Bibliometric analysis of intestinal microbiota in diabetic nephropathy.

OBJECTIVE: The purpose of this study is to use bibliometrics to explore the research overview and research hotspots. MATERIALS AND METHODS: The relevant literature on intestinal flora and diabetic nephropathy in the Web of Science Core Collection was sorted out, and VOSviewer, CiteSpace, Scimago Graphica and other software were used to conduct data visualization analysis on the number of publications, countries, institutions, journals, authors, keywords and citations. RESULTS: A total of 124 relevant literatures were included. From 2015 to 2022, the number of published papers increased every year. The countries, institutions and journals that published the most articles in this field are China, Isfahan University Medical Science and Frontiers in Pharmacology. Liu Bicheng and Mirlohi Maryam are the authors with the most published articles in this field. The main keywords of research in this field are obesity, inflammation, oxidative stress, indoxyl sulfate, short-chain fatty acids (SCFAs) and Chinese herbal medicine. CONCLUSIONS: This is the first bibliometric analysis of diabetic nephropathy and gut microbiota, reporting hot spots and emerging trends. Obesity, inflammation, oxidative stress, indoxyl sulfate, SCFAs and Chinese herbal medicine are the main keywords of current research, and SCFAs and Chinese herbal medicine may be the hotspots of future research.

Quercetin Potentiates the NGF-Induced Effects in Cultured PC 12 Cells: Identification by HerboChips Showing a Binding with NGF.

Dementia is a persistent disorder of the mental processes and is strongly related to depression. However, the performance of current antidepression medicine is far from satisfactory. Herbal extract provides an excellent source to identify compounds for possible drug development against depression. Here, HerboChips were employed to search herbal compounds that could bind nerve growth factor (NGF). By screening over 500 types of herbal extracts, the water extract of Ginkgo Folium, the leaf of Ginkgo biloba, showed a strong binding to NGF. The herbal fractions showing NGF binding were further isolated and enriched. By using LC-MS/MS analysis, one of the NGF binding fractions was enriched, which was further identified as quercetin, a major flavonoid in Ginkgo Folium. Quercetin, similar to Ginkgo Folium extract, could enhance the effect of NGF in cultured PC 12 cells, including potentiation of neurite outgrowth and phosphorylation of Erk-1/2. This is the first report of discovering an NGF binding compound by using HerboChips from herbal extracts, which could be further developed for antidepression application.

[A review of Hirata Atsutane's Yi zong zhong jing kao (Studies on Zhongjing, the Medical Master)].

In the book named Yi zong zhong jing kao (Studies on Zhongjing, the Medical Master), through a series of examinations, the author, Hirata Atsutane of the late Edo period of Japan, argued that the author of the book Shang han lun (Treatise on Febrile Diseases) is Ge Xuan, brother of Ge Hong's grandfather, whereas the names of Dai Ba, Zhang Ji, Zhong Jing, etc., in ancient books are but his other names or his alias. With Ge Xuan as a basis, Hirata Atsutane explored its former and later history and eventually pointed out that medical prescriptions of traditional Chinese medicine were originally formulated by the gods, and fundamentally rooted from the Japanese gods, or called Shinto in ancient Japan, which is the foundation of Traditional Chinese Medical art. Prospectively, Hirata Atsutane's such conclusion is incredible. Actually, Hirata Atsutane used a series of textual investigation to interpret the doctrine of supernatural medicine, or the idea of "medical Shinto" he advocated. This thought also corresponds to the thinking of recede-to-ancient Shinto, reflecting his view of superiority of Japan over China. In a broader sense, such viewpoint on China can also be seen as a strong nationalist view in Japan, emphasized by the intelligentsia represented by classical scholars and even by Japan as a whole in the mid-late Edo period.

[Diagnosis and treatment of T1a-T1b prostate cancer].

