Oral Presentation No. 53 Dose-related preprocedural patency of the infarct-related artery after zalunfiban (RUC-4) administration upon arrival at the catheterization laboratory in ST-elevation myocardial infarction: insights from the phase IIa study

Background

The importance of time to reperfusion after ST-elevation myocardial infarction (STEMI) is well established. Pre-hospital use of glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors improves pre-percutaneous coronary intervention (PCI) perfusion rates, but they require intravenous administration and continuous infusions and so are difficult for ambulance services to administer. Zalunfiban (RUC-4) is a novel, subcutaneously administered, GPIIb/IIIa inhibitor specifically developed to facilitate pre-hospital administration, thereby maximizing the chance for early reperfusion. This sub-analysis investigated the incidence of complete reperfusion (TIMI grade 3 flow) before primary PCI in patients treated with zalunfiban on arrival at the catheterization laboratory as a function of the dose of zalunfiban.

Material and methods

This was a prospective, single-centre, open-label, phase IIa study designed to assess the pharmacodynamics, pharmacokinetics, and tolerability of zalunfiban in patients with STEMI undergoing primary PCI. Zalunfiban was administered immediately upon arrival at the catheterization lab, which was ∼10–15 minutes before the initial angiogram used to assess TIMI grade flow.

Results and conclusion

A total of 27 patients received a weight-adjusted subcutaneous injection of zalunfiban in escalating doses (0.075 mg/kg [n = 8], 0.090 mg/kg [n = 9], or 0.110 mg/kg [n = 10]). Of these, 25 patients were evaluable for angiographic analysis. TIMI flow grade 3 pre-PCI was observed in 1/7, 2/9 and 5/9 patients and showed a dose-related effect (Ptrend = 0.04). The ongoing international, phase III, double-blinded, randomized, placebo-controlled, CELEBRATE trial is designed to assess whether a single, ambulance-based pre-hospital injection of zalunfiban results in improved clinical outcome.

Funding

This study was supported by CeleCor Therapeutics.

Oral Presentation No. 006 Postoperative Myocardial Injury due to Platelet Reactivity in Patients undergoing Vascular Surgery

Background

Postoperative myocardial injury (PMI) after major vascular surgery, detected by elevated cardiac troponin (cTn), has been associated with morbidity and mortality. It is unclear whether the pathophysiology of PMI is determined by increased platelet activity.

Objective

To examine the relationship between platelet activation (P-selectin expression) and PMI(cTn release as continuum) in patients undergoing elective open abdominal aortic surgery in the early post-operative period.

Methods

This prospective, single-centre, observational, cohort study included 33 patients undergoing elective open abdominal aortic surgery between March 2018 and April 2021. Patients were routinely treated with aspirin. Unstimulated platelet activation was measured by platelet bound P-selectin expression (range 0–100%). Explorative coagulation measurements were: stimulated platelet aggregation measured with the VerifyNow® assay (aspirin cartridge), with the Multiplate® analyzer (ASPI, ADP and TRAP) and stimulated coagulation status evaluated by the TEG® Haemostasis Analyzer System (global haemostasis cartridge). The primary outcome was cTn release assessed by the fifth generation high-sensitive cTn assay. Multivariable generalized linear mixed models were used to evaluate the association between platelet function and cTn concentrations over time.

Results

Ten patients (29.4%) developed PMI. Increased P-selectin expression directly after surgery was associated with the cTn concentrations over 48 h (β = 1.39(1.1–1.75), P = 0.0064). No association was found between P-selectin measured later (at 24 h or 48 h) after surgery and cTn concentrations. Furthermore, there was no association between the explorative coagulation parameters and cTn release.

Conclusion

Increased P-selectin expression measured directly after surgery is associated with elevated cTn concentrations in the early postoperative period in patients undergoing elective open abdominal aortic surgery.

