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Background: The Democratic Republic of the Congo (DRC) has one of the highest neonatal death rates (between 14% and 28%) in the world. In the DRC, neonatal sepsis causes 15.6% of this mortality, but data on the bacterial etiology and associated drug susceptibility are lacking., Methods: Hemocultures of 150 neonates with possible early-onset neonatal sepsis (pEOS) were obtained at the Hôpital Provincial Général de Référence de Bukavu (Bukavu, DRC). The newborns with pEOS received an empirical first-line antimicrobial treatment (ampicillin, cefotaxime, and gentamicin) based on the synopsis of international guidelines for the management of EOS that are in line with World Health Organization (WHO) recommendations. Isolates were identified using matrix-assisted laser desorption/ ionization time-of-flight mass spectrophotometry. Antibiotic resistance was assessed using the disk diffusion method., Results: Fifty strains were obtained from 48 patients and identified. The 3 most prevalent species were Enterobacter cloacae complex (42%), Klebsiella pneumoniae (18%), and Serratia marcescens (12%). Enterobacter cloacae isolates were resistant to all first-line antibiotics. All K. pneumoniae and S. marcescens isolates were resistant to ampicillin, and the majority of the K. pneumoniae and half of the S. marcescens isolates were resistant to both cefotaxime and gentamicin. All E. cloacae complex strains, 89% of K. pneumoniae, and half of S. marcescens had an extended-spectrum ß-lactamase phenotype., Conclusions: The most prevalent pathogens causing EOS in Bukavu were E. cloacae complex, K. pneumoniae, and S. marcescens. Most of these isolates were resistant to the WHO-recommended antibiotics., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

The spatiotemporal pattern of deposition, final amount, and relative abundance of oleic acid ( cis -ω-9 C18:1) and its derivatives in the different lipid fractions of the seed of Arabidopsis ( Arabidopsis thaliana ) indicates that omega-9 monoenes are synthesized at high rates in this organ. Accordingly, we observed that four Δ9 stearoyl-ACP desaturase (SAD)-coding genes ( FATTY ACID BIOSYNTHESIS2 [ FAB2 ], ACYL-ACYL CARRIER PROTEIN5 [ AAD5 ], AAD1 , and AAD6 ) are transcriptionally induced in seeds. We established that the three most highly expressed ones are directly activated by the WRINKLED1 transcription factor. We characterized a collection of 30 simple, double, triple, and quadruple mutants affected in SAD-coding genes and thereby revealed the functions of these desaturases throughout seed development. Production of oleic acid by FAB2 and AAD5 appears to be critical at the onset of embryo morphogenesis. Double homozygous plants from crossing fab2 and aad5 could never be obtained, and further investigations revealed that the double mutation results in the arrest of embryo development before the globular stage. During later stages of seed development, these two SADs, together with AAD1, participate in the elaboration of the embryonic cuticle, a barrier essential for embryo-endosperm separation during the phase of invasive embryo growth through the endosperm. This study also demonstrates that the four desaturases redundantly contribute to storage lipid production during the maturation phase., (© 2020 American Society of Plant Biologists. All rights reserved.)

Flavonoids are secondary metabolites that fulfil a multitude of functions during the plant life cycle. In Arabidopsis proanthocyanidins (PAs) are flavonoids that specifically accumulate in the innermost integuments of the seed testa (i.e. endothelium), as well as in the chalaza and micropyle areas, and play a vital role in protecting the embryo against various biotic and abiotic stresses. PAs accumulation in the endothelium requires the activity of the MADS box transcription factor TRANSPARENT TESTA (TT) 16 (ARABIDOPSIS B-SISTER/AGAMOUS-LIKE 32) and the UDP-glycosyltransferase TT15 (UGT80B1). Interestingly tt16 and tt15 mutants display a very similar flavonoid profiles and patterns of PA accumulation. By using a combination of genetic, molecular, biochemical, and histochemical methods, we showed that both TT16 and TT15 act upstream the PA biosynthetic pathway, but through two distinct genetic routes. We also demonstrated that the activity of TT16 in regulating cell fate determination and PA accumulation in the endothelium is required in the chalaza prior to the globular stage of embryo development. Finally this study provides new insight showing that TT16 and TT15 functions extend beyond PA biosynthesis in the inner integuments of the Arabidopsis seed coat., (© The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