OBJECTIVE: To explore the clinical pathological characteristics and improve the recognition in the diagnosis and treatment of incidental (stage T1a-T1b) prostate cancer. METHODS: Seven hundred and seventy-one patients who underwent TURP from May 2004 to September 2013 were analyzed retrospectively. In our institution, TURP specimens should be totally submitted in an extensive sampling method. The tumor area was outlined by estimation of an experienced genitourinary pathologist and calculated by the image analysis system software (Image J 1.47 h). The tumor area was then multiplied by the thickness of tissue. The total sum of all tumor volume was the estimated tumor volume. The clinical and pathological factors, follow-up results were obtained and we aimed to collect information about the period of watchful waiting (WW), PSA progression status, intervention status during the follow-up, the reason for intervention on WW and the type of intervention. RESULTS: The average age of 771 patients was (71.3±5.9) years old, and the average BMI was (23.9±3.1) kg/m2, preoperative average tPSA was (4.4±2.8) µg/L. Eighty-six (11.2%) cases of incidental prostate cancer were detected. The patients in T1a group (77 cases, 89.5%) had tumor volumes of (12.3±12.6) mm3, and the patients in T1b group had tumor volumes of (105.1±41.8) mm3.The range of tumor volume was 0.4-180.2 mm3. The volume of all the 86 cases was less than 500 mm3 as the threshold of insignificant cancer. All the patients were managed by WW. The mean follow-up time was 88.9 (27.9-150.1) months.The Gleason score was <7 in 79 patients, and ≥7 in 7 patients. There was no significant difference in age, preoperative tPSA, preoperative PSAD, postoperative tPSA, prostate volume and TURP resection between T1a group and T1b group (P>0.05). Among 84 patients without follow-up losts, PSA progression occurred in 5 patients. One T1a patient underwent radical prostatectomy (RP) as an intervention, and 3 patients underwent hormone therapy. One patient in T1b group underwent radiotherapy for PSA progression and one was treated because of patient preference without evidence of disease progression. There were no patients who died due to prostate cancer. CONCLUSION: Eighty-six (11.2%) cases of incidental prostate cancer were detected. The tumor volume of all the cases was insignificant cancer.The clinical outcomes of IPCa were satisfactory with the initial treatment of WW in the Chinese population.

Dexamethasone alone vs in combination with transcutaneous electrical acupoint stimulation or tropisetron for prevention of postoperative nausea and vomiting in gynaecological patients undergoing laparoscopic surgery.

BACKGROUND: Postoperative nausea and vomiting (PONV) is commonly reported after surgery and anaesthesia. We compared the effects of combinations of electrical acupoint stimulation or tropisetron with dexamethasone with the effects of dexamethasone alone, for inhibition of PONV in gynaecological patients undergoing laparoscopic surgery. METHODS: We randomized 157 patients undergoing elective gynaecological laparoscopic surgery under general anaesthesia into the following three groups: acupoint stimulation+dexamethasone (Group Acu, n=53), tropisetron+dexamethasone (Group Trp, n=53), and dexamethasone alone (Group Dxm, n=51). The incidence of nausea, vomiting, and need for rescue antiemetics was recorded 2, 6, 24, and 48 h after surgery. RESULTS: We found significant differences in the incidence of PONV during 24 h after surgery between the combination therapy groups and the dexamethasone-alone group (P=0.021). In the first 24 h, 28% of patients in Group Acu, 26% of patients in Group Trp, and 50% of patients in Group Dxm experienced nausea, vomiting, or both. The incidence of 24 h PONV in Group Acu was significantly lower than that in Group Dxm (P=0.048; odds ratio 0.389; 95% CI 0.170-0.891). The incidence of 24 h PONV in Group Trp was also significantly lower than that in Group Dxm (P=0.042; odds ratio 0.359; 95% CI 0.157-0.819). There was no significant difference between Group Acu and Group Trp (P=0.857). The need for antiemetic rescue medication was similar in the three groups. All groups expressed similar patient satisfaction. CONCLUSIONS: Combined with dexamethasone, electrical acupoint stimulation or tropisetron is more effective in PONV prophylaxis than dexamethasone alone in gynaecological patients undergoing laparoscopic surgery. CLINICAL TRIAL REGISTRATION: NCT 02096835.

