Autophagy of mucin granules contributes to resolution of airway mucous metaplasia.

Exacerbations of muco-obstructive airway diseases such as COPD and asthma are associated with epithelial changes termed mucous metaplasia (MM). Many molecular pathways triggering MM have been identified; however, the factors that regulate resolution are less well understood. We hypothesized that the autophagy pathway is required for resolution of MM by eliminating excess non-secreted intracellular mucin granules. We found increased intracellular levels of mucins Muc5ac and Muc5b in mice deficient in autophagy regulatory protein, Atg16L1, and that this difference was not due to defects in the known baseline or stimulated mucin secretion pathways. Instead, we found that, in mucous secretory cells, Lc3/Lamp1 vesicles colocalized with mucin granules particularly adjacent to the nucleus, suggesting that some granules were being eliminated in the autophagy pathway rather than secreted. Using a mouse model of MM resolution, we found increased lysosomal proteolytic activity that peaked in the days after mucin production began to decline. In purified lysosomal fractions, Atg16L1-deficient mice had reduced proteolytic degradation of Lc3 and Sqstm1 and persistent accumulation of mucin granules associated with impaired resolution of mucous metaplasia. In normal and COPD derived human airway epithelial cells (AECs), activation of autophagy by mTOR inhibition led to a reduction of intracellular mucin granules in AECs. Our findings indicate that during peak and resolution phases of MM, autophagy activity rather than secretion is required for elimination of some remaining mucin granules. Manipulation of autophagy activation offers a therapeutic target to speed resolution of MM in airway disease exacerbations.

Noxa/HSP27 complex delays degradation of ubiquitylated IkBα in airway epithelial cells to reduce pulmonary inflammation.

IFN-γ is known as a pro-inflammatory cytokine, but can also block inflammation in certain chronic diseases although the underlying mechanisms are poorly understood. We found that IFN-γ rapidly induced Noxa expression and that extent of inflammation by repeated house dust mite exposure was enhanced in noxa-/- compared with noxa+/+ mice. Noxa expression blocked transforming necrosis factor alpha (TNF-α)-induced nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and the production of pro-inflammatory cytokines. Noxa did not affect TNF-α-induced IκBα phosphorylation but the degradation of 48-chain-ubiquitylated IκBα. The Cys25 of Noxa was cross-linked with Cys137 of phospho-HSP27 and both proteins were required for blocking the degradation of ubiquitylated IκBα. Because phospho-HSP27 is present in airway epithelial cells and not in fibroblasts or thymocytes, we generated transgenic mice that inducibly expressed Noxa in airway epithelia. These mice showed protection from allergen-induced inflammation and mucous cell metaplasia by blocking nuclear translocation of NF-κB. Further, we identified a Noxa-derived peptide that prolonged degradation of 48-chain-ubiquitylated IκBα, blocked nuclear translocation of NF-κB, and reduced allergen-induced inflammation in mice. These results suggest that the anti-inflammatory role of the Noxa protein may be restricted to airway epithelial cells and the use of Noxa for therapy of chronic lung diseases may be associated with reduced side effects.

Novel adaptations to zinc-silicate glass polyalkenoate cements: the unexpected influences of germanium based glasses on handling characteristics and mechanical properties.

Aluminum-free glass polyalkenoate cements (GPC) have been hindered for use as injectable bone cements by their inability to balance handling characteristics with mechanical integrity. Currently, zinc-based, aluminum-free GPCs demonstrate compression strengths in excess of 60MPa, but set in c. 1-2 min. Previous efforts to extend the setting reaction have remained clinically insufficient and are typically accompanied by a significant drop in strength. This work synthesized novel glasses based on a zinc silicate composition with the inclusion of GeO2, ZrO2, and Na2O, and evaluated the setting reaction and mechanical properties of the resultant GPCs. Germanium based GPCs were found to have working times between 5 and 10 min, setting times between 14 and 36 min, and compression strengths in excess of 30 MPa for the first 30 days. The results of this investigation have shown that the inclusion of GeO2, ZrO2, and Na2O into the glass network have produced, for the first time, an aluminum-free GPC that is clinically viable as injectable bone cements with regards to handling characteristics and mechanical properties.

Demographic and clinical characteristics of cutaneous lupus erythematosus at a paediatric dermatology referral centre.

