Up-regulation of acid-sensing ion channels in the capsule of the joint in frozen shoulder

The purpose of this study was to evaluate the expression of acid-sensing ion channels (ASICs) in the capsule and synovial fluid of patients with frozen shoulder. Capsular tissue and synovial fluid were obtained from 18 patients with idiopathic frozen shoulder (FS group) and 18 patients with instability of the shoulder (control group). The expressions of ASIC1, ASIC2, and ASIC3 in the capsule were determined using the reverse transcriptase-polymerase chain reaction, immunoblot analysis, and immunohistochemistry (IHC). The concentrations in synovial fluid were evaluated using an enzyme-linked immunosorbent assay.

The mRNA expression of ASIC1, ASIC2 and ASIC3 in the capsule were significantly increased in the FS group compared with the control group. The protein levels of these three ASICs were also increased. The increased expressions were confirmed by IHC. Of the ASICs, ASIC3 showed the greatest increase in both mRNA and levels of expression compared with the control group. The levels of ASIC1 and ASIC3 in synovial fluid were significantly increased in the FS group.

This study suggests that ASICs may play a role as mediators of inflammatory pain and be involved in the pathogenesis of frozen shoulder.

Cite this article: Bone Joint J 2015;97-B:824–9.

A novel antibody-drug conjugate targeting SAIL for the treatment of hematologic malignancies

Although several new therapeutic approaches have improved outcomes in the treatment of hematologic malignancies, unmet need persists in acute myeloid leukemia (AML), multiple myeloma (MM) and non-Hodgkin's lymphoma. Here we describe the proteomic identification of a novel cancer target, SAIL (Surface Antigen In Leukemia), whose expression is observed in AML, MM, chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). While SAIL is widely expressed in CLL, AML, MM, DLBCL and FL patient samples, expression in cancer cell lines is mostly limited to cells of AML origin. We evaluated the antitumor activity of anti-SAIL monoclonal antibodies, 7-1C and 67-7A, conjugated to monomethyl auristatin F. Following internalization, anti-SAIL antibody–drug conjugates (ADCs) exhibited subnanomolar IC₅₀ values against AML cell lines in vitro. In pharmacology studies employing AML cell line xenografts, anti-SAIL ADCs resulted in significant tumor growth inhibition. The restricted expression profile of this target in normal tissues, the high prevalence in different types of hematologic cancers and the observed preclinical activity support the clinical development of SAIL-targeted ADCs.

Factors that influence activities of daily living in the elderly with probable dementia

The purpose of this study was to identify the factors that influence activities of daily living (ADL) in the elderly with probable dementia. The participants were 152 older adults who voluntarily visited a hospital to participate in a national dementia free screening programme. General characteristics, health-related characteristics, ADL, Mini-Mental State Examination Korean Consortium (MMSE-KC) and the Geriatric Depression Scale (GDS) score were evaluated in this study. The data were analysed using independent t-tests, Pearson's correlation and stepwise multiple regression. The ADL score of the participants was 14.3, and 88.2% of the participants were severe cognitive disorder. ADL scores were positively related with MMSE-KC scores (r = 0.35, P < 0.001) and negatively with GDS scores (r = -0.20, P = 0.014). Factors that influenced ADL were faecal and urinary incontinence, regularity of exercise, MMSE-KC score and stroke history; these five variables explained 30.8% of the ADL score for the elderly with probable dementia. Multidisciplinary interventions are essential to improve the ADL and prevent deterioration of cognitive function in elderly patients with probable dementia.

Apoptosis in endothelial cells by cyclosporine

OBJECTIVES

The immunosuppressive drug cyclosporine (CsA) is a potent agent widely used after organ transplantations and to treat various autoimmune disorders. After using CsA, some patients suffer severe complications including renal and vascular toxicity, which are influenced by the degree of the endothelial damage. Several studies have demonstrated CsA treatment to directly induce apoptosis in several cell types. Thus, CsA may induce endothelial damage via activation of proapoptotic proteins. The present study was undertaken to investigate the effects of CsA on apoptosis of endothelial cells using human umbilical vein endothelial cells.