The Total Thrombus Formation (T-TAS) platelet (PL) assay, a novel test that evaluates whole blood platelet thrombus formation under physiological conditions

Dual antiplatelet therapy (DAPT, aspirin, and a P2Y₁₂ inhibitor) reduces thrombotic events in patients with coronary artery disease (CAD). The T-TAS PL assay uses arterial shear flow over collagen surface, better mimicking in vivo conditions compared to conventional agonist-based platelet function assays, to evaluate platelet function. Here, the platelet function in patients taking DAPT is evaluated with the T-TAS PL assay. In 57 patients with CAD, taking DAPT ≥7 days (n = 22 for clopidogrel, n = 15 for prasugrel, n = 20 for ticagrelor), T-TAS PL assessments were performed in duplicate, and expressed as area under the flow pressure curve within a 10-minute period (AUC10). The duplicate measurements were strongly correlated (r = 0.90, p < .001), with an intra-assay coefficient of variation (CV) of 11,5%. For clopidogrel, the median AUC10 was 11.5 (IQR5.9-41.8), for prasugrel 28.8 (IQR10.3-37.6), and for ticagrelor 8.9 (IQR 6.4-10.9). All measurements were below the AUC10 cutoff of 260 measured in healthy volunteers, suggesting excellent discrimination of DAPT-treated and untreated persons. The new T-TAS PL assay demonstrated complete discrimination of platelet function in patients on DAPT based on an established cutoff. Ticagrelor showed lower levels of platelet function and a more uniform response compared to prasugrel and clopidogrel.

[Research progress on the occurrence and prevention of low back pain in naval officers and soldiers]

Low back pain (LBP) is a common occupational disease among naval officers and soldiers. This article reviewed the incidence of LBP in naval personnel in different positions in recent years, and analyzed the causes combined with the operating environment and occupational characteristics of personnel in different positions in order to clarify the causes of LBP in naval officers and soldiers in different positions and improve their awareness of the disease. Moreover, this study aims to help naval officers and soldiers to take protective measures in training life to reduce the incidence of LBP.

[Analysis on the clinical therapeutic effects of arterial first approach pancreatoduodenectomy in the treatment of borderline resectable pancreatic adenocarcinoma]

Objective: To compare the clinical therapeutic effects of arterial first approach pancreaticoduodenectomy(AFA-PD) with standard approach pancreaticoduodenectomy(SPD) in the treatment of borderline resectable pancreatic cancer (BRPC). Methods: A retrospective analysis of the clinical data of 113 cases of pancreatic cancer patients from January 2014 to August 2015 at Department of Hepato-Biliary-Pancreatic Surgery, Changhai Hospital, the Second Military Medical University, including 43 cases in AFA-PD group and 70 cases in SPD group.Every patient had gone high-resolusion computed tomography before the surgery, when BRPC was definitely diagnosed by both experienced radiologist and pancreatic surgeon.There were 24 males and 19 females in the AFA-PD group, with average age of (61.6±10.2)years.And in the SPD group, there were 47 males and 23 females, with average age of (62.7±9.4)years. Results: The operation time was (210.7±31.5)minutes in AFA-PD group, (187.9±27.4)minutes in SPD group, and peroperative bleeding volume was (1 007.1±566.3)ml in AFA-PD group, (700.0±390.0)ml in the other group.Those two indicators of AFA-PD group, compared with SPD group, were relatively higher, the difference was statistically significant(all P<0.01). And with regard to postoperative diarrhea(9.3% vs.5.7%), postoperative 1, 3 days of white blood cells(postoperative 1 day: (13.3±1.1)×10(9)/L vs.(12.4±2.4)×10(9)/L; postoperative 3 days: (12.7±1.6)×10(9)/L vs.(11.7±2.5)×10(9)/L), postoperative 1, 3, 5 days of peritoneal drainage fluid volume(postoperative 1 day: (184±42)ml vs.(156±54)ml; postoperative 3 days: (155±48)ml vs.(133±35)ml; postoperative 5 days: (66±20)ml vs.(47±31)ml), the differences between the two groups were statistically significant (all P<0.05). One patient in the SPD group was treated with unplanned secondary surgery for postoperative intraperitoneal hemorrhage, and the patient was cured and discharged.There was no death in the two groups within 30 days after surgical operation and no patient with positive gastric margin, duodenal margin, or anterior margin.The resection rate of superiormesenteric artery(SMA) margin R0 in AFA-PD group was higher than that in SPD group (P=0.019). The two groups were followed up for 14 to 30 months.As for AFA-PD group, the average survival time, progression free survival time and median survival time was respectively (20.4±1.2)months, (21.5±1.4)months and 20 months.There were 3 cases(7.0%) with local recurrence and 8 cases(18.6%) with liver metastasis or distant metastasis.In the SPD group, the average survival time, progression free survival time and median survival time was (17.1±1.1)months, (16.4±1.3)months and 16 months, respectively.There were 13 cases(18.6%) with local recurrence and 25 cases(35.7%) with liver metastasis or distant metastasis.As a result, the AFA-PD group had longer survival time(P=0.001)and progression free survival time(P=0.002). However, the lower local recurrence and distant metastasis rate in AFA-PD group did not reach statistical standard (P>0.05). Conclusion: The arterial first approach pancreaticoduodenectomy is safe and effective in the treatment of borderline resectable pancreatic cancer, which can improve the resection rate of SMA margin R0, and prolong patient survival time.

