Functional connexin35 increased in the myopic chicken retina.

Our previous research showed that increased phosphorylation of connexin (Cx)36 indicated extended  coupling of AII amacrine cells (ACs) in the rod-dominant mouse myopic retina. This research will determine whether phosphorylation at serine 276 of Cx35-containing gap junctions increased in the myopic chicken, whose retina is cone-dominant. Refractive errors and ocular biometric dimensions of 7-days-old chickens were determined following 12 h and 7 days induction of myopia by a -10D lens. The expression pattern and size of Cx35-positive plaques were examined in the early (12 h) and compensated stages (7 days) of lens-induced myopia (LIM). At the same time, phosphorylation at serine 276 (functional assay) of Cx35 in strata 5 (S5) of the inner plexiform layer was investigated. The axial length of the 7 days LIM eyes was significantly longer than that of non-LIM controls (P < 0.05). Anti-phospho-Ser276 (Ser276-P)-labeled plaques were significantly increased in LIM retinas at both 12 h and 7 days. The density of Ser276-P of Cx35 was observed to increase after 12 h LIM. In the meanwhile, the areas of existing Cx35 plaques did not change. As there was more phosphorylation of connexin35 at Ser276 at both the early and late stages (12 h) and 7 days of LIM chicken retinal activity, the coupling with ACs could be increased in myopia development of the cone-dominated chicken retina.

JAK1/2 pathway inhibition suppresses M2 polarization and overcomes resistance of myeloma to lenalidomide by reducing TRIB1, MUC1, CD44, CXCL12, and CXCR4 expression.

Monocytes polarize into pro-inflammatory macrophage-1 (M1) or alternative macrophage-2 (M2) states with distinct phenotypes and physiological functions. M2 cells promote tumour growth and metastasis whereas M1 macrophages show anti-tumour effects. We found that M2 cells were increased whereas M1 cells were decreased in bone marrow (BM) from multiple myeloma (MM) patients with progressive disease (PD) compared to those in complete remission (CR). Gene expression of Tribbles homolog 1 (TRIB1) protein kinase, an inducer of M2 polarization, was increased in BM from MM patients with PD compared to those in CR. Ruxolitinib (RUX) is an inhibitor of the Janus kinase family of protein tyrosine kinases (JAKs) and is effective for treating patients with myeloproliferative disorders. RUX markedly reduces both M2 polarization and TRIB1 gene expression in MM both in vitro and in vivo in human MM xenografts in severe combined immunodeficient mice. RUX also downregulates the expression of CXCL12, CXCR4, MUC1, and CD44 in MM cells and monocytes co-cultured with MM tumour cells; overexpression of these genes is associated with resistance of MM cells to the immunomodulatory agent lenalidomide. These results provide the rationale for evaluation of JAK inhibitors, including MM BM in combination with lenalidomide, for the treatment of MM patients.

Evaluations of Lifestyle, Dietary, and Pharmacologic Treatments for Pediatric Nonalcoholic Fatty Liver Disease: A Systematic Review.

BACKGROUND & AIMS: There are no approved treatments for pediatric nonalcoholic fatty liver disease (NAFLD) and there is a lack of consensus on the best outcome measure for randomized controlled trials. We performed a systematic review of treatments tested for pediatric NAFLD, the degree of heterogeneity in trial design, and endpoints analyzed in these studies. METHODS: We searched publication databases and clinical trial registries through January 7, 2018 for randomized controlled trials (published and underway) of children (<18 years) with NAFLD. We assessed improvements in histologic features, radiologic and biochemical markers of reduced fibrosis, metabolic syndrome parameters, and adverse events. The quality of the trials was assessed using a modified version of the Cochrane risk of bias tool. RESULTS: Our final analysis included 21 randomized controlled trials, comprising 1307 participants (mean age, 12.6 years; 63% male; mean duration of intervention, 8 months). Most studies evaluated weight loss with lifestyle intervention (n=8), oral polyunsaturated fatty acid treatment (PUFAs, n=6), or oral antioxidant treatment (n=7). Biomarkers of NAFLD decreased with weight loss, but most studies did not include histologic data. Trials of antioxidants were heterogeneous; some reported reduced histologic features of steatohepatitis with no effect on triglycerides or insulin resistance. PUFAs and probiotics reduced radiologic markers of steatosis, insulin resistance, and levels of triglycerides. Only 38% of the trials had biopsy-proven NAFLD as an inclusion criterion. There was heterogeneity in trial primary endpoints; 10 studies (48%) used levels of aminotransferases or ultrasonography findings as a primary endpoint and only 3 trials (14%) used histologic features as the primary endpoint. We identified 13 randomized controlled trials that are underway in children with NAFLD. None of the protocols include collection of liver biopsies; 9 trials (69%) will use magnetic resonance imaging quantification of steatosis as a primary outcome. CONCLUSIONS: In a systematic review of published and active randomized controlled trials of children with NAFLD, we found a large amount of heterogeneity in study endpoints and inclusion criteria. Few trials included histologic analyses. Antioxidants appear to reduce some features of steatohepatitis. Effects of treatment with lifestyle modification, PUFAs, or probiotics have not been validated with histologic analysis. Trials that are underway quantify steatosis magnetic resonance imaging-outcomes are anticipated.