METHODS

Proliferation was measured by using the Cell Counting Assay Kit after cells were exposed to CsA (0 L, 10 L, 30 L, 50 L or 100 μg/mL). Apoptotic cells were identified by fluorescence microscopy of 4', 6-diamidino-2-phenylidole-stained nuclei. Western blot analysis was done for poly(ADP-ribose) polymerase (PARP), p27, p53 and caspase.

RESULTS

Cell viability decreased dependent on the CsA concentration. CsA treatment group showed chromatin condensation and nuclear fragmentation. CsA produced a dose-dependent induction of p27 and reduction of procasapase-3. CsA treatment induced the degradation of 116-kDa PARP into an 89-kDa fragment.

CONCLUSIONS

CsA induced apoptosis of endothelial cells.

Apoptotic effect of hesperidin through caspase3 activation in human colon cancer cells, SNU-C4

Hesperidin, a known flavonoid constituent of citrus, reduces the proliferation of many cancer cells. The apoptotic effects of hesperidin on human colon cancer cells, SNU-C4, were determined at concentrations of 1-100 microM. At 100 microM, hesperidin reduced cell viability to 65.00+/-0.05% of control values in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell death induced by hesperidin showed apoptotic features in 4,6-diamidino-2-phenylindole (DAPI) staining and in terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assays. Examination of the expression of apoptosis-regulating genes indicated that hesperidin treatment decreased the expression of B-cell CLL/lymphoma 2 (BCL2) mRNA, and increased the expression of BCL2-associated X protein (BAX). The expression and activity of the major apoptotic factor caspase3 (CASP3) was increased significantly with hesperidin treatment. Hesperidin down-regulated the protein expression of pro-CASP3, and up-regulated the level of active CASP3. Thus, these results suggest that hesperidin could induce apoptosis in human colon cancer cells through CASP3 activation.

Topiramate stimulates glucose transport through AMP-activated protein kinase-mediated pathway in L6 skeletal muscle cells

The use of topiramate (TPM) in the treatment of binge-eating disorder, bulimia nervosa, and antipsychotic-induced weight gain has recently increased, however, the exact molecular basis for its effects on body weight reduction and improved glucose homeostasis, is yet to be elucidated. Here we investigated the effect and signaling pathway of TPM on glucose uptake in L6 rat skeletal muscle cells, which account for >70% of glucose disposal in the body. Intriguingly, we found that TPM (10 microM) stimulated the rate of glucose uptake up to twofold increase. And TPM-stimulated glucose transport was inhibited with the overexpression of dominant-negative form of AMP-activated protein kinase (AMPK), an important mediator in glucose transport, implicating that AMPK-mediated pathway is involved. The TPM-stimulated glucose transport was blocked by SB203580, a specific inhibitor of AMPK downstream mediator, p38 mitogen-activated protein kinase (MAPK) protein. LY294002, an inhibitor of phosphatidylinositol (PI) 3-kinase, which is another crucial mediator in independent glucose transport pathway, did not inhibit TPM-stimulated glucose transport. We also found that TPM increased the phosphorylation level of AMPK and p38 MAPK, whereas no effect on the activity of PI 3-kinase of TPM, when assessed by PI 3-kinase assay, was observed. These results together suggest that TPM stimulates glucose transport, not via PI 3-kinase mediated, but via AMPK-mediated pathway in skeletal muscle cells, thereby contributing to the body weight regulation and glucose homeostasis.

Prevalence of methicillin-resistant and methicillin-susceptible Staphylococcus aureus in the community

Recent reports indicate that community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections are increasing and may now involve persons without risk factors predisposing for acquisition. To estimate the extent of community MRSA in New York City, the prevalence of S. aureus and MRSA nasal colonization in a well-patient population of 500 children and guardians was determined. The prevalence of S. aureus nasal carriage was 35% for children and 28% for guardians. One person with predisposing risk factors was colonized with an MRSA, which was identified as the predominant clone found in New York City hospitals. A high degree of methicillin-susceptible S. aureus strain diversity was noted, with no apparent selection for specific clonal types. Thus, MRSA colonization is not ubiquitous in persons without predisposing risk outside of the health care environment. Bacterial competition and a lack of strong selection may limit the community spread of MRSA and can account for its sporadic distribution.

