Development of a whole-cell biosensor for detecting organophosphorus pesticide methyl parathion in the farmland soil / 生物工程学报

The evaluation of the bioavailability of pollutants in soil is crucial to accurately assess the pollution risk, and whole-cell biosensor is one of the important tools for such evaluation. This study aimed to develop a novel whole-cell biosensor for the detection of methyl parathion in soil using. First, a whole-cell biosensor was constructed by the screened methyl parathion hydrolase mpd gene, the existing specific induction element pobR, and the pUC19 plasmid skeleton. Then, the detection method of methyl parathion in soil extracts was established using 96-well microtiter plate as carrier and five whole-cell biosensors as indicator. The method was applied in the detection of methyl parathion in tested and field soil extracts. Taking E. coli DH5α/pMP-AmilCP with the best detection performance as an example, this biosensor had a detection limit of 6.21-6.66 µg/L and a linear range of 10-10 000 µg/L for methyl parathion in four soil extracts. E. coli DH5α/pMP-RFP and E. coli DH5α/pMP-AmilCP methods have good detection performance for the analysis of methyl parathion in soil extract samples. This biosensor method can help to quickly assess the bioavailability of methyl parathion in soil, and thus help to understand the risk of soil pollution caused by organophosphorus pesticide methyl parathion.

Molecular modeling, synthesis, and evaluation of 1-(4-methoxybenzofuran-5-yl)-3-phenylpropane-1, 3-dione for its anxiolytic potentiality

The disabling mental illness anxiety is gradually affecting the modern society in any age group worldwide. The searchfor novel bioactive entity from herbal origin for different disorders has become the center of attraction significantlyfrom the past few decades. Gamma-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter known tobe responsible for the anxiolytic activity of most of the potent anxiolytic agents. All the available data of pongamol1-(4-methoxybenzofuran-5-yl)-3-phenylpropane-1, 3-dione (MPD) were based on natural or semi-synthetic source.The synthetic routes were using easily available source and quick, cost-effective, and high yielding process. MPD hastraditionally been acquired from natural sources mainly from the extracts of fruits of Pongamia pinnata and Pongamiaglabra, where the yield value and the yield time are the main drawbacks. Keeping in view of the above aspects in thepresent research, it was approached to synthesize and evaluate the anxiolytic potential 1-(methoxybenzofuran-5yl)-3-phenylpropane-1, 3-dione on experimental animals and docking procedure after its synthesis. The study of MPDon the gross behavior of mice showed a significant Central Nervous System (CNS) depressant effect. Furthermore,its anxiolytic activity was confirmed by observing its reduced locomotion of mice using actophotometer and elevatedplus-maze apparatus. The highest docking score was observed to be −3.22 than the diazepam (−3.21) against GammaAmino Butyric Acid-A (GABAA). The present study provides a promising anxiolytic agent, MPD, which has itspotency due to the GABAA receptor binding and causing the mitigation of the symptoms of anxiety.

Lateral transfer of organophosphate degradation (opdopd) genes among soil bacteria: mode of transfer and contributions to organismal fitness

Genes encoding structurally independent phosphotriesterases (PTEs) are identified in soil bacteria. These pte genes, often identified on mobilizable and self-transmissible plasmids are organized as mobile genetic elements. Their dissemination through lateral gene transfer is evident due to the detection of identical organophosphate degradation genes among soil bacteria with little orno taxonomic relationship. Convergent evolution of PTEs provided selective advantages to the bacterial strain as they convert toxic phosphotriesters (PTs) into a source of phosphate. The residues of organophosphate (OP) compounds that accumulate in a soil are proposed to contribute to the evolution of PTEs through substrate-assisted gain-of-function. This review provides comprehensiveinformation on lateral transfer of pte genes and critically examines proposed hypotheses on their evolution in the light of the short half-life of OPs in the environment. The review also proposes alternate factors that have possibly contributed to the evolution and lateral mobility of PTEs by taking into account their biology and analyses of pte genes in genomic and metagenomic databases.