High-resolution anorectal manometry in newborns: normative values and diagnostic utility in Hirschsprung disease.

BACKGROUND: Conventional methods of screening for Hirschsprung disease (HD) in newborns (barium enema, BE; anorectal manometry, ARM; rectal suction biopsy, RSB) have limitations and/or are invasive. High-resolution anorectal manometry (HR-ARM) is a minimally invasive technique that has potential to overcome most of these limitations, but normative data and performance characteristics have not been reported in newborns. The aims of our study were to assess anorectal sphincter metrics including resting pressure (RP), anal canal length (ACL), and rectoanal inhibitory reflex (RAIR) in healthy and asymptomatic newborns, and to explore the role of HR-ARM in the diagnosis of HD using these normal parameters. METHODS: All procedures were performed using solid state HR-ARM equipment (Medical Measurement Systems, Enchede, The Netherland) by a single operator. In the first phase, 180 asymptomatic newborns (term newborns 95, preterm newborns 85) were studied, and anal RP, ACL, and RAIR were measured. In the second phase, 16 newborns with clinical manifestations of HD were studied (9 of whom had histopathologic confirmation), and parameters compared to asymptomatic newborns. KEY RESULTS: Normative RP values were higher in term newborns compared with preterm newborns (p < 0.05), and correlated with age. Progressive maturation of the anal sphincter was evident with chronologic age, both in preterm and term newborns. RAIR was present in all normal subjects. Using absent RAIR as indicative of HD, HR-ARM had a sensitivity 89% and specificity of 83% compared to RSB; these performance characteristics were better than BE (sensitivity 78%, specificity 17%), with significantly higher diagnostic accuracy (80% vs 53%, respectively, p = 0.009). CONCLUSIONS & INFERENCES: Anorectal sphincter pressure progressively matures with incremental increase in RP during the first months of life. HR-ARM is an effective and safe method that complements the diagnosis of HD in newborns.

First Report of Fusarium solani Causing Root Rot on Coptis chinensis in Southwestern China.

China is the world's largest producer country of coptis (Coptis chinensis), the rhizomes of which are used in traditional Chinese medicine. Since 2008, however, root rot symptoms, including severe necrosis and wilting, have been observed on coptis plants in Chongqing, southwestern China. Of the plants examined from March 2011 to May 2013 in 27 fields, 15 to 30% were covered with black necrotic lesions. The leaves of infected plants showed wilt, necrotic lesions, drying, and death. The fibrous roots, storage roots, and rhizomes exhibited brown discoloration and progressive necrosis that caused mortality of the infected plants. Infected plants were analyzed to identify the causal organism. Discoloration of the internal vascular and cortical tissues of the rhizomes and taproots was also evident. Symptomatic taproots of the diseased coptis were surface sterilized in 1% sodium hypochlorite for 2 min, rinsed in sterile distilled water for 2 min, and then air-dried in sterilized atmosphere/laminar flow. Small pieces of disinfested tissue (0.3 cm in length) were transferred to petri dishes containing potato dextrose agar (PDA) supplemented with 125 µg ml-1 streptomycin sulfate and 100 µg ml-1 ampicillin, and incubated for 5 days at 25°C with a 12-h photoperiod. Four distinct species of fungal isolates (HL1 to 4) derived from single spores were isolated from 30 plants with root rot symptoms collected from the study sites. To verify the pathogenicity of individual isolates, healthy coptis plants were inoculated by dipping roots into a conidial suspension (106 conidia/ml) for 30 min (15 plants per isolate), as described previously (1). Inoculated plants were potted in a mixture of sterilized quartz sand-vermiculite-perlite (4:2:1, v/v) and incubated at 25/18°C and 85 to 90% relative humidity (day/night) in a growth chamber with a daily 16-h photoperiod of fluorescent light. Plants dipped in sterile distilled water were used as controls. After 15 days, symptoms similar to those observed in the field were observed on all plants (n = 15) that were inoculated with HL1, but symptoms were not observed on plants inoculated with HL2, HL3, and HL4, nor on control plants. HL1 was re-isolated from symptomatic plants but not from any other plants. Morphological characterization of HL1 was performed by microscopic examination. The septate hyphae, blunt microconidia (2 to 3 septa) in the foot cell and slightly curved microconidia in the apical cell, and chlamydospores were consistent with descriptions of Fusarium solani (2). The pathogen was confirmed to be F. solani by amplification and sequencing of the ribosomal DNA internal transcribed spacer (rDNA-ITS) using the universal primer pair ITS4 and ITS5. Sequencing of the PCR product revealed a 99 to 100% similarity with the ITS sequences of F. solani in GenBank (JQ724444.1 and EU273504.1). Phylogenetic analysis (MEGA 5.1) using the neighbor-joining algorithm placed the HL1 isolate in a well-supported cluster (97% bootstrap value based on 1,000 replicates) with JQ724444.1 and EU273504.1. The pathogen was thus identified as F. solani based on its morphological and molecular characteristics. To our knowledge, this is the first report of root rot of coptis caused by F. solani in the world. References: (1) K. Dobinson et al. Can. J. Plant Pathol. 18:55, 1996. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Oxford, 2006.

