PvDBPII elicits multiple antibody-mediated mechanisms that reduce growth in a Plasmodium vivax challenge trial

The receptor-binding domain, region II, of the Plasmodium vivax Duffy binding protein (PvDBPII) binds the Duffy antigen on the reticulocyte surface to mediate invasion. A heterologous vaccine challenge trial recently showed that a delayed dosing regimen with recombinant PvDBPII SalI variant formulated with adjuvant Matrix-MTM reduced the in vivo parasite multiplication rate (PMR) in immunized volunteers challenged with the Thai P. vivax isolate PvW1. Here, we describe extensive analysis of the polyfunctional antibody responses elicited by PvDBPII immunization and identify immune correlates for PMR reduction. A classification algorithm identified antibody features that significantly contribute to PMR reduction. These included antibody titre, receptor-binding inhibitory titre, dissociation constant of the PvDBPII-antibody interaction, complement C1q and Fc gamma receptor binding and specific IgG subclasses. These data suggest that multiple immune mechanisms elicited by PvDBPII immunization are likely to be associated with protection and the immune correlates identified could guide the development of an effective vaccine for P. vivax malaria. Importantly, all the polyfunctional antibody features that correlated with protection cross-reacted with both PvDBPII SalI and PvW1 variants, suggesting that immunization with PvDBPII should protect against diverse P. vivax isolates.

Unveiling P. vivax invasion pathways in Duffy-negative individuals

Vivax malaria has long been thought to be absent from sub-Saharan Africa owing to the high proportion of individuals lacking the Duffy antigen receptor for chemokines (DARC) in their erythrocytes. The interaction between P. vivax Duffy-binding protein (PvDBP) and DARC is assumed to be the main pathway used by merozoites to invade reticulocytes. However, the increasing number of reports of vivax malaria cases in genotypically Duffy-negative (DN) individuals has raised questions regarding the P. vivax invasion pathway(s). Here, we show that a subset of DN erythroblasts transiently express DARC during terminal erythroid differentiation and that P. vivax merozoites, irrespective of their origin, can invade DARC+ DN erythroblasts. These findings reveal that a large number of DN individuals may represent a silent reservoir of deep P. vivax infections at the sites of active erythropoiesis with low or no parasitemia, and it may represent an underestimated biological problem with potential clinical consequences in sub-Saharan Africa.

Culture and language coaching for bilingual residents: the first 10 years of the CHiCoS model

ProblemIn the US, there are neither professional standards nor adequate formal training opportunities related to physician use of non-English languages, the most common of which is Spanish. To achieve safe, effective health care for culturally and linguistically diverse patients, the medical profession needs clear standards for physician language use and proven culture and language training models that include validated assessment of linguistic proficiency. InterventionThe authors describe the first decade of an innovative culture and language coaching program for bilingual (Spanish-English) pediatric residents, including the model's evolution and outcomes, as well as recommendations for implementing similar programs elsewhere. Over 10 years, the model has grown from a central innovation-the professional culture and language coach (CLC). The CLC provides 1:1 in-visit support and post-visit coaching to individual residents during three years of continuity clinic experience in a Spanish-language setting (Clínica Hispana de Cuidados de Salud-CHiCoS). They also provide a range of supplementary learning activities (e.g., simulations, immersion rotations, mock testing) and periodic formal assessment of language proficiency. Foundational program elements include cultural and linguistic humility, variations in language, pragmatic linguistics and trans-languaging, the inseparability of culture and language, health literacy, and a flat teaching hierarchy ("all teach, all learn"). ContextCHiCoS has been implemented continuously since 2009 in the primary care clinic of a stand-alone academic pediatric hospital in the Midwest, where pediatric residents have their continuity clinic experience over three years of residency. ImpactFifty-six residents have participated, reporting improved language skills, cultural knowledge, and ability to care for Spanish-speaking patients. Sixty-eight percent of residents not qualified bilingual upon program entry passed a validated physician language assessment by graduation. Spanish-speaking patients seen by CHiCoS residents and faculty reported higher satisfaction, trust, and communication scores than those seen in non-bilingual areas of the same clinic (p < .05 for all scores). The program increased bilingual faculty six-fold and changed attitudes and practices related to language supports throughout the residency program. Lessons LearnedCulture and language coaching provides effective preparation and assessment of bilingual physicians, leading to improved care for culturally and linguistically diverse patients. Our model offers an example for developing similar approaches for a variety of clinicians throughout health care. Such approaches should include professional standards for non-English language use, training supports customized to bilingual learners' proficiency levels, and a focus on integrating practical cultural and linguistic skills to achieve safe, effective clinical communication.