[The microbiology of chronic rhinosinusitis with nasal polyps in different phenotype of peripheral blood eosinophils]

Objective:To investigate the association between immune status and microbial community in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) in different phenotype of peripheral blood eosinophils (PBEOS).Method:Retrospective analysis of clinical data of 125 patients with CRSwNP and and 49 control subjects was performed. According to the proportion of peripheral blood eosinophils, the patients with CRSwNP were divided into PBEOS normal group and PBEOS elevated group. The samples of nasal secretions in middle meatus were collected, and then isolated and identified by microbial culture. Differences of microbial colonization rate between the groups were analyzed. SPSS 19.0 software was used to analyze the data.Result:There were 61 cases in PBEOS normal group (0<PBEOS≤ 5%), 64 cases in PBEOS elevated group (PBEOS> 5%) and 49 control subjects.In patient with CRSwNP, the positive rate of microbial culture was 84.4%, and the main microorganisms were Gram positive Aerobic and facultative anaerobic bacteria. The most common bacteria were coagulase negative staphylococci, Staphylococcus epidermidis (S. epidermidis) and Corynebacterium. The average positive rate of Staphylococcus aureus (S.aureus) was 10.4%, and S. epidermidis was 20.0%. The positive rate of S. aureus in the elevated group was higher than that in the normal group (17.2%, 3.3%), and the rate of S. epidermidis was lower (10.9%, 29.5%). The positive rate of S. epidermidis in the elevated group was also lower than that in control subjects (10.9%, 30.6%).Conclusion:In different PBEOS phenotypes, the colonization rate of S. aureus and S. epidermidis showed the opposite trend. In contrast to the normal goup, the colonization rate of S. aureus in the elevated group increased, and the rate of S. epidermidis decreased. At the same time, the colonization rate of S.epidermidis decreased in elevate group in contrast to the control subjests. This suggests that S. aureus may promote eosinophilic inflammatory response and S. epidermidis may promote noneosinophilic inflammatory response, which plays protective role.

Characteristics of Neoplasm Occurrence and the Therapeutic Effect of Sirolimus in South Chinese Kidney Transplant Recipients

Kidney transplantation (KTx) recipients are at a higher risk of oncogenesis when compared to the general population. Sirolimus (SRL), a potent immunosuppressant, has shown promising antineoplastic effects in vitro and in vivo. This study retrospectively analyzed the neoplasm occurrence and the efficiency of SRL on unresectable malignancies in South Chinese KTx recipients. Thirty-three (1.64%) of 2017 patients who received KTx from January 1984 to December 2004 developed neoplasms at 4 to 117 months posttransplant, mostly in digestive organs (33.3%), the hematologic system (15.2%), or the skin (12.1%). The most common type was liver cancer (24.2%), followed by skin cancer, lymphoma, and thyroid cancer (9.1%). The median survival times were 41.5 and 6.0 months for those who did (n = 10) receive radical surgery or did not (n = 23), respectively. The 20-month survival rates were 70.0% versus 13.0% (P < .01). For unresectable patients, the median survival time of those treated with SRL (n = 8) was 14.5 months compared to 3.0 months for those who did not (n = 15). The survival rates at 12(th) and 20(th) months were 75.0% and 37.5% in the SRL group and 6.7% and 0% in the non-SRL group (P < .05). In conclusion, when compared with Western studies, a lower incidence and unique location pattern (liver cancer-dominant) are characteristics of de novo posttransplant neoplasms in South Chinese KTx recipients. Early diagnosis and feasible radical surgery are favorable for prognosis, and SRL is a treatment of choice for KTx recipients with neoplasms.

