Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043346 (xeroderma pigmentosum)
 2,924 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The reactions to monochromatic radiation of the skin of ten patients with xeroderma pigmentosum were investigated, and eight were abnormal. The abnormalities consisted of papular and vesicular reactions and delay in the development of the minimal erythema dose reaction with wavelengths principally in the 290-320 nm range. Three patients were too young for full action spectra to be obtained but of those patients in whom all wavelengths were tested only one showed a reaction to radiation above 320 nm and this was at 340 nm only. In only one patient was the minimal erythema dose at 300 nm at 24 h lower than normal. In six patients the repair synthesis of deoxyribonucleic acid after ultraviolet radiation was estimated. Reduced levels were seen in five but repair was normal in one patient. The patient with normal repair also had normal reactions to monochromatic radiation. The abnormal reaction of the skin to artificial radiation and the abnormal deoxyribonucleic acid repair synthesis may enable the diagnosis of xeroderma pigmentosum to be made at a very early age. In one of the patients the diagnosis was made at the age of 6 months in a child with photosensitivity but with no other clinical signs of the disease. It is suggested that, by making the diagnosis as early as possible and by protecting the skin from natural sunlight, cutaneous malignancies may be prevented.
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PMID:The erythemal action spectrum and deoxyribonucleic acid repair synthesis in xeroderma pigmentosum. 115 44

Skin exposure to UVB radiation deprives the antigen-presenting function and OKT6 monoclonal antibody-binding characteristics of Langerhans cells. Decrease of Langerhans cell population could be relevant to immune surveillance disturbance in the UV-exposed skin. Patients with xeroderma pigmentosum exhibit a thousandfold higher risk for sunlight-induced skin cancers than patients with normal skin, and also have various defects in cellular immunity. Therefore, studies of numerical and structural changes in epidermal Langerhans cells of patients with xeroderma pigmentosum after UVB irradiation compared with normal subjects may contribute to understanding the role of antigen-presenting cells in photocarcinogenesis. The effect of UVB radiation on OKT6+ Langerhans cells was studied in epidermal sheets obtained from irradiated normal subjects (36 and 49 years old) and subjects with xeroderma pigmentosum complementation group A (21 years old), complementation group D (32 years old), and variant (35 and 60 years old). Langerhans cell densities in chronically sunlight-exposed skin were remarkably reduced in patients with xeroderma pigmentosum group A but only slightly in those with xeroderma pigmentosum variant and in normal subjects compared with covered skin. Structural changes were substantial in Langerhans cells of chronically exposed patients with xeroderma pigmentosum group A but fewer in subjects with other xeroderma pigmentosum groups and in normal subjects. A single irradiation of three times the minimal erythema dose induced a large reduction of Langerhans cells from 3 to 7 days in all subjects. However, subsequent reappearance and return to preirradiated levels was delayed more in patients with xeroderma pigmentosum group A than in those with xeroderma pigmentosum variant and normal subjects. These results indicate (1) an essential role for excisional repair in the UVB-induced depletion, recovery, and maintenance of the epidermal Langerhans cell population, and (2) a possible, but not confirmed, relationship between depletion of Langerhans cells and earlier photocarcinogenesis in xeroderma pigmentosum.
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PMID:Role of excision repair in UVB-induced depletion and recovery of human epidermal Langerhans cells. 173 89

