To identify biomarker candidates associated with early IgA nephropathy (IgAN) and thin basement membrane nephropathy (TBMN), the most common causes presenting isolated hematuria in childhood, a proteomic approach of urinary exosomes from early IgAN and TBMN patients was introduced. The proteomic results from the patients were compared with a normal group to understand the pathophysiological processes associated with these diseases at the protein level. The urinary exosomes, which reflect pathophysiological processes, collected from three groups of young adults (early IgAN, TBMN, and normal) were trypsin-digested using a gel-assisted protocol, and quantified by label-free LC-MS/MS, using an MS(E) mode. A total of 1877 urinary exosome proteins, including cytoplasmic, membrane, and vesicle trafficking proteins, were identified. Among the differentially expressed proteins, four proteins (aminopeptidase N, vasorin precursor, α-1-antitrypsin, and ceruloplasmin) were selected as biomarker candidates to differentiate early IgAN from TBMN. We confirmed the protein levels of the four biomarker candidates by semi-quantitative immunoblot analysis in urinary exosomes independently prepared from other patients, including older adult groups. Further clinical studies are needed to investigate the diagnostic and prognostic value of these urinary markers for early IgAN and TBMN. Taken together, this study showed the possibility of identifying biomarker candidates for human urinary diseases using urinary exosomes and might help to understand the pathophysiology of early IgAN and TBMN at the protein level.

Since cAMP blocks meiotic maturation of mammalian and amphibian oocytes in vitro and cyclic nucleotide phosphodiesterase 3A (PDE3A) is primarily responsible for oocyte cAMP hydrolysis, we generated PDE3A-deficient mice by homologous recombination. The Pde3a -/-females were viable and ovulated a normal number of oocytes but were completely infertile, because ovulated oocytes were arrested at the germinal vesicle stage and, therefore, could not be fertilized. Pde3a -/-oocytes lacked cAMP-specific PDE activity, contained increased cAMP levels, and failed to undergo spontaneous maturation in vitro (up to 48 hours). Meiotic maturation in Pde3a -/-oocytes was restored by inhibiting protein kinase A (PKA) with adenosine-3′,5′-cyclic monophosphorothioate, Rp-isomer (Rp-cAMPS) or by injection of protein kinase inhibitor peptide (PKI) or mRNA coding for phosphatase CDC25, which confirms that increased cAMP-PKA signaling is responsible for the meiotic blockade. Pde3a -/-oocytes that underwent germinal vesicle breakdown showed activation of MPF and MAPK, completed the first meiotic division extruding a polar body, and became competent for fertilization by spermatozoa. We believe that these findings provide the first genetic evidence indicating that resumption of meiosis in vivo and in vitro requires PDE3A activity. Pde3a -/-mice represent an in vivo model where meiotic maturation and ovulation are dissociated, which underscores inhibition of oocyte maturation as a potential strategy for contraception.

Over time, peritoneal dialysis results in functional and structural alterations of the peritoneal membrane, but the underlying mechanisms and whether these changes are reversible are not completely understood. Here, we studied the effects of high levels of glucose, which are found in the dialysate, on human peritoneal mesothelial cells (HPMCs). We found that high concentrations of glucose induced epithelialto-mesenchymal transition (EMT) of HPMC, suggested by decreased expression of E-cadherin and increased expression of ␣-smooth muscle actin, fibronectin, and type I collagen and by increased cell migration. Normalization of glucose concentration on day 2 reversed the phenotypic transformation, but the changes were irreversible after 7 d of stimulation with high glucose. In addition, exposure of HPMC to high glucose resulted in a decreased expression of the antifibrotic cytokines, hepatocyte growth factor (HGF) and bone morphogenic protein 7 (BMP-7). Exogenous treatment with HGF resulted in a dosage-dependent prevention of high glucose-induced EMT. Both BMP-7 peptide and gene transfection with an adenoviral vector of BMP-7 also protected HPMCs from EMT. Furthermore, adenoviral BMP-7 transfection decreased peritoneal EMT and ameliorated peritoneal thickening in an animal model of peritoneal dialysis. In summary, high concentrations of glucose induce a reversible EMT of HPMCs, associated with decreased production of HGF and BMP-7. Treatment of HPMCs with HGF or BMP-7 blocks high glucose-induced EMT, and BMP-7 ameliorates peritoneal fibrosis in an animal model of peritoneal dialysis.

The coronavirus disease (COVID-19) pandemic has posed a challenge for healthcare systems, and healthcare workers (HCWs) are at high risk of exposure. Protecting HCWs is of paramount importance to maintain continuous patient care and keep healthcare systems functioning. Used alongside administrative and engineering control measures, personal protective equipment (PPE) is the last line of defense and the core component of protection. Current data suggest that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is mainly transmitted through respiratory droplets and close contact. Airborne transmission may occur during aerosol-generating procedures. However, the modes of transmission still remain uncertain, especially regarding the possibility of airborne transmission when aerosolgenerating procedures are not performed. Thus, there are some inconsistencies in the respiratory protective equipment recommended by international and national organizations. In Korea, there have been several modifications to PPE recommendations offering options in choosing PPE for respiratory and body protection, which confuses HCWs; they are often unsure what to wear and when to wear it. The choice of PPE is based on the risk of exposure and possible modes of transmission. The level of protection provided by PPE differs based on standards and test methods. Thus, understanding them is the key in selecting the proper PPE. This article reviews evidence on the mode of SARS-CoV-2 transmission, compares the current PPE recommendations of the World Health Organization with those in Korea, and discusses standard requirements and the proper selection of PPE.

