Objective To establish a novel convenient loop?mediated isothermal amplification(LAMP)method with the unique genes coding Plasmodium helical interspersed sub?telomeric superfamily(PHIST)for the rapid molecular diagnosis of P. falciparum. Methods The unique genes coding PHIST with high expression mRNA profile during the ring form or schizont period of P. falciparum were screened and selected from the PlasmoDB database. The LAMP primers of targeted genes were de?signed by the online software(PrimerExplorer V4). The LAMP assay was executed by the color?displaying method with SYBR Green. The dried blood spots of P. falciparum from clinical isolates were collected and the genomic DNA(gDNA)was extracted. For evaluation of sensitivity,the gDNA was diluted to four gradients(10?1,10?2,10?3,and 10?4). For assessment of specificity, the gDNA(s)of P. vivax,P. yoelii,Taenia saginata,and Schistosoma japonicum were also extracted. Results Totally,61 P. falciparum unique genes coding PHIST were found. The PF3D7_1372300 with high expression value during the ring form and PF3D7_1401600 with high expression value during the schizont period were selected for LAMP assay. The lowest detectable lim?its of PF3D7_1372300 and PF3D7_1401600 were 130.5 parasite/μl and 1 305.3 parasite/μl,respectively. Specific tests showed the amplified products of P. falciparum was positive and all the others including P. vivax,P. yoelii,T. saginata,and S. japoni?cum were negative. Conclusions The established LAMP method with PF3D7_1372300 gene is sensitive,specific,simple and useful. It can be applied to the field investigation and clinical diagnosis for falciparum malaria.

Objective To investigate the relationship between nutritional risk status and implementation of nutrition therapy in mechanical ventilated (MV) chronic obstructive pulmonary disease (COPD) patients, so as to provide evidence for individualized nutrition therapy. Methods A prospective multicenter observational study was conducted. MV COPD patients admitted to Department of Intensive Care Units (ICU) of 10 County Hospitals in Zhejiang Province from January 2015 to January 2016 were enrolled, and according to nutrition risk screening 2002 (NRS2002) score, they were divided into nutritional high risk group (NRS2002 3-5) and nutritional extremely high risk group (NRS2002 6-7). Nutrition therapy situation and hospital mortality were compared between the two groups; multivariate Cox regression analysis was used to analyze the risk factors affecting the prognosis of patients with COPD under mechanical ventilation. Kaplan-Meier curve was used to analyze the prognosis at 30 days; receiver operating characteristic (ROC) curve was used to test the robustness of multivariable regression analysis. Results ① One hundred and six COPD patients with MV were analyzed; among them, 90 patients were in the nutritional high risk group, and 16 were in the nutritional extremely high risk group. There were no significant differences in age, gender and body mass index (BMI) between the two groups (all P > 0.05); the acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score, NRS2002 score in patients of nutrition risk extremely high group were obviously higher than that in patients with nutrition high risk group (APACHEⅡ: 24.9±6.1 vs. 20.3±5.8, NRS2002 score: 6.3±0.5 vs. 4.2±0.8, both P < 0.05). ② Patients in both groups received early enteral nutrition (EN) therapy, the proportion of patients in nutritional extremely high risk group received early EN was lower than that of patients in the nutritional high risk group [12.5% (2/16) vs. 17.7% (16/90)], along with the prolongation of hospital stay, the proportions of patients beginning to receive the EN were gradually increased in the nutrition extremely high risk group and high risk group, after 2 days the EN increased significantly, and reached the highest value on day 6 after entering ICU [100.0% (16/16), 98.9% (89/90), respectively]; within 3 days after admission into ICU, the proportion of EN in nutrition extremely high risk group was obviously lower than that in nutrition high risk group, and from day 4, there was no statistical significant difference in proportion of EN between the two groups (all P > 0.05). The time to start parenteral nutrition (PN) treatment was relatively early admission to the ICU on day 1 and the proportion of this therapy was high in the two groups [56.2% (9/16), 27.7% (25/90), respectively], the PN proportion did not decrease with the length of hospitalization and the increase of EN. The proportion of patients in the nutrition extremely high risk group who started PN treatment was higher, which reached 56.2% admission to the ICU on day 1.③ With extension of hospital stay, the calories of EN were gradually increased in the nutritional high risk group, the highest calories in nutritional high risk groups was 4 318 (3 912, 4 812) kJ/d at day 7; while the highest calories in nutritional extremely high risk groups was 3 602 (2 167, 4 615) kJ/d at day 6 and a slight decreased at day 7; the difference of calories within the first week between the two groups had no significance (all P > 0.05). The calorific value of PN therapy remained at a constant level during hospitalization within 7 days, and after admission into ICU for 4-5 days, the target range of calories was achieved. ④ Kaplan-Meier survival curve analysis showed that the mortality at 30 days in the extremely high risk group was significantly higher than that in the high risk group [62.5% (10/16) vs. 11.1% (10/90), χ2 = 15.4, P < 0.01]. ⑤ Multiple cox-regression analysis showed that NRS2002 scoring was the independent risk factor affecting the mortality of patients in hospital [odds ratio (OR) = 2.08, 95% confidence interval (95%CI) = 1.39-3.12, P = 0.005]. ⑥ ROC curve analysis: according to ROC curve analysis of the effectiveness of multi-factor regression model, area under ROC curve (AUC) was 0.79, sensitivity was 70.00%, specificity was 74.42%, positive likelihood ratio was 2.74, negative likelihood ratio was 0.40, 95% confidence interval (95%CI) was 0.702-0.864, P = 0.001, and it showed that the regression model had a good prediction effect. Conclusions MV COPD patients have significant nutritional risk and all receive early EN therapy. The proportion of beginning to use PN treatment in patients with nutritional extremely high risk is relatively high. Initial nutritional status is the independent risk factor of poor prognosis in MV patients with COPD.