BACKGROUND: Paediatric cutaneous lupus erythematosus (CLE) is uncommon and inadequately described in the literature. Similar to adults, children with CLE develop LE-specific and/or LE-nonspecific skin findings. Similarities and differences in demographics and clinical course between paediatric and adult CLE have not been sufficiently described. OBJECTIVES: To detail the demographic and clinical features of paediatric CLE and compare these findings with those reported in the adult literature. METHODS: A retrospective chart review was performed of 53 children seen in a paediatric dermatology clinic with cutaneous manifestations of LE. RESULTS: Patients presented with all five major subtypes of CLE, with some notable differences from adult CLE and previously published reports of paediatric CLE. Progression from discoid LE to systemic LE (SLE) did not occur in our cohort. Patients with subacute CLE were more likely than adults to have lesions below the waist as well as concomitant SLE. Sex distribution for CLE in our study was equal prior to puberty and female predominant in post-pubertal patients. CONCLUSIONS: Children with CLE have variable clinical presentations and progression to SLE that may be different from adult disease. Specifically, children with acute and subacute CLE may be more likely than adults to have systemic disease; therefore, patients with these subtypes should be monitored closely for evidence of SLE. Study limitations included small patient numbers that may limit the ability to generalize these data and relatively short follow-up intervals.

Norovirus outbreaks: a systematic review of commonly implicated transmission routes and vehicles.

Causal mechanisms of norovirus outbreaks are often not revealed. Understanding the transmission route (e.g. foodborne, waterborne, or environmental) and vehicle (e.g. shellfish or recreational water) of a norovirus outbreak, however, is of great public health importance; this information can facilitate interventions for an ongoing outbreak and regulatory action to limit future outbreaks. Towards this goal, we conducted a systematic review to examine whether published outbreak information was associated with the implicated transmission route or vehicle. Genogroup distribution was associated with transmission route and food vehicle, but attack rate and the presence of GII.4 strain were not associated with transmission route, food vehicle, or water vehicle. Attack rate, genogroup distribution, and GII.4 strain distribution also varied by other outbreak characteristics (e.g. setting, season, hemisphere). These relationships suggest that different genogroups exploit different environmental conditions and thereby can be used to predict the likelihood of various transmission routes or vehicles.

The epidemiology of published norovirus outbreaks: a review of risk factors associated with attack rate and genogroup.

The purpose of this study was to examine global epidemiological trends in human norovirus (NoV) outbreaks by transmission route and setting, and describe relationships between these characteristics, viral attack rates, and the occurrence of genogroup I (GI) or genogroup II (GII) strains in outbreaks. We analysed data from 902 reverse transcriptase-polymerase chain reaction-confirmed, human NoV outbreaks abstracted from a systematic review of articles published from 1993 to 2011 and indexed under the terms 'norovirus' and 'outbreak'. Multivariate regression analyses demonstrated that foodservice and winter outbreaks were significantly associated with higher attack rates. Foodborne and waterborne outbreaks were associated with multiple strains (GI+GII). Waterborne outbreaks were significantly associated with GI strains, while healthcare-related and winter outbreaks were associated with GII strains. These results identify important trends for epidemic NoV detection, prevention, and control.

In silico evaluation of stress distribution after vertebral body augmentation with conventional acrylics, composites and glass polyalkenoate cements.

There exists clinical evidence of fractures in adjacent vertebrae subsequent to vertebral augmentation procedures, such as vertebroplasty (VP) and kyphoplasty (KP). A potential contributory factor to such fractures may be the excessive mismatch of mechanical properties between contemporary bone cements (i.e. polymethyl methacrylate (PMMA) and bisphenol-a-glycidyl dimethacrylate (BIS-GMA)) and bone. Aluminum-free glass polyalkenoate cements (GPCs) present an interesting alternative to conventional bone cements. GPCs adhere to the philosophy that implant materials should have mechanical characteristics similar to those of the bone, and also offer chemical adhesion and intrinsic bioactivity. However, their influence on the loading patterns of augmented vertebrae (as compared with conventional bone cements) is not available in the literature. The present work investigates how the moduli of PMMA, BIS-GMA and GPC implants affect the stress distribution within a single, augmented vertebra, in both healthy and osteoporotic states. Using a finite element model of the L4 vertebra derived from computed tomography data, with simulated augmentation, it was found that, as cement stiffness increased, stress was redistributed from the cortical and trabecular bone to the cement implant. The GPC implant exhibited the least effect on stress redistribution in both the healthy and osteoporotic models compared to its acrylic counterparts. The significance of this work is that, under simulated physiological loading conditions, aluminum-free GPCs exhibit stress distribution throughout the vertebral body similar to that of the healthy bone. In comparison to conventional augmentation materials, the use of aluminum-free GPCs in VP and KP may help to ameliorate the clinical complication of adjacent vertebral body compression fractures.