Skin phototesting and cellular sensitivity studies were performed in a patient with xeroderma pigmentosum (XP) complementation group E (XP80TO) at the ages of 50 and 55 years. She showed a reduced minimal erythema dose at both ages, but the dose at age 55 was much lower than that at age 50 when tested with monochromatic ultraviolet (UV) light (280, 290 and 300 nm). The cellular sensitivity to UVC (254 nm), UVB and UVA and UVC-induced unscheduled DNA synthesis were examined using fibroblasts obtained by skin biopsy at the ages of 50 and 55 (XP80TO-1 and XP80TO-2, respectively). DNA synthesis was similar in both cell lines. XP80TO-2 cells were more sensitive to UVB cytotoxicity than XP80TO-1 cells in both the dividing and quiescent phases, but both cell lines exhibited a similar sensitivity to UVC and UVA. These results suggest that the in vitro cellular sensitivity to UVB may correlate with the clinically observed erythema reaction. Further, the results suggest that some XP complementation group E cases at least may show an increase in photosensitivity in vivo and in vitro with aging.
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PMID:Age-related changes in photosensitivity and cellular sensitivity to ultraviolet B in a xeroderma pigmentosum group E patient. 175 17

A 43-year-old man with xeroderma pigmentosum, XP97TO, was allocated to complementation group D. He had had moderate photosensitivity at age 1 year and freckles by age 6 but no neurologic abnormalities. Nevertheless, his fibroblasts in culture had the XP-D phenotype. They showed a sevenfold hypersensitivity to killing by 254 nm ultraviolet radiation and a diminished level (29%) of unscheduled DNA synthesis. Phototesting revealed delayed maximum erythema at 72 hours after UVB exposure and a lowered minimal erythema dose. Lentigo maligna developed on the patient's face, and a rapidly growing malignant schwannoma was found on the left trigeminal nerve. This may be the first case of a peripheral nervous tissue neoplasm in xeroderma pigmentosum.
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PMID:Malignant schwannoma associated with xeroderma pigmentosum in a patient belonging to complementation group D. 189 71

In three children with Cockayne's syndrome (CS), skin exposed to ultraviolet radiation responded transiently either with erythematous papules or an exaggerated sunburn-like response, without chronic actinic damage. Irradiation monochromator tests demonstrated an abnormal delay or reduction in the threshold to ultraviolet (UVB) irradiation-induced erythema similar to that of xeroderma pigmentosum (XP). As with XP there was an elevated frequency of mutants resistant to 6-thioguanine in circulating T lymphocytes. The mutant frequency in a single obligate heterozygote was normal. In contrast to XP, in the two CS individuals studied, adaptive cell-mediated immunity and natural killer cell function were normal. Because the risk of skin cancer is very high in XP but not in CS, the normal immune function in CS provides evidence that immune surveillance may be important in UV tumorigenesis.
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PMID:Abnormal erythemal response and elevated T lymphocyte HRPT mutant frequency in Cockayne's syndrome. 203 22

A case of xeroderma pigmentosum group D in 36-year-old woman (XP85TO) is reported. The patient had severe photosensitivity from age 4, and developed multiple basal cell epitheliomas and solar keratoses but exhibited no apparent neurological defects. A skin phototest by monochromatic ultraviolet light revealed a delayed peak of erythema 48 h after irradiation and lowered minimal erythemal doses. Unscheduled DNA synthesis induced in XP85TO cells was 36.0% in dermal fibroblasts and 32.6% in epidermal keratinocytes compared with normal cells. The XP85TO cells were sensitive to ultraviolet killing (n = 1.0, D0 = 0.80 J/m2). In complementation analysis, XP85TO cells did not complement with xeroderma pigmentosum group D cells. These results indicate that patient XP85TO had xeroderma pigmentosum group D. The Japanese group D patients including XP85TO case showed delayed onset of skin malignant tumors and neurological abnormalities, compared with the group D patients in Europe and the United States. These findings suggest a possible ethnic variation of the clinical phenotype, despite the similar repair defect and ultraviolet hyperssensitivity.
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PMID:A case of xeroderma pigmentosum group D determined by photobiological study. 205 Sep 4