Ten Belgian travelers returned from Mali with a Schistosoma haematobium-Schistosoma bovis hybrid infection, confirmed by DNA sequencing from eggs. Clinical symptoms and laboratory findings resembled those of classic acute schistosomiasis, but the detected eggs were morphologically unusual., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

Cultures of human epithelial cells (keratinocytes) are used as an additional surgical tool to treat critically burnt patients. Initially, the production environment of keratinocyte grafts was regulated exclusively by national regulations. In 2004, the European Tissues and Cells Directive 2004/23/EC (transposed into Belgian Law) imposed requirements that resulted in increased production costs and no significant increase in quality and/or safety. In 2007, Europe published Regulation (EC) No. 1394/2007 on Advanced Therapy Medicinal Products. Overnight, cultured keratinocytes became (arguably) 'Advanced' Therapy Medicinal Products to be produced as human medicinal products. The practical impact of these amendments was (and still is) considerable. A similar development appears imminent in bacteriophage therapy. Bacteriophages are bacterial viruses that can be used for tackling the problem of bacterial resistance development to antibiotics. Therapeutic natural bacteriophages have been in clinical use for almost 100 years. Regulators today are framing the (re-)introduction of (natural) bacteriophage therapy into 'modern western' medicine as biological medicinal products, also subject to stringent regulatory medicinal products requirements. In this paper, we look back on a century of bacteriophage therapy to make the case that therapeutic natural bacteriophages should not be classified under the medicinal product regulatory frames as they exist today. It is our call to authorities to not repeat the mistake of the past., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Type III secretion system (T3SS) in Pseudomonas aeruginosa is associated with poor clinical outcome in acute infections. T3SS allows for injection of bacterial exotoxins (e.g. ExoU or ExoS) into the host cell, causing cytotoxicity. It also activates the cytosolic NLRC4 inflammasome, activating caspase-1, inducing cytotoxicity and release of mature IL-1β, which impairs bacterial clearance. In addition, flagellum-mediated motility has been suggested to also modulate inflammasome response and IL-1β release. Yet the capacity of clinical isolates to induce IL-1β release and its relation with cytotoxicity have never been investigated. Using 20 clinical isolates from acute infections with variable T3SS expression levels and human monocytes, our aim was to correlate IL-1β release with toxin expression, flagellar motility and cytotoxicity. ExoU-producing isolates caused massive cell death but minimal release of IL-1β, while those expressing T3SS but not ExoU (i.e. expressing ExoS or no toxins) induced caspase-1 activation and IL-1β release, the level of which was correlated with cytotoxicity. Both effects were prevented by a specific caspase-1 inhibitor. Flagellar motility was not correlated with cytotoxicity or IL-1β release. No apoptosis was detected. Thus, T3SS cytotoxicity is accompanied by a modification in cytokine balance for P. aeruginosa clinical isolates that do not express ExoU., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Chronic Pseudomonas aeruginosa infections are the main cause of morbidity among patients with cystic fibrosis (CF) due to persistent lung inflammation caused by interaction between this bacterium and the immune system. Longitudinal studies of clonally related isolates of a dominant CF clone have indicated that genome reduction frequently occurs during adaptation of P. aeruginosa in the CF lung. In this study, we have evaluated the P. aeruginosa population structure of patients attending the Universitair Ziekenhuis Brussel (UZ Brussel) CF reference center using a combination of genotyping methods. Although the UZ Brussel P. aeruginosa CF population is characterized by the absence of a dominant CF clone, some potential interpatient transmissions could be detected. Interestingly, one of these clones showed deletion of the alternative type I ferripyoverdine receptor gene fpvB. Furthermore, we found that several other TonB-dependent receptors are deleted as well. The genome of one potentially transmissible CF clone was sequenced, revealing large deleted regions including all type III secretion system genes and several virulence genes. Remarkably, a large number of deleted genes are shared between the P. aeruginosa CF clone described in this study and isolates belonging to the dominant Copenhagen CF DK2 clone, suggesting parallel evolution., (© 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.)

