Risk for Hepatitis E Virus Transmission by Solvent/Detergent–Treated Plasma

Hepatitis E has emerged as a major transfusion-transmitted infectious risk. Two recipients of plasma from 2 lots (A and B) of pooled solvent/detergent–treated plasma were found to be infected by hepatitis E virus (HEV) that was determined to have been transmitted by the solvent/detergent–treated plasma. HEV RNA viral loads were 433 IU in lot A and 55 IU in lot B. Retrospective studies found that 100% (13/13) of evaluable lot A recipients versus 18% (3/17) of evaluable lot B recipients had been infected by HEV (p<0.001), albeit not necessarily at time of transfusion. Among evaluable recipients, 86% with a transfused HEV RNA load >50,000 IU were infected, most likely by the HEV-containing solvent/detergent–treated plasma, versus only 7% with a transfused HEV RNA load <50,000 IU (p<0.001). Overall, solvent/detergent–treated plasma might harbor HEV. Such an occurrence might result in a dose-dependent risk for transfusion-transmitted hepatitis E.     

布鲁氏菌分子诊断与分型技术研究进展

布鲁氏菌病是全球最常见的人畜共患病之一。布鲁氏菌病大多是由羊种布鲁菌感染所致,其次是牛种和猪种。在过去的20年里,人类和动物布病的防控已经取得了较大进展。然而,由于其非特异性的临床表现,控制和根除布病仍然面临巨大的挑战。随着20世纪90年代以来分子生物学技术的快速发展,分子生物学检测方法已被国内外用来迅速检测研究布鲁氏菌,同时由于全球数据共享的数据库的建立,使得全球对于布病的研究越来越深入。     

Utility of rotational thromboelastometry in total hip replacement revision surgery (case-control study)

Total hip replacement revision surgery is accompanied by significant blood loss. Using rotational thrombelastometry (ROTEM) perioperatively to diagnose coagulopathy may help to provide rapid aimed therapy and thus decrease blood loss and the consumption of transfusion products. The aim of this case-control study was to find out whether point of care using of ROTEM may reduce blood loss and the consumption of blood transfusion products in hip replacement revision surgery.Data were prospectively collected from patients who underwent hip replacement revision surgery in the period 2017 to 2018 when the management of bleeding and coagulopathy was based on the results of ROTEM. Data were compared with a group of historical controls for the period 2015 to 2016 when bleeding and coagulopathy management was not based on ROTEM results. The consumption of blood transfusion products and perioperative blood loss were compared between the groups.The total number of analyzed patients was 90. Forty five patients were analyzed in the ROTEM group and the same number of patients were analyzed in the non-ROTEM group. Significantly decreased perioperative consumption of fresh frozen plasma and packed red blood cells was found in the ROTEM, as well as decreased perioperative blood loss comparing to non-ROTEM group. All data were statistically different with P < .05.Perioperative management of bleeding and coagulopathy based on the results of ROTEM during hip replacement revision surgery seems to help to decrease perioperative blood loss and the consumption of blood transfusion products, especially fresh frozen plasma.     

Retrospective comparison between non-treponemal and treponemal tests for screening of blood donors for syphilis and their correlation with donor history in a tertiary care teaching hospital

Background and objectivesTreponemal tests provide advantage of better detection during early, late and latent stages of syphilis with equal or higher sensitivity & specificity in comparison to non-treponemal tests. The objective of the present study was to analyse the level of concordance between treponemal and non-treponemal tests for donor screening and to correlate them with donor history.Materials and methodsRetrospective analysis of syphilis screening by treponemal (Chemiluminescence & TPHA) and non-treponemal tests (RPR) was done and donor history for high-risk behaviour and factors associated with false positivity were collected from post-donation counselling and collected data was coded and analysed.ResultsAmongst the 12,000 donors screened, reactivity rate by RPR, TPHA and Chemiluminescence was 0.45%, 0.8% and 1.17% respectively. There was discordance of 62% and 32% for reactive results by RPR and TPHA respectively when compared with Chemiluminescence. History of high-risk behaviour was present in ∼ 50% and 15% of donors with discordant results by RPR and TPHA respectively. Of 34 donors who were reactive only by Chemiluminescence and were followed up, 15% had history of high-risk behaviour and 56% had factors associated with false reactivity.ConclusionTreponemal tests showed high syphilis reactivity amongst blood donors as compared to non-treponemal tests most likely due to their ability to detect early, late and latent syphilis cases. This may confer added transfusion safety in centres dependent on replacement donors without NAT testing by identifying donors with high-risk history with negligible increase in discard rate due to false reactivity.     

