Image_1_Global trends in research of pseudomyxoma peritonei: a bibliometric and visualization analysis.pdf

ObjectivePseudomyxoma peritonei (PMP) was a complex disease that had attracted increasing attention. However, there had been no bibliometric analysis of this disease so far. This study aimed to explore the current situation and frontier trend of PMP through bibliometric and visualization analysis, and to indicate new directions for future research.MethodsThe original research articles and reviews related to the PMP research were downloaded from Web of Science Core Collection on September 11, 2023. CiteSpace (6.2.R4) and VOSviewer(1.6.18) were used to perform bibliometric analysis of the publications, and establish the knowledge map. The data collected was analyzed using the Online Analysis Platform of Bibliometric to evaluate the cooperation of countries in this field.ResultsWe identified 1449 original articles and reviews on PMP published between 1998 and 2023. The number of publications on PMP increased continuously. The United States, the United Kingdom and China were the top contributors. The most productive organization was the MedStar Washington Hospital Center. Sugarbaker, Paul H. was the most prolific author and the most cited. Keyword analysis showed that “Pseudomyxoma peritonei”, “cancer”, “cytoreductive surgery”, and “hyperthermic intraperitoneal chemotherapy” were the most common keywords. The earliest and latest used keywords were “mucinous tumors” and “impact”, respectively. “classification”, “cytoreductive surgery”, “appendiceal” were the top 3 strongest citation bursts. The reference “Carr NJ, 2016, AM J SURG PATHOL” had the highest co-citations.ConclusionThis bibliometric analysis showed an increasing trend in literature related to PMP. The research trends and hotspots identified in this study could guide the future research directions in this field, in order to promote the development of PMP.</p

Table_1_Global trends in research of pseudomyxoma peritonei: a bibliometric and visualization analysis.docx

ObjectivePseudomyxoma peritonei (PMP) was a complex disease that had attracted increasing attention. However, there had been no bibliometric analysis of this disease so far. This study aimed to explore the current situation and frontier trend of PMP through bibliometric and visualization analysis, and to indicate new directions for future research.MethodsThe original research articles and reviews related to the PMP research were downloaded from Web of Science Core Collection on September 11, 2023. CiteSpace (6.2.R4) and VOSviewer(1.6.18) were used to perform bibliometric analysis of the publications, and establish the knowledge map. The data collected was analyzed using the Online Analysis Platform of Bibliometric to evaluate the cooperation of countries in this field.ResultsWe identified 1449 original articles and reviews on PMP published between 1998 and 2023. The number of publications on PMP increased continuously. The United States, the United Kingdom and China were the top contributors. The most productive organization was the MedStar Washington Hospital Center. Sugarbaker, Paul H. was the most prolific author and the most cited. Keyword analysis showed that “Pseudomyxoma peritonei”, “cancer”, “cytoreductive surgery”, and “hyperthermic intraperitoneal chemotherapy” were the most common keywords. The earliest and latest used keywords were “mucinous tumors” and “impact”, respectively. “classification”, “cytoreductive surgery”, “appendiceal” were the top 3 strongest citation bursts. The reference “Carr NJ, 2016, AM J SURG PATHOL” had the highest co-citations.ConclusionThis bibliometric analysis showed an increasing trend in literature related to PMP. The research trends and hotspots identified in this study could guide the future research directions in this field, in order to promote the development of PMP.</p

Reversible Interfacial Charge Transfer and Delayed Emission in InP/ZnSe/ZnS Quantum Dots with Hexadecanethiol

The results in this paper show that holes are rapidly and reversibly transferred from red-emitting InP/ZnSe/ZnS quantum dots (QDs) to adsorbed hexadecanethiol (HDT) forming an equilibrium between the thiols and the QD valence band. Photoexcitation results in populations of holes in the valence band and in slightly higher-energy shell-localized traps. Trap to valence band hole tunneling results in a photoluminescence risetime having time constants varying from 300 ps to 2 ns. The presence of adsorbed HDT eliminates the slower risetime component, indicating that hole transfer from the shell-localized traps that are closest to the particle surface efficiently competes with tunneling to the QD core. This shows that the interfacial charge transfer equilibrium is established in less than 2 ns. The population of the shell-localized traps corresponds to a reservoir of hole states that eventually tunnel to the core-localized valence band, resulting in delayed emission. The amount of delayed emission increases rapidly with ZnSe shell thickness and is slightly blue-shifted from the prompt photoluminescence. We propose an energetic model in which the HDT/valence band equilibrium is affected by the extent of valence band quantum confinement and an electric field produced by core–shell interfacial dipoles. This model explains the core size, shell thickness, and photoluminescence (PL) wavelength dependence of this equilibrium

RpoS represses EsrB expression and colonization during infection of the fish.

