Single Low Dose Primaquine (0.25mg/kg) Does Not Cause Clinically Significant Haemolysis in G6PD Deficient Subjects

Background

Primaquine is the only drug consistently effective against mature gametocytes of Plasmodium falciparum. The transmission blocking dose of primaquine previously recommended was 0.75mg/kg (adult dose 45mg) but its deployment was limited because of concerns over haemolytic effects in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. G6PD deficiency is an inherited X-linked enzymatic defect that affects an estimated 400 million people around the world with high frequencies (15–20%) in populations living in malarious areas. To reduce transmission in low transmission settings and facilitate elimination of P. falciparum, the World Health Organization now recommends adding a single dose of 0.25mg/kg (adult dose 15mg) to Artemisinin-based Combination Therapies (ACTs) without G6PD testing. Direct evidence of the safety of this low dose is lacking. Adverse events and haemoglobin variations after this treatment were assessed in both G6PD normal and deficient subjects in the context of targeted malaria elimination in a malaria endemic area on the North-Western Myanmar-Thailand border where prevalence of G6PD deficiency (Mahidol variant) approximates 15%.

Methods and Findings

The tolerability and safety of primaquine (single dose 0.25 mg base/kg) combined with dihydroartemisinin-piperaquine (DHA-PPQ) given three times at monthly intervals was assessed in 819 subjects. Haemoglobin concentrations were estimated over the six months preceding the ACT + primaquine rounds of mass drug administration. G6PD deficiency was assessed with a phenotypic test and genotyping was performed in male subjects with deficient phenotypes and in all females. Fractional haemoglobin changes in relation to G6PD phenotype and genotype and primaquine round were assessed using linear mixed-effects models. No adverse events related to primaquine were reported during the trial. Mean fractional haemoglobin changes after each primaquine treatment in G6PD deficient subjects (-5.0%, -4.2% and -4.7%) were greater than in G6PD normal subjects (0.3%, -0.8 and -1.7%) but were clinically insignificant. Fractional drops in haemoglobin concentration larger than 25% following single dose primaquine were observed in 1.8% of the population but were asymptomatic.

Conclusions

The single low dose (0.25mg/kg) of primaquine is clinically well tolerated and can be used safely without prior G6PD testing in populations with high prevalence of G6PD deficiency. The present evidence supports a broader use of low dose primaquine without G6PD testing for the treatment and elimination of falciparum malaria.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01872702","term_id":"NCT01872702"}}NCT01872702     

Elucidation of the protein composition of mouse seminal vesicle fluid

The seminal vesicles are male accessory sex glands that contribute the major portion of the seminal plasma in which mammalian spermatozoa are bathed during ejaculation. In addition to conveying sperm through the ejaculatory duct, seminal vesicle secretions support sperm survival after ejaculation, and influence the female reproductive tract to promote receptivity to pregnancy. Analysis of seminal vesicle fluid (SVF) composition by proteomics has proven challenging, due to its highly biased protein signature with a small subset of dominant proteins and the difficulty of solubilizing this viscous fluid. As such, publicly available proteomic datasets identify only 85 SVF proteins in total. To address this limitation, we report a new preparative methodology involving sequential solubilization of mouse SVF in guanidine hydrochloride, acetone precipitation, and analysis by label-free mass spectrometry. Using this strategy, we identified 126 SVF proteins, including 83 previously undetected in SVF. Members of the seminal vesicle secretory protein family were the most abundant, accounting for 79% of all peptide spectrum matches. Functional analysis identified inflammation and formation of the vaginal plug as the two most prominent biological processes. Other notable processes included modulation of sperm function and regulation of the female reproductive tract immune environment. Together, these findings provide a robust methodological framework for future SVF studies and identify novel proteins with potential to influence both male and female reproductive physiology.     

Contrasting patterns of genetic structure and phylogeography in the marine agarophytes Gelidiophycus divaricatus and G. freshwateri (Gelidiales,Rhodophyta) from East Asia

The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species.     

Anaerobic degradation of benzene in BTX mixtures dependent on sulfate reduction

Abstract Enrichment cultures from marine sediments mineralized benzene while using sulfate as the terminal electron acceptor. Parallel cultures using river marsh sediment displayed no activity. Mineralization was confirmed by release of ¹⁴CO₂ from radiolabeled benzene. The dependence on sulfate reduction was demonstrated by stoichiometric balances and the use of specific inhibitors. This work supports recent observations that anaerobic benzene degradation takes place coupled to sulfate reduction.     

