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101.
BACKGROUND: Although phototherapeutic modalities are commonly used for the treatment of skin diseases, the effects of therapeutic ultraviolet (UV) irradiation on the dermoscopic appearance of melanocytic naevi are unknown. OBJECTIVES: We aimed to analyse the effects of photochemotherapy (psoralen plus ultraviolet A, PUVA) and narrow-band ultraviolet B phototherapy (NB-UVB) on the dermoscopic appearance of naevi. PATIENTS AND METHODS: We monitored 187 melanocytic naevi of 38 patients receiving NB-UVB or PUVA treatment for miscellaneous skin diseases. Dermoscopic images of naevi were taken before, shortly after, and after a median of 31 weeks after the UV therapy. A random selection of naevi was covered during UV treatment, the others remained uncovered. Baseline and follow-up images of naevi were viewed side by side on a computer screen to compare size, pigmentation, and dermoscopic structure of naevi. RESULTS: Twenty-one patients received NB-UVB treatment, and 17 patients received PUVA treatment. Of 187 naevi, 70 (37%) were covered and 117 (63%) were uncovered during UV treatment. When NB-UVB- and PUVA-treated patients were analysed together, an increase in size of uncovered lesions was seen in both treatment groups. Pigmentation appeared darker at the end of UV treatment in 67.5% (n=79) of uncovered naevi compared with 41.4% (n=29) of covered naevi (P<0.001). In patients receiving NB-UVB therapy, a significant increase in the number of dots or globules in 20.3% (n=14) of uncovered naevi compared with only 5.0% (n=2) of covered naevi (P=0.03) was found. This effect was not observed after PUVA therapy. With the exception of four naevi with continuous enlargement and seven naevi with a persisting increase in dots and globules, the observed changes were reversible. All naevi with persistent changes belonged to the NB-UVB group. CONCLUSION: In general, PUVA and NB-UVB therapy cause reversible dermoscopic changes in melanocytic naevi. Increase in dots and globules is more frequent with NB-UVB.  相似文献   
102.
Summary. The amount of membrane-associated glycoprotein Ib in platelet concentrates (PCs) irradiated with a high dose of UVB light has been shown to be significantly reduced after 48 h storage. We recently corroborated this finding when we noted an increase in the supernatant levels of glycocalicin (GC, a major segment of glycoprotein Ib) in UVB-treated PCs during storage. The aim of the present study was to determine whether GC release was related to both the UV dose and the rate of dose delivery. Plateletpheresis concentrates obtained from five donors were pooled and split into five equal parts. Four of these were treated with 7500 and 15000 mJ/cm2 UVB using two prototype UV sources with differing rates of dose delivery; namely, Baxter (BAT) and British Aerospace (BAC) cabinets, with the latter having the slower rate of delivery. On days 1 and 5 of storage, GC levels in the supernatants of PCs were determined by ELISA. Moreover, the following parameters were also assessed: platelet and WBC count; hypotonic shock response (HSR) and platelet aggregation response to ADP, ADP +collagen, ADP + arachidonic acid and ristocetin; pH; supernatant levels of lactate, glucose, von Willebrand factor (vWf) and β-thrornboglobulin (βTG). The results revealed an association of GC release with UVB dose using both UV sources, although this was more apparent in the BAC system, in which glycocalicin release at day 5 of storage was as follows (μg/ml, mean ± SD): 4·8±0·3 and 9·5±3·6 at 7500 and 15000 mJ/cm2 respectively. Moreover, at 15000 mJ/cm2, PCs treated in the BAC system exhibited significantly higher levels of GC than those treated in the BAT system: 9·5±3·6 and 4·8± 3·6 respectively at day 5 of storage (P= 0·05). This differential GC increase in the BAC was coupled with a decrease in HSR and a significant increase in lactate and βTG levels compared with the BAT system. In contrast to the GC results, vWf supernatant levels in PCs treated with UVB were decreased relative to non-treated PCs of the same origin. Moreover, GC release correlated significantly with various standard tests of platelet function indicating its importance as a quality indicator for the investigation of the platelet storage lesion. Our results show that UVB not only increases GC release in a dose/rate-dependent manner but that it may also affect the quality of irradiated PCs and their shelf life.  相似文献   
103.
The ultraviolet (UV) light spectrum has long been known to induce biologic effect on the skin. For a large number of cutaneous disorders, phototherapy and photochemotherapy are effective therapeutic options with excellent safety profiles and well-documented side effects. Despite their ease of administration and benefits, phototherapeutic treatment modalities require appropriate space for the equipment, trained staff, and patient education prior to initiating treatment. However, when the initial barriers to treatment can be overcome, UV therapy can offer patients significant relief from their cutaneous disease. Furthermore, UVB-based phototherapy can produce significant alteration to vitamin D levels. With the recent research implicating association of low vitamin D levels with a variety of health conditions, whether patients receiving phototherapy or, more specifically, those getting vitamin D supplement may be protected from these diseases remains to be established.  相似文献   
104.