Detachment of epithelial cells from matrix or attachment to an inappropriate matrix engages an apoptotic response known as anoikis, which prevents metastasis. Cellular sensitivity to anoikis is compromised during the oncogenic epithelial-to-mesenchymal transition (EMT), through unknown mechanisms. We report here a pathway through which EMT confers anoikis resistance. NRAGE (neurotrophin receptor-interacting melanoma antigen) interacted with a component of the E-cadherin complex, ankyrin-G, maintaining NRAGE in the cytoplasm. Oncogenic EMT downregulated ankyrin-G, enhancing the nuclear localization of NRAGE. The oncogenic transcriptional repressor protein TBX2 interacted with NRAGE, repressing the tumor suppressor gene p14ARF. P14ARF sensitized cells to anoikis; conversely, the TBX2/NRAGE complex protected cells against anoikis by downregulating this gene. This represents a novel pathway for the regulation of anoikis by EMT and E-cadherin.Metastatic tumor cells survive detachment from their extracellular matrix of origin and/or attachment to inappropriate matrices for extended periods of time, conditions that engage an apoptotic response known as anoikis in normal cells. Tumor cell resistance to anoikis is driven by (epi)genetic alterations or aberrant signaling responses that occur uniquely in the tumor microenvironment, leading to constitutive activation of integrin/growth factor signaling and inactivation of the core apoptotic machinery (23, 27, 28, 30-32, 76, 87).The oncogenic epithelial-to-mesenchymal transition (EMT) is thought to play an important role in tumor progression (46,88,91). The focus of the present study was to understand the molecular basis of the tight correlation between anoikis resistance and the oncogenic EMT (31,51,54,68,89). A common hallmark of EMT is the breakdown of E-cadherin expression or function (103), which suffices to circumvent anoikis in some contexts. For example, the targeted knockout of the E-cadherin gene in a mouse mammary tumor model or the stable knockdown of E-cadherin in a mammary epithelial cell line confers anoikis resistance (19,68). This implies that EMTpromoting transcription factors such as ZEB1/2, Snail1/2 and Twist can abrogate anoikis both by directly regulating apoptosis control genes and by suppressing E-cadherin expression, the latter triggering signaling events-to be addressed here-that control other apoptosis regulatory genes (46,53,75,85,89,92).Ankyrin-G plays a critical role in linking the actin cytoskeleton to the cell membrane and in the biogenesis of the lateral membrane domain of epithelial cells. The N-terminal ankyrin repeat domain interacts with E-cadherin, linking the latter to the cytoskeleton via interaction with spectrin complexes. Accordingly, ankyrin-G localizes primarily to adherens junctions (50,65,73). In addition, ankyrin-G contains two domains, a death domain and a ZU-5 domain, whose homologues in other proteins regulate apoptosis (99, 101). The downregulation of the ankyrin-G gene (ank3) correlates with poor prognosis in diverse human...

This study aimed to compare health-related quality of life (HRQOL) over time in patients initiating hemodialysis (HD) or peritoneal dialysis (PD). A total of 989 incident patients starting HD or PD were included from a prospective nationwide cohort study. HRQOL was assessed 3, 12, and 24 months after the start of dialysis. The scores of questionnaires were adjusted for clinical and socioeconomic parameters. The adjusted three months scores of patients on PD showed better HRQOL in eight end-stage renal disease (ESRD), three physical component summary and one mental component summary domains compared with patients on HD. Both patients on HD and PD experienced significant decreases in different HRQOL domains over two years and the degree of changes in HRQOL over time was not different between dialysis modality. However, the scores of three (effects of kidney disease, burden of kidney disease, and dialysis staff encouragement, all P < 0.05) and two (sexual function and dialysis staff encouragement, all P < 0.05) ESRD domains were still higher in patients on PD compared with patients on HD at one and two years after initiation of dialysis, respectively. PD shows better HRQOL during the initial period after dialysis even after adjusting for clinical and socioeconomic characteristics, and the effect lasts up to two years. It was similar in terms of changes in HRQOL over time between HD and PD.

No abstract

Due to significant improvements in current therapies, the life expectancy of cancer patients with bone metastases has dramatically improved. Unfortunately, these patients often experience skeletal complications that significantly impair their quality of life. The major skeletal complications associated with bone metastases include: cancer-induced bone pain, hypercalcemia, pathological bone fractures, metastatic epidural spinal cord compression, and cancer cachexia. Once cancer cells invade the bone, they perturb the normal physiology of the marrow microenvironment, resulting in bone destruction, which is believed to be a direct cause of skeletal complications. However, full understanding of the mechanisms responsible for these complications remains unknown. In this review, we will discuss the complications associated with bone metastases along with matched conventional therapeutic strategies. A better understanding of this topic is crucial, since targeting skeletal complications can improve both morbidity and mortality of patients suffering from bone metastases.