Functional diversity and functional traits of periphytic algae during a short-term successional process in a Neotropical floodplain lake / Diversidade funcional e características funcionais de algas perifíticas em um curto processo successional em um lago de planície de inundação Neotropical

AbstractDue to the lack of knowledge in periphytic algae functional diversity patterns during successional processes in floodplains, the present study aimed to analyze the dynamics of the functional traits and functional diversity of periphytic species during a short-term successional process in a floodplain lake. The functional traits analyzed were size class, growth form, strength of attachment to the substratum, and functional strategies. We evaluated the dynamics of these traits, considering richness, density and biovolume during an 18-day colonization in two hydrological periods. The functional diversity was assessed using the mean pairwise distance index (MPD). Dominant functional traits during the colonization changed in association with the flood pulse. Under the pulse effect, higher development of C-S strategist, loosely attached, filamentous and nanoperiphytic species occurred. The highest values of functional diversity were associated with the algal biomass peak during the colonization and the high water hydrological period, possibly indicating greater efficiency in the ecosystem functioning. These findings show the importance of the functional traits approach in periphyton studies and that the selection of functional traits must be performed taking into account traits that represent the species niche.

ResumoDevido à ausência de conhecimento sobre os padrões para a diversidade funcional de algas perifíticas durante processo sucessional de curto tempo, o presente estudo objetivou avaliar a dinâmica das características funcionais e da diversidade funcional dessas espécies durante a sucessão em um lago de planície de inundação. As características funcionais analisadas foram classe de tamanho, forma de vida, intensidade de aderência ao substrato e estratégias funcionais. Foi avaliada a dinâmica destas características funcionais, considerando riqueza, densidade e biovolume, durante 18 dias de colonização, em dois períodos hidrológicos distintos. A diversidade funcional estimada pelo índice de distância média entre pares (MPD). As características funcionais dominantes se alteraram durante a colonização proporcionado pelo pulso de inundação. Sobre este efeito houve grande desenvolvimento de espécies C-S estrategistas, frouxamente aderidas, filamentosas e nanoperifíticas. Os maiores valores de diversidade funcional foram relacionados com o pico de biomassa algal ao longo da colonização e com o período de águas altas, e que isso provavelmente indica maior eficiência no funcionamento do ecossistema. Este estudo mostrou a importância de incluir as características funcionais nos estudos de algas perifíticas, e que a seleção de características deve ser feita levando em consideração o nicho das espécies.

Myeloproliferative neoplasms:ten years after the discovery of JAK2 V617F gene mutation / 白血病·淋巴瘤

This article focuses on the rapidly evolving understanding of the molecular pathogenetic mechanisms of the bcr-abl-negative myeloproliferative neoplasms (MPN) [myeloproliferative disorders (MPD)],such as polycythemia vera (PV),essential thrombocythemia (ET),and primary myelofibrosis (MF).The amplify therapies were reviewed and IFN-α is an effective agent for these MPN (MPD).Also,the article emphasize once again avoidance MPN and select MPD for such chinese patients.

Epicotyl morphophysiological dormancy in seeds of Lilium polyphyllum (Liliaceae).

Dormancy-breaking and seed germination studies in genus Lilium reveal that the majority of Lilium spp. studied have an underdeveloped embryo at maturity, which grows inside the seed before the radicle emerges. Additionally, the embryo, radicle or cotyledon has a physiological component of dormancy; thus, Lilium seeds have morphophysiological dormancy (MPD). A previous study suggested that seeds of Lilium polyphyllum have MPD but the study did not investigate the development of the embryo, which is one of the main criteria to determine MPD in seeds. To test this hypothesis, we investigated embryo growth and emergence of radicles and epicotyls in seeds over a range of temperatures. At maturity, seeds had underdeveloped embryos which developed fully at warm temperature within 6 weeks. Immediately after embryo growth, radicles also emerged at warm temperatures. However, epicotyls failed to emerge soon after radicle emergence. Epicotyls emerged from >90% seeds with an emerged radicle only after they were subjected to 2 weeks of cold moist stratification. The overall temperature requirements for dormancy-breaking and seed germination indicate a non-deep simple epicotyl MPD in L. polyphyllum.