Langerhans cells (LC) in epidermis are antigen presenting cells. LC may play a role in immune surveillance system and are considered to suppress development of ultraviolet (UV) induced skin cancers. We studied effect of UVB irradiation to LC of xeroderma pigmentosum (XP) and normal subjects by using OKT6 monoclonal antibody. When 3 minimal erythema dose (MED) of UVB were irradiated, density of OKT6 positive LC of XP began to decrease 6 hours after irradiation, and showed the least numbers on day 2 and returned completely to the pre-irradiation level on day 14. Further, after 3 MED irradiation, LCs of both normal subjects became the least on day 3 and returned to the pre-irradiation level on day 14. In XP variant and normal subjects, the number of LC in chronic sun-exposed skin decreased significantly in a similar way comparing to that of non-exposed skin. These results suggest that epidermal LC may not play an essential role in prevention of UV-induced tumor development.
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PMID:[Do OKT6 positive Langerhans cells play a role in the suppression of ultraviolet-induced carcinogenesis?]. 223 92

A 35-year-old Japanese female patient with xeroderma pigmentosum (XP), registered as XP114TO, was assigned to complementation group D by the cell fusion complementation test. The patient had manifested moderate solar sensitivity and freckles by the age of 6 years. The skin phototest using 290- and 300-nm monochromatic ultraviolet (UV) light revealed slightly lowered minimal erythema doses at 24 h after irradiation. The XP114TO skin fibroblasts exhibited about the 6-fold higher sensitivity to the lethal effect of 254-nm UV as did normal cells. Unscheduled DNA synthesis (UDS) induced in XP114TO cells by 254-nm UV (10 J/m2) was 33% of normal, falling into the group D range of 25-50% UDS. The patient developed lentigo maligna on the right side of the nose. Unlike the typical XP group D cases in the West, she showed no neurological abnormalities.
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PMID:Xeroderma pigmentosum group D patient bearing lentigo maligna without neurological symptoms. 224 81

For precise measurements of minimal erythema dose (MED) in photosensitive dermatoses, a calibrating control unit was developed for a grating monochromator. Seasonal and sexual differences of wavelength-specific MED and the effects of different half-value wave-width for each wavelength were determined in 64 healthy adults. Wavelength-specific MED was studied using the apparatus in 19 patients with photosensitive dermatoses, including 2 patients with xeroderma pigmentosum, 2 patients with polymorphous light eruption, one patients with actin reticuloid, 2 patients with drug-induced photosensitive dermatitis and 2 patients with hydroa vacciniforme.
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PMID:[Development of a calibrating control unit for a grating monochromator and its clinical application]. 237 Jul 5

Multi-modality evoked potentials in two cases, who were siblings, of De Sanctis-Cacchione syndrome were reported. The case 1, who was elder sister of the case 2, was a 25-year-old female. And the case 2 was a 23-year-old female. They have the history of consanguinity. They were first noted to have skin erythema on exposure to sunlight, and a diagnosis of xeroderma pigmentosum was made. At the childhood neurological manifestation, such as mental retardation, deafness and muscular weakness developed gradually. The case 2, who was a elder sister, was operated on for squamous cell carcinoma of the eyelid at the age of 20 and 21 years old. Motor conduction velocity obtained from lower limbs were severely reduced and that from upper limbs were moderately delayed. Sensory conduction velocity of median nerve were severely diminished. Auditory brainstem responses (ABR) of the case 1 showed the prolongation in interpeak latency of I-V. ABR of the case 2 could not be obtained. N19 and N13 of short-latency somatosensory evoked potentials (SSEP) to median nerve stimulation with case 2 could not be obtained too. N13-N19 latency of case 1 was remarkably prolonged compared to the normal subjects. Central motor conduction time (CMCT) was studied in case 2 by using the magnetic stimulator. CMCT of case 2 was within the upper limit of normal control. Interpeak latency of I-V in ABR represents the brainstem dysfunction in auditory pathway, and interpeak latency of N13-N19 in SSEP was recognized as central conduction time from medial lemniscus to primary sensory area of cortex. So the prolongation of these interpeak latency in this cases may mean the dysfunction in the central nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Electrophysiological studies in siblings of De Sanctis-Cacchione syndrome]. 261 4


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