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)

Sib patients with xeroderma pigmentosum (XP), XP90TO (42 years old, male) and XP92TO (40 years old, female, were assigned to group F by the complementation analysis in hybridized heterodikaryons. The XP90TO and XP92TO fibroblasts exhibited the typical XPF characteristics of a threefold higher sensitivity to the lethal effect of 254 nm UV and a reduced level of 12% unscheduled DNA synthesis (UDS) compared with normal cells. Clinically, both patients manifested moderate to severe acute sun sensitivity by age 8, pigmented freckles by age 10 and skin malignancies at higher ages (6 basaliomas at 42 years in XP90TO; 1 basalioma at 41 years in XP92TO). Despite the still currently sun-sensitive state, the patients showed normal minimal erythema dose (MED) at monochromatic wavelengths of 290, 300 and 305 nm but abnormally delayed peaking of erythema reaction at 48 h after exposure. After irradiation with more than 3 MED, XP92TO showed a long persistence of induced erythema for at least 7 days. A review of the 16 reported XPF patients indicated mild skin manifestations, no neurological abnormalities, and more delayed skin carcinogenesis at a lower frequency than that in XPA patients. In addition, we have collected clinical information from Japanese XP patients in rare complementation groups D and E and reviewed their clinical and photobiological characteristics.
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PMID:Late onset of skin cancers in 2 xeroderma pigmentosum group F siblings and a review of 30 Japanese xeroderma pigmentosum patients in groups D, E and F. 266 29

Twenty patients with xeroderma pigmentosum group A (XP-A) and 30 healthy controls were studied to determine the energy requirements for UV-erythema with monochromatic light between 255 and 340 nm. As test sites, unexposed skin on the upper back was selected for irradiation using a prism monochromator and a 1 kW xenon arc source. The minimal erythema doses (MEDs) were determined at each erythemal response peak, at 24 hours post irradiation in normal controls and at 72 hours in XP-A patients, respectively. Compared with normal subjects, XP-A patients had extremely low MEDs at all wavelengths tested. The erythema action spectrum showed 2 peaks at 265 and 290 nm in XP-A patients and the greatest effectiveness at 290 nm. These results indicate that XP-A patients should be protected strongly against not only UVB but also UVA, because the photo-hypersensitivity in XP-A patients has been extended from the UVB to UVA region.
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PMID:[Erythema action spectrum in xeroderma pigmentosum group A patients]. 274 65

Three cases belonging to xeroderma pigmentosum (XP) complementation group E were analyzed clinically and photobiologically. The three Japanese patients were a 50-yr-old female (XP80TO), a 42-yr-old female (XP81TO), and a 41-yr-old female (XP82TO). They were assigned to complementation group E by the cell hybridization study. All showed lowered minimal erythema doses between those of normal Japanese and XP group A subjects at wavelengths of 280, 290, and 300 nm of monochromatic ultraviolet (UV) light. Patients XP80TO and XP81TO, but not patient XP82TO, showed a delayed peak reaction at 48 h to UV erythema. All fibroblast strains from these patients had a reduced level of 40%-44% unscheduled DNA synthesis (UDS) after irradiation with 10 J/m2 of 254 nm UV. Primary cultured epidermal cells from these patients exhibited a relatively low level of UDS (ie, 38%-51% of normal epidermal cells). All of the group E fibroblast strains were twice as sensitive to 254 nm UV killing [n (extrapolation number) = 1.3-1.8, Do (mean lethal dose) = 2.2-2.8 J/m2)] as normal fibroblasts (n = 1.5, Do = 5.0 J/m2). All of the above group E patients had mild XP symptoms, but not neurological abnormalities, at the fifth decade of age. Patients XP80TO and XP81TO had developed skin malignancies (patients XP80TO developed three basaliomas; patient XP81TO developed two basaliomas) at the ages of 46 and 41 yr, respectively.
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PMID:Assignment of three patients with xeroderma pigmentosum to complementation group E and their characteristics. 333 59