Clinical Pharmacokinetics of Tacrolimus After the First Oral Administration in Combination with Mycophenolate Mofetil and Prednisone in Chinese Renal Transplant Recipients

INTRODUCTION

Data on tacrolimus pharmacokinetics in combination with mycophenolate mofetil and prednisone are scarce in Chinese renal transplantation recipients. The purpose of this study was to detect interpatient pharmacokinetic variability of tacrolimus and to assess the predictability of individual tacrolimus concentrations at various times for the area under the curve (AUC) seeking to find the best sampling time for an abbreviated AUC to predict the total body exposure of tacrolimus after the first oral dose in Chinese renal transplantation recipients.

METHODS

Sixteen primary kidney transplant recipients were treated with methylprednisolone and antilymphocyte globulin for 3 days. The first tacrolimus oral dose (0.075 mg/kg) was given at day 3 posttransplant. Mycophenolate mofetil and prednisone were administered orally posttransplant. Blood samples were obtained at 0.5, 1.0, 1.5, 2.0, 3.0, 5.0, 8.0, and 12.0 hours after taking the first oral dose. Tacrolimus blood concentrations were measured by ELISA. Twelve-hour AUC (AUC12) for each patient was calculated using the linear trapezoid rule. Associations between the blood concentration at each sampling time point and the AUC12 were evaluated by Pearson correlation coefficients. Abbreviated sampling equations were derived by multiple, stepwise regression analyses performed using AUC12 as the dependent variables. The variance in the strength of association between predicted AUC (AUC(P)) and AUC12 was reflected by linear regression coefficients of multiple determinations.

RESULTS

In 16 patients, AUC12 values were within the range of 44.40 ng x h/mL to 158.01 ng x h/mL (mean = 92.23 +/- 34.97 ng x h/mL). The area of the maximum AUC12 was almost fourfold higher than that of the minimum AUC12. C12 significantly correlated with AUC(12) after the first tarcrolimus oral dose (r = .846, P < .001). C5, C8, and C3 showed better correlations: r = .924, .924, and .911, respectively. From stepwise multiple regression, C5 seemed to be the best predictor of total body exposure to tacrolimus (r = .92, r2 = .85). Alternatively, the concentrations at 5 and 1.5 hours or 5, 1.5, and 3 hours as an abbreviated AUC were as good as a full pharmacokinetic study (r = .97, r2 = .94, and r = .99, r2 = .99, respectively).

CONCLUSIONS

Tacrolimus AUC12 show remarkable interindividual variations after the first oral dose in combination with mycophenolate mofetil and prednisone in Chinese renal transplant recipients. Although C12 is a good predictor of efficacy, C5 might be the best predictor of the first AUC12. A two-point sampling method using C5 and C1.5 or three-point sampling method using C5, C1.5, and C3 might be the best abbreviated AUC for a cost-effective tacrolimus monitoring strategy.

