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Background: Marginal zone lymphomas of mucosa-associated lymphatic tissues (MZL of MALT) are a group of indolent B-cell neoplasms, which are thought to arise from chronic antigenic stimulation of B-cells either due to underlying chronic infection or autoimmune disease. Little is known about potential causative pathogens in pulmonary MZL (PMZL), although some data suggests a potential role of Achromobacter (A.) xylosoxidans. Methods: An index case of chronic pulmonary colonisation with Tropheryma (T.) whipplei and subsequent development of PMZL was identified by T. whipplei specific PCR and metagenomic next genome sequencing (mNGS). This case prompted a retrospectively conducted analysis of T. whipplei-specific PCRs in lung tissue from PMZL patients (n = 22), other pulmonary lymphomas, and normal controls. Positive results were confirmed by mNGS. A systematic search for T. whipplei and A. xylosoxidans in our in-house mNGS dataset comprising autopsy lungs, lung biopsies and lung resection specimens (n = 181) was subsequently performed. Results: A 69-year-old patient presented with weight loss and persistent pulmonary consolidation. Subsequent mNGS analysis detected T. whipplei in the resected lung specimen. An antibiotic regimen eventually eliminated the bacterium. However, the consolidation persisted, and the diagnosis of PMZL was made in a second lung resection specimen. A second case of T. whipplei-associated PMZL was subsequently detected in the retrospectively analysed PMZL cohort. Both cases showed comparatively few mutations and no mutations in genes encoding for NF-κB pathway components, suggesting that T. whipplei infection may substitute for mutations in these PMZL. None of the samples in our in-house dataset tested positive for T. whipplei. In contrast, A. xylosoxidans was frequently found in both autopsy lungs and lung biopsy / resection specimens that were not affected by PMZL (> 50%). Conclusions: Our data suggests that T. whipplei colonisation of lungs may trigger PMZL as a potential driver. Systematic analyses with larger cohorts should be conducted to further support this hypothesis. The frequent detection of A. xylosoxidans in lung tissue suggests that it is a common component of the pulmonary microbiome and therefore less likely to trigger lymphomas. [ABSTRACT FROM AUTHOR]

Background: Angiotensin-converting enzyme II or ACE2 is an integral membrane protein present on many types of cells, including vascular endothelial cells and lung alveolar epithelial cells. This receptor serves as the entry point for SARS-coronaviruses (SARS-CoVs), including a novel coronavirus 2019-nCoV. Limited availability of these receptors can thwart cellular entry of this virus. Methods: We tested the effects of ascorbic acid (vitamin C) on cellular expression of ACE2 at the protein and RNA levels in human small alveolar epithelial cells and microvascular endothelial cells. In addition, we investigated whether combinations of ascorbic acid with other natural compounds can affect ACE2 expression. Results: The results show that ascorbic acid itself has moderate but consistent lowering effects on ACE2 expression at the cellular, protein, and RNA levels. Some natural compounds were effective in lowering ACE2 cellular expression, with the highest inhibitory effects observed for baicalin (75%) and theaflavin (50%). Significantly, combinations of these and other test compounds with ascorbic acid further decreased ACE2 expression. The highest impact of ascorbate on ACE2 expression was noted when combined with theaflavin (decrease from 50% to 87%), zinc (decrease from 22% to 62%), and with 10-undecenoic acid (from 18% to 53%). Ascorbic acid showed moderate additional benefits in decreasing ACE2 expression when combined with N-acetylcysteine and baicalin. Conclusion: Our study provides valuable experimental confirmation of the efficacy of micronutrients in controlling ACE2 expression—the coronavirus cellular "entry" point. It further validates the importance of nutrient interactions in various aspects of cellular metabolism and in considering potential therapeutic applications of nutrient-based approaches. The study shows that ascorbic acid and its combination with some natural compounds could be included in developing preventive and therapeutic approaches toward the current pandemic. [ABSTRACT FROM AUTHOR]

Gene expression analysis of peripheral blood cells may provide valuable information about the triggered molecular processes in systemic lupus erythematosus (SLE). The study aimed to quantify the mRNA in peripheral blood of seven target genes, including inflammatory cytokine genes (IL23A, IL12B, TNFA, IL18), and T regulatory-related genes (FOXP3, TGFB1, IL10) in patients with SLE and to correlate expression levels with disease activity and/or clinical manifestations. The relative quantification of target genes was performed using real-time polymerase chain reaction in peripheral blood obtained from 28 adult SLE females and 17 healthy women. The highest up-regulation in the blood of SLE patients was observed for IL23A with a median 9.54 (p < 0.0001), followed by TGFB1 (median: 2.07; p = 0.047) and IL10 (median: 1.84; p = 0.013). IL12B and TNFA were significantly down-regulated in patients compared to controls (median: 0.521; p = 0.0023, and median: 0.519; p = 0.0003, respectively). FOXP3 mRNA was lower among patients with higher degree of disease activity (median: 0.338; p = 0.029) and showed inverse correlation with Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). IL18 mRNA correlated positively with the SLEDAI and was highly expressed during severe flares (median: 1.216; p = 0.021). IL18 up-regulation was associated with anti-dsDNA antibody positivity, while FOXP3 down-regulation with lupus nephritis. Our study pointed out the relationship of SLE disease activity and particular clinical manifestations with IL18 and FOXP3 expression, and the significant contribution of IL23A in the SLE immunopathogenesis. Hence, the peripheral blood cytokine mRNAs should be exploited as novel prognostic and diagnostic biomarkers. [ABSTRACT FROM AUTHOR]

