Inhibition of cysteine proteinases by autolytic digestion is mediated by CBP2/Hsp47

CBP2/Hsp47 is a glycoprotein normally limited to the ER-Golgi where it is first associated with procollagen chains at a very early point during translation of nascent chains and later with properly folded procollagen. Although CBP2/Hsp47 is regarded as a molecular chaperone belonging to the serpin superfamily, this protein does not appear to inhibit serine proteinases. Here we demonstrate that CBP2/Hsp47 functions in a manner similar to other serpin superfamily members by cross class inhibiting cysteine proteinases. A CBP2/Hsp47 to cathepsin L inactivation stoichiometery of approximately 1.5 revealed concurrent cleavage of CBP2/Hsp47 with proteinase inactivation. Cleavage of the CBP2/Hsp47 was shown to occur outside the P1-P1' at the P16-P15 and P2'-P3' bonds. In addition, the proteinase bands in SDS/PAGE diminished on reaction of the enzyme with CBP2/Hsp47. These results sustain a mechanism advocated by Bjork et al. (1998), in which cysteine proteinases assault a peptide bond in the reactive site loop of serpins, (CBP2/Hsp47) adjacent to the P1-P1' bonds involved in serine proteinase inhibition. The reaction proceeds with the substrate pathway dominating in the cysteine proteinase reaction. In these complexes the cysteine proteinases, papain and cathepsin L, are rendered more susceptible to proteolysis and are degraded by active enzyme. These properties help explain the mechanism by which CBP2/Hsp47 increases the fidelity of collagen production. Moreover, if CBP2/Hsp47 is shown to involve the multiplexin subclass of collagens, it may further provide a mechanism by which the motogen and angiogenic properties during development and/or neoplasia are regulated.     

An immunocytochemical study of isolated human retinal Müller tells in culture

Background: We report a modified method for the isolation and propagation of adult human Müller cells in culture. Methods: The retina of postmortem human eyes was mechanically dissociated and cultured. Using immunocytochemical techniques, these cells were stained with monoclonal antibodies specific for Müller cells, glial fibrillary acidic protein (GFAP), vimentin, glutamine synthetase (GS) and keratin. Transmission electron microscopy (TEM) was also performed. Results: The dissociated and cultured cells expressed vimentin and GS, but not GFAP. At least 85% of these cells stained with a Müller tell-specific monoclonal antibody. Using TEM, flat cells containing 13-nm intermediate filaments and glycogen were identified. Conclusion: Human retinal Müller cells tan be isolated and propagated in culture. Purified cell cultures are required for controlled studies of the normal physiology and pathologie responses of Müller cells.     

Predictive factors of local-regional recurrences following parotid sparing intensity modulated or 3D conformal radiotherapy for head and neck cancer.

BACKGROUND AND PURPOSE: Predictive factors for local-regional (LR) failures after parotid-sparing, Intensity modulated (IMRT) or 3D conformal radiotherapy for head and neck (HN) cancers were assessed. PATIENTS AND METHODS: One hundred and fifty-eight patients with mostly stages III-IV HN squamous cell carcinoma underwent curative bilateral neck irradiation aimed at sparing the parotid glands. Patient, tumor, and treatment factors were analyzed as predictive factors for LR failure. RESULTS: Twenty-three patients had LR recurrence (19 in-field and four marginal). No differences were found in the doses delivered to the PTVs of patients with or without in-field recurrences. In univariate analysis, tumor site was highly predictive for LR failure in both postoperative and definitive RT patients. In postoperative RT patients, pathologic tumor size, margin status, extracapsular extension (ECE) and number of lymph node metastases, were also significantly predictive. Multivariate analysis showed tumor site (oropharynx vs. other sites) to be a significant predictor in all patients, and involved margins and number of involved lymph nodes in postoperative patients. CONCLUSIONS: Clinical rather than dosimetric factors predicted for LR failures in this series, and were similar to those reported following standard RT. These factors may aid in the selection of patients for studies of treatment intensification using IMRT.     