QTL x environment interactions in rice. I. heading date and plant height

One hundred twenty six doubled-haploid (DH) rice lines were evaluated in nine diverse Asian environments to reveal the genetic basis of genotype x environment interactions (GEI) for plant height (PH) and heading date (HD). A subset of lines was also evaluated in four water-limited environments, where the environmental basis of G x E could be more precisely defined. Responses to the environments were resolved into individual QTL x environment interactions using replicated phenotyping and the mixed linear-model approach. A total of 37 main-effect QTLs and 29 epistatic QTLs were identified. On average, these QTLs were detectable in 56% of the environments. When detected in multiple environments, the main effects of most QTLs were consistent in direction but varied considerably in magnitude across environments. Some QTLs had opposite effects in different environments, particularly in water-limited environments, indicating that they responded to the environments differently. Inconsistent QTL detection across environments was due primarily to non- or weak-expression of the QTL, and in part to significant QTL x environment interaction effects in the opposite direction to QTL main effects, and to pronounced epistasis. QTL x environment interactions were trait- and gene-specific. The greater GEI for HD than for PH in rice were reflected by more environment-specific QTLs, greater frequency and magnitude of QTL x environment interaction effects, and more pronounced epistasis for HD than for PH. Our results demonstrated that QTL x environment interaction is an important property of many QTLs, even for highly heritable traits such as height and maturity. Information about QTL x environment interaction is essential if marker-assisted selection is to be applied to the manipulation of quantitative traits.

Genetic differentiation of wild relatives of rice as assessed by RFLP analysis

To study genetic diversity and relationships of wild relatives of rice, 58 accessions of Oryza rufipogon, Oryza nivara, Oryza sativa f. spontanea and the cultivated Oryza sativa, representing a wide range of their distribution, were analyzed using the restriction fragment length polymorphism (RFLP) technique. All 30-used RFLP probes detected polymorphisms among the Oryza accessions, with an average of 3.8 polymorphic fragments per probe. Considerable genetic diversity was scored among the Oryza accessions with a similarity coefficient ranging from 0.28 to 0.93; but the cluster analysis of the accessions did not show an apparent grouping based on the species classification, instead they were scattered randomly in different groups. Noticeably, the Oryza accessions from the same geographic region, or near-by geographic regions, tended to be clustered in the same groups. The indica rice varieties showed relatively high genetic diversity and were scattered in different groups of their wild relatives, but the japonica varieties showed a relatively low variation and formed an independent group. It is concluded from the molecular analytical result that: (1) the four Oryza taxa have a remarkably close relationship and their independent species status need to be carefully reviewed; (2) geographic isolation has played a significant role in the differentiation of the Oryza accessions; therefore, a wide geographic range needs to be covered in collecting wild rice germplasm for ex situ conservation; and (3) the conventional conclusion of indica rice being directly domesticated from its ancestral wild species, and japonica rice being derived from indica, gains support from our data.

[Comparison of the detection of QTL for yield traits in different generations of a rice cross using two mapping approaches]

In the F2 and recombinant inbred populations of Zhenshan 97B/Milyang 46, RFLP linkage maps were constructed to detect QTL for yield and its component traits. Results indicated that QTL having substantial additive effects were generally detected in both F2 and recombinant inbred populations. In addition, the trait performances were measured either based on a single plant or on replicated trials in the recombinant inbred population hardly affected the detection of QTL of higher effects.

[Mapping genes for rice CMS-WA fertility restoration]

In a population consisting of 227 test-crosses of Zhenshan 97A x (Zhenshan 97B x Milyang 46) F6, a linkage map of 115 RFLP markers was constructed and employed to detect QTL for rice CMS-WA (wild abortive cytoplasmic male sterility) fertility restoration. One QTL having major effect, qRf-10, and 3 QTL having minor effects, qRf-1, qRf-7 and qRf-11, were detected. The four genes mainly acted additively with each other, but epistasis was also evident. Two minor QTL, qRf-1 and qRf-11, were significantly interacted with the major gene qRf-10. It was also found that interaction effects among minor QTL varied greatly depending on whether qRf-10 was present. Two other QTL, qSF-1 and qSF-7, were detected, which did not display any effects on fertility restoration. Instead, they showed effects for increasing SF when qRf-10 was present.