Expression of mouse PD-1/PD-L1 recombinant protein in prokaryotic cells / 第二军医大学学报

Objective: To establish a molecule binding model of mouse PD-1/PD-L1 protein in vitro, so as to lay a foundation for studying the biological activities of the recombinant protein and to establish a high throughput drug screening model. Methods: Prokaryotic expression plasmid pET28 a (+) /mPDL-1 and pGEX-4T-1/mPD-1 were transformed to E. coli BL21 (DE3), which was then induced with IPTG. The expression products were purified by fast affinity chromatography with FPLC Protein Purification Instrument or gel separation. ELISA and GST pull-down were used to detect the interaction between mPD-1 and mPD-L1. In addition, Alamar blue was used to test the role of protein mixtures in the mixed lymphocyte proliferation. Results: SDS-PAGE and Western blotting analysis showed that the recombinant proteins were successfully expressed. Then purified mPD-1 and mPD-L1 protein was obtained by affinity chromatography, Gel seperation and refolding, etc. ELISA and GST pull-down showed that mPD-1 and mPD-L1 protein had a specific binding activity in vitro. The mPD-1/ mPD-L1 protein had a significantly decreased influence on the proliferation of lymphocytes(P<0. 05). Conclusion: Mouse PD-1/PD-L1 recombinant protein model has been successfully established using purified mPD-1 and mPD-L1 protein expressed prokaryotically, which lays a foundation for high-throughput drug screening.

Experience of YANG Wen-hua in treating myeloproliferative disorders / 中华中医药杂志

Professor YANG Wen-hua has gradually formed her unique academic view and style on myeloproliferative disorders(MPD) during the past 30 years.She summed up and applied the diagnosis and treatment system of'liver heat and blood stasis,purging liver and eliminating stasis,flexibly in clinic.Method of integration of traditional Chinese and western medicine was adopted and got satisfactory effects,which can delay the disease process and transformation,improve the clinical symptoms,complications and quality of life,and prolong survival time.

Psychological Characteristics of the Patients with Low Back Pain by Traffic and Industrial Accidents

OBJECTIVE: To survey characteristic patterns and speculate psychologic factors of the patients with low back pain associated with industrial injury or traffic accidents. METHOD: Nineteen low back pain patients after traffic (12 cases) or industrial (7 cases) accidents were compensation insurance status. 40 controls were low back pain patients without compensation insurance status. All had been evaluated with an electrodiagnostic study. Pain drawings and symptom check list for minor psychiatric disorder (SCL-MPD) were assessed to speculate the characteristics of the psychologic factors. RESULTS: In the electrodiagnostic study patients with compensation insurance status had segmental radiculopathy in5 cases (26.3%) and controls in 18 cases (45.5%). Pain drawings classified as Ransford scores were abnormal in 14 cases (73.7%) of the patients and in 9 cases (24.3%) of the controls. Visual inspection of the pain drawings classified as non-indicative were 12 cases (63.2%) of the patients and 13 cases (31.3%) of the controls. SCL-MPD showed higher somatization, depression and phobic-anxiety scores than the controls. CONCLUSION: Pain drawing and SCL-MPD are available for screening of the psychological factors and management for low back pain of compensation insurance stauts.

Therapeutic Effects of PUVA Therapy with Percentage Increments for Psoriasis, Evaluated by the Changes of Mpd Values / 대한피부과학회지

BACKGROUND: The PUVA therapy of psoriasis is a very effective therapeutic modality that combines the action of light and drugs. Generally the conventional PUVA therapy based on patient's skin type is used in Korea. But there are many reported that conventional PUVA therapy is not suitable in several instances including the determination of oral 8-methoxypsoralen(8-MOP) dose, initial and incremental UVA dose and so on. OBJECTIVE: The purpose of this study is to establish a new protocol of PUVA therapy that is photomedically acceptable. METHOD: From 1997 to 2001, twenty psoriasis patients of moderate to severe grade who visited our clinic, were treated with PUVA therapy. Initial UVA dose was the same as MPD of each patient and proportion of weekly incremental UVA dose was 20% added to previous dose. All patients received PUVA therapy twice a week. The 8-MOP dose was determined by body surface area. RESULT: Total of 8 patients were skin type III, and 12 patients were skin type IV. The average of initial MPD in skin type III was 1.75J/cm2(0.5~2.5J/cm2) and skin type IV was 3.25J/cm2(2.5~4.5J/cm2). The average number of treatments to the end of therapy were 13.63(10~16) in skin type III, and 12.5(8~18) in skin type IV. The total cumulative UVA dose was 44.73J/cm2(30~68.2J/cm2) in skin type III, and 67.98J/cm2(31.6~109J/cm2) in skin type IV. CONCLUSION: The excellent effectiveness and safety of our new PUVA protocol have been demonstrated. We conclude that this PUVA protocol is a very effective, safe, and efficient method for the treatment of psoriatic patients.

