primitive Earth might therefore have been covered with HCN polymers through bolide bombardment or be terrestrial synthesis. Several instrumental methods were used for the separation and identification of these intriguing polymeric materials, including photoacoustic Fourier transform infrared spectroscopy, supercritical fluid extraction chromatography and pyrolysis mass spectrometry. Our integrated analytical approach revealed fragmentation patterns and chemical functionalities consistent with the presence of polymeric peptide precursors both in HCN polymers and in the Murchison meteorite.

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Bazex disease is one of the rarer cutaneous paraneoplastic syndromes. It is characterized by psoriasiform changes on the digits, and in some patients spread to the ears, nose and in later stages to the limbs and trunk. The associated malignancy is typically a squamous cell carcinoma of the upper aerodigestive tract. We review the literature regarding acrokeratosis paraneoplastica of Bazex and report three cases which illustrate both the typical and some of the less common changes that are seen in the condition.

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The original presence on cometary nuclei of frozen volatiles such as methane, ammonia and water makes them ideal sites for the formation and condensed-phase polymerization of hydrogen cyanide. We propose that the non-volatile black crust of comet Halley consists largely of such polymers. Dust emanating from Halley's nucleus, contributing to the coma and tail, would also arise partly from these solids. Indeed, secondary species such as CN have been widely detected, as well as HCN itself and particles consisting only of H, C and N. Our continuing investigations suggest that the yellow-orange-brown-black polymers are of two types: ladder structures with conjugated -C=N- bonds, and polyamidines readily converted by water to polypeptides. These easily formed macromolecules could be major components of the dark matter observed on the giant planets Jupiter and Saturn, as well as on outer solar system bodies such as asteroids, moons and other comets. Implications for prebiotic chemistry are profound. Primitive Earth may have been covered by HCN polymers either through cometary bombardment or by terrestrial happenings of the kind that brought about the black crust of Halley. The resulting proteinaceous matrix could have promoted the molecular interactions leading to the emergence of life.

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Current research in cosmochemistry shows that crude organic solids of high molecular weight are readily formed in planetary, interplanetary and interstellar environments. Underlying much of this ubiquitous chemistry is a low energy route leading directly to the synthesis of hydrogen cyanide and its polymers. Evidence from laboratory and extraterrestrial investigations suggests that these polymers plus water yield heteropolypeptides, a truly universal process that accounts not only for the past synthesis of protein ancestors on Earth but also for reactions proceeding elsewhere today within our solar system, on planetary bodies and satellites around other stars and in the dusty molecular clouds of spiral galaxies. The existence of this preferred pathway - hydrogen cyanide polymerization - surely increases greatly the probability that carbon-based life is widespread in the universe.

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Using telescopic observations by ourselves and other observers, we have identified cyano-group containing molecules in the very dark solids on the surfaces of a few D-class asteroids, the dust of some comets, and low-albedo hemisphere of Iapetus, and the rings of Uranus, through spectroscopic detection of the 2.2-micrometers overtone of the C triple bond N stretching fundamental mode. The occurrence of this band on all four classes of small Solar System bodies may be diagnostic of the duration of exposure and degree of modification of surface materials, and may also establish a link between outer Solar System and interstellar materials.

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Since hydrogen cyanide is a component of Titan's hazy atmosphere, HCN polymers might also be present by way of a low energy pathway leading initially to the synthesis of polyaminomalonitrile. Subsequent reactions of HCN with the activated nitrile groups of this HCN homopolymer would then yield heteropolyamidines, readily converted to heteropolypeptides following contact with frozen water on the surface of Titan. Similar HCN polymers in the reducing atmospheres of Jupiter and Saturn could be major contributors to the yellow-brown-orange appearance of these giant planets. Any detection of such HCN chemistry by the Voyager missions or the pending Galileo probe would constitute evidence for the hypothesis that heteropolypeptides on the primitive Earth were synthesized directly from hydrogen cyanide and water without the intervening formation of alpha-amino acids.

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In ten patients suffering from symptomatic dermographism the combined administration of chlorpheniramine + cimetidine produced a greater reduction in the weal and flare response provoked by a standardized scratch than the administration of chlorpheniramine alone. There was a statistically significant improvement in the overall assessment of the patient's skin condition with the combined administration of chlorpheniramine + cimetidine. Chlorpheniramine given alone produced no significant benefit whilst cimetidine alone produced a marked exacerbation in itching in nearly half the patients who initially entered the study and was sufficient to require withdrawal.

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A cases of systemic lupus erythematosus is reported, presenting with urticaria-like lesions and complement deficiencies, which was completely controlled by dapsone.

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'Fiddler's neck' is a condition affecting violin and viola players. Although well known to musicians it is not well recognized by dermatologists. Clinically the lesions usually consist of a localized area of lichenification of the left side of the neck--just below the angle of the jaw. Pigmentation, erythema and inflammatory papules or pustules are frequently present, while severe inflammatory induration, cyst formation and scarring occur in more severely affected subjects. The aetiology of the skin changes is probably due to a combination of factors; friction giving rise to lichenification, while local pressure, shearing stress and occlusion may play a part in producing the acne-like changes and cyst formation. In addition, poor hygiene may predispose to local sepsis.

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