Abstract: Retinal bipolar cells and ganglion cells are known to possess voltage-gated T-type Ca2+ channels. Previous electrophysiological recording studies suggested that there is differential expression of different T-type Ca2+ channel α1 subunits among bipolar cells. The detailed expression patterns of the individual T-type Ca2+ channel subunits in the retina, however, remain unknown. In this study, we examined the expression of the CaV3.2 Ca2+ channel α1 subunit in the mouse retina using immunohistochemical analysis and patch-clamp recordings together with a CaV3.2 knock out (KO) mouse line. The specificity of a CaV3.2 Ca2+ channel antibody was first confirmed in recombinant T-type Ca2+ channels expressed in human embryonic kidney (HEK) cells and in CaV3.2 KO mice. Our immunohistochemical analysis indicates that the CaV3.2 antibody labels a subgroup of type-3 cone bipolar cells (CBCs), the PKAβII-immunopositive type-3 CBCs. The labeling was observed throughout the cell including dendrites and axon terminals. Our patch-clamp recording results further demonstrate that CaV3.2 Ca2+ channels contribute to the T-type Ca2+ current in a subpopulation of type-3 CBCs. The findings of this study provide new insights into understanding the functional roles of T-type Ca2+ channels in retinal processing. [Copyright &y& Elsevier]

Parkinson's disease (PD) is the second most common progressive neurodegenerative disorder characterized by the degeneration of dopaminergic neurons. Detecting changes in gene expression in untreated de novo patients with PD is important for understanding the disease pathogenesis and for identifying biomarkers of the preclinical stage of PD. In this study, the expression of the glycogen synthase kinase-3 beta gene ( GSK3B) was investigated in the peripheral blood of several groups of neurological patients using reverse transcription reaction and real-time PCR. Our results suggest that the GSK3B expression level cannot serve as a biomarker for early stages of PD. [ABSTRACT FROM AUTHOR]

RNA differential display (DD) is a powerful and straightforward method that employs random reverse-transcription polymerase chain reaction amplification of mRNA species with electrophoresis for comparative analysis of two or more transcriptomes. The small yeast genome represents a convenient model for studying basic functions of the eukaryotic genome and simultaneously provides valuable information towards further refinement of this technique. Several examples discussed below illustrate how DD coupled with classical yeast genetic approaches may be used for studying transcriptionally regulated genetic systems. [ABSTRACT FROM AUTHOR]

The article presents information on a system of primers developed for amplification of the array of nitrogenase genes in bacteria, which covers the maximum possible diversity of diazotrophs. It reports that amplification of nitrogenase structural genes, using degenerate oligonucleotide primers in polymerase chain reaction, is the simplest method of assessing the nitrogen-fixing ability in different prokaryotes. The system of primers was tested with 14 collection strains of diazotrophic bacteria of different taxonomic positions. It reports that most methanotrophic bacteria have been found to be diazotrophs.

Abstract: It is likely that large-conductance Ca2+-activated K+ (BKCa) channels channelopathy tightly involved in vascular malfunctions and arterial hypertension development. In the present study, we compared the results of siRNAs-induced α-BKCa gene silencing and vascular abnormalities produced by whole-body ionized irradiation in rats. The experimental design comprised RT-PCR and patch clamp technique, thoracic aorta smooth muscle (SM) contractile recordings and arterial blood pressure (BP) measurements on the 30th day after whole body irradiation (6Gy) and following siRNAs KCNMA1 gene silencing in vivo. The expression profile of BKCa mRNA transcripts in SM was significantly decreased in siRNAs-treated rats in a manner similar to irradiated SM. In contrast, the mRNA levels of K v and K ATP were significantly increased while L-type calcium channels mRNA transcripts demonstrated tendency to increment. The SMCs obtained from irradiated animals and after KCNMA1 gene silencing showed a significant decrease in total K+ current density amplitude. Paxilline (500 nM)-sensitive components of outward current were significantly decreased in both irradiated and gene silencing SMCs. KCNMA1 gene silencing increased SM sensitivity to norepinephrine while Ach-induced relaxation had decreased. The silencing of KCNMA1 had no significant effect on BP while radiation produced sustained arterial hypertension. Therefore, radiation alters the form and function of the BKCa channel and this type of channelopathy may contribute to related vascular abnormalities. Nevertheless, it is unlikely that BKCa can operate as a crucial factor for radiation-induced arterial hypertension. [Copyright &y& Elsevier]

Abstract: Parkinson''s disease (PD) is the second most common progressive neurodegenerative disorder characterized by the degeneration of dopaminergic neurons. Detecting changes in gene expression in untreated de novo patients with PD is important for understanding disease pathogenesis and for identifying biomarkers for preclinical stage of PD. In this study we investigate ST13 gene expression in the peripheral blood of different groups of patients with neurological diseases using reverse transcription reaction and real-time polymerase chain reaction (PCR). Our results suggest that the expression levels of ST13 cannot serve as a biomarker for early stages of PD. [Copyright &y& Elsevier]