Tanshinone-1 induces tumor cell killing, enhanced by inhibition of secondary activation of signaling networks.

Tumor multidrug resistance (MDR) can result from overexpression of drug transporters and deregulation of cellular signaling transduction. New agents and strategies are required for overcoming MDR. Here, we report that tanshinone-1, a bioactive ingredient in traditional Chinese medicine, directly killed MDR tumor cells and their corresponding parental cells, which was potentiated by inhibition of secondary activation of signaling networks. Tanshinone-1 was slightly more potent at inducing cytotoxicity and apoptosis in MDR cells than in corresponding parental cells. Tanshinone-1-induced MDR cell killing was independent of the function and expression of drug transporters but was partially correlated with the phosphatase-dependent reduction of phospho-705-Stat3, which secondarily activated p38-, AKT-, and ERK-involved signaling networks. Cotreatments with p38, AKT, and ERK inhibitors potentiated the anti-MDR effects of tanshinone-1. Our study presents a model for MDR cell killing using a compound of natural origin. This model could lead to new therapeutic strategies for targeting signaling network(s) in MDR cancers as well as new strategies for multitarget design.

Medicinal herbs for esophageal cancer.

BACKGROUND: Esophageal cancer is the seventh leading cause of cancer death worldwide. Traditional Chinese medicinal herbs are sometimes used as an adjunct to radiotherapy or chemotherapy for this type of cancer. OBJECTIVES: To assess the efficacy and possible adverse effects of the addition of Chinese medicinal herbs to treatment with radiotherapy or chemotherapy for esophageal cancer. SEARCH STRATEGY: We searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register, The Cochrane Library, MEDLINE, EMBASE, AMED (Allied and Complementary Medicine Database), CBM (Chinese Biomedical Database), China National Knowledge Infrastructure, the Chinese Cochrane Centre Controlled Trials Register and CISCOM (The Research Council for Complementary Medicine) (up to June 2004). Databases of ongoing trials, the internet and reference lists were also searched. SELECTION CRITERIA: Randomised controlled trials comparing the use of radiotherapy or chemotherapy with and without the addition of Chinese medicinal herbs. DATA COLLECTION AND ANALYSIS: At least two review authors extracted data and assessed trial quality. MAIN RESULTS: Two studies were included. The numbers of participants in these two trials were 42 and 80, 122 in total. Both studies were analysed separately because of the differences in interventions used. Although one study reported a positive result, the majority of outcome measurements from the two studies showed no significant benefit with the addition of Chinese herbal medicines to radiotherapy or chemotherapy. There was statistically significant improvement in quality of life with the additional Huachansu injection, however, no statistically significant improvement was found in short-term therapy effects, one-year survival rate or the adverse effect of radiation-induced esophagitis. AUTHORS' CONCLUSIONS: The included studies were of low quality. The results suggest Zhenxiang capsules or Huachansu injection may not improve short-term therapy effects or one-year survival rate when used as adjunct treatment to chemo- or radiotherapy in the treatment of esophageal cancer. The quality of life may be improved by Huachansu injection. The results suggest that more high-quality trials on Huachansu injection and other Chinese herbal medicines are needed in the future.