Stabilization of the E3 ubiquitin ligase Nrdp1 by the deubiquitinating enzyme USP8

Nrdp1 is a RING finger-containing E3 ubiquitin ligase that physically interacts with and regulates steady-state cellular levels of the ErbB3 and ErbB4 receptor tyrosine kinases and has been implicated in the degradation of the inhibitor-of-apoptosis protein BRUCE. Here we demonstrate that the Nrdp1 protein undergoes efficient proteasome-dependent degradation and that mutations in its RING finger domain that disrupt ubiquitin ligase activity enhance stability. These observations suggest that Nrdp1 self-ubiquitination and stability could play an important role in regulating the activity of this protein. Using affinity chromatography, we identified the deubiquitinating enzyme USP8 (also called Ubpy) as a protein that physically interacts with Nrdp1. Nrdp1 and USP8 could be coimmunoprecipitated, and in transfected cells USP8 specifically bound to Nrdp1 but not cbl, a RING finger E3 ligase involved in ligand-stimulated epidermal growth factor receptor down-regulation. The USP8 rhodanese and catalytic domains mediated Nrdp1 binding. USP8 markedly enhanced the stability of Nrdp1, and a point mutant that disrupts USP8 catalytic activity destabilized endogenous Nrdp1. Our results indicate that Nrdp1 is a specific target for the USP8 deubiquitinating enzyme and are consistent with a model where USP8 augments Nrdp1 activity by mediating its stabilization.     

Strategies for a successful corrective Asian blepharoplasty after previously failed revisions

Asian blepharoplasty, although a common procedure, has a relatively high rate of complications. Subtle imperfections and more serious iatrogenic complications often require immediate attention by the aesthetic surgeon. After attempted correction of the deformities, residual problems or new ones can arise. Blepharoptosis, supratarsal depression, an excessively high or low crease, a short or discontinuous crease, multiple creases, and asymmetric creases are the most commonly encountered complications that require special attention in this group, which has already undergone more than one surgical procedure. Between January of 1996 and December of 2002, 168 Asian blepharoplasty revisions were performed by one surgeon (S. H.-T. Chen); of these, 36 patients (21 percent) had previously undergone failed revisions. This subgroup of patients consisted of six with blepharoptosis, six with asymmetrical eyelid creases, three with supratarsal depressions, three with high creases, two with short creases, and 16 with combinations of these deformities. The results were graded as excellent, good, fair, or poor, based on the symmetry of the eyelids, palpebral fissures, crease heights, lengths, shapes, eyelid fullness, and overall aesthetics of the final outcome. A survey was performed of patient and surgeon satisfaction and factored into the grading system. With an average follow-up period of 16 months (6 to 60 months), 22 patients (61 percent) were found to have excellent results, 10 (28 percent) had good results, two (5.6 percent) had fair results, and two (5.6 percent) had poor results. Corrective procedures after failed revision Asian blepharoplasty require special strategic considerations because of the presence of extensive scarring and inadequate skin, muscle, and preaponeurotic fat and because of the occasional presence of dehiscence of the levator aponeurosis. By using careful preoperative evaluation, accurate measurements, precise preoperative planning, intraoperative fat repositioning or grafting, skin excision or redraping, and proper placement of anchoring sutures, successful outcomes can be achieved. The authors evaluate the outcomes and detail the surgical procedures that were used to achieve successful outcomes in this particularly challenging group of patients.     

The development of new bicyclic pyrazole-based cytokine synthesis inhibitors

4-Aryl-5-pyrimidyl-based cytokine synthesis inhibitors of TNF-alpha production, which contain a novel bicyclic pyrazole heterocyclic core, are described. Many of these inhibitors showed low nanomolar activity against LPS-induced TNF-alpha production in a THP-1 cell-based assay and against human p38 alpha MAP kinase in an isolated enzyme assay. The X-ray crystal structure of a bicyclic pyrazole inhibitor co-crystallized with mutated p38 (mp38) is presented.     

Nanos and Pumilio are essential for dendrite morphogenesis in Drosophila peripheral neurons

Much attention has focused on dendritic translational regulation of neuronal signaling and plasticity. For example, long-term memory in adult Drosophila requires Pumilio (Pum), an RNA binding protein that interacts with the RNA binding protein Nanos (Nos) to form a localized translation repression complex essential for anterior-posterior body patterning in early embryogenesis. Whether dendrite morphogenesis requires similar translational regulation is unknown. Here we report that nos and pum control the elaboration of high-order dendritic branches of class III and IV, but not class I and II, dendritic arborization (da) neurons. Analogous to their function in body patterning, nos and pum require each other to control dendrite morphogenesis, a process likely to involve translational regulation of nos itself. The control of dendrite morphogenesis by Nos/Pum, however, does not require hunchback, which is essential for body patterning. Interestingly, Nos protein is localized to RNA granules in the dendrites of da neurons, raising the possibility that the Nos/Pum translation repression complex operates in dendrites. This work serves as an entry point for future studies of dendritic translational control of dendrite morphogenesis.