A 31-year-old female patient with xeroderma pigmentosum (XP) XP43KO was assigned to complementation group D by the cell-fusion complementation methods. Cultured XP43KO cells from our patient had the defective DNA repair phenotype showing a residual level of ultraviolet (UV)-induced unscheduled DNA synthesis (45% of normal) and an eightfold higher sensitivity to 254-nm UV killing, compared with normal cells. The phototest on the patient revealed the delayed maximum reaction to UV-B-induced erythema and lower minimal erythema doses at 290- and 300-nm monochromatic wavelengths. However, the XP43KO patient showed no apparent neurologic abnormalities and rather mild or moderate skin lesions at the age of 31 years, although DNA repair deficiency in XP43KO cells from our patient fell into the range of group D cells.
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PMID:No apparent neurologic defect in a patient with xeroderma pigmentosum complementation group D. 334 5

A 65-year-old patient with xeroderma pigmentosum (XP), XP77TO, was assigned to complementation Group D by the cell-fusion study and comprised the fifth Group D case in Japan. The patient had mild solar sensitivity by age 7, dyspigmentation by 10 years, and he still currently has moderate symptoms. The skin phototest by 290, 300 and 305 nm monochromatic ultraviolet (UV) light revealed a delayed peak of erythema 48 h post-irradiation and lowered minimal erythemal doses. The XP77TO skin fibroblasts, as well as a reference Group D strain, exhibited the same 7-fold higher sensitivity to the lethal effect of 254 nm UV as did normal cells. Unscheduled DNA synthesis (UDS) induced in XP77TO cells by 254 nm UV (10 J/m2) was 42% of normal, falling into the Group D range of 25-50% UDS. In spite of such a similar cellular phenotype, XP77TO developed squamous cell carcinomas at 44 and 65 years of age and audiometric sensorineural deafness in a delayed fashion at advanced age.
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PMID:Delayed sensorineural deafness and skin carcinogenesis in a Japanese xeroderma pigmentosum group D patient. 339 39

Minimal erythema dose of ultraviolet light correlated significantly with the UV-sensitivity of fibroblast cells from 5 patients with xeroderma pigmentosum, 13 patients with keratinocytic neoplasms of the skin, and 21 control subjects, but not with that of cells from 6 patients with photosensitive dermatitis. In unscheduled DNA synthesis after UV irradiation, the number of grains per nucleus was much less in keratinocytes than in fibroblasts, but the relative dose-response relationship was similar. This indicates that keratinocytes can also be used in vitro UV-sensitivity studies.
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PMID:Comparisons of in vivo and in vitro photosensitivities and DNA repair in fibroblast and keratinocyte cells. 356 36

A 5-year-old female Japanese patient with mild symptoms of xeroderma pigmentosum (XP), XP7OTO, was assigned to complementation group E following cell hybridization. XP7OTO showed lowered minimal erythema doses compared with those of normal Japanese and XP group A subjects at 290 and 300 nm of monochromatic ultraviolet (UV) light. The delayed peak reaction of UV erythema was characteristically observed in this particular group E patient. 254 nm UV-induced unscheduled DNA synthesis of XP7OTO skin fibroblasts was reduced to a level of 55% of normal. XP7OTO cells exhibited a twice higher sensitivity to 254 nm UV killing (n (extrapolation number) = 1.2, Do (mean lethal dose) = 2.2 J/m2) than did normal cells (n = 1.5, Do = 5.0 J/m2). The patient has, as yet, developed neither skin malignancies nor neurological abnormalities.
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PMID:Xeroderma pigmentosum complementation group E: a case report. 377 95