Thermal characteristics of microwave ablation in the vicinity of an arterial bifurcation.

PURPOSE: The objective of this research was to reveal the thermal characteristics of microwave ablations in the vicinity of an arterial bifurcation. METHODS: The temperature distribution after microwave heating of a liver-like material in the close proximity of an arterial bifurcation was simulated using the finite element method. Coupled fluid flow and solid heat transfer were taken into consideration and a three-dimensional analysis was performed. An experimentally determined SAR (specific absorption rate) generated by the absorption of microwaves in liver-like material was used in the analysis instead of utilizing electromagnetic calculations. Several different tests of time-controlled ablations with varying distances between the microwave antenna and the bifurcation were performed and detailed temperature distributions near the bifurcation were obtained. RESULTS: The interaction between the recirculation flow in the bifurcation and the heat transfer in the surrounding tissue makes the temperature distribution near the bifurcation complicated. Most importantly, after a period of continuous heating with constant microwave output power, the maximum temperatures caused by the ablation did not always increase with the distance between the antenna and the bifurcation. CONCLUSION: It can be concluded that inadequate ablations can be the result not only from a close proximity between the antenna and the blood vessel, but also from a complicated blood flow in large vessels whose structure causes recirculation flow.

Protective effects of Ginkgo biloba extract on cultured rat cardiomyocytes damaged by H2O2.

AIM: To investigate the influence of Ginkgo biloba extract (GbE) on cardiomyocytes damaged by H2O2. METHODS: Cultured rat cardiomyocytes were divided into 3 groups randomly: control group; H2O2 (2.5 mmol.L-1) group; H2O2 2.5 mmol.L-1 + GbE 150 mg.L-1 group. The cardiomyocytes were cultured in MEM (Eagle's) at 37 degrees C in the presence of 5% CO2 for 4 h. Lactate dehydrogenase (LDH) was assayed by colorimetric method. Lipid peroxidation was determined by measuring thiobarbituric acid-reactive substances. Ultrastructure was viewed under transmission electron microscope. RESULTS: Compared with the control group, LDH leakage and malondialdehyde (MDA) content increased in H2O2 group, LDH increased from (2166 +/- 247) U.L-1 to (5180 +/- 648) U.L-1, MDA increased from (3.5 +/- 0.2) nmol/10(6) cells to (7.2 +/- 0.4) nmol/10(6) cells (P < 0.01). The ultrastructure was damaged seriously. GbE inhibited the increase of LDH leakage and MDA content induced by H2O2. In this group, LDH decreased from (5180 +/- 648) U.L-1 to (3496 +/- 386) U.L-1, MDA decreased from (7.2 +/- 0.4) nmol/10(6) cells to (4.8 +/- 0.9) nmol/10(6) cells (P < 0.01). Ultrastructure of cells was also protected by GbE. CONCLUSION: GbE protected the cardiomyocyte against H2O2 injury, the protective action was attributed to its antiperoxidative effect.

Expression of a 91-kilodalton PEA3-binding protein is down-regulated during differentiation of F9 embryonal carcinoma cells.