The human homologue of Bub3 is required for kinetochore localization of Bub1 and a Mad3/Bub1-related protein kinase

A feedback control mechanism, or cell cycle checkpoint, delays the onset of anaphase until all the chromosomes are correctly aligned on the mitotic spindle. Previously, we showed that the murine homologue of Bub1 is not only required for checkpoint response to spindle damage, but also restrains progression through a normal mitosis (Taylor, S.S., and F. McKeon. 1997. Cell. 89:727-735). Here, we describe the identification of a human homologue of Bub3, a 37-kD protein with four WD repeats. Like Bub1, Bub3 localizes to kinetochores before chromosome alignment. In addition, Bub3 and Bub1 interact in mammalian cells. Deletion mapping was used to identify the domain of Bub1 required for binding Bub3. Significantly, this same domain is required for kinetochore localization of Bub1, suggesting that the role of Bub3 is to localize Bub1 to the kinetochore, thereby activating the checkpoint in response to unattached kinetochores. The identification of a human Mad3/Bub1-related protein kinase, hBubR1, which can also bind Bub3 in mammalian cells, is described. Ectopically expressed hBubR1 also localizes to kinetochores during prometaphase, but only when hBub3 is overexpressed. We discuss the implications of the common interaction between Bub1 and hBubR1 with hBub3 for checkpoint control.

The Caenorhabditis elegans NK-2 homeobox gene ceh-22 activates pharyngeal muscle gene expression in combination with pha-1 and is required for normal pharyngeal development

Pharyngeal muscle development in the nematode Caenorhabditis elegans appears to share similarities with cardiac muscle development in other species. We have previously described CEH-22, an NK-2 class homeodomain transcription factor similar to Drosophila tinman and vertebrate Nkx2-5, which is expressed exclusively in the pharyngeal muscles. In vitro, CEH-22 binds the enhancer from myo-2, a pharyngeal muscle-specific myosin heavy chain gene. In this paper, we examine the role CEH-22 plays in pharyngeal muscle development and gene activation by (a) ectopically expressing ceh-22 in transgenic C. elegans and (b) examining the phenotype of a ceh-22 loss-of-function mutant. These experiments indicate that CEH-22 is an activator of myo-2 expression and that it is required for normal pharyngeal muscle development. However, ceh-22 is necessary for neither formation of the pharyngeal muscles, nor for myo-2 expression. Our data suggest parallel and potentially compensating pathways contribute to pharyngeal muscle differentiation. We also examine the relationship between ceh-22 and the pharyngeal organ-specific differentiation gene pha-1. Mutations in ceh-22 and pha-1 have strongly synergistic effects on pharyngeal muscle gene expression; in addition, a pha-1 mutation enhances the lethal phenotype caused by a mutation in ceh-22. Wild-type pha-1 is not required for the onset of ceh-22 expression but it appears necessary for maintained expression of ceh-22.

In vivo stability of heterogeneous expression classes in clinical isolates of methicillin-resistant staphylococci

To define the stability of methicillin-resistant Staphylococcus aureus (MRSA) in vivo, 22 isolates collected at one New York institution in 1989 and 1990 were studied. All 22 belonged to one of two distinct methicillin-resistant phenotypes (class 3 or 2), which were precisely identified as belonging to two distinct genotypes. Genotypic classification was based on restriction analysis of chromosomal DNA with EcoRI and HindIII and Southern analysis of ClaI digests using two DNA probes. One was specific for the mec gene; the other was specific for transposon Tn554. The findings suggest that the MRSA isolates studied were representative of two genetically distinct MRSA "clones," each with a unique strain-specific methicillin-resistant phenotype that is stable under the conditions of invasive disease, carriage, and spread from patient to patient.