(A-B)In vivo measurement of T3SS (eseB), T6SS (evpA) and rpoS gene expression using luminescence. The WT, ΔrpoS, and rpoSR99A strains harboring PeseB-, PevpA-, or PrpoS- luc reporter plasmids were inoculated into turbot and luminescence and bacterial burden was measured 8 dpi. The P values are based on the ANOVA analysis of the relative fluorescence units (RFU) and the bacterial burden in each fish (n = 3). (C) In vivo competition assays for the ΔrpoS, ΔesrB, rpoSOE, and rpoSR99A strains vs the WT or WTΔp (WT with pEIB202 cured), which are Cm resistant or sensitive, respectively. The strains rpoSOE::Plac-esrB (rpoSOE constitutively expressing esrB driven by Plac), ΔesrB/PesrBmut1-esrB,ΔesrB/PesrBmut2-esrB, and ΔesrB/PesrBmut3-esrB (ΔesrB harboring plasmid pUTat expressing esrB driven by PesrBmut1, PesrBmut2, or PesrBmut3) were competed vs the WT. 1:1 mixtures of the indicated strains were i.p. administered into turbot and cultivated for 8 dpi before CFU in the liver were enumerated. *P P P(D) Competitive indices of the indicated strains mixed with WT or WTΔp inoculated into fish and recovered at 1, 2, 5, 8, 11 and 14 dpi were performed as described in C (n = 5 per group).</p

Identification of factors regulating the expression of the response regulator EsrB with a transposon insertion sequencing (Tn-seq) screen.

(A) Schematic of Tn-seq strategy used for finding putative esrB regulators. A transposon library was created in a strain harboring a PesrB-Kan fusion (inserted in a neutral position on the chromosome), which yields Kan resistance when the esrB promoter is active. The library was grown in DMEM conditions, which induces the esrB promoter, in either the absence or presence of Kan. The sites and abundance of transposon insertions under the two conditions were compared. (B) Volcano plot showing the output/input fold change (FC) in reads of genes as revealed by Tn-seq analysis. The genes of interest were highlighted with cut-off of log2 FC > 1 or FC P value (C-D) Artemis plots of the abundance of reads in rpoS (D) and lon (E) in DMEM (red) versus DMEM-Kan (green) medium. The height of the red and green bars correlates with the number of reads.</p

RpoS represses EsrB and T3/T6SS expression.

(A) Relative fluorescence units (RFU) of the WT, ΔrpoS and rpoS+ strains grown in DMEM medium at 3, 9, 12 h after inoculation. The results are shown as the mean ± S.D. (n = 3). ***, P P t-test. Western blot of RpoS abundance in indicated strains at 9 h is shown on top; DnaK abundance was used as a loading control. The numbers correspond to densitometry measurements. (B) Extracellular protein profiles of WT, ΔesrB, ΔrpoS, rpoSOE(rpoS over-expression), ΔesrB rpoSOE, and rpoSOE:: Plac-esrB (rpoSOE strain harboring constitutively expressing esrB driven from Plac) were separated on SDS-PAGE gels, and specific bands corresponding to T3SS and T6SS proteins [10, 14] are shown. (C) Autoaggregation of the indicated strains statically cultured in DMEM, at 28°C for 24 h. The concentrated supernatants from the same amount of cells were blotted with anti EseB specific antiserum. DnaK was used as the loading control for the blots. (D) MA plots showing differences in the transcriptomes of WT and ΔrpoS cultured in DMEM (n = 3). T3SS, T6SS and iron uptake related genes are highlighted. (E) qRT-PCR assays for the indicated transcripts. The results shown are mean ± S.D. (n = 3). gyrB was used as the internal control.</p

Identification of RpoS R99 as a critical residue for the repression of the expression of <i>esrB</i> and other genes.

