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Pandoraea fibrosis sp. nov., a novel Pandoraea species isolated from clinical respiratory samples

See-Too WS, Ambrose M, Malley R, Ee R, Mulcahy E, Manche E, et al.

Int J Syst Evol Microbiol, 2019 Mar;69(3):645-651.
PMID: 30676309 DOI: 10.1099/ijsem.0.003147

Pandoraea species have been isolated from diverse environmental samples and are emerging important respiratory pathogens, particularly in people with cystic fibrosis (CF). In the present study, two bacterial isolates initially recovered from consecutive sputum samples collected from a CF patient and identified as Pandoraea pnomenusa underwent a polyphasic taxonomic analysis. The isolates were found to be Gram-negative, facultative anaerobic motile bacilli and subsequently designated as strains 6399T (=LMG29626T=DSM103228T) and 7641 (=LMG29627=DSM103229), respectively. Phylogenetic analysis based on 16S rRNA and gyrB gene sequences revealed that 6399T and 7641 formed a distinct phylogenetic lineage within the genus Pandoraea. Genome sequence comparison analysis indicated that strains 6399T and 7641 are clonal and share 100 % similarity, however, similarity to other type strains (ANIb 73.2-88.8 %, ANIm 83.5-89.9 % and OrthoANI 83.2-89.3 %) indicates that 6399T and 7641 do not belong to any of the reported type species. The major cellular fatty acids of 6399T were C16 : 0 (32.1 %) C17 : 0cyclo (18.7 %) and C18 : 1ω7c (14.5 %), while Q-8 was the only respiratory quinone detected. The major polar lipids identified were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content of 6399T was 62.9 (mol%). Strain 6399T can be differentiated from other members of Pandoraea by the absence of C19 : 0ω8c cyclo and by the presence of C17 : 0ω8c cyclo. Together our data show that the bacterial strains 6399T and 7641 represent a novel species of the genus Pandoraea, for which the name Pandoraea fibrosis sp. nov. is proposed (type strain 6399T).
Energy Band Gap Modulation in Nd-Doped BiFeO3/SrRuO3 Heteroepitaxy for Visible Light Photoelectrochemical Activity

Tan KH, Chen YW, Van CN, Wang H, Chen JW, Lim FS, et al.

ACS Appl Mater Interfaces, 2019 Jan 09;11(1):1655-1664.
PMID: 30561192 DOI: 10.1021/acsami.8b17758

The ability of band offsets at multiferroic/metal and multiferroic/electrolyte interfaces in controlling charge transfer and thus altering the photoactivity performance has sparked significant attention in solar energy conversion applications. Here, we demonstrate that the band offsets of the two interfaces play the key role in determining charge transport direction in a downward self-polarized BFO film. Electrons tend to move to BFO/electrolyte interface for water reduction. Our experimental and first-principle calculations reveal that the presence of neodymium (Nd) dopants in BFO enhances the photoelectrochemical performance by reduction of the local electron-hole pair recombination sites and modulation of the band gap to improve the visible light absorption. This opens a promising route to the heterostructure design by modulating the band gap to promote efficient charge transfer.
Combined chemotherapy and EUS-guided intra-tumoral 32-P implantation for locally advanced pancreatic ductal adenocarcinoma: a pilot study

Naidu J, Bartholomeusz D, Zobel J, Safaeian R, Hsieh W, Crouch B, et al.

Endoscopy, 2021 Jan 13.
PMID: 33440437 DOI: 10.1055/a-1353-0941

AIM: This study evaluated clinical outcomes of combined chemotherapy and Endoscopic Ultrasound (EUS) guided intra-tumoral radioactive phosphorus-32 (32P OncoSil) implantation in locally advanced pancreatic adenocarcinoma (LAPC).
METHODS: Consecutive patients with a new histological diagnosis of LAPC were recruited over 20 months. Baseline CT and 18FDG PET-CT were performed and repeated after 12 weeks to assess response to treatment. Following 2 cycles of conventional chemotherapy, patients underwent EUS-guided 32P OncoSil implantation followed by a further six cycles of chemotherapy.
RESULTS: Twelve patients with LAPC (8M:4F; median age 69 years, IQR 61.5-73.3) completed the treatment. Technical success was 100% and no procedural complications were reported. At 12 weeks, there was a median reduction of 8.2cm3 (95% CI 4.95-10.85; p=0.003) in tumour volume, with minimal or no 18FDG uptake in 9 (75%) patients. Tumour downstaging was achieved in 6 (50%) patients, leading to successful resection in 5 (42%) patients, of which 4 patients (80%) had clear (R0) resection margins.
CONCLUSIONS: EUS guided 32P OncoSil implantation is feasible and well tolerated and was associated with a 42% rate of surgical resection in our cohort. However, further evaluation in a larger randomized multicenter trial is warranted. (32P funded by OncoSil Medical Ltd, equipment and staff funded by the Royal Adelaide Hospital, ClinicalTrials.gov number, NCT03003078).
Fulltext Phenotypic and genomic survey on organic acid utilization profile of Pseudomonas mendocina strain S5.2, a vineyard soil isolate

Chong TM, Chen JW, See-Too WS, Yu CY, Ang GY, Lim YL, et al.