Twenty-six patients with xeroderma pigmentosum (XP), who live in the Northeast (Tohoku) District of Japan, were examined for the clinical characteristics of UV-induced DNA synthesis (unscheduled DNA synthesis, UDS) and UV sensitivity of skin fibroblasts or lymphoblastoid cells, or both. A history of consanguineous marriage within two generations was found in 19 of 26 cases (73%). Two pairs of siblings showed similar manifestations and almost the same levels of UDS and of UV sensitivity. Squamous cell carcinoma, basal cell carcinoma, or both were observed on the exposed skin in 14 patients, but no malignant melanoma was found. Cancer had developed in approximately 71% (10/14) of the cancer-bearing patients by the age of 20, and 8 of them belonged to the UDS-deficient group. Neurological manifestations were associated with nine patients, including 3 with typical de Sanctis-Cacchione syndrome (DSC), and most of the cells derived from these patients had a UDS level less than 10% of that of the normal cells. A clear correlation between the levels of UDS and UV sensitivity, on the one hand, and the severity of clinical manifestations on the other could not be detected, but it seems that the UDS-deficient group is generally much more sensitive to UV in terms of cell killing and the induction of sister chromatid exchange (SCE) than the UDS-proficient group. After a photosensitivity test, one patient with mild skin manifestations showed distinct skin tanning without preceding erythema.
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PMID:Clinical and biological studies of 26 cases of xeroderma pigmentosum in northeast district of Japan. 397 May 83

Instrumentation for studying action spectra in controls and various light-associated diseases is described. This study summarizes tests performed with a prism grating monochromator during the last 10 yr. There were 68 photodermatoses studied: xeroderma pigmentosum (XP) (1), lupus erythematosus (LE) (12), polymorphous light eruption (PLE) (23), solar urticaria (4), actinic reticuloid (2), halogenated salicylanilide photosensitivity and persistent light reactors (11), psoralen photosensitivity (6), and porphyria (9). A normal minimal erythema dose in the UVB (below 320 nm) was generally observed in polymorphous light eruption and lupus erythematosus. The most exquisite photosensitivity for delayed erythema was observed in actinic reticuloid, which in one case was 25-35 times more sensitive in the UVB range which was also observed but to a lesser extent in XP and in persistent light reactors. Persistence of erythema and edema at test sites was observed in XP, PLE, LE, and actinic reticuloid. A delay in development of erythema reaching a maximum at 72 hr was observed in XP and psoralen phototoxicity. Maximum photosensitivity occurred in solar urticaria. Three patients had peak sensitivity in the range of 310-313 nm and the 4th at 460 nm. Photosensitivity in the visible range was detected in 2 patients with solar urticaria, one with actinic reticuloid, and confirmed in 9 patients with porphyria (405 nm). Photosensitivity in the UVA (above 320 nm) occurred to some degree in all groups.
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PMID:Instrumentation and action spectra in light-associated diseases. 725 55

Clinical and photobiological differences between Japanese patients belonging to xeroderma pigmentosum (XP) variant and complementation group A were studied, especially focussing on XP variants. All of the XP variant patients commonly manifested a delayed onset of pigmented freckles as the initial symptom around 5--7 years old without acute sun erythema, in contrast to the early manifestation of acute solar erythema during infancy in XP group A patients. Six XP variant patients tested showed normal and three showed low minimal erythema doses (MEDs), at the 24 h reaction peak after monochromatic u.v. (280--330 nm) irradiation, while XP group A patients had definitely low MEDs (280--350 nm) with abnormally delayed peaking of the erythema reaction at 72 h. In cell culture studies, all XP variant strains exhibited normal levels of 254 nm u.v.-induced, unscheduled DNA synthesis (UDS), 1.4--2 times more accumulation of excision DNA breaks by arabinofuranosyl cytosine and hydroxyurea due to a subtle defect in the later polymerization step of excision repair, and a slightly higher sensitivity to u.v. cell killing than did normal cells. With respect to the synergistic effect of caffeine on u.v. lethality, XP variant strains could be divided into caffeine-susceptible (eight cases) and caffeine-resistant (two cases) subgroups. The extent of excision-break accumulation was greater in the former subgroup than in the latter. All of eight XP variant patients whose cells showed caffeine potentiation of u.v. lethality had already had skin malignancies, but two sib patients whose cells were caffeine-resistant had as yet had no neoplasm. It is strongly suggested that in XP variant, caffeine-susceptibility may be related to the development of neoplasms.
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PMID:Clinical and photobiological characteristics of Japanese xeroderma pigmentosum variant. 725 73


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