Myelodysplastic syndrome transformed to atypical chronic myeloid leukemia——Three cases report and review of literature / 中国癌症杂志

Purpose:To report three cases of myelodysplastic syndrome(MDS) transformed to atypical chronic myeloid leukemia(aCML).Methods:Compared the clinical findings,hemograms and bone marrow features in two different courses of the disease,discussed with review of related literatures.Results:The three patients were all old age.They onset with chronic anemia,the results of BM smear were MDS-RAS and MDS-RAEB;Then leukocytosis occurred in 6-65 months.The aCML were diagnosed according to the BM smear and normal chromosome.Conclusions:The MDS/MPD is a new category of the WHO classification that have both dysplastic and proliferative features.Atypical CML lacks the Ph chromosome and BCR/ABL fusion gene that are the hallmarks of classic CML.This kind of case is seldom seen.

Hypocholesterolemia and neurotic symptoms

BACKGROUND: An association between low serum cholesterol concentrations and depressive symtoms has ever been found in several studies. The objective of this study is to evaluate neurotic symptoms in hypocholesterolemia. METHODS: In the course of two months (from June to August, 1998), 81 subjects were selected among the people who screened in adult disease survey of one university hospital. As the control group, 80 subjects were selected from a healthy population. In the study population, we excluded people who had medical history of hypertension, diabetes mellitus, ischemic heart disease, chronic liver disease and history of any medication to lipid metabolism and other psychotic disease history. Neurotic symptoms were measured by Symptom Checklist for Minor Psychiatric Disorders (SCL-MPD) questionnaire. RESULTS: There was no difference between the distribution of age and sex in the hypocholesterolemia groups. As the level of the education and kind of employment, no significant difference between two groups. Hypocholesterolemia groups scored significantly higher than conrol group in some questionnaire of SCL-MPD. The results of depression scale (p<0.01) and anxiety, hypochondriasis scale (p<0.05) were significant. The men of hypocholesterolemia groups have significant relation to hypochondriasis scale (p<0.001) and the women to anxiety scale (p<0.05). CONCLUSION: Though in some scale of neurotic symptoms, the association between hypocholesterolemia and neurotic symptoms was found in our study. There need to be a further study on the correlation of hypocholesterolemia and neurotic symptoms.

The relation between psychosocial factor of inorganic chest pain and neurotic symptoms

BACKGROUND: Compared to Europe and America neurotic chest pain patients seems to be much more prevalent in Korea. This study was designed to depict various neurotic symptoms of patients with inorganic chest pain. METHOD: In the course of one year(from March, 1997 to March, 1998), 70 subjects were selected among the people who visited the outpatient clinic of department of family medicine with symptom of chest pain. The control group was selected from a healthy population which matched nearly the same number as the chest pain group. Patients were tested by EKG, treadmill, chest X-ray, 2D-UCG and requested to answer SCL-MPD questionnaire. Statistical analysis by means of SPCC/PC+ and for significance using non-parametric Mann-Whitney U test was done. RESULTS: The chest pain group scored significantly higher than the control group in obsessive and compulsive, anger-hostility, depression, anxiety, and somatization scale. male chest pain group scored higher in somatization, anxiety, obsessive-compulsive, hypochondriasis, and depression scale. The female chest pain group scored higher in depression scale. CONCLUSION: Many inorganic chest pain patients complain through various neurotic symptoms. When approaching chest pain patients we should consider the possibility of a psychosocial cause.

Characteristics of the patients of chronic disease

BACKGROUND: It is very important for family physicians to practice with comprehensive approach to patients with chronic illness. A study was done to assess psychosocial aspects of patients with chronic illness and disability and to help physicians manage patients effectively. METHODS: SCL-MPD questionnaires were done in 93 patients with chronic illness and disability who were admitted between April and May in 1997. The results were statistically analyzed by chisquare test and Mann-Whitney U test. RESULTS: 1. The mean score of SCL-MPD were 17.5 for `depression' and 13.78 for `somatization' with statistical significance(P<0.005). 2. Comparison of dimensions of patients with back pain syndrome had higher scoresn for `depression (25.2)', `somatization (22.1)', `hypochondriasis (14.7)', `phobic anxiety (11.6)', `neurasthenic (8.1)' and `interpersonal sensitivity(8.0)' than other disease groups with statistical significance (P<0.05). 3. In comparison of dimensions between males and females, the female group gradually had higher scores than males and, especially, 'somatization' dimension was significantly higher in score (P<0.05). 4. Symptoms ranked top in male and female patients were `54-over coscern about your health' in males and `16-over concern with the fear of having a serious illness' in females. CONCLUSION: Family physicians have to consider not only physical impairment but also psychological aspect of patients with chronic illness for comprehensive management in medical practice.