Modelling and simulation are increasingly used as tools in the study of plant growth and developmental processes. By formulating experimentally obtained knowledge as a system of interacting mathematical equations, it becomes feasible for biologists to gain a mechanistic understanding of the complex behaviour of biological systems. In this review, the modelling tools that are currently available and the progress that has been made to model plant development, based on experimental knowledge, are described. In terms of implementation, it is argued that, for the modelling of plant organ growth, the cellular level should form the cornerstone. It integrates the output of molecular regulatory networks to two processes, cell division and cell expansion, that drive growth and development of the organ. In turn, these cellular processes are controlled at the molecular level by hormone signalling. Therefore, combining a cellular modelling framework with regulatory modules for the regulation of cell division, expansion, and hormone signalling could form the basis of a functional organ growth simulation model. The current state of progress towards this aim is that the regulation of the cell cycle and hormone transport have been modelled extensively and these modules could be integrated. However, much less progress has been made on the modelling of cell expansion, which urgently needs to be addressed. A limitation of the current generation models is that they are largely qualitative. The possibilities to characterize existing and future models more quantitatively will be discussed. Together with experimental methods to measure crucial model parameters, these modelling techniques provide a basis to develop a Systems Biology approach to gain a fundamental insight into the relationship between gene function and whole organ behaviour.

Proline accumulation is one of the most common responses of plants to environmental constraints. Thellungiella halophila/salsuginea, a model halophyte, accumulates high levels of proline in response to abiotic stress and in the absence of stress. Recently, lipid signaling pathways have been shown to be involved in the regulation of proline metabolism in Arabidopsis thaliana. Here we investigated the relationship between lipid signaling enzymes and the level of proline in T. salsuginea. Inhibition of phospholipase C (PLC) enzymes by the specific inhibitor U73122 demonstrated that proline accumulation is negatively controlled by PLCs in the absence of stress and under moderate salt stress (200 mM NaCl). The use of 1-butanol to divert some of the phospholipase D (PLD)-derived phosphatidic acid by transphosphatidylation revealed that PLDs exert a positive control on proline accumulation under severe stress (400 mM NaCl or 400 mM mannitol) but have no effect on its accumulation in non-stress conditions. This experimental evidence shows that positive and negative lipid regulatory components are involved in the fine regulation of proline metabolism. These signaling pathways in T. salsuginea are regulated in the opposite sense to those previously described in A. thaliana, revealing that common signaling components affect the physiology of closely related glycophyte and salt-tolerant plants differently.

The detection of schistosomiasis cases among Belgian military personnel returning from a mission in the Democratic Republic of Congo (DRC) prompted a nested case-control study of all military personnel deployed in the DRC between 2005 and 2008 to identify all infections and to start appropriate treatment. Of 197 patients exposed at Lake Tanganyika in the Kalemie area of DRC, 49 (24.9%) were diagnosed with schistosomiasis. Swimming was significantly more frequent than wading in the seropositive group than in the seronegative group (88.9% vs. 73.6%; odds ratio [OR], 2.86; 95% confidence interval [CI], 0.97-9.01). Thirty-one of 49 patients (63.3%) were symptomatic; including skin problems in 34.7%, respiratory symptoms in 12.2%, fever in 14.3%, and 51.0% with gastrointestinal problems. Median eosinophil counts were significantly higher in seropositive patients (375 vs. 138 per tL; Wilcoxon rank sum test [Ws] = 10,559.00; p < 0.01; r = -0.49). In total, 20 (40.8%) of the 49 patients were treated for symptomatic infections and the remainder for asymptomatic schistosomiasis. Our study emphasizes the need for active systematic post-tropical screening in military personnel after deployment to Schistosoma-endemic regions of the world.