Psychiatric Comorbidity in Women with Disordered Eating Behavior: A National Study

ABSTRACT

This study used data collected by Statistics Canada in the Mental Health and Well-being cycle of the Canadian Community Health Survey (N = 20,211) to examine the associations between disordered eating behavior and selected mood, anxiety and substance use disorders in adult women grouped in three age groups. Significant associations between disordered eating behaviors and major depression, substance dependence and psychological distress were found for women in all three age ranges. Prevalence of specific classes of anxiety disorders in women who reported disordered eating behaviors differed according to their age. Having disordered eating behaviors was significantly associated with both 12-month and lifetime prevalence of social phobia for women above 25 years of age. Lifetime prevalence of agoraphobia was associated with disordered eating behaviors in women 15–44 years old, and the 12-month prevalence was associated with disordered eating behaviors only in women 15–24 years of age. Disordered eating behaviors were significantly associated with lifetime prevalence of panic disorder in women in all three age ranges and with 12-month prevalence of panic disorder in women in two age ranges, 15–24 and 45 and above. The findings highlight the importance of taking age into consideration when developing assessment instruments and treatment strategies to address the co-occurrence of eating disorders and other psychiatric disorders.     

Prevention series introduction

Abstract

A group of 29 obese women with Binge Eating Disorder (OB-BED) and 35 obese subjects without this disorder (OB) were compared on the presence or absence of traumatic experiences and dissociative symptoms with the Dissociation Questionnaire (DIS-Q). OB-BED subjects showed significantly higher scores on two subscales of the DIS-Q (identity confusion and loss of control). They also reported significantly more traumatic experiences than the OB sample. These data further support the assumption that among eating disorder patients, both traumatic experiences and dissociative symptoms are more prevalent when patients show serious binge eating.     

Androgen receptor in salivary gland carcinoma: A review of an old marker as a possible new target

The role of the androgen receptor (AR) as an immunomarker for diagnosis of salivary gland duct carcinoma (SDC) is well known. Other non‐squamous cell head and neck cancers (NSCC‐HN), including a small subset of salivary gland cancers (SGCs), can also express AR. With the increase in effective and powerful new generation of anti‐androgen agents and drugs administered orally, more targetable AR‐driven NSCC‐HN, such as subsets of SGCs, should be investigated for possible expression of AR. In this review, we focus on SGC subtypes, which could express AR and describe the main androgen deprivation therapy (ADT) strategies.     

Prevalence of intestinal parasitic pathogens among HIV-positive individuals in Iran

Parasites are important enteric pathogens among patients with human immunodeficiency virus (HIV) infection. There have been very few reports on the prevalence of intestinal parasites among such patients in Iran. To determine the prevalence of intestinal parasites among HIV-positive individuals, we collected single stool samples and analyzed them for detection of various intestinal parasites from 206 HIV-positive individuals with different immune status visited in different medical centers in Iran. The data were tested for statistical significance with chi(2) and Mann-Whitney U tests. The overall prevalence of intestinal parasites was 18.4% (95%CI: 13.7, 24.3). More specifically, the following parasites were identified: Giardia lamblia (7.3%), Blastocystis hominis (4.4%), Entamoeba coli (3.9%), and Cryptosporidium parvum (1.5%). Other parasites observed included Strongyloides stercoralis and Hymenolepis nana in two cases and Dicrocoelium dendriticum in one. Of the 38 patients who tested positive for intestinal parasites, 15 (39.2%) had diarrhea. Intestinal parasites were significantly more common among patients with diarrhea than those without (P < 0.001). Further, CD4 counts were significantly lower among individuals with diarrhea than those without (P < 0.001). This study highlights the importance of testing for intestinal parasites among Iranian HIV-positive patients, especially those with low immunity presenting with diarrhea.     

The interplay of DAMPs,TLR4, and proinflammatory cytokines in pulmonary fibrosis

Journal of Molecular Medicine - Pulmonary fibrosis is a chronic debilitating condition characterized by progressive deposition of connective tissue, leading to a steady restriction of lung...