New perspectives regarding ß(2) -adrenoceptor ligands in the treatment of asthma.

In the last two decades several significant changes have been proposed in the receptor theory that describes how ligands can interact with G protein-coupled receptors (GPCRs). Here we briefly summarize the evolution of receptor theory and detail recent prominent advances. These include: (i) the existence of spontaneously active GPCRs that are capable of signalling even though they are unoccupied by any ligand; (ii) the discovery of ligands that can inactivate these spontaneously active receptors; (iii) the notion that a ligand may simultaneously activate more than one GPCR signalling pathway; and (iv) the notion that certain ligands may be able to preferentially direct receptor signalling to a specific pathway. Because the data supporting these receptor theory ideas are derived primarily from studies using artificial expression systems, the physiological relevance of these new paradigms remains in question. As a potential example of how these new perspectives in receptor theory relate to drug actions and clinical outcomes, we discuss their relevance to the recent controversy regarding the chronic use of ß(2) -adrenoceptor agonists in the treatment of asthma.

Inhaled corticosteroids stabilize constrictive bronchiolitis after hematopoietic stem cell transplantation.

Post transplantation constrictive bronchiolitis (PTCB) is the most common pulmonary complication among long-term survivors of allogeneic hematopoietic stem cell transplantation (HSCT). It is a late manifestation of GVHD. Its treatment with high-dose systemic corticosteroids and other immunosuppressive regimens is associated with multiple side effects. Topical corticosteroids are used for the treatment of other manifestations of GVHD to minimize these side effects. We conducted a retrospective analysis of a series of adult patients to evaluate the efficacy of high-dose inhaled corticosteroids in the treatment of PTCB. Seventeen patients with new-onset airflow obstruction were diagnosed with PTCB. Their forced expiratory volume in 1 s (FEV1) declined from a median of 84% (range, 56-119) before HSCT to 53% (26-82) after HSCT. All patients received inhaled fluticasone propionate 500-940 microg two times daily. Symptoms of airway obstruction improved and FEV1 stabilized 3-6 months after treatment. We conclude that high-dose inhaled corticosteroids may be effective in the treatment of PTCB and propose a plausible mechanism of its action. A prospective evaluation of its efficacy is warranted.

Outcome of alveolar hemorrhage in hematopoietic stem cell transplant recipients.

Alveolar hemorrhage (AH) is a frequent, serious complication of hematopoietic stem cell transplantation (HSCT). To study the incidence of AH, its clinical course and outcomes in HSCT patients, a retrospective review of the records of all adult patients who underwent bronchoscopy between January 1, 2002 and December 31, 2004 was carried out and those who underwent bronchoscopy after HSCT identified. A total of 223 patients underwent bronchoscopy after HSCT for diffuse pulmonary infiltrates with respiratory compromise. Eighty-seven (39%) patients had AH. Of these, 53 had AH without any identified organism while 34 had an organism along with hemorrhage on bronchoalveolar lavage (BAL). Six-month survival rate of patients with AH was 38% (95% confidence interval: 27-48%). In 95 of the 223 patients, an organism was isolated from BAL. These patients had poor outcomes compared to patients in whom no organism was identified. Patients with both AH and an organism had the worst prognosis. Mortality of patients with AH is improving and long-term survival of patients with AH is feasible. Isolation of a microbial organism in BAL is a strong predictor of poor outcome.

Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors for infection, 1997-2004.