The anti-myeloma effects of the selective JAK1 inhibitor (INCB052793) alone and in combination in vitro and in vivo.

The Janus kinase (JAK) pathway has been shown to play key roles in the growth and resistance to drugs that develop in multiple myeloma (MM) patients. The anti-MM effects of the selective JAK1 inhibitor INCB052793 (INCB) alone and in combination with anti-MM agents were evaluated in vitro and in vivo. Significant inhibition of cell viability of primary MM cells obtained fresh from MM patients, and the MM cell lines RPMI8226 and U266, was observed with single agent INCB and was enhanced in combination with other anti-MM agents including proteasome inhibitors and glucocorticosteroids. Single-agent INCB resulted in decrease in tumor growth of the MM xenograft LAGκ-1A growing in severe combined immunodeficient mice. Mice dosed with INCB (30 mg/kg) showed significant reductions in tumor volume on days 28, 35, 42, 49, 56, and 63. Similarly, INCB at 10 mg/kg showed anti-tumor effects on days 56 and 63. Tumor-bearing mice receiving combinations of INCB with carfilzomib, bortezomib, dexamethasone, or lenalidomide showed significantly smaller tumors when compared to vehicle control and mice treated with single agents. These results provide further support for the clinical evaluation of INCB052793 alone and in combination treatment for MM patients.

Site-Specific Quantification of Surface N-Glycoproteins in Statin-Treated Liver Cells.

The frequent modification of cell-surface proteins by N-linked glycans is known to be correlated with many biological processes. Aberrant glycosylation on surface proteins is associated with different cellular statuses and disease progression. However, it is extraordinarily challenging to comprehensively and site-specifically analyze glycoproteins located only on the cell surface. Currently mass spectrometry (MS)-based proteomics provides the possibility to analyze the N-glycoproteome, but effective separation and enrichment methods are required for the analysis of surface glycoproteins prior to MS measurement. The introduction of bio-orthogonal groups into proteins accelerates research in the robust visualization, identification, and quantification of proteins. Here we have comprehensively evaluated different sugar analogs in the analysis of cell-surface N-glycoproteins by combining copper-free click chemistry and MS-based proteomics. Comparison of three sugar analogs, N-azidoacetylgalactosamine (GalNAz), N-azidoacetylglucosamine (GlcNAz), and N-azidoacetylmannosamine (ManNAz), showed that metabolic labeling with GalNAz resulted in the greatest number of glycoproteins and glycosylation sites in biological duplicate experiments. GalNAz was then employed for the quantification experiment in statin-treated HepG2 liver cells, and 280 unique N-glycosylated sites were quantified from 168 surface proteins. The quantification results demonstrated that many glycosylation sites on surface proteins were down-regulated in statin-treated cells compared to untreated cells because statin prevents the synthesis of dolichol, which is essential for the formation of dolichol-linked precursor oligosaccharides. Several glycosylation sites in proteins that participate in the Alzheimer's disease pathway were down-regulated. This method can be extensively applied for the global analysis of the cell-surface N-glycoproteome.

Dynamic heterogeneity of DNA methylation and hydroxymethylation in embryonic stem cell populations captured by single-cell 3D high-content analysis.