Identifying different types of de-differentiated microspores from indica-japonica F(1) hybrids with subspecies-differentiating RFLP probes in rice

The indica, japonica and intermediary types of de-differentiated microspores from indica-japonica F(1) hybrids were identified with 11 subspecies-differentiating RELP probes in rice (Oryza sativa L.). The results showed that the distribution of indica, japonica and intermediary types of de-differentiated microspores could be easily detected in a simple and quick way using the RFLP method. Moreover, the microspores from the same F(1) hybrid but inoculated onto different media, or microspores from different F(1) hybrids when inoculated onto the same medium, often displayed distinctive distribution curves of de-differentiated microspores types, indicating that the media employed in this experiment had high selectivity for the de-differentiation of certain types of microspores. The application of the RELP method to de-differentiated microspore identification is of great theoretical and practical significance in rice doubled-haploid breeding.

RFLP mapping of QTLs for yield and related characters in rice (Oryza sativa L.)

Quantitative triat loci (QTLs) for yield and related traits in rice were mapped based on RFLP maps from two indica/indica F2 populations, Tesanai 2/CB and Waiyin 2/CB. In Tesanai 2/CB, 14 intervals carrying QTLs for eight traits were detected, including 3 for grain weight per plant (GWT), 2 for number of panicles per plant (NP), 2 for number of grains per panicle (NG), 1 for total number of spikelets per panicle (TNS), 1 for spikelet fertility (SF), 3 for 1000-grain weight (TGWT), 1 for spikelet density (SD), and 1 for number of first branches per main panicle. The 3 QTLs for GWT were located on chromosomes 1, 2, and 4, with 1 in each chromosome. The additive effect of the single locus ranged from 2.0 g to 9.1 g. A major gene (np4) for NP was detected on chromosome 4 within the interval of RG143-RG214, about 4cM for RG143, and this locus explained 26.1% of the observed phenotypic variance for NP. The paternal allele of this locus was responsible for reduced panicles per plant (3 panicles per plant). In another population, Waiyin 2/CB, 12 intervals containing QTLs for six of the above-mentioned traits were detected, including 3 for GWT, 2 for each of NP, TNS, TGWT and SD, 1 for SF. Three QTLs for GWT were located on chromosome 1, 4, and 5, respectively. The additive effect of the single locus for GWT ranged from 6.7 g to 8.8 g, while the dominance effect was 1.7-11.5 g. QTL mapping in two populations with a common male parent is compared and discussed.

Identification of a set of RFLP probes for subspecies differentiation in Oryza sativa L

Sixty-eight indica-japonica tester-differentiating RFLP probes were tested in seven indica and seven japonica varieties of rice (Oryza sativa L.) with four enzyme digestions (EcoRI, EcoRV, HindIII and DraI). Twenty-one DNA clones were isolated as indica-japonica subspecies-differentiating probes. A set of 13 probes was established as core probes for subspecies differentiation and a pooled blotting analysis was carried out to facilitate the application of RFLP in rice genetics and breeding practice. A dendrogram of 12 wide-compatibility varieties was constructed based on RFLPs detected by 13 core probes with single enzyme digestions. It was speculated that most RFLPs of indica-japonica differentiating probes were generated by insertions/deletions, which may be of great significance for the origin and differentiation of subspecies in Oryza sativa L.

Nuclear DNA amplification in cultured cells of Oryza sativa L

Highly repeated nuclear DNA sequences from suspension cultured cells of Oryza sativa L. cv. 'Roncarolo' have been cloned in pBR322. Ten clones with specific digestion patterns have been randomly selected. Nine sequences appear to be organized in a clustered tandem array while one is interpersed in the rice genome. The clones have been used to gather information on: (a) their modulation in cultured cells as compared to whole plant and (b) their distribution in different rice cultivars belonging to the Japonica or Indica subspecies of Oryza sativa L. Hybridization with nuclear DNA isolated either from suspension or from seedlings of the 'Roncarolo' cultivar revealed extensive quantitative variations, with most cloned sequences showing amplification (up to 75-fold) in cultured cells. Hybridization with nuclear DNA isolated from seedlings or suspension cultured cells from different cultivars belonging to the Japonica or to the Indica sub-species of O. sativa have shown that (a) amplification also occurs in a similar pattern in the case of DNA from the other tested suspension cultured cell types but not in the case of DNA from seedlings; (b) in some cases the tested sequences show minor but significant variations in different rice accessions.