In order to elucidate the spectrum of Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors, 44 cancer patients (cases) with S. maltophilia pneumonia in whom S. maltophilia pneumonia risk factors were not present were compared with two S. maltophilia pneumonia risk groups (controls) including 43 neutropenic non-intensive care unit (ICU) and 21 non-neutropenic ICU patients. The case and control patients had similar demographic and underlying clinical characteristics. Compared with case patients with S. maltophilia pneumonia, neutropenic patients had higher exposure to carbapenem antibiotics (58 vs. 41%; p < 0.03), more frequent hematologic malignancy (95 vs. 64%; p < 0.0003), and they presented with concurrent bacteremia more often (23 vs. 0%; p < 0.0005). Patients with S. maltophilia pneumonia in the ICU needed vasopressor therapy more frequently than cases (62 vs. 5%; p < 0.0001). Hospital-acquired S. maltophilia pneumonia was more common among controls than cases (98 vs. 61%; p < 0.000002). Among the cases, 15 (34%) received outpatient oral antimicrobial therapy, while 29 were hospitalized and eight (28%) were subsequently admitted to the ICU. The mean duration of ICU stay, even among these eight patients (19 +/- 40 days), was comparable to that of patients with neutropenia (23 +/- 26 days) and those who developed S. maltophilia pneumonia during their ICU stay (34 +/- 22 days; p = 0.46). The overall infection-associated mortality in the 108 patients with S. maltophilia pneumonia was 25%. Twenty percent of patients without traditional risk factors for S. maltophilia pneumonia died due to progressive infection. In a multivariate logistic regression analysis, only admission to the ICU predicted death (odds ratio 33; 95% confidence interval, 4.51-241.2; p < 0.0006). The results of this study indicate S. maltophilia pneumonia is a serious infection even in non-neutropenic, non-ICU patients with cancer.

Inhibition of mucin secretion with MARCKS-related peptide improves airway obstruction in a mouse model of asthma.

Allergic asthma is associated with airway epithelial cell mucous metaplasia and mucin hypersecretion, but the consequences of mucin hypersecretion on airway function are unclear. Recently, a peptide derived from the myristoylated alanine-rich C kinase substrate protein NH(2)-terminal sequence (MANS) was shown to inhibit methacholine (MCh)-induced mucin secretion from airway mucous cells by >90%. We studied the effect of intranasal pretreatment with this peptide on specific airway conductance (sGaw) during challenge with MCh in mice with allergen-induced mucous cell metaplasia. sGaw was noninvasively measured in spontaneously breathing restrained mice, using a double-chamber plethysmograph. Pretreatment with MANS peptide, but not a control peptide [random NH(2)-terminal sequence (RNS)], resulted in partial inhibition of the fall in sGaw induced by 60 mM MCh (mean +/- SE; baseline 1.15 +/- 0.06; MANS/MCh 0.82 +/- 0.05; RNS/MCh 0.55 +/- 0.05 cmH(2)O/s). The protective effect of MANS was also seen in mice challenged with allergen for 3 consecutive days to increase airway hyperresponsiveness, although the degree of protection was less (baseline 1.1 +/- 0.08; MANS/MCh, 0.65 +/- 0.06; RNS/MCh 0.47 +/- 0.03 cmH(2)O/s). Because routine sGaw measurement in mice includes nasal airways, the effectiveness of MANS was also confirmed in mice breathing through their mouths after nasal occlusion (baseline 0.92 +/- 0.05; MANS/MCh 0.83 +/- 0.06; RNS/MCh 0.61 +/- 0.03 cmH(2)O/s). In all instances, sGaw in the MANS-pretreated group was approximately 35% higher than in RNS-treated controls, and mucous obstruction accounted for approximately 50% of the MCh-induced fall in sGaw. In summary, mucin secretion has a significant role in airway obstruction in a mouse model of allergic asthma, and strategies to inhibit mucin secretion merit further investigation.

Traffic control: Rab GTPases and the regulation of interorganellar transport.

Membrane proteins, membrane lipids, and luminal contents are exchanged among the intracellular compartments of eukaryotic cells by vesicular transport. This process must be highly ordered to maintain cellular architecture in the face of rapid membrane turnover. The Ras-related Rab GTPases play multiple roles in regulating this traffic.

Managed care and children's behavioral health services in Massachusetts.

