Using genomics to examine the persistence of Streptococcus pneumoniae serotype 19A in Ireland and the emergence of a sub-clade associated with vaccine failures.

BACKGROUND: Streptococcus pneumoniae serotype 19A remains a significant cause of invasive pneumococcal disease (IPD) in Ireland despite the successful introduction of a 13-valent pneumococcal conjugate vaccine (PCV13) in 2010 which reduced the overall incidence of IPD in children. METHODS: Invasive Streptococcus pneumoniae serotype 19A isolates from the Irish reference laboratory between 2007-08 and 2017-18 were analysed using whole genome sequencing (WGS) to investigate the persistence of this vaccine-preventable serotype. We compared the entire national 19A collection to other international collections using a standardised nomenclature of Global Pneumococcal Sequencing Clusters (GPSC). RESULTS: Expansion of GPSCs and clonal complexes (CCs) may have been associated with vaccine introduction and antimicrobial prescribing policies. A sub-clade of GPSC1-CC320 (n = 25) unique to Ireland, included five of the ten vaccine failures/breakthrough cases identified (p = 0.0086). This sub-clade was not observed in a global GPSC1-CC320 collection. All isolates within the sub-clade (n = 25) contained a galE gene variant rarely observed in a global pneumococcal collection (n = 37/13454, p < 0.001) nor within GPSC1-CC320 (n = 19/227) (p < 0.001). The sub-clade was estimated to have emerged at the start of the PCV-vaccine era (ancestral origin 2000, range 1995-2004) and expanded in Ireland, with most isolated after PCV13 introduction (n = 24/25). CONCLUSIONS: The identification of a sub-clade/variant of serotype 19A highlights the benefit of using WGS to analyse genotypes associated with persistence of a preventable serotype of S. pneumoniae. Particularly as this sub-clade identified was more likely to be associated with IPD in vaccinated children than other 19A genotypes. It is possible that changes to the galE gene, which is involved in capsule production but outside of the capsular polysaccharide biosynthesis locus, may affect bacterial persistence within the population. Discrete changes associated with vaccine-serotype persistence should be further investigated and may inform vaccine strategies.

Electricity production from municipal solid waste using microbial fuel cells.

The organic content of municipal solid waste has long been an attractive source of renewable energy, mainly as a solid fuel in waste-to-energy plants. This study focuses on the potential to use microbial fuel cells to convert municipal solid waste organics into energy using various operational conditions. The results showed that two-chamber microbial fuel cells with carbon felt and carbon felt allocation had a higher maximal power density (20.12 and 30.47 mW m(-2) for 1.5 and 4 L, respectively) than those of other electrode plate allocations. Most two-chamber microbial fuel cells (1.5 and 4 L) had a higher maximal power density than single-chamber ones with corresponding electrode plate allocations. Municipal solid waste with alkali hydrolysis pre-treatment and K3Fe(CN)6 as an electron acceptor improved the maximal power density to 1817.88 mW m(-2) (~0.49% coulomb efficiency, from 0.05-0.49%). The maximal power density from experiments using individual 1.5 and 4 L two-chamber microbial fuel cells, and serial and parallel connections of 1.5 and 4 L two-chamber microbial fuel cells, was found to be in the order of individual 4 L (30.47 mW m(-2)) > serial connection of 1.5 and 4 L (27.75) > individual 1.5 L (20.12) > parallel connection of 1.5 and 4 L (17.04) two-chamber microbial fuel cells . The power density using municipal solid waste microbial fuel cells was compared with information in the literature and discussed.

Effects of different SRT on anaerobic digestion of MSW dosed with various MSWI ashes.

This study investigated different solid retention time (SRT) on municipal solid waste (MSW) anaerobic digestion with various MSW incinerator fly ash (FA) and bottom ash (BA) addition. Results showed that biogas production rates (BPRs, ≈ 200 to ≈ 400 mL/gVS) with organic loading rate of ≈ 0.053 gVS/gVS(reactor) (Day 1-435, SRT 20 days, SRT20) at FA 1g/d (FA1), BA 12 g/d (BA12) and BA 24 g/d (BA24) dosed bioreactors increased after adaptation. BPRs with SRT10 and SRT5 decreased while BPRs with SRT40 showed to increase compared to initial BPRs (≈ 200 mL/gVS) with SRT20. SRT5 operation reduced the BPRs (≈ 10 - ≈ 90 mL/gVS) significantly and only BA12 and BA24 dosed bioreactors could recover the BPRs (≈ 100 - ≈ 200 mL/gVS) after SRT20 operation (Day 613-617) compared to FA1 and FA3 and control. Released levels of Co, Mo and W at BA12 and BA24 dosed bioreactors showed most potential to improve MSW anaerobic digestion.