Are nontreponemal tests suitable for monitoring syphilis treatment efficacy? Evidence from rabbit infection models

ObjectivesWe aimed to characterize kinetics of non-treponamal antibody titres during the natural course of syphilis and explore their roles in monitoring syphilis treatment efficacy.MethodsSixty New Zealand white male rabbits were challenged with Nichols or Amoy Treponema pallidum strains, and the rapid plasma reagin (RPR) test was performed to quantify non-treponemal antibody titres during the infection course. Viable T. pallidum in the challenged rabbits was assessed with rabbit infectivity tests.ResultsThe RPR titres of the Nichols or Amoy strain between no benzathine penicillin G (BPG) and BPG treatment subgroups displayed a similar trend: first ascending and then descending. Compared with baseline, the proportions of fourfold decline in RPR titres in the Nichols or Amoy group presented a similar result on days 30, 60 and 180 between the no BPG and BPG treatment subgroups (0%, 0/5; 80%, 4/5; 100%, 5/5; vs. 0%, 0/5; 80%, 4/5; 100%, 5/5; p 0.999; 0%, 0/5; 80%, 4/5; 80%, 4/5; vs. 40%, 2/5; 100%, 5/5; 100%, 5/5; p 0.098, respectively). Compared with the maximum baseline titre, the proportion of fourfold decline in PRR titre also showed a similar result in the two groups on days 30, 60 and 180 between the no BPG and the BPG treatment subgroups (0%, 0/5; 100%, 5/5; 100%, 5/5, vs. 40%, 2/5; 100%, 5/5; 100%, 5/5; p 0.129; 0%, 0/5; 100%, 5/5; 100%, 5/5, vs. 80%, 4/5; 100%, 5/5; 100%, 5/5; p 0.091, respectively. Moreover, regardless of whether the RPR titres presented a fourfold decline, viable T. pallidum could be detected in untreated rabbits' lymph nodes at 30, 60 and 180 days post infection, while viable T. pallidum was not detected in any of the treated rabbits' lymph nodes.ConclusionsThe RPR titre increased and then decreased (even became negative) during the natural course of syphilis, similar to that seen after BPG treatment. The RPR tetre is thus a questionable indicator of syphilis treatment efficacy.     

Study of Silica‐Supported Chromocene Catalysts for Ethylene Polymerization

Ultrahigh molecular weight polyethylene (UHMWPE) has drawn great interest from researchers because it possesses many excellent properties such as superb strength and impact resistance, which other polyolefin cannot achieve. A silica‐supported chromocene catalyst, for the production of UHMWPE, is successfully developed. The polyethylene (PE) produced by the chromocene catalyst can achieve a molecular weight (MW) of over 3 × 10⁶ g mol^?1 with narrow molecular weight distribution (MWD) a value of approximately three. The activity calculated by Cr per unit reaches the maximum when the loading of Cr is 1.7 wt%. With the increasing loading of chromocene, the MW shows a small increase and the MWD becomes narrower. The chromocene catalyst for ethylene polymerization also shows a significant hydrogen response. With 0.01 MPa hydrogen added into the ethylene polymerization, the MW of the PE decreases immensely to only 0.7 × 10⁶ g mol^?1 and the MWD is broadened from <3 to ≈12. If the amount of hydrogen increases, the MW continues to decrease and the MWD becomes wider. The MW of the PE produced by the chromocene catalyst can be regulated easily by adjusting the amount of hydrogen.     

Metabolism of deltamethrin and cis- and trans-permethrin by rat and human liver microsomes,liver cytosol and plasma preparations

1. The metabolism of deltamethrin (DLM), cis-permethrin (CPM) and trans-permethrin (TPM) was studied in liver microsomes, liver cytosol and plasma from male Sprague–Dawley rats aged 15, 21 and 90 days and from adult humans.

2. DLM and CPM were metabolised by rat hepatic microsomal cytochrome P450 (CYP) enzymes and to a lesser extent by microsomal and cytosolic carboxylesterase (CES) enzymes, whereas TPM was metabolised to a greater extent by CES enzymes.

3. In human liver, DLM and TPM were mainly metabolised by CES enzymes, whereas CPM was metabolised by CYP and CES enzymes.

4. The metabolism of pyrethroids by cytosolic CES enzymes contributes to the overall hepatic clearance of these compounds.

5. DLM, CPM and TPM were metabolised by rat, but not human, plasma CES enzymes.

6. This study demonstrates that the ability of male rats to metabolise DLM, CPM and TPM by hepatic CYP and CES enzymes and plasma CES enzymes increases with age. In all instances, apparent intrinsic clearance values were lower in 15 than in 90?day old rats. As pyrethroid-induced neurotoxicity is due to the parent compound, these results suggest that DLM, CPM and TPM may be more neurotoxic to juvenile than to adult rats.