OBJECTIVE: The authors investigated changes in treatment patterns and costs of care for children after the implementation of the Massachusetts Medicaid carve-out managed care plan. METHODS: The authors hypothesized that after the introduction of managed care, per-child expenditures would be reduced, continuity of care would not improve, and per-child mental health expenditures would undergo larger reductions for disabled children, compared with children enrolled in the Aid to Families With Dependent Children program. Using data from Medicaid and the Massachusetts Department of Mental Health, the authors studied 16,664 Massachusetts Medicaid beneficiaries aged one to 17 years for whom reimbursement claims were submitted for psychiatric or substance use disorder treatment at least once during the two years before the introduction of managed care (1991 to 1992) or during the two years afterward (1994 to 1995). Multivariate analysis was used to estimate changes in probability of admission, and, among patients admitted, to identify factors accounting for variation in length of stay. To assess the variation in expenditures, we regressed the same variables, using the natural logarithm function to transform total mental health expenditures data and inpatient expenditures data to reduce skewness. RESULTS: After the introduction of managed care, per-child expenditures were lower, especially for disabled children, and the Department of Mental Health was used as a safety net for the most seriously ill children without increasing state expenditures. Continuity of care appeared to decline for disabled children. CONCLUSIONS: It is likely that a combination of factors related to the reported changes in patterns of care and expenditures were responsible for the overall per-child expenditures.

Review of programs for persons who are homeless and mentally ill.

Despite recent prosperity in the U.S., homelessness is still a widespread social problem. It is estimated that 25% of homeless persons have a serious mental illness. This article will review the literature evaluating prevention services and specialized outreach, treatment, and housing programs designed to reduce homelessness for individuals who are mentally ill. Although these interventions have been helpful in addressing the complex needs of the homeless mentally ill, it is difficult to measure how they have improved outcomes. It is even more challenging to determine whether the programs are cost-effective. Since public resources are used to maintain services for the homeless mentally ill, policy-makers must be informed about whether the best outcomes are achieved at the lowest possible cost. Following a discussion of the successes of the individual programs and the challenges they confront, several important questions are identified related to improving the efficiency of these programs. Although the establishment of such programs indicates that progress has been made toward alleviating the burdens facing people who are homeless and mentally ill, collaboration among all stakeholders-especially between the mental health community and consumer advocates-needs to be further enhanced. New research can be conducted in a way that improves how information is evaluated and used.

Gene structure and promoter function of murine Munc18-2, a nonneuronal exocytic Sec1 homolog.

Sec1 family proteins are regulators of diverse exocytic processes, from yeast to man. Three mammalian homologues, Munc18-1, -2, and -3 have been described. We have studied the structure and expression of the mouse Munc18-2 gene. The Munc18-2 gene comprises 19 exons whose sizes range from 50 to 158 bp, with a total gene size of approximately 11 kb. A single transcript of 2.1 kb is expressed in multiple non-neuronal murine tissues. Munc18-2 has a striking resemblance to Munc18-1 in structure despite only 60% sequence identity, suggesting a recent gene duplication event. Analysis of the region upstream of the transcription start site shows that Munc18-2 has a TATA-less promoter, with a consensus initiator (Inr) sequence at the start of transcription, several Sp1 binding sites, and strong promoter activity in RBL-2H3 mast cells. The region from +5 to -430 is more active than +5 to -800, suggesting upstream repressor elements.

Outcome assessment in women's mental health.

This is the fifth in a series of six papers that will be published from the 1999 lecture series on "Quality Assessment in Women's Health Care" held at the University of Michigan School of Public Health. The lectures are presented by leaders in women's health research, and they explore key issues in the definition, measurement, and improvement of quality in women's health services. The series is supported by an unrestricted educational grant from Pfizer Inc. and is presented by the Interdepartmental Concentration in Reproductive and Women's Health at the University of Michigan School of Public Health; the University of Michigan National Center of Excellence in Women's Health; and the Michigan Initiative for Women's Health. The series coordinator is Carol S. Weisman, PhD, and Catherine L. Maroney prepared the summary of the discussants' comments.

Genomic organization, chromosomal localization, and expression of the murine RAB3D gene.

Rab proteins, members of the Ras superfamily of small GTPases, play regulatory roles in intercompartmental vesicular transport. Each step of traffic seems to require the participation of at least one distinct Rab, with the Rab3 subfamily involved in stimulated exocytosis. We report our studies on the murine rab3D gene, one of the four mammalian Rab3 isoforms. We located this gene on chromosome 13, region A(2-3). The rab3D gene consists of 5 exons spanning 10.6 kb, and the structural gene is contained in exons 2 through 5 with one canonical GTP-binding motif in each exon. Organization of the rab3D gene is identical to that of rab3A but different from other rab genes. Alternative poly-A(+) signals in the 3' untranslated region account for the identities of multiple transcripts detected by Northern blot analysis. Rab3D is expressed in all tissues studied, predominantly in heart, lung, and liver, and binding sites for multiple transcription factors are found in the TATA-less promoter region.