Effects of micro-nano and non micro-nano MSWI ashes addition on MSW anaerobic digestion.

This study aims at investigating the effects of micro-nano municipal solid waste (MSW) incinerator (MSWI) fly ash (FA) and bottom ash (BA) on the MSW anaerobic digestion. Results showed that suitable micro-nano and non micro-nano MSWI ashes addition (FA/MSW 3, 6, 18 and 30 g g(-1) VS and BA/MSW 12, 36, 60 and 120 g g(-1) VS) could enhance the biogas production compared to the control. It was particularly found to have the highest biogas production at the micro-nano MSWI BA/MSW ratio of 36 g g(-1) VS (∼193 mL g(-1) VS MSW, ∼3.5 times to the control). Micro-nano MSWI FA and BA added bioreactors had the higher biogas production than the corresponding non micro-nano MSWI FA and BA added ones. Suitable MSWI ashes addition could improve the biogas production due to the released metals levels suitable for the MSW anaerobic digestion particularly found in the micro-nano added bioreactors.

Emergency transcatheter embolisation of superior mesenteric arteriovenous fistula complicated by recurrent haematemesis.

Arterioportal fistulas are rare. Superior mesenteric arteriovenous fistula is uncommon and usually observed in patients who have abdominal trauma or have undergone abdominal surgery. If untreated, mesenteric arteriovenous fistula is potentially fatal due to portal hypertension with potential complications such as massive variceal bleeding or progressive liver failure. We report a 50-year-old Chinese man who had a history of abdominal surgery and presented with recurrent haematemesis. He was diagnosed by multidetector computed tomography to have a superior mesenteric arteriovenous fistula. Subsequently, he presented with acute bleeding oesophageal varices. Emergency transarterial embolisation was successfully performed to arrest the bleeding.

Presynaptic mechanisms underlying cannabinoid inhibition of excitatory synaptic transmission in rat striatal neurons.

The striatum is a crucial site of action for the motor effects of cannabinoids (CBs). However, the electrophysiological consequences of activation of CB receptors on the striatal neurons have not been established. Here we report for the first time that the cannabimimetic aminoalkylindole WIN 55,212-2 and the endogenous cannabinoid anandamide substantially depress corticostriatal glutamatergic synaptic transmission onto striatal neurons in the brain slice preparation. The selective CB1 receptor antagonist SR 141716 effectively reversed this inhibition. WIN 55,212-2 significantly increased the paired-pulse facilitation of synaptically evoked EPSCs, while having no effect on the sensitivity of postsynaptic neurons to [alpha]-amino-3-hydroxy-5-methylisoxazole-4-propionic acid. WIN 55,212-2 also reduced the frequency of spontaneous, action potential-dependent EPSCs (sEPSCs) without altering their amplitude distribution. Superfusion of WIN 55,212-2 elicited a membrane hyperpolarization accompanied by a decrease in input resistance. Both effects were blocked by intracellular caesium. In contrast, intracellular caesium failed to affect WIN 55,212-2-mediated synaptic inhibition. The WIN 55,212-2-mediated synaptic inhibition was blocked by the Gi/o protein inhibitor pertussis toxin (PTX), but not by the GABA(A) receptor antagonist bicuculline or GABA(B) receptor antagonist SCH 50911. Pretreatment with the N-type Ca2+ channel antagonist [omega]-conotoxin GVIA selectively abolished the WIN-55,212-2-mediated synaptic inhibition. These results suggest that cannabinoids depress the corticostriatal glutamatergic synaptic transmission through the activation of presynaptic CB1 receptors to inhibit N-type Ca2+ channel activity, which in turn reduces glutamate release. The presynaptic action of cannabinoids is mediated by a PTX-sensitive Gi/o protein-coupled signalling pathway.

Cortical renal leiomyoma with extension to renal pelvis.

We describe a case of renal leiomyoma in a 21-year-old woman who presented with flank pain and hematuria. Urographic and computed tomographic (CT) studies revealed a large right renal mass with polypoid outgrowth protruding into the renal pelvis. Cortical renal leiomyoma with this radiographic manifestation is extremely rare.