Immunogenicity of a Plasmodium vivax vaccine based on the duffy binding protein formulated using adjuvants compatible for use in humans

The invasion of reticulocytes by Plasmodium vivax merozoites is dependent on the interaction of the Plasmodium vivax Duffy Binding Protein (PvDBP) with the Duffy antigen receptor for chemokines (DARC). The N-terminal cysteine-rich region II of PvDBP (PvDBPII), which binds DARC, is a leading P. vivax malaria vaccine candidate. Here, we have evaluated the immunogenicity of recombinant PvDBPII formulated with the adjuvants Matrix-M and GLA-SE in mice. Analysis of the antibody responses revealed comparable ELISA recognition titres as well as similar recognition of native PvDBP in P. vivax schizonts by immunofluorescence assay. Moreover, antibodies elicited by the two adjuvant formulations had similar functional properties such as avidity, isotype profile and inhibition of PvDBPII-DARC binding. Furthermore, the anti-PvDBPII antibodies were able to block the interaction of DARC with the homologous PvDBPII SalI allele as well as the heterologous PvDBPII PvW1 allele from a Thai clinical isolate that is used for controlled human malaria infections (CHMI). The cross-reactivity of these antibodies with PvW1 suggest that immunization with the PvDBPII SalI strain should neutralize reticulocyte invasion by the challenge P. vivax strain PvW1.

Vaccination with Plasmodium vivax Duffy-binding protein inhibits parasite growth during controlled human malaria infection

There are no licensed vaccines against Plasmodium vivax. We conducted two phase 1/2a clinical trials to assess two vaccines targeting P. vivax Duffy-binding protein region II (PvDBPII). Recombinant viral vaccines using chimpanzee adenovirus 63 (ChAd63) and modified vaccinia virus Ankara (MVA) vectors as well as a protein and adjuvant formulation (PvDBPII/Matrix-M) were tested in both a standard and a delayed dosing regimen. Volunteers underwent controlled human malaria infection (CHMI) after their last vaccination, alongside unvaccinated controls. Efficacy was assessed by comparisons of parasite multiplication rates in the blood. PvDBPII/Matrix-M, given in a delayed dosing regimen, elicited the highest antibody responses and reduced the mean parasite multiplication rate after CHMI by 51% (n = 6) compared with unvaccinated controls (n = 13), whereas no other vaccine or regimen affected parasite growth. Both viral-vectored and protein vaccines were well tolerated and elicited expected, short-lived adverse events. Together, these results support further clinical evaluation of the PvDBPII/Matrix-M P. vivax vaccine.

Impact of a blood-stage vaccine on Plasmodium vivax malaria

Background

There are no licensed vaccines against Plasmodium vivax , the most common cause of malaria outside of Africa.

Methods

We conducted two Phase I/IIa clinical trials to assess the safety, immunogenicity and efficacy of two vaccines targeting region II of P. vivax Duffy-binding protein (PvDBPII). Recombinant viral vaccines (using ChAd63 and MVA vectors) were administered at 0, 2 months or in a delayed dosing regimen (0, 17, 19 months), whilst a protein/adjuvant formulation (PvDBPII/Matrix-M™) was administered monthly (0, 1, 2 months) or in a delayed dosing regimen (0, 1, 14 months). Delayed regimens were due to trial halts during the COVID-19 pandemic. Volunteers underwent heterologous controlled human malaria infection (CHMI) with blood-stage P. vivax parasites at 2-4 weeks following their last vaccination, alongside unvaccinated controls. Efficacy was assessed by comparison of parasite multiplication rate (PMR) in blood post-CHMI, modelled from parasitemia measured by quantitative polymerase-chain-reaction (qPCR).

Results

Thirty-two volunteers were enrolled and vaccinated (n=16 for each vaccine). No safety concerns were identified. PvDBPII/Matrix-M™, given in the delayed dosing regimen, elicited the highest antibody responses and reduced the mean PMR following CHMI by 51% (range 36-66%; n=6) compared to unvaccinated controls (n=13). No other vaccine or regimen impacted parasite growth. In vivo growth inhibition of blood-stage P. vivax correlated with functional antibody readouts of vaccine immunogenicity.

Conclusions

Vaccination of malaria-naïve adults with a delayed booster regimen of PvDBPII/ Matrix-M™ significantly reduces the growth of blood-stage P. vivax . Funded by the European Commission and Wellcome Trust; VAC069, VAC071 and VAC079 ClinicalTrials.gov numbers NCT03797989 , NCT04009096 and NCT04201431 .

Cultural Health Beliefs and Practices Among Hispanic Parents

Parents' beliefs about and approaches to their child's health vary with culture and change within cultures over time. To provide an updated understanding of folk and traditional medicine (FTM) among Hispanic parents in the United States, we surveyed 200 caregivers identifying their child as Hispanic in a pediatric primary care clinic about their cultural health beliefs and practices. Overall, 84% of participants believed in ≥1 folk illness, with foreign-born participants more likely than US-born to endorse folk illness beliefs. Eighty-three percent had used cultural remedies for their children. Of those, although just 15% had discussed such practices with their child's provider, 86% would feel comfortable doing so. No demographic factors predicted use of cultural remedies/healers or comfort talking to providers. Beliefs and practices related to FTM are prevalent among Hispanic parents and cannot be predicted using demographics; providers should routinely ask all families about FTM.