目的 观察口服疏肝活血中药联合窄谱中波紫外线照射治疗气滞血瘀型白癜风方面的疗效和安全性。方法 将90 例白癜风患者随机分为联合组、光疗组及中药组,每组各30 例。联合组口服该院舒肝活血中药配方颗粒,2 次/d。并且用311 nm 窄谱中波紫外光照射治疗,每周照射1、2 次。光疗组:照射311 nm 窄谱中波紫外光,每周照射1、2 次。中药组:口服该院疏肝活血中药配方颗粒,2 次/d。每3 个月进行1 次白癜风白斑复色率疗效评价、中医证候评分改善疗效评价及肝肾功能评测。共观察3 个疗程。结果联合组白斑疗效总有效率均高于光疗组和中药组(P <0.05);疗效与患者白斑部位、病程有相关性,与患者年龄无相关性;联合组中医证候改善总有效率均高于光疗组,与中药组无差异(P >0.05)。结论 应用疏肝活血法联合窄谱中波紫外光治疗气滞血瘀型白癜风能获得满意疗效,可在临床推广应用。  相似文献   
105.
Hydrocortisone 21-acetate (HCA) in methanol solution undergoes photodegradation under UVB light, as monitored by HPLC. Five main photoproducts have been isolated and characterized by means of NMR and mass spectroscopy. One of them derives from a Norrish I photoreaction which cleaves the C17-C20 bond of the steroid yielding the andro-derivative, a second product comes from a Yang-type photorearrangement which links C18 to C20 yielding a cyclobutane adduct. The former photoproduct, in turn, undergoes further photolysis giving rise to various photoproducts, of which three have been characterized. The first is a stereoisomer of the andro-derivative, the others arise from the opening of the five-membered ring. HCA also proved photounstable in the solid state and in a commercial formulation for topical use, thus confirming the requirements of the Pharmacopeias for light protection of this drug. Indeed, experiments on LPS-stimulated THP-1 cells demonstrated the loss of anti-inflammatory activity when HCA was UVB-photodegraded. The radical mechanism involved in HCA photolysis seems also responsible for the in vitro photohemolytic effect and lipid peroxidation induced by HCA in combination with UVB light.  相似文献   
106.
Many authors currently advocate 10-20% dosage increments between phototherapy sessions when treating psoriasis with narrowband ultraviolet B (UVB). However, such regimens are associated with a risk of significant erythema. In order to reduce this risk, a fixed increment regimen was developed using increments ranging from 30 mJ/cm2 for skin type II to 150 mJ/cm2 for type VI. Starting doses, also based on skin type, range from 180 to 400 mJ/cm2. Data from 20 patients with moderate to severe plaque psoriasis [13 male, 7 female, age range 17-74, skin types II (3), III (10), IV (3), V (1), VI (3)] completing 27 courses of phototherapy of more than 3 weeks' duration between 8/96 and 12/97 were compared. Complete, or near-complete clearing occurred in 8/13 courses (62%) with a frequency of attendance (during the initial 24 sessions) of >2.5 sessions per week, 4/8 (50%) with a frequency of 2.0-2.5, and 1/6 (17%) with a frequency of <2.0. In the subset of patients taking low-dose oral retinoids, rates of clearing were higher. Overall, 10 of 20 patients (50%) cleared, usually within 24-30 sessions. The average maximum dosage in such cases was 1400 mJ/cm2. There were only 13 instances of minor erythema, and 1 instance of severe erythema resulting in desquamation and requiring interruption of treatment. This was due to the inadvertent administration of an excessive 300 mJ/cm2 increment to a type VI patient. In summary, using a conservative fixed increment regimen, clearing of psoriasis is possible while minimizing the risk of serious erythema. Results are enhanced when patients attend 3 phototherapy sessions per week.  相似文献   
107.
108.
目的:观察健脾祛湿汤联合NB-UVB治疗慢性湿疹的临床疗效。方法:80例确诊患者,随机分为2组各40例,对照组以NB-UVB治疗;治疗组在对照组基础上加用健脾祛湿汤,每日1付,水煎服。2组均为10d1个疗程,治疗60d后统计疗效。结果:治疗组有效率为97.5%,对照组为80.0%,两组比较差异有统计学意义(P〈0.05)。结论:健脾祛湿汤联合NB-UVB治疗慢性湿疹安全有效。  相似文献   
109.
110.
Dermal synthesis, following sun exposure, is the main source of vitamin D. This study characterizes ambient UVB radiation relevant for vitamin D production in Europe. A biological weighing function was applied to data from the Tropospheric Emissions Monitoring Internet Service (TEMIS) for 46 capital cities over an 18-year period (2004–2021) to isolate wavelengths relevant for vitamin D production (D-UVB). Cumulative and weighted D-UVB (CW-D-UVB) were calculated to approximate seasonal vitamin D accumulation and diminution. Monthly 25(OH)D concentration measurements were extracted from published reports. All data were analyzed by location and time. Despite a moderate latitudinal range (35–64° N), we observed large—up to five-fold—regional differences: the highest mean diurnal D-UVB dose of 5.57 kJ/m2 (SD = 3.55 kJ/m2) was observed in Nicosia (Cyprus) and the lowest in Reykjavik (Iceland, 1.16 ± 1.29 kJ/m2). Seasonal differences in diurnal D-UVB dose were even more pronounced, with a median 36-fold difference between annual peak and trough depending on a location (range: 10- to 525-fold). The mean duration of “vitamin D winter” was 126 days but varied widely (4 to 215 days). Monthly CW-D-UVB and 25(OH)D changes were very strongly correlated: the changes in 25(OH)D concentration increased by 12.6 nmol/L for every 100 kJ/m2 increment of CW-D-UVB in population-based studies (r2 = 0.79, p-value = 1.16 × 10−37). Understanding the differences in D-UVB radiation can help understand determinants of vitamin D status and guide region- and season-specific safe and effective sunlight exposure recommendations and vitamin D supplementation guidelines.  相似文献   
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