Psychogenic symptoms in patients with noncardiac chest pain

BACKGROUND: Patients with chest pain are common among outpatients. Several researches shows that chest pain patients can suffer from psychiatric illnesses such as hypochondriasis, depression, anxiety, somatization, panic disorder and so on. This study aims to examine the pschogenic symptoms in patients with noncardiac chest pain METHODS: In this study, the 98 people who have undergone treadmill test for chest pain during the three months from June 1st to September 30 of 1998 were selected, and the 98 patients were asked to respond to the prepared questionnaire and SCL-MPD(symptom check list-minor psychiatric disorders) before they underwent treadmill test. And then, they were classified into two groups. One group consisted of patients with noncardiac chest,pain, and the other group of patients with cardiac chest pain. These two groups were compared in 10 measures, and the compared results were analyzed by t-test. RESULTS: Among the 25 patients with cardiac chest pain, 15 patients were males and 10 patients (38%) were females, and among the 44 patients with noncardiac chest pain, 31 patients (70%) were males, 13 patients (30%) were females. The average age was 47 years old. The average age in patients with noncardiac chest pain was 48, and the 46 for those patients with cardiac chest pain . In the statistical analysis between the patients with cardiac chest pain and those with noncardiac chest pain, significant difference(p<0.005) was shown in the measures such as somatization, depression, phobic anxiety, obsessive-compulsive, neurasthenic, hypochondriacal, anxiety, anger-hostility, interpersonal sensitivity. CONCLUSIONS: As in the analysis the patients with noncardiac chest pain showed significant difference in the symptom check list-minor psychiatric disorder compared to those with cardiac chest pain. We conclude that primary care physician should take more interest in evaluating psychiatric symptoms in patients with noncardiac chest pain.

Neurotic characteristics in headache patients

BACKGROUND: Headache is one of the most common medical complaints. The majority of headaches are not associated with significant organic disease. Many persons are susceptible to headaches at times of emotional or physical distresses. The purpose of this study is to evaluate neurotic symptoms of headache patients. METHODS: The present study was made in the patients with headache symptoms. who had visits t,he outpatient clinic of Family Medicine of a University Hospital from April 1st to July 31st, 1996, 110 subjects with headaches and 136 controls which were closely matched according to sex, age and socioeconomic status. Neurotic symptoms were assessed using the Symptom Check List for Minor Psychiatric Disorders(SCL-MPD). The statistical analysis was made between the two groups. RESULTS: 1) All but 3 items were significantly higher in headache group(p<0.05 : 2 items;p<0.01 : 9 items ; p<0.001 : 53 items). 2) The headache group had a statistically significant higher score of the each neurotic dimension in comparison of the non-headache group (somatization, anxiety, depression , anger-hostility, interpersonal -sensitivity, phobic anxiety, obsessive -compulsive , neurasthenia, hypochondriasis and general) (p<0.001). 3) The age and the presence of occupation were significantly associated with headache symptoms. The somatization and depression scales had the strongest independent association with headaches as compared with other dimensions. CONCLUSIONS: Persons with headache had higher levels of neurotic symptoms and psychological distresses compared to the non-headache group. Physicians need to be aware of the various types of distresses comprehensively with psychosocial assessments and evaluations.

Minor psychiatric disorder Associated with Smoking in Men

BACKGROUND: Smoking is a very dangerous behavior and people know that it will lead to fatal health problems. But, many people continue to smoke. We studied psychiatric aspect of smoking. METHODS: We distributed self-questionnaire to people who visited Dong-San Medical Hospital for periodical examination and checkups between the months of April and June, 1996. It consisted of inquiries on their smoking status and symptom check list for minor psychiatric disorders(SCL-MPD). Among the total of 147 men 58 were current smokers, 63 non-smokers, 26 ex-smokers. We compared minor psychiatric differences between each groups by Student t-test. RESULTS: The mean age of current smokers, ex-smokers and non-smokers were 44.9 +/-8.9, 44.8+/-8.4 and 46.6+/-9.6, respectively. Among 10 dimensions of SCL-MPD, the smokers (includes current smokers and ex-smokers) had significantly higher scores on anger-hostility, interpersonal sensitivity and obsessive-compulsive dimensions than those of non-smokers(p<0.05). When comparing with current smokers and non-smokers, current smokers had significantly higher scores on anger-hostility and obsessive-compulsive dimensions(p<0.05). Between ex-smokers and non-smokers, ex-smokers had significantly higher scores on anger-hostility and obsessive-compulsive dimensions(.p<0.05). But, no significant differences were observed between current smokers and ex-smokers. CONCLUSIONS: Smokers(current smokers and ex-smokers) were highly associated with anger-hostility, interpersonal sensitivity and obsessive-compulsive disorders compared to non-smokers. But, no minor psychiatric differences were observed between current smokers and ex-smokers.