AMB Express, 2017 Dec;7(1):138.
PMID: 28655216 DOI: 10.1186/s13568-017-0437-7

Root exudates are chemical compounds that are released from living plant roots and provide significant energy, carbon, nitrogen and phosphorus sources for microbes inhabiting the rhizosphere. The exudates shape the microflora associated with the plant, as well as influences the plant health and productivity. Therefore, a better understanding of the trophic link that is established between the plant and the associated bacteria is necessary. In this study, a comprehensive survey on the utilization of grapevine and rootstock related organic acids were conducted on a vineyard soil isolate which is Pseudomonas mendocina strain S5.2. Phenotype microarray analysis has demonstrated that this strain can utilize several organic acids including lactic acid, succinic acid, malic acid, citric acid and fumaric acid as sole growth substrates. Complete genome analysis using single molecule real-time technology revealed that the genome consists of a 5,120,146 bp circular chromosome and a 252,328 bp megaplasmid. A series of genetic determinants associated with the carbon utilization signature of the strain were subsequently identified in the chromosome. Of note, the coexistence of genes encoding several iron-sulfur cluster independent isoenzymes in the genome indicated the importance of these enzymes in the events of iron deficiency. Synteny and comparative analysis have also unraveled the unique features of D-lactate dehydrogenase of strain S5.2 in the study. Collective information of this work has provided insights on the metabolic role of this strain in vineyard soil rhizosphere.
Tunable photoelectrochemical performance of Au/BiFeO3 heterostructure

Huang YL, Chang WS, Van CN, Liu HJ, Tsai KA, Chen JW, et al.

Nanoscale, 2016 Aug 25;8(34):15795-801.
PMID: 27533610 DOI: 10.1039/c6nr04997d

Ferroelectric photoelectrodes, other than conventional semiconductors, are alternative photo-absorbers in the process of water splitting. However, the capture of photons and efficient transfer of photo-excited carriers remain as two critical issues in ferroelectric photoelectrodes. In this work, we overcome the aforementioned issues by decorating the ferroelectric BiFeO3 (BFO) surface with Au nanocrystals, and thus improving the photoelectrochemical (PEC) performance of BFO film. We demonstrate that the internal field induced by the spontaneous polarization of BFO can (1) tune the efficiency of the photo-excited carriers' separation and charge transfer characteristics in bare BFO photoelectrodes, and (2) modulate an extra optical absorption within the visible light region, created by the surface plasmon resonance excitation of Au nanocrystals to capture more photons in the Au/BFO heterostructure. This study provides key insights for understanding the tunable features of PEC performance, composed of the heterostructure of noble metals and ferroelectric materials.
Insights into the diversity of blood donation practice across Asia: How blood collection agencies adapt donor criteria and processes to their population

Fung YL, Alcantara RM, Cavalli LB, Chen JW, Chen YY, Donkin R, et al.

Vox Sang, 2023 Sep 27.
PMID: 37753662 DOI: 10.1111/vox.13530

BACKGROUND AND OBJECTIVES: Securing an adequate blood supply relies on accurate knowledge of blood donors and donation practices. As published evidence on Asian populations is sparse, this study aims to gather up-to-date information on blood donors and donation practices in Asia to assist planning and strategy development.
MATERIALS AND METHODS: Ten blood collection agencies (BCAs) provided 12 months' data on donors who met eligibility criteria or were deferred, as well as details of their donation practices. Body mass index and blood volumes were calculated and analysed.
RESULTS: Data on 9,599,613 donations and 154,834 deferrals from six national and four regional BCAs revealed varied donation eligibility and collection practices. Seven used haemoglobin (Hb) criteria below the World Health Organization anaemia threshold. Seven accepted donors weighing <50 kg. Data collection on the weight and height of donors and on deferrals was inconsistent, often not routine. Deferred donors appear to weigh less, with corresponding lower estimated blood volume.
CONCLUSION: The diversity in eligibility criteria and donation practices reflects each BCA's strategy for balancing donor health with securing an adequate blood supply. Use of lower Hb criteria substantiate their appropriateness in Asia and indicate the need to define Hb reference intervals relevant to each population. We encourage routine gathering of donor weight and height data to enable blood volume estimation and local optimization of donation volumes. Blood volume estimation formulae specific for the Asian phenotype is needed. Information from this study would be useful for tailoring donation criteria of Asian donors around the world.
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.

Autophagy, 2016;12(1):1-222.
PMID: 26799652 DOI: 10.1080/15548627.2015.1100356