In this study we have shown that translocation of intestinal LPS into the portal and systemic circulatory systems during graft-versus-host disease (GVHD) is predictive of morbidity and mortality. Randomized C57BL/6 x AF1 (B6AF$ sb1$) mice were injected with C57BL/6 (B6) lymphoid cells and sacrificed at predetermined times after transplantation for bacterial lipopolysaccharide (LPS) tissue analysis. The liver, the spleen and the sera from some acute GVH reactive mice first tested positive for LPS from day 2, 4 and 16 post transplant, respectively. Total hepatic and splenic LPS in acute GVH reactive mice peaked, and LPS was first detected in the sera of these same animals, at a time coincident with the onset of mortality. These results show that LPS is present to initiate tumour necrosis factor alpha (TNF-$ alpha$) release from interferon gamma (IFN-$ gamma$) primed macrophages, resulting in the manifestations of acute GVHD.

New tests to diagnose active tuberculosis (TB) that are simple, rapid and inexpensive, yet sensitive and specific are urgently needed. We assessed the sensitivity and specificity of seven different M. tuberculosis antigens for the diagnosis of active pulmonary TB in The Gambia. Three of the antigens tested were restricted, i.e. absent from BCG and some non-tuberculous mycobacteria (ESAT6, CFP-10 and Rv3871), and four shared, i.e. common to most mycobacteria (38kDa, GLU-S, 19kDa and 14kDa). Sera from 100 patients with active pulmonary TB, 100 household contacts, and 100 healthy neighborhood controls, in the Gambia, were tested by ELISA for antibodies to these 7 antigens. The sensitivity and specificity of both the shared and the restricted antigens were unacceptably low. In countries with high, rates of TB, such as the Gambia, the clinical utility of serologic testing to diagnose active tuberculosis remains limited.

Rationale. Idiopathic pulmonary fibrosis in humans is associated with chronic cigarette smoking. At present only an acute model exists for lung fibrosis research. Objective. Describe a chronic animal model of lung fibrosis produced by cigarette smoke exposure. Methods. Six BALB/c mice have been exposed to two unfiltered cigarettes a day, 5 days a week for 6 months. Results. The phenotype was characterized by lung mechanics, histology and gene expression. Tissue elastance (compliance) and resistance was observed to be significantly elevated in the cigarette smoke-exposed mice compared to untreated controls. Histologically, airspace size in lungs of smoke exposed mice assessed by mean Linear Intercept and percent area of tissue was significantly decreased and increased respectively compared to controls. Inflammatory cell counting resulted in a significant increase in neutrophils in experimental mice. Assessment of Collagen type I clearly demonstrated a prominent interstitial deposition in smoke-exposed mice compared to controls. Conclusions. These data demonstrate that BALB/c mice are susceptible to the development of pulmonary fibrosis following chronic cigarette smoke exposure. This model could be an important contribution to the study of idiopathic pulmonary fibrosis in humans.

The goal of this thesis was to elucidate the physicochemical and metabolic bases of Hyperapobetalipoproteinemia (HyperapoB). This disorder, which is likely the commonest metabolic abnormality associated with premature coronary artery disease, was defined as a combination of a normal, or near-normal, LDL cholesterol in the face of an elevated LDL apoB. / LDL, even in normals, is heterogeneous. The experimental findings herein confirm this. They also extend this concept to indicate that familial hypercholesterolemia (FH) and HyperapoB each imprint LDL in different and characteristic ways, each an exaggeration of the typical relations between LDL composition and size in normals. At one extreme is HyperapoB, which is characterized by most of the LDL particles being smaller and denser than normal because they contain less cholesteryl ester but the same amount of apoB as normal. At the other is FH, which is characterized by larger, cholesteryl ester-enriched particles. There is, as well, a predictable relation between LDL particle size and the immunoreactivity of certain apoB epitopes. / Turnover studies of hepatic apoB using traditional analytic models showed that hepatic apoB is overproduced in HyperapoB, a finding which stands in marked contrast to the impaired catabolism of apoB in FH. A new multi-compartmental model of LDL metabolism has been developed which appears to elucidate several of the basic mechanisms involved in the pathogenesis of HyperapoB. All the data to date indicate that the characteristic abnormalities of LDL in HyperapoB are all consequences of the overproduction of hepatic apoB. Obviously, the goal for future research must be to understand the basis for this overproduction. A preliminary study with adipose tissue suggested that the overproduction of hepatic apoB might be secondary to a defect in peripheral tissue triglyceride biosynthesis.

Chemokines, small molecular weight chemotactic cytokines, are produced mostly by airway epithelial cells and are known to play an instrumental role in the recruitment of inflammatory cells. Studies have documented a dramatic increase in the chemokine levels in the airways of asthmatics and many other studies have shown the induction of these chemokines by cytokines and growth factors in airway epithelial cells in vitro. Thus, given the high levels of chemokines in asthmatic airways and abundant evidence supporting strong interactions between cytokines and epithelial cells, we hypothesized that chemokine receptors are present on airway epithelium, and that chemokines may act through these receptors to increase mucin production. Here we demonstrate constitutive expression of chemokine receptors CCR3, CCR5 and CXCR4 in the A549 cell line by Western blot and RT-PCR. / The results of this study show that chemokine receptors are present on airway epithelial cells and that chemokines may act as a stimulus for epithelial cell mucin gene expression. Our novel finding that several CC chemokines upregulate the expression of MUC5AC mRNA might be an important mechanism regulating airway epithelial cell phenotype and function under conditions of inflammation in asthma.