Proteins binding to the PEA3 enhancer motif (AGGAAG) activate the polyomavirus early promoter and help comprise the viral late mRNA initiator element (W. Yoo, M. E. Martin, and W. R. Folk, J. Virol. 65:5391-5400, 1991). Because many developmentally regulated cellular genes have PEA3 motifs near their promoter sequences, and because Ets family gene products activate the PEA3 motif, we have studied the expression of PEA3-binding proteins and Ets-related proteins during differentiation of F9 embryonal carcinoma cells. An approximately 91-kDa protein (PEA3-91) was identified in F9 cell nuclear extracts by UV cross-linking to a radiolabeled PEA3 oligonucleotide probe, and expression of PEA3-91 was down-regulated after differentiation of F9 cells to parietal endoderm. The c-ets-1 gene product binds to a sequence in the murine sarcoma virus long terminal repeat that is similar to the PEA3 motif (cGGAAG), but PEA3-91 was not cross-linked to this Ets-1-binding motif, nor did antiserum which recognizes murine c-ets-1 and c-ets-2 proteins have any effect on PEA3-binding activity in mobility shift assays. Furthermore, c-ets-1 mRNA was not detected in undifferentiated or differentiated F9 cells, and c-ets-2 mRNA levels remained high after differentiation. Antiserum against the Drosophila Ets-related E74A protein, however, recognized an approximately 92-kDa protein in F9 cells whose expression during differentiation varied in a manner identical to that of PEA3-91. These data suggest that PEA3-91 is not the product of the ets-1 or ets-2 genes but is likely to be the product of a murine homolog of the Drosophila E74 gene.

[Antiarrhythmic effects of kappa-seleno-carrageenan in experimental animals].

The effect of Kappa-seleno-carrageenan, an organic compound containing selenium, on aconitine, BaCl2 and ouabain-induced arrhythmias were studied. When rats were given ip 9 mg.kg-1.d-1 x 5 d or ig single dose of 35, 70, 140 mg.kg-1, the threshold dose of aconitine was elevated significantly to induce HA. The effect seems to resemble that of ip Na2SeO3 1 mg.kg-1 x d-1 x 5 d. With increasing ig dose, the threshold dose of aconitine was elevated for inducing VE, VT, VF. When ip 9 mg.kg-1 x d-1 x 5 d or ig 70 mg.kg-1 was given, the threshold doses of BaCl2 in inducing VF (in rats) and ouabain in inducing VE (in guinea-pig) were elevated. However, no influence was observed for ip Na2SeO3 1 mg.kg-1 x d-1 x 5 d.

New refractive method for laser thermal keratoplasty with the Co:MgF2 laser.

We have observed corneal curvature changes from laser thermal keratoplasty with a Co:MgF2 laser. We studied corneal curvature changes in rabbits and have identified specific treatment patterns and laser parameters that can correct myopia and astigmatism. These corneal changes, some as large as 8 diopters, have been stable for at least one year, and slitlamp examination demonstrates clear central corneas with normal appearance.

Effect of astragalus membranaceus on electric activities of cultured rat beating heart cells infected with Coxsackie B-2 virus.

Astragalus membranaceus (AM) which has a protective effect on rat beating heart cells infected experimentally with Coxsackie B-2 virus was evaluated on the basis of changes in morphologic and electric activity of the cells. Rhythm, beating frequency, beating percentage, cardiac cellular damage and cytopathic effects (CPE) were monitored every 24 h after challenge; electric activities parameters were measured by conventional intracellular microelectrode technique. Significant protective effects were demonstrated when AM was given in the early period of infection. The results suggest that AM should be valuable in preventing and treating acute myocarditis caused by Coxsackie B virus.

[Evaluation of hysterography in the diagnosis of choriocarcinoma and invasive mole].

From 1963 through 1985, 181 hysterography were performed for 101 patients. The diagnostic accuracy of hysterography was 92.3%. There were no false positive findings, though a negative result may be obtained in patients whose intramural lesion does not communicate with the uterine cavity, as proved by operative findings. Three types of abnormalities were observed on the hysterogram: (1) filling defect, (2) intramural invasion of the uterine wall by the contrast medium and (3) extravasation of the contrast medium into the pelvic veins. The filling defect was usually observed in patients with (1) residual molar tissue in the uterine cavity, (2) intramural lesion and (3) intrauterine adhesions. The above three conditions can be differentiated by the characteristic shape of the filling defect. If it is used in combination with either or both of the other two procedures, ie., B-ultrasound and pelvic arteriography the accuracy of diagnosis will be further improved.

