Phytoplasmas (genus ‘
Candidatus
Phytoplasma’) are plant pathogenic bacteria that reside intracellularly within the plant phloem. They infect hundreds of plant species worldwide and induce a wide ...range of symptoms, including stunting, yellowing, witches’ broom, phyllody, virescence, proliferation, and purple top. The phytoplasma genome has unique features that overturn commonly known wisdom. For example, ATP synthase, which is thought to be essential for life, is not encoded, which provides opportunities for reconsidering the question "what is life?" Phytoplasmas cause dramatic changes in plant development and parasitizes not only plants but also vector insects by host switching. Therefore, the molecular mechanisms of how phytoplasmas manipulate host plants and how they infect different hosts are of particular interest. This review summarizes the history of phytoplasma discovery, unique survival strategies revealed by genome sequencing, and the molecular mechanisms by which phytoplasmas manipulate host plants.
Catalytic steam reforming of methane for hydrogen production proceeds even at 473 K over 1 wt% Pd/CeO
catalyst in an electric field, thanks to the surface protonics. Kinetic analyses demonstrated the ...synergetic effect between catalytic reaction and electric field, revealing strengthened water pressure dependence of the reaction rate when applying an electric field, with one-third the apparent activation energy at the lower reaction temperature range. Operando-IR measurements revealed that proton conduction via adsorbed water on the catalyst surface occurred during electric field application. Methane was activated by proton collision at the Pd-CeO
interface, based on the inverse kinetic isotope effect. Proton conduction on the catalyst surface plays an important role in methane activation at low temperature. This report is the first describing promotion of the catalytic reaction by surface protonics.
In this retrospective analysis using the Transplant Registry Unified Management Program, we identified 145 patients with human herpesvirus (HHV)-6 encephalitis among 6593 recipients. The cumulative ...incidences of HHV-6 encephalitis at 100 days after transplantation in all patients, recipients of bone marrow or PBSCs and recipients of cord blood were 2.3%, 1.6% and 5.0%, respectively. Risk factors identified in multivariate analysis were male sex, type of transplanted cells (relative risk in cord blood transplantation, 11.09, P<0.001; relative risk in transplantation from HLA-mismatched unrelated donor, 9.48, P<0.001; vs transplantation from HLA-matched related donor) and GvHD prophylaxis by calcineurin inhibitor alone. At 100 days after transplantation, the overall survival rate was 58.3% and 80.5% among patients with and without HHV-6 encephalitis, respectively (P<0.001). Neuropsychological sequelae remained in 57% of 121 evaluated patients. With both foscarnet and ganciclovir, full-dose therapy (foscarnet ⩾180 mg/kg, ganciclovir ⩾10 mg/kg) was associated with better response rate (foscarnet, 93% vs 74%, P=0.044; ganciclovir, 84% vs 58%, P=0.047). HHV-6 encephalitis is not rare not only in cord blood transplant recipients but also in recipients of HLA-mismatched unrelated donors. In this study, development of HHV-6 encephalitis was associated with a poor survival rate, and neurological sequelae remained in many patients.
Probiotics are live microorganisms that potentially confer beneficial outcomes to host by modulating gut microbiota in the intestine. The aim of this study was to comprehensively investigate effects ...of probiotics on human intestinal microbiota using 454 pyrosequencing of bacterial 16S ribosomal RNA genes with an improved quantitative accuracy for evaluation of the bacterial composition. We obtained 158 faecal samples from 18 healthy adult Japanese who were subjected to intervention with 6 commercially available probiotics containing either Bifidobacterium or Lactobacillus strains. We then analysed and compared bacterial composition of the faecal samples collected before, during, and after probiotic intervention by Operational taxonomic units (OTUs) and UniFrac distances. The results showed no significant changes in the overall structure of gut microbiota in the samples with and without probiotic administration regardless of groups and types of the probiotics used. We noticed that 32 OTUs (2.7% of all analysed OTUs) assigned to the indigenous species showed a significant increase or decrease of ≥10-fold or a quantity difference in >150 reads on probiotic administration. Such OTUs were found to be individual specific and tend to be unevenly distributed in the subjects. These data, thus, suggest robustness of the gut microbiota composition in healthy adults on probiotic administration.
Stenotrophomonas maltophilia is a pathogen commonly associated with respiratory infection. However, the characteristics of pneumonia caused by S. maltophilia remain unknown.
To evaluate the ...characteristics of and risk factors for S. maltophilia pneumonia.