A Study of Psychogenic Symptoms in Chronic Low Back Pain Patients

BACKGROUND: Chronic low back pain(CLBP) is one of the most common afflictions of humans. Between 70% and 80% of the population experience back pain some time during their lives. Especially, back pain is the most common cause of limited activity in individual under age 45. METHODS: The prepared questionnaire and SCL-MPD(symptom check list-minor psychiatric disorders) were presented to subjects who visited our hospital for occupational routine check. The questionnaire was composed of duration and severity of back pain. The subject were divided into two groups, respectively with chronic low back pain history and without history. The differences of psychogenic symptoms between both groups were analysed. RESULTS: In general characteristics, there was no significant difference between both groups. There were significant differences in somatization, anxiety, depression, anger-hostilily, phobic anxiety, neurasthenic, hypochondriacal, interpersonal sensitivity and general dimensions between both groups(P<0.05). There was no significant difference in obsessive-compulsive dimension between both groups. CONCLUSIONS: These results showed the presence of various psychogenic symptoms in chronic low back pain patients. Such psychosocial variables will need to receive additional careful attention in primary care setting.

A Study on the Minimal Phototoxic Dose (MPD) / 대한피부과학회지

In order to measure the MPD with 8-methoxypsoralen, we selected 49 Korean healthy male vlunteers without phototoxic or photosensitive dermatoses. They were divided to 3 groups (Immediate; group 1, 1 hour; group 2, 2 hours', group 3) according to the waiting time, intervals of application of photosensitizer a,nd UVA:irradiation. The reaults were summarized as follows: 1. MPDs of group 1 had no clinical significance. 2, MPDs of group 2 were more than those of group '3 independently of application methods of photosensitizer. 3. In the cases of topical application of 8-MOP, MPDs of group 3 according to reading interval (24 hours, 48 hours and 72 hours after UVA irradiation) were 3.4+/-2.9 J/cm2, 1.9+/-l.5 J/cm' and l. 7+1, 2/cm, respectively. 4 In the cases of oral administration of 8-MOP, MPDs of group 3 according to reading; interval as topical application of 8-MOP were 7.1+/-2.3 J/cm, 4.4+/-1.1 J/ cm2 and 4.2+/-l.2 J/cm2, respectively. 5 MPL)s accarding to the skin types as follows; (waiting time; 2 hours, read- ing interval; 48 hours) a. In the case of topical application of 8-MOP, MPDs of the skin type ]II, 1V and V were 0.9+/-0.5 J/cm2, 1.8+/-1.1 J/cm2 and 3.0+/-l.3 J/cm2 respectively. b. In the case of oral administration of 8-MOP, MPDs of skin type g, W and were 3.5+/-1.1 J/cm2, 4.7+/-1.3 J/cm2 and 6.9+/-l.8 J/cm2, respectively.

The Influence of UVA Radiation on UVB - Induced Erythema / 대한피부과학회지

This study was undertaken to observe the effect of the preirradiation of UVA on the eryt,hematous reaction by UVB. Twenty-five healthy Korean adult male volunteers were taken as subjects. The results were as follows: 1)Preirradiation of 10J/cm and 20j/cm of UVA had no influence on the erythematous reaction induced by UVB. Preirradiation of 30 J/cm of UVA decreased the minimal erythemal dose(MED) of UVB significantly (p<0,05), and 4pJ/cm of UVA dicl very significantly(p<0. 001). 2) Preirradiation dose of UVA(x) and MED of UVB(y) had statistically significant relationship (y=33. 23 - 33 x, r= -0.39, p<0. 05). So preirradiation of UVA decreased MED of UVR in relation with the preirradiation dose. 3) For the objective criteria of skin erythematous reaction induced by the UV irradiation, MED was considered more accurate and efficient than minimal perceptible dose (MPI).