UNLABELLED: Cell-surface markers and transcription factors are being used in the assessment of stem cell fate and therapeutic safety, but display significant variability in stem cell cultures. We assessed nuclear patterns of 5-hydroxymethylcytosine (5hmC, associated with pluripotency), a second important epigenetic mark, and its combination with 5-methylcytosine (5mC, associated with differentiation), also in comparison to more established markers of pluripotency (Oct-4) and endodermal differentiation (FoxA2, Sox17) in mouse embryonic stem cells (mESC) over a 10-day differentiation course in vitro: by means of confocal and super-resolution imaging together with 3D high-content analysis, an essential tool in single-cell screening. IN SUMMARY: 1) We did not measure any significant correlation of putative markers with global 5mC or 5hmC. 2) While average Oct-4 levels stagnated on a cell-population base (0.015 lnIU/day), Sox17 and FoxA2 increased 22-fold and 3-fold faster, respectively (Sox17: 0.343 lnIU/day; FoxA2: 0.046 lnIU/day). In comparison, global DNA methylation levels increased 4-fold faster (0.068 lnIU/day), and global hydroxymethylation declined at 0.046 lnIU/day, both with a better explanation of the temporal profile. 3) This progression was concomitant with the occurrence of distinct nuclear codistribution patterns that represented a heterogeneous spectrum of states in differentiation; converging to three major coexisting 5mC/5hmC phenotypes by day 10: 5hmC(+)/5mC(-), 5hmC(+)/5mC(+), and 5hmC(-)/5mC(+) cells. 4) Using optical nanoscopy we could delineate the respective topologies of 5mC/5hmC colocalization in subregions of nuclear DNA: in the majority of 5hmC(+)/5mC(+) cells 5hmC and 5mC predominantly occupied mutually exclusive territories resembling euchromatic and heterochromatic regions, respectively. Simultaneously, in a smaller subset of cells we observed a tighter colocalization of the two cytosine variants, presumably delineating chromatin domains in remodeling. We conclude that 1) 5mC emerges as the most differential marker in our model system. 2) However, the combined enrollment of the two DNA modifications provided higher-definition screening and lead to the identification of cell subpopulations based on differential 5hmC/5mC phenotypes corresponding to different 5hmC/5mC ratios. The results encourage: a) assessing the regenerative potential of early-endodermal cells enriched for the three DNA methylation/hydroxymethylation categories, and b) exploring the universality of this type of epigenetic phenotyping across other lineage-specific differentiations.

Systematic investigation of cellular response and pleiotropic effects in atorvastatin-treated liver cells by MS-based proteomics.

For decades, statins have been widely used to lower cholesterol levels by inhibiting the enzyme HMG Co-A reductase (HMGCR). It is well-known that statins have pleiotropic effects including improving endothelial function and inhibiting vascular inflammation and oxidation. However, the cellular responses to statins and corresponding pleiotropic effects are largely unknown at the proteome level. Emerging mass spectrometry-based proteomics provides a unique opportunity to systemically investigate protein and phosphoprotein abundance changes as a result of statin treatment. Many lipid-related protein abundances were increased in HepG2 cells treated by atorvastatin, including HMGCR, FDFT, SQLE, and LDLR, while the abundances of proteins involved in cellular response to stress and apoptosis were decreased. Comprehensive analysis of protein phosphorylation demonstrated that several basic motifs were enriched among down-regulated phosphorylation sites, which indicates that kinases with preference for these motifs, such as protein kinase A and protein kinase C, have attenuated activities. Phosphopeptides on a group of G-protein modulators were up-regulated, which strongly suggests that cell signal rewiring was a result of the effect of protein lipidation by the statin. This work provides a global view of liver cell responses to atorvastatin at the proteome and phosphoproteome levels, which provides insight into the pleiotropic effects of statins.

Effect of in vitro transcription conditions on yield of high quality messenger and self-amplifying RNA.

