AIM: To investigate the changes in intracellular potassium activity(a iK) and membrane potential(V_m) induced by low external sodium infusion (Low _o) and to detect the mechanisms involved and the relationship between a iK and V_m. METHODS: a iK and V_m were measured in infusion with different sodium concentrations using methods of convenient and ion selective microelectrodes in guinea pig ventricular myocardium. RESULTS: Low _o resulted in a decrease in a iK and an increase in V_m in a Na + concentration-dependent manner.At the same time,contraction and resting potential increased, and action potential duration decreased markedly,but action potential amplitude was not affected. A change of the pH from 7.4 to 7.0 in low _o solution reduced the decrease in a iK, but did not affect the increase in V_m. CONCLUSION: A better linear relationship appeared between the changes in a ik and _o or in V_m and _o,while during each low _o the change in both a iK or V_m may reach a new balance level.

OBJECTIVETo investigate the chemical constituents of the culture of Phellinus igniarius and their phamacological activities.

METHODThe constituents were isolated by using a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, and reversed-phase HPLC. Structures of the isolates were identified by spectroscopic data analysis. Cytotoxic, neuroprotective, hepatoprotective, anti-inflammatory, and anti-HIV activities were screened by using cell-based models.

RESULTTwenty-nine constituents were isolated. Their structures were identified as three sesquiterpenes: 3S,9R,10S-3-hydroxy-11, 12-O-isopropyldrimene(1), 3S, 9R, 10S-3, 11, 12-trihydroxydrimene (2), and 3S, 4S, 9R, 10S-11, 12, 14-trihydroxydrimene(3); three steriods: 24R-ergosta-4, 6, 8(14), 22-tetraen-3-one (4), stigmasta-7, 22-diene-3b, 5a, 6a-triol (5), and 5a, 8a-epi dioxyergosta-6, 22-diene-3b-ol (6); fourteen cyclo-dipeptide: cyclo (L-Pro-L-Val) (7), cycle (L-Leu-D-Pro) (8), cyclo (L-Leu-L-Pro) (9), cyclo (ILe-Pro) (10), cyclo (Gly-Leu) (11), cyclo (Phe-Ser) (12), cyclo (Ala-Pro) (13), cyclo (Ala-Phe) (14), cyclo (4-HyP-Phe) (15) , cyclo (L-Phe-D-Pro) (16), cyclo (D-Phe-D-Pro) (17), cyclo (6-HyP-Phe) (18), cycle (Gln-Pro) (19), and cycle (Asn-Leu) (20); and nine other compounds: N-acetyl-phenylalanine (21), adenosine (22), phenyldiethanol (23), o-hydroxy-phenylethanol (24), benzoic acid (25), p-methoxybenzoic acid (26), m-methoxybenzoic acid (27), hexadecanoic acid (28), and 3-pyridinecarboxylic acid (29). In the in vitro assays, at a concentration of 1 x 10(-5) mol x L(-1), compounds 5 and 8 showed neuroprotective activity against MPP+ induced PC12-syn cell damage, with a relative cell proliferation rate of 90.3% and 87.5% (P < 0.05). At 1 x 10(-5) mol x L(-1), compounds 12 and 18 showed hepatoprotective activities against DL-galactosamine-induced toxicity examined in WB-F344 cell, with cell survival rates of 25% and 24%, respectivily.

CONCLUSIONCompounds 1-29 were obtained from P. igniarius for the first time. Compounds 5 and 8 showed potent PC12-syn protective activities, while 12 and 18 showed hepato cytes (WB-F344 cells) protective activities.

Animals ; Basidiomycota ; chemistry ; growth & development ; Cell Proliferation ; drug effects ; Culture Techniques ; Hepatocytes ; cytology ; drug effects ; Neuroprotective Agents ; analysis ; pharmacology ; Organic Chemicals ; analysis ; pharmacology ; PC12 Cells ; drug effects ; Rats

Objective:To establish autoverification rules for coagulation tests in multicenter cooperative units, in order to reduce workload for manual review of suspected results and shorten turnaround time (TAT) of test reports, while ensure the accuracy of results.Methods:A total of 14 394 blood samples were collected from fourteen hospitals during December 2019 to March 2020. These samples included: Rules Establishment Group 11 230 cases, including 1 182 cases for Delta check rules; Rules Validation Group 3 164 cases, including 487cases for Delta check; Clinical Application Trial Group 77 269 cases. Samples were analyzed for coagulation tests using Sysmex CS series automatic coagulation analyzers, and the clinical information, instrument parameters, test results, clinical diagnosis, medication history of anticoagulant and other relative results such as HCT, TG, TBIL, DBIL were summarized; on the basis of historical data, the 2.5 and 97.5 percentile of all data arranged from low to high were initially accumulated; on the basis of clinical suggestions, critical values and specific drug use as well as relative guidelines, autoverification rules and limits were established.The rules were then input into middleware, in which Stage I/Stage II validation was done. Positive coincidence, negative coincidence, false negative, false positive, autoverification pass rate, passing accuracy (coincidence of autoverification and manual verification) were calculated. Autoverification rules underwent trial application in coagulation results reports.Results:(1) The autoverification algorisms involve 33 rules regarding PT/INR, APTT, FBG, D-dimer, FDP,Delta check, reaction curve and sample abnormalities; (2)Autoverification Establishment Group showed autoverification pass rate was 68.42% (7 684/11 230), the false negative rate was 0%(0/11230), coincidence of autoverification and manual verification was 98.51%(11 063/11 230), in which positive coincidence and negative coincidence were respectively 30.09% (3 379/11 230) and 68.42%(7 684/11 230); Autoverification Validation Group showed autoverification pass rate was 60.37%(1 910/3 164), the false negative rate was 0%(0/11 230), coincidence of autoverification and manual verification was 97.79%(3 094/3 164), in which positive coincidence and negative coincidence were respectively 37.42%(1 184/3 164) and 60.37%(1 910/3 164); (3) Trialed implementation of these autoverification rules on 77 269 coagulation samples showed that the average TAT shortened by 8.5 min-83.1 min.Conclusions:This study established 33 autoverification rules in coagulation tests. Validation showedthese rules could ensure test quality while shortening TAT and lighten manual workload.