The use of Chinese herb medicine in experimental radiotherapy.

Extracts from a group of destagnative herbs, 764-1, and the effective chemical, 764-3, were tested by an in vitro experiment using a HeLa-S3 cell line. Under aerobic conditions, the shoulder of the cell survival curve diminished or disappeared according to the different doses of 764-1 used, but no change in slope was observed. In nitrogen, when the dose of 764-1 increased to 20 mg/ml (ID20), besides the disappearance of the shoulder, the slope of the curve also showed changes at lower doses (4-8 Gy); up to 10-25 Gy the curve became more flattened. 764-3 showed almost a similar effect by mainly affecting the shoulder of the survival curve. At low drug doses a SER as high as 1.87 might be obtained under hypoxic condition. At the same time 764-1 was used in testing the effect on radiation lung damage. It was found that 764-1 could markedly inhibit the change of alveolar surfactant at 1 and 3 weeks after radiation. A wide field of investigation is thus spread out in front of us on radiosensitization and protection. Further studies on 764-3 are carried out.

8-Methoxypsoralen-DNA adducts in patients treated with 8-methoxypsoralen and ultraviolet A light.

The combination of 8-methoxypsoralen (8-MOP) plus ultraviolet A light (320-400 nm), termed PUVA, is used in the treatment of psoriasis, a hyperproliferative disease of the skin. This treatment results in the formation of specific 8-MOP adducts with cellular DNA. We have previously developed monoclonal antibodies which recognize these 8-MOP photoadducts. We now report the use of these antibodies in an indirect immunofluorescence technique to study human skin biopsies. Nuclei in 3 of 5 skin biopsies from psoriasis patients undergoing PUVA therapy were positive for adducts. The presence of adducts by immunofluorescence did not correlate with plasma levels of 8-MOP. Enzyme-linked immunosorbent assays, used to determine whether 8-MOP photoadducts could be detected in DNA isolated from the lymphocytes of psoriasis patients after PUVA therapy, were negative.

Effects of 8-methoxypsoralen and ultraviolet light A on EGF receptor (HER-1) expression.

Activation of psoralens by ultraviolet light irradiation at 308-400 nm (UVA) is used in the photochemical treatment of psoriasis. While the major effect of this activation is the formation of DNA adducts, it was recently demonstrated that psoralens can also bind to specific saturable high affinity cellular receptors, and that this is associated with inhibition of epidermal growth factor (EGF)-receptor binding. In view of these findings, we have examined whether 8-methoxy-psoralen (8-MOP) itself, or in combination with UVA, influences expression of the human EGF-receptor gene ("HER-1") in a human keratinocyte cell line. We have found that 8 MOP alone, and to a lesser extent UVA, induce a striking increase in cellular levels of HER-1 RNA. The combination of 8-MOP with UVA produces less induction of HER-1 RNA than that obtained with 8-MOP alone. We suggest, therefore, that this effect of 8-MOP is not due to DNA damage, but may reflect a separate effect of this compound on receptor-mediated signal transduction.

Detection and quantification of 8-methoxypsoralen-DNA adducts.

8-Methoxypsoralen (8-MOP) is a photoactivated drug used clinically in the treatment of psoriasis and cutaneous T-cell lymphoma (CTCL). We have developed monoclonal antibodies which specifically recognize 8-MOP-modified DNA and do not cross-react with unmodified DNA or free 8-MOP. Highly sensitive, competitive enzyme-linked immunosorbent assays (ELISA) have been developed with both colour and fluorescence endpoint detection for quantification of DNA adducts in biological samples. In addition, immunofluorescence and flow cytometric techniques have been developed to visualize adducts in tissues and cells. These techniques have been validated in keratinocytes treated in culture and in animals treated in vivo with 8-MOP and ultraviolet A (UVA) light. Adduct levels have also been monitored in skin biopsies and lymphocytes of patients with psoriasis and lymphoma.