Messenger RNA (mRNA) and self-amplifying RNA (saRNA) vaccines against SARS-CoV-2 produced using in vitro transcription (IVT) were clinically approved in 2020 and 2022, respectively. While the industrial production of mRNA using IVT has been extensively optimized, the optimal conditions for saRNA have been explored to a lesser extent. Most T7 polymerase IVT protocols have been specifically optimized for mRNA which is ∼5-10-fold smaller than saRNA and may have profound effects on both the quality and yield of longer transcripts. Here, we optimized IVT conditions for simultaneously increasing the yield of full-length transcripts and reducing dsRNA formation through Design of Experiments. Using a definitive screening approach, we found that the key parameters are temperature and magnesium in the outcome of RNA quality (% full length transcript) and yield in small scale synthesis. The most important parameter for reducing dsRNA formation for both mRNA and saRNA was Mg2+ concentration (10 mM). We observed that a lower temperature was vital for production of high quality saRNA transcripts. mRNA quality was optimal at higher Mg2+ concentration (>40 mM). High quality transcripts correspond to significantly reduced product yield for saRNA, but not for mRNA. The differences between mRNA and saRNA requirements for high quality product and the relationship between high quality large saRNA molecules and low temperature synthesis have not been reported previously. These findings are key for informing future IVT parameters design and optimization for smaller and larger RNA transcripts.

Shortened Duration of Dual Antiplatelet Therapy Following Percutaneous Coronary Intervention: A Contemporary Clinical Review.

Percutaneous coronary intervention with stent implantation is an integral aspect of minimally interventional cardiac procedures. The technology and techniques behind stent design and implantation have evolved rapidly over several decades. However, continued discourse remains around optimal peri- and post-interventional management with dual antiplatelet therapy to minimise both major cardiovascular or cerebrovascular events and iatrogenic bleeding risk. Standard guidelines around dual antiplatelet therapy historically recommended long-term dual antiplatelet therapy for 12 months (with consideration for >12 months in certain patients); however, emerging data and generational improvements in the safety of drug-eluting stents have ushered in a new era of short-term therapy to reduce the incidence of major bleeding events. This case review will provide an overview of the current state of guidelines around duration of dual antiplatelet therapy and examine recent updates and continued gaps in existing research.

Chronic upper back and rib pain in a healthy man: re-examining the cause.

INTRODUCTION Back and rib pain is a common presentation in primary care practice. Although most cases are secondary to non-specific musculoskeletal pain, it is essential for clinicians to identify patients presenting with life-threatening pathologies. AIM This case report serves as a reminder to clinicians to reconsider their initial diagnosis when a patient's pain fails to improve, while considering life-threatening pathologies. CASE HISTORY We describe a 44-year-old man from India who presents to his general practitioner with a 2-week history of rib and upper back pain. He was initially diagnosed with non-specific musculoskeletal pain. However, after representing twice 2 months later due to persistent pain and due to the uncertainty about his condition, he was investigated with different imaging modalities. It was discovered on bone scan that he had osteolytic lesions in the right 11th rib and T2 vertebrae. As the cause of his osteolytic lesions were unclear, he was referred to different specialists. Skeletal tuberculosis was suspected when one of his specialists discovered his recent visit to India, a tuberculosis-endemic country. This reminded the specialist of the possible risks of the patient's background and its association with his symptoms. Bone biopsy of his lytic lesions revealed Mycobacterium tuberculosis, consistent with skeletal tuberculosis. DISCUSSION Revisiting the diagnosis of back and rib pain while considering other obscure and urgent pathologies is essential if a patient fails to improve clinically. Clinicians should focus on aspects of their clinical assessment to explore these pathologies, enabling earlier recognition of the disease.

Increased Connexin36 Phosphorylation in AII Amacrine Cell Coupling of the Mouse Myopic Retina.

Myopia is a substantial public health problem worldwide. In the myopic retina, distant images are focused in front of the photoreceptors. The cells and mechanisms for retinal signaling that account either for emmetropization (i.e., normal refraction) or for refractive errors have remained elusive. Gap junctions play a key component in enhancement of signal transmission in visual pathways. AII amacrine cells (ACs), coupled by connexin36, segregate signals into ON and OFF pathways. Coupling between AII ACs is actively modulated through phosphorylation at serine 293 via dopamine in the mouse retina. In this study, form deprivation mouse myopia models were used to evaluate the expression patterns of connexin36-positive plaques (structural assay) and the state of connexin36 phosphorylation (functional assay) in AII ACs, which was green fluorescent protein-expressing in the Fam81a mouse line. Single-cell RNA sequencing showed dopaminergic synapse and gap junction pathways of AII ACs were downregulated in the myopic retina, although Gjd2 mRNA expression remained the same. Compared with the normal refractive eye, phosphorylation of connexin36 was increased in the myopic retina, but expression of connexin36 remained unchanged. This increased phosphorylation of Cx36 could indicate increased functional gap junction coupling of AII ACs in the myopic retina, a possible adaptation to adjust to the altered noisy signaling status.