We conducted a molecular epidemiologic study of tuberculosis (TB) transmission during the years 1996--98 on the Island of Montreal. By combining public health data on the 528 reported cases with IS6110 DNA fingerprints for 430, we detected an overall low frequency of transmission manifesting as secondary cases of active disease. We also identified an important sub-group of TB patients who harbour isolates with matching patterns. Depending on the matching criterion used we attributed between 6% (95% CI: 4, 9%) and 22% (95% CI: 18, 27%) of TB cases to recent transmission; the vast majority of active TB disease reflects infection acquired at an earlier time and/or a different place. However, Haitian-born TB patients yielded a disproportionately high frequency of isolates belonging to matching "clusters" (21%; 95% CI: 13, 32%), while, other foreign-born patients have disproportionately low numbers of clustered isolates (5%; 95% CI: 3, 9%). / The classical interpretation of such results is that there is more ongoing transmission within this immigrant sub-group. We explored an alternative hypothesis: that M. tuberculosis isolates from Haitian-born patients demonstrate reduced genetic diversity reflecting TB transmission patterns in their previously isolated country of origin---hence that a bacterial founder effect accounts for the higher frequency of matching fingerprints. Using a recently introduced measure of fingerprint similarity, genetic distance, we assessed the extent of pattern diversity. The median nearest genetic distance (NGD) was 130 months (inter-quartile range (IQR): 98--201 months) among the 47 distinct isolates from Haitian-born patients; among the non-Haitian foreign-born, the median NGD for the 191 distinct isolates was 128 months (IQR: 103--170 months). Hence the overall genetic heterogeneity of M. tuberculosis organisms among Haitian-born Montrealers was as great as that among a group of patients born in 70 other countries. Local transmission among the Haitian-born remains the most likely scenario. / We demonstrated that a continuous measure, such as genetic distance, may also permit researchers to address a challenge to the interpretation of M. tuberculosis molecular typing results: how to determine whether highly similar, non-identical fingerprint patterns in fact reflect underlying "matches." The distribution of NGD for isolates initially classified as identical (10--27 months), similar (15--108 months) and unique (40--244 months) suggested a possible cut-point of 40 months. Use of this cut-point labelled 19% of isolates as "clustered", suggesting that 14% of Montreal TB cases reflected transmission during the study period.

Thesis (Ph.D.)--Pacific Graduate School of Psychology, 1997. / Source: Dissertation Abstracts International, Volume: 59-07, Section: B, page: 3682. Chair: Christine Zalewski.

Thesis (Ph.D.)--Indiana University, School of Library and Information Science, 2006. / "Title from dissertation home page (viewed July 10, 2007)." Source: Dissertation Abstracts International, Volume: 67-08, Section: A, page: 2796. Adviser: Javed Mostafa.

Mutations in the ATRX gene are responsible for the alpha-thalassemia mental retardation (ATR-X) syndrome. ATRX is a putative global transcription regulator and chromatin remodelling protein. The goal of this research is to characterize interactions ATRX has with other proteins involved in transcription regulation, and identify domains in ATRX that may be responsible for these interactions. Several stable NIH 3T3 tet-off cell lines have been established that contain a human ATRX transgene. In addition, ATRX, PML, and Daxx appear to co-localize in nuclear bundles, suggesting they may act together transiently, or in a complex, in a regulatory role. A domain has been identified on ATRX that appears to target the protein to nuclear bundles, and interact with PML and Daxx. ATRX patient mutations appear to alter these interactions. This work attempts to elucidate cellular functions of ATRX, in hopes of establishing a better understanding of the neuropathology of this complex disease.

Herpesviruses are highly prevalent human pathogens that have the ability to form life-long latent infection in host cells. The persistent reinjury of vessels upon virus reactivation has been suggested to link infection to vascular disease. The goal of this study was to determine the mechanism and role of early initiating events in virus-mediated vasculopathy. We now report that these events are mediated through the expression of tissue factor (TF) and a previously unknown mechanism, that both function in the acceleration of factor VIIa (FVIIa)-dependent activation of factor X (FX) to FXa. The current study identifies herpes simplex virus type 1 (HSV1)-encoded glycoprotein C (gC) as a novel second independent FX activating pathway on the virus surface. Using specific chromogenic assays, an HSV1 gC-deficient virus invariably generated 5 fold less FXa per particle than either wild type or gC-rescued strains. The direct involvement of gC was confirmed using purified recombinant gC, which enhanced FXa production, and like TF, was dependent on FVIIa, Ca 2+ and anionic phospholipid. Differential inhibition of gC-competent and -deficient strains by an anti-TF antibody confirmed simultaneous and independent TF- and gC-dependent FX activating mechanisms on the virus. Hypothesizing that cell signaling by thrombin, the final coagulation protease, may be advantageous to the virus, the effect on Herpesvirus infection was assessed. Using plaque formation assays, a thrombin specific inhibitor, hirudin, was shown to attenuate the serum-dependent increase in infection, demonstrating the importance of virus initiated thrombin production. In agreement, the addition of purified thrombin resulted in an approximate 60--80% increase in infectious events. The same enhancement was facilitated by incubation with a protease activated receptor 1 (PAR1) agonist, TRAP, indicating the effect is mediated through at least PAR1 on the cell surface. Using western blot analysis and chromogenic assays, individual variations in thrombogenic potential associated with each Herpesvirus was also determined and correlated with well-documented clinical observations. Cumulatively, these observations illustrate that Herpesviruses have evolved strategies to mimic and exploit host proteins to generate haemostatic cell signaling enzymes that may ultimately lead to the increased susceptibility of cells to infection and perturbation of the vasculature.