多环芳烃水平与人类直肠癌、肝癌发生的相关性研究(英文)

Objective: The aim of this study was to investigate the effect of polycyclic aromatic hydrocarbons (PAHs) in rectal carcinoma and hepatocarcinoma genesis. Methods: The PAHs in the human rectal cancer and liver cancer tissues, the adjacent tissues and homologous tissues without rectal cancer or liver cancer were extracted by ultrasonic wave. The extracts were then cleaned up and enriched by solid phase extraction, analyzed by high performance liquid chromatography (HPLC) with fluorescence spectroscopy. Results: Four kinds of PAHs were detected in human rectal and hepatic tissues. The contents of pyrene, 2-methylanthracene and benzo (a) pyrene in both rectal cancer tissues and adjacent homologous tissues were higher than rectal tissues without rectal cancer, the differences were statistically significant (P < 0.05). The contents of phenanthrene in the three kind of tissue were not significant (P > 0.05). The differences of the content of each PAHs between rectal cancer and adjacent tissue were not significant (P > 0.05). The contents of the four PAHs in the three kinds of liver tissues were not statistically significant (P > 0.05). Conclusion: PAHs are found in human rectal tissues or hepatic tissues. The contents of PAHs in human rectal tissue may have an effect on the occurrence of human rectal cancer while the contents of PAHs in human hepatic tissues may have not ones.

Nursing Experience of Early Application of Nasoenteric Tube for Enteral Nutrition in Critically Ill ICU Patients

Objective:To investigate the effective nursing measures of early application of nasoenteric tube for enteral nutrition in critically ill patients in ICU,and to summarize the nursing experience.Methods:The study was carried out in June 2023–November 2023.62 samples of ICU critically ill patients were selected,all of whom used enteral nutrition by mesenteric tube and were grouped into an observation group(n=31)and a control group(n=31)by using the numerical table randomization method.The patients in the control group were basic nursing interventions,and the patients in the observation group were comprehensive quality care,comparing the nutritional indexes,complication rates,and nursing satisfaction between the two groups.Results:All nutritional indicators of the observation group were higher than those of the control group after nursing intervention(P<0.05);the complication rate of the observation group was lower than that of the control group(P<0.05);the nursing satisfaction of the observation group was higher than that of the control group(P<0.05).Conclusion:Comprehensive quality nursing care during the early application of a gastroenteric tube for enteral nutrition in critically ill patients in the ICU can improve nutritional indexes,reduce the incidence of complications and improve nursing satisfaction.

Activity after Site-Directed Mutagenesis of CD59 on Complement-Mediated Cytolysis

CD59 may inhibit the cytolytic activity of complement by binding to C8/C9 and protect host cell membranes against homologous membrane attack complex （MAC）. However, CD59 is widely overexpressed on tumor cells, which has been implicated in tumorigenesis. The active site of CD59 relative to MAC is still confused. As reported the MAC binding site is located in the vicinity of a hydrophobic groove on the membrane distal face of the protein centered around residue W40. Here two site-directed mutagenesis were performed by overlapping extension PCR to delete residue W40 site （Mutant 1, M1） or to change C39W40K41 to W39W40W41 （Mutant 2, M2）. Then we constructed mutant CD59 eukaryotic expression system and investigated their biological function on CI-IO cells compared with wild-type CD59. Stable populations of CHO cells expressing recombinant proteins were screened by immunotechnique. After 30 passages culturing, proteins could be tested. Dye release assays suggest that M1CD59 loses the activity against complement, while M2CD59 increases the anti-complement activity slightly. Results indicate that W40 of human CD59 is important to its activity, and prohibition of this site may be a potential way to increase complement activity and to treat tumors. Cellular ＆ Molecular Immunology.

Analysis of the chemoprophylactic effect on close contacts of patients with active tuberculosis and positive tuberculin skin tests

Objective:The current study analyzed the chemoprophylactic effect of isoniazide on close contacts of patients with active tuberculosis and positive tuberculin skin tests(TSTs).Methods:A total of 1206 close contacts of patients with active tuberculosis and strongly-pos-itive TSTs were enrolled.The patients had chest X-ray examinations.Patients without tuberculosis and other diseases were divided into the following groups:90 patients in the prophylaxis group,who were given 300 mg of isoniazid qd(3-5 mg/kg for children)over a 10-month treatment course;and 89 patients in the control group without drug therapy.Both groups were followed for 10 years.Results:(1)There were 568 patients with negative results and 638 with positive results,includ-ing 445 with ordinarily-and moderately-positive results,and 193 with strongly-positive results(a positive rate of 52.9%[638/1206]and a strongly-positive rate of 16.0%[193/1206]).Fourteen tuber-culosis patients were identified(tuberculosis detection rate of 1.1%).(2)During the 3-year period of follow-up,there were 4 patients in the prophylaxis group and 12 patients in the control group who acquired tuberculosis(a morbidity rate of 4.7%[4/84]and 13.4%[12/89],respectively),and the dif-ference was statistically significant(χ^(2)=3.916,P=0.048).Six patients in the prophylaxis group,all of whom were children,discontinued medication use during the course of treatment due to adverse drug reactions,for an adverse drug reaction occurrence rate of 6.6%(6/90),a medication completion rate of 93.3%(84/90),and a 3-year protection ratio of 64.6%.(3)During the 4-6 year period,there were two patients in the prophylaxis group and three patients in the control group who acquired tubercu-losis(a morbidity rate of 2.5%[2/78]and 4.1%[3/73],respectively),two in the prophylaxis group and four in the control group who were lost to follow-up(a loss to follow-up rate of 2.5%[2/80]and 5.1%[4/77],respectively),and the difference was not statistically significant(χ^(2)=0.006,P=0.940;χ^(2)=0.215,P=0.643).(4)During the 7-10 year study,there was one patient in the prophylaxis group and two patients in the control group who acquired tuberculosis(a morbidity rate of 1.3%[1/72]and 3.1%[2/64],respectively),and four in the prophylaxis group and six in the control group who were lost to follow-up(a loss to follow-up rate of 5.2%[4/76]and 8.5%[6/70],respectively),and the dif-ference was not statistically different(χ^(2)=0.011,P=0.918;χ^(2)=0.176,P=0.675).(5)Within 10 years,there were 7 patients in the prophylaxis group and 17 patients in the control group who acquired tu-berculosis(a morbidity rate of 8.3%[7/84]and 21.5%[17/79],respectively;χ^(2)=4.770,P=0.029),and 6 in the prophylaxis group and 10 in the control group were lost to follow-up(the loss to follow-up rate was 7.1%[6/84]and 11.2%[10/89],respectively;χ^(2)=0.863,P=0.353).Conclusion:Close contacts of patients with active tuberculosis are at high-risk for acquir-ing tuberculosis.It is safe and effective for patients with strongly-positive TST results to undergo isoniazid chemoprophylaxis for 10 months.