Anxiety and depression in Chinese patients attending an Australian GP clinic.

BACKGROUND: Incidence of depression among Chinese people living in traditional Asian regions is low. Recent Chinese immigrants to Australia may be at greater risk of depression and anxiety because of issues related to integration into Australian society. General practitioners are often the first point of contact for people with anxiety and depression. Patients from a Chinese background may be reluctant to discuss their mental health problems with their GP. METHODS: A cross sectional survey was undertaken of Chinese patients 18 years of age and over attending a general practice in southwestern Sydney (New South Wales) during July 2005. Patients were asked to complete the Kessler Psychological Distress Scale (K10) and Somatic and Psychological Health Report (SPHERE) depression screening questionnaires, along with a demographic questionnaire. All questionnaires were available in English or Chinese. RESULTS: A total of 161 patients completed the questionnaires. Fifty-five percent (83) of patients had a K10 score that indicated medium or high risk, and 44% (71) had a high SPHERE score (PSYCH-6 and/or SOMA-6). There was an association between increased risk of depression or anxiety and reduced occupational status but not social isolation. DISCUSSION: Half the Chinese patients presenting at this general practice were at high risk of psychological distress (as measured by standard screening instruments). The proportion of patients in this study at risk of psychological distress on screening is more than would be expected in the general Australian population. Though limited by a small sample size and a single general practice location, these findings are of concern and should direct further research.

Serum B-cell maturation antigen (BCMA) reduces binding of anti-BCMA antibody to multiple myeloma cells.

B-cell maturation antigen (BCMA), a tumor necrosis factor receptor (TNFR) family member, is selectively expressed on terminally differentiated B-lymphocytes including multiple myeloma (MM) tumor cells. We sought to determine whether circulating (c)BCMA in MM serum interferes with antiBCMA antibody binding to MM cells. An enzyme-linked immunosorbent assay (ELISA) was used to determine serum (s) BCMA levels among 379 samples from patients with relapsed/refractory MM (RRMM). Furthermore, flow cytometric and immunofluorescent studies were used to examine if concentrations of BCMA in patients' serum were high enough to interfere with the binding of anti-BCMA antibody to MM tumor cells. We have shown that BCMA is elevated in the serum from MM patients and that the median concentration of sBCMA from RRMM patients was 176 ng/mL (n = 379). Additionally, there was a consistent decrease in the binding of anti-BCMA antibody to MM tumor cells with sBCMA level ≥156 ng/mL. Together, these results demonstrate that circulating BCMA levels in most RRMM patients are high enough to interfere with anti-BCMA antibody binding to MM tumor cells and may interfere with BCMA-targeted immune-based therapies.

The clinical significance of B-cell maturation antigen as a therapeutic target and biomarker.

INTRODUCTION: B-cell maturation antigen (BCMA) is a cell membrane bound tumor necrosis factor receptor family member that is expressed exclusively on late stage normal and malignant B-cells and plasma cells. Addition of two of its ligands, B-cell activating factor and a proliferation inducting ligand, to normal B-cells cause B-cell proliferation and antibody production. Serum BCMA is elevated among patients with multiple myeloma (MM) and chronic lymphocytic leukemia (CLL), and is a prognostic and monitoring tool for these patients. The first anti-BCMA antibody (Ab) was developed in 2007. Recently, biotech and pharmaceutical companies have created various forms of BCMA-directed Abs (naked Abs, Ab drug conjugates, and bispecific Abs) and cellular therapies (chimeric antigen receptor T-cells) with promising clinical results. Areas covered: This BCMA review encompasses full-text publications of original research articles and abstracts presented at hematology/oncology meetings. Expert commentary: The limited preclinical and ongoing clinical studies published to date evaluating BCMA-directed therapies have shown great promise. It has also been demonstrated that BCMA is solubilized and elevated in the blood of MM, Waldenstrom's macroglobulinemia and CLL patients, and is also responsible for the immune deficiency in MM. Reducing circulating levels may improve the efficacy of these treatments.