AIM: To explore the correlativity of the oil/water partition of hydroxycamptothecin and its absorp-tion coefficiency in small intestine in rats.METHODS: pH value of water phase in buffer solution in turn took 2.2,4.6,7.4,9.6 and 11,while octanol was adopted as oil phase.After phase equilibrium,HPLC was used to determine the concentration of hydro-xycamptothecin,and oil/water partition coefficient was calculated with the phenol red as volume calibration agent,small intestinal absorption coefficients of rats in different pH were plotted against its oil/water partition coefficients.RESULTS: Oil/water partition coefficient(x) of hydroxycamptothecin and small intestinal absorption(y) altered with the change of pH value of the dispension medium.The linear re-gress equation was constructed as y = 0.001 3x + 0.009 1 with its correlation coefficient R2 being 0.959 7.CONCLUSION: There exists a good linear dependence between oil/water partition coefficient of hydroxycamptoth-ecin and its absorption coefficient in small intestines of rats.Oil/water partition coefficient can be used to design the new oral preparations.

Objective To study the association between house dust endotoxin levels and the airway responsiveness as well as allergen sensitization in adolescence in the urban and rural areas of Guangdong province.Methods Middle school students,aged 13-14,188 (male 109,female 79) from Guangzhou,129(male 70,female 59) from Conghua with positive responses,and 231 (male 125,female 106) and 307(male 145,female 162) of their respective reference students are selected from questionnaire prescreening.A detailed questionnaire,the lung function test,histamine bronchial provocation test,skin prick test and peripheral blood eosinophil count are undertaken.Seventy-six students from Guangzhou and 80 from Conghua were selected randomly for mattress dust sample collection to detect the levels of endotoxin.Results The prevalence of wheeze symptom,diagnosed asthma,nasal symptoms and allergic rhinitis of Guangzhou was significantly higher than that of Conghua (P＜0.0001),with 28.6％,27.7％,66.0％,46.4％ for Guangzhou respectively,and 5.0％,2.5％,31.0％,6.2％ for Conghua respectively.The positive rates of bronchial provocation test and skin sensitization against Dermatophagoides pteronyssinus(Der.p),D.farinae (Der.f),cat and dog allergen in the students of Guangzhou were significantly higher than that of Conghua (P＜0.0001).The positive rate of cockroach of Conghua was significantly higher than that of Guangzhou (P＜0.0001).The levels of endotoxin (amount,concentration and load) of samples from Conghua were significantly higher than that from Guangzhou (Conghua:6452 EU,10.95 EU/mg,1794 EU/m2 ;Guangzhou:1591 EU,6.45 EU/mg,508.80 EU/m2,respectively).PD20-FEV1 was correlated positively with endotoxin amount(r=0.174,P＜0.05).The diameters of the skin wheal size for Der.p and Der.f were correlated inversely with endotoxin amount and load (P＜0.001).Conclusion The prevalence of wheeze symptom,diagnosed asthma,nasal symptoms and allergic rhinitis in 13-14 year-old adolescent of Guangzhou was significantly higher than that of Conghua.Cockroach was the second major allergen of Conghua followed by house dust mite.The level of endotoxin was correlated positively with PD20-FEV1,but correlated inversely with skin sensitization to Def.p and Der.f.The study suggests that environmental endotoxin may have effect to protect children from developing allergic diseases.

This paper explore the possibility of using the partition of 10-hydroxycamptothecin in the phases of liposome and water to predict the absorption of the drug in small intestine of rats. In order to certify this theory, the in vivo absorption model have been used to study the absorption of 10-hydroxycamptothecin in the small intestine of rats while altering the pH of the medium. The correlation has been explored between the partition of drug in the phases of liposome and water and the absorption of drug in the small intestines of rats. And it was found that the partition of 10-hydroxycamptothecin in the phases of liposome and water and the absorption of the drug in small intestines of rats altered with the changes of pH, and there existed a good relative coefficient between them. All of these indicated that partition of 10-hydroxycamptothecin in phases of liposome and water can be used to predict its absorption in small intestines of rats.
Animals ; Camptothecin ; analogs & derivatives ; chemistry ; pharmacokinetics ; Chromatography, High Pressure Liquid ; Hydrogen-Ion Concentration ; Intestinal Absorption ; physiology ; Intestine, Small ; metabolism ; Liposomes ; chemistry ; Rats ; Water ; chemistry

Objective To retrieve,evaluate and integrate evidence related to prevention and management of lifestyle-related dry eye patients.Methods The clinical decisions,recommended practices,evidence summaries,technical reports,guidelines,expert consensuses and systematic evaluations on the prevention and management of lifestyle-related dry eye patients in domestic and foreign databases were retrieved by the computer.The evidence was extracted and summarized according to the subject after the independent literature quality evaluation by 2 researchers.The literature retrieval time limit was from the establishment of the databases to September 2022.Results According to the inclusion criteria,13 pieces of the literature were screened,including 1 guideline,5 systematic reviews,3 expert consensuses,2 technical reports and 2 evidence summaries.Through literature reading,evidence extraction and classification,a total of 25 pieces of evidence were summarized,including assessment,symptom identification,identification of risk factors,artificial tear management,eye care,diet management,health guidance,follow-up education.Conclusion This study summarized the best evidence of prevention and management of lifestyle-related dry eye patients,so as to provide references for nurses to carry out clinical practice.In the process of evidence transformation,the actual situation should be combined to improve the quality of nursing.