(A) Structural model of RpoS interacting with the discriminator sequence based on alignment with of σA (5VI5, Chain F [44]). (B) Fluorescence expressed by PesrB-luxAB in the indicated strain backgrounds. The intracellular RpoS levels of the indicated strains were detected with western blot assays, and DnaK was used as a loading control. The results shown are the mean ± S.D. (n = 3). ***, P P >0.05) based on student’s t-test. (C) In vitro transcription reactions using a PesrB, PesrB mut1 or PesrB mut2 templates, NTPs, and E. coli RNAP core enzyme as well as E. piscicida RpoSR99A and RpoD. Transcripts from the reactions were purified, reverse-transcribed (RT, +) and detected using PCR. As a control, the same purified transcripts were treated using the same process but without addition of reverse transcriptase (RT, -). (D) RpoSR99A does not repress production of T3/T6SS proteins. (E) Growth of indicated strains in increasing concentration of H2O2. WT, ΔrpoS, rpoSOE, and rpoSR99A were inoculated into DMEM containing various concentrations of H2O2 and statically grown for 24 h at which point OD600 was measured; MICs are shown. (F) Capacity of the RpoSR99A mutant to repress or activate genes in the RpoS regulon compared to WT; qRT-PCR analyses with gyrB as the internal control. The results shown are the mean ± S.D. (n = 3).</p

The -6G in the discriminator sequence of RpoS controlled promoters is required for RpoS to act as a repressor.

(A) Venn diagram showing genes directly bound and regulated by RpoS as revealed by RNA-seq and ChIP-seq analysis. (B) RpoS binding motifs on activated and repressed genes. (C) A promoterless luxAB reporter was fused to WT and mutant PesrB (left panel), cloned into plasmid pUTat and introduced into the WT strain. The fluorescence of the respective strains was assayed at 9 h (right panel). *** P P >0.05) based on student’s t-test.</p

RpoS interacts with the <i>esrB</i> promoter region and inhibits <i>esrB</i> transcription <i>in vitro</i>.

(A) Pull-down of RpoS by the promoter region of esrB (PesrB). DNA fragments containing PesrB or the esrB open reading frame (esrB orf) were labeled with biotin and fixed to agarose beads. The probe-labeled beads were then mixed with excess Poly (dI:dC) and lysates from ΔrpoS cells over-expressing Flag-tagged RpoS (ΔrpoS/flag-rpoS), washed, and eluted with a concentration gradient of NaCl and ultimately treated with ddH2O at 70°C to release bound proteins, followed by western blot analysis with an anti-Flag-specific monoclonal antibody. (B) ChIP assay analysis of RpoS binding to PesrB in vivo. Stationary phase cells were cross-linked, washed, and sonicated to produce sheared chromosomal DNA. DNA was purified from the sheared pellets both before precipitation (input) and after precipitation in the presence (+) and absence (-) of the anti Flag antibody (IP). PCR was then used to amplify PesrB. (C) Normalized strand-specific-RNA-seq reads of esrB transcripts in ΔrpoS vs WT were used to identify the +1 site of the esrB transcript (depicted with an arrow). (D) In vitro transcription reactions using templates containing PesrB, PesrB mut1 or PesrB mut2, NTPs, and E. coli RNAP core enzyme as well as E. piscicida RpoS and/or RpoD. Transcripts from the reactions were purified, reverse-transcribed (RT, +) and detected using PCR. As a control, the same purified transcripts were treated using the same process but without addition of reverse transcriptase (RT, -). (E) Schematic of two engineered variants of the esrB promoter; PesrB mut1 contains substitutions in the -10 box and PesrB mut2 contains substitutions in the neighboring discriminator GCC sequence. (F) Fluorescence values from WT, ΔrpoS, and rpoSOE strains with chromosomal luxAB reporter driven by PesrB, PesrB mut1 or PesrB mut2. *** P P >0.05) based on student’s t-test.</p

RpoS is regulated by Lon and mediates control of <i>esrB</i> expression in response to environmental stresses.

(A) Western blot analysis of RpoS and Lon (top) and expression of PesrB-luxAB in WT and lonOE (Lon over-expression) strains. The results shown are mean ± S.D. (n = 3). ***, P t-test. (B) Extracellular protein profiles of WT, lonOE, ΔrpoS, and ΔrpoS lonOE were separated on SDS-PAGE gels and specific bands corresponding to T3/T6SS proteins are shown. (C) Relative transcript levels of esrB, eseB, and evpC in lonOE vs WT strains (qRT-PCR assays with normalization to gyrB transcript, mean ± S.D. (n = 3). (D) Western blot analysis of RpoS and expression of the esrB promoter in WT and ΔrpoS strains grown in DMEM supplemented with low (1 mg/ml) or high concentrations (4.5 mg/ml) of glucose, with (+) or without (-) addition of H2O2, and at 22°C or 28°C. DnaK was used as the loading control for the blots. The results shown are mean ± S.D. (n = 3). ***, P t-test.</p