A retrospective evaluation was undertaken of 2002 patients with sputum cultures positive for S. maltophilia between January 2010 and December 2019. Cases were excluded based on clinical information and laboratory results. Included cases were divided into two groups: the S. maltophilia pneumonia group (patients with pneumonia caused by S. maltophilia) and the non-S. maltophilia pneumonia group (patients with pneumonia caused by pathogens other than S. maltophilia). Patient characteristics, clinical data and Sequential Organ Failure Assessment (SOFA) scores were compared between the groups.
Eight and 91 patients were assigned to the S. maltophilia pneumonia and non-S. maltophilia pneumonia groups, respectively. The median age was significantly lower in the S. maltophilia pneumonia group than in the non-S. maltophilia pneumonia group (63.4 vs 73.1 years; P<0.01), and the SOFA score was significantly higher in the S. maltophilia pneumonia group (7.5 vs 3.0; P<0.01). Underlying malignancy and pre-administration of antipseudomonal β-lactams and steroids were confirmed in seven of the eight cases in the S. maltophilia pneumonia group, suggesting an association with immunosuppression.
Pneumonia due to S. maltophilia is a rare occurrence. Treatment for this pathogen should be considered in cases of pneumonia with: (1) predominance of S. maltophilia in sputum cultures; (2) pre-administration of broad-spectrum antibiotics; (3) immunodeficiency; and (4) a high SOFA score.
The proto-oncogene BMI1 and its product, Bmi1, is overexpressed in various types of tumors, particularly in aggressive tumors and tumors resistant to conventional chemotherapy. BMI1/Bmi1 is also ...crucially involved in cancer-initiating cell maintenance, and is recurrently upregulated in mantle cell lymphoma (MCL), especially aggressive variants. Recently, side population (SP) cells were shown to exhibit tumor-initiating characteristics in various types of tumors. In this study, we show that recurrent MCL cases significantly exhibit upregulation of BMI1/Bmi1. We further demonstrate that clonogenic MCL SP shows such tumor-initiating characteristics as high tumorigenicity and self-renewal capability, and that BMI1 was upregulated in the SP from recurrent MCL cases and MCL cell lines. On screening for upstream regulators of BMI1, we found that expression of microRNA-16 (miR-16) was downregulated in MCL SP cells by regulating Bmi1 in the SPs, leading to reductions in tumor size following lymphoma xenografts. Moreover, to investigate downstream targets of BMI1 in MCL, we performed cross-linking/chromatin immunoprecipitation assay against MCL cell lines and demonstrated that Bmi1 directly regulated pro-apoptotic genes such as BCL2L11/Bim and PMAIP1/Noxa, leading to enhance anti-apoptotic potential of MCL. Finally, we found that a proteasome inhibitor bortezomib, which has been recently used for relapsed MCL, effectively induced apoptosis among MCL cells while reducing expression of Bmi1 and increasing miR-16 in MCL SP. These results suggest that upregulation of BMI1 and downregulation of miR-16 in MCL SP has a key role in the disease's progression by reducing MCL cell apoptosis. Our results provide important new insight into the pathogenesis of MCL and strongly suggest that targeting BMI1/Bmi1 might be an effective approach to treating MCL, particularly refractory and recurrent cases.
Reduced gray matter volumes in the superior temporal gyrus (STG) have been reported in patients with schizophrenia. Such volumetric abnormalities might denote alterations in cortical thickness, ...surface area, local gyrification or all of these factors. The STG can be anatomically divided into five subregions using automatic parcellation in FreeSurfer: lateral aspect of the STG, anterior transverse temporal gyrus of Heschl gyrus (HG), planum polare (PP) of the STG, planum temporale (PT) of the STG and transverse temporal sulcus.
We acquired magnetic resonance imaging (MRI) 3T scans from 40 age- and sex-matched patients with schizophrenia and 40 healthy subjects, and the scans were automatically processed using FreeSurfer. General linear models were used to assess group differences in regional volumes and detailed thickness, surface area and local gyrification.
As expected, patients with schizophrenia had significantly smaller bilateral STG volumes than healthy subjects. Of the five subregions in the STG, patients with schizophrenia showed significantly and marginally reduced volumes in the lateral aspect of the STG and PT of the STG bilaterally compared with healthy subjects. The volumetric alteration in bilateral lateral STG was derived from both the cortical thickness and surface area but not local gyrification. There was no significant laterality of the alteration in the lateral STG between patients and controls and no correlation among the structures and clinical characteristics.
These findings suggest that of five anatomical subregions in the STG, the lateral STG is one of the most meaningful regions for brain pathophysiology in schizophrenia.
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