Background: The efficacy and safety of photodynamic therapy for superficial bladder cancer depend on tumor-selective accumulation of the photosensitizer. Bladder transitional-cell carcinoma cells overexpress the transferrin receptor on their surface. We examined whether transferrin-mediated liposomal targeting of the photosensitizer aluminum phthalocyanine tetrasulfonate (AlPcS4) is an effective strategy to attain tumor-selective accumulation of this compound when applied intravesically., Methods: AlPcS4 was stably encapsulated in unconjugated liposomes (Lip-AlPcS4) or transferrin-conjugated liposomes (Tf-Lip-AlPcS4). The accumulation of free AlPcS4, Lip-AlPcS4, and Tf-Lip-AlPcS4 in human AY-27 transitional-cell carcinoma cells and in an orthotopic rat bladder tumor model was visualized by fluorescence microscopy. In vitro AlPcS4 accumulation was quantified by fluorescence measurements following drug extraction, and the photodynamic efficacy of AlPcS4 was measured in a clonogenic assay. All statistical tests were two-sided., Results: AY-27 cells incubated with Tf-Lip-AlPcS4 had much higher intracellular AlPcS4 levels than AY-27 cells incubated with Lip-AlPcS4 (384.1 versus 3.7 microM; difference = 380.4 microM, 95% CI = 219.4 to 541.3; P = .0095). Among rats bearing AY-27 cell-derived bladder tumors, intravesical instillation with Tf-Lip-AlPcS4 resulted in mean AlPcS4 fluorescence in tumoral tissue, normal urothelium, and submucosa/muscle of 77.9 fluorescence units (fu) (95% CI = 69.1 to 86.8 fu), 4.3 fu (95% CI = 4.0 to 4.5 fu), and 1.0 (95% CI = 0.1 to 1.9 fu), respectively, whereas instillation of free AlPcS4 resulted in nonselective accumulation throughout the whole bladder wall, and Lip-AlPcS4 instillation resulted in no tissue accumulation. Photodynamic therapy of AY-27 cells incubated with Lip-AlPcS4 resulted in cell viabilities greater than 90% for all concentrations and incubation times tested; photodynamic therapy of cells incubated with 1 muM Tf-Lip-AlPcS4 or AlPcS4 resulted in cell viabilities of 0.19% (95% CI = 0.02% to 0.36%) and 1.32% (95% CI = 0.46% to 2.19%), respectively. Higher concentrations of either AlPcS4 or Tf-Lip-AlPcS4 resulted in cell kills of more than 3 logs., Conclusions: Transferrin-mediated liposomal targeting of photosensitizing drugs is a promising potential tool for photodynamic therapy of superficial bladder tumors.

We have developed a novel coincidence cloning strategy, termed Coincidence Painting, which enables the rapid generation of large numbers of region specific sequences. Coincidence Painting utilises Degenerate Oligonucleotide Primed PCR (DOP-PCR) amplification of flow sorted derivative translocation chromosomes. The PCR products are hybridised in situ onto specific flow sorted chromosomes for coincident sequence selection. Eluted and reamplified material is then cloned using a novel insert end revelation and ligation technique. Cloned inserts range in size from 150-1300 bps of which approximately 54% appear to be single copy sequences. The cloning method permits the excision of vector free probe for library hybridisation screening and the small insert size facilitates analysis for the generation of sequence tagged sites (STSs). We have used such clones successfully for YAC screening by PCR and for cosmid screening by filter hybridisation. This new methodology should allow the rapid saturation with probes of regions defined by specific translocation breakpoints.