Asymmetric distribution of dynamin-2 and β-catenin relative to tight junction spikes in alveolar epithelial cells

Tight junctions between lung alveolar epithelial cells maintain an air-liquid barrier necessary for healthy lung function. Previously, we found that rearrangement of tight junctions from a linear, cortical orientation into perpendicular protrusions (tight junction spikes) is associated with a decrease in alveolar barrier function, especially in alcoholic lung syndrome. Using quantitative super-resolution microscopy, we found that spikes in control cells were enriched for claudin-18 as compared with alcohol-exposed cells. Moreover, using an in situ method to measure barrier function, tight junction spikes were not associated with localized increases in permeability. This suggests that tight junction spikes have a regulatory role as opposed to causing a physical weakening of the epithelial barrier. We found that tight junction spikes form at cell-cell junctions oriented away from pools of β-catenin associated with actin filaments, suggesting that adherens junctions determine the directionality of tight junction spikes. Dynamin-2 was associated with junctional claudin-18 and ZO-1, but showed little localization with β-catenin and tight junction spikes. Treatment with Dynasore decreased the number of tight junction spikes/cell, increased tight junction spike length, and stimulated actin to redistribute to cortical tight junctions. By contrast, Dynole 34-2 and MiTMAB altered β-catenin localization, and reduced tight junction spike length. These data suggest a novel role for dynamin-2 in tight junction spike formation by reorienting junction-associated actin. Moreover, the greater spatial separation of adherens and tight junctions in squamous alveolar epithelial cells as compared with columnar epithelial cells facilitates analysis of molecular regulation of the apical junctional complex.

Advances in multimodal data fusion in neuroimaging: Overview, challenges, and novel orientation

Multimodal fusion in neuroimaging combines data from multiple imaging modalities to overcome the fundamental limitations of individual modalities. Neuroimaging fusion can achieve higher temporal and spatial resolution, enhance contrast, correct imaging distortions, and bridge physiological and cognitive information. In this study, we analyzed over 450 references from PubMed, Google Scholar, IEEE, ScienceDirect, Web of Science, and various sources published from 1978 to 2020. We provide a review that encompasses (1) an overview of current challenges in multimodal fusion (2) the current medical applications of fusion for specific neurological diseases, (3) strengths and limitations of available imaging modalities, (4) fundamental fusion rules, (5) fusion quality assessment methods, and (6) the applications of fusion for atlas-based segmentation and quantification. Overall, multimodal fusion shows significant benefits in clinical diagnosis and neuroscience research. Widespread education and further research amongst engineers, researchers and clinicians will benefit the field of multimodal neuroimaging.

Advances in smart roads for future smart cities

Various countries throughout the world have started their efforts in designing and implementing smart cities. China alone has over 300 smart city projects, with strong participation by industries and government offices. India too have allocated trillions in budget to build over 100 smart cities. An essential part of a smart city is transport. In this paper, we will discuss the current state, developments, and some of the emerging advances in transportation technologies and how these advances in smart roads will prepare the society towards the realization of future smart cities.

Biliary tract cancers: systemic therapy for advanced disease

Biliary tract carcinomas (BTC) present with minimal symptoms and thus they are often diagnosed in advanced stages that require systemic therapy. Unfortunately, if not resected, BTC's prognosis is generally poor, in part due to limited therapeutic options. Herein we will highlight the various systemic therapies that have proven efficacy in these diseases in both 1st and 2nd line. As it stands now, the combination of Gemcitabine and Cisplatin is the gold standard. Gemcitabine plus Cisplatin (Gem-Cis)-nab-paclitaxel showed improved survival in a phase II trial compared with historical controls. SWOG 1815 is a phase III trial currently underway comparing Gem-Cis-nab-paclitaxel to Gem-Cis and if positive, this has the potential to establish a new standard of care. New data from the ABC-06 study has shown a survival benefit using FOLFOX in the 2nd line setting. Molecularly targeted agents in BTC have demonstrated potential beyond Gem-Cis and while currently limited to second- and later-line therapies, ongoing trials are testing their efficacy even in newly diagnosed patients. With both incremental improvements in existing therapies and the development of entirely novel agents, the future of systemic therapy for BTC is promising.

Analysis of clinical diagnosis for all patients receiving antenatal betamethasone in a community hospital

OBJECTIVE

Identify which obstetrical diagnoses are associated with suboptimal antenatal betamethasone administration.

METHODS

We present a retrospective, cohort study of patients who received betamethasone due to a risk for preterm delivery, between 7/2013 and 9/2016 at our institution. Details of betamethasone administration were recorded including the diagnosis leading to betamethasone. Optimal administration was defined as two doses of betamethasone given 24 hours apart, with delivery occurring at greater than 24 hours but less than seven days after completion of the second dose of betamethasone. Suboptimal administration included any betamethasone dosing that did not meet the optimal criteria.

RESULTS

428 patients were identified for the study with 20.1% of patients receiving optimal betamethasone. Patients presenting with hypertensive disorders of pregnancy (36.1%) and preterm premature rupture of membranes (PPROM) (22.1%) were more likely to receive optimal betamethasone, while patients presenting with preterm labor (PTL) (41.8%) and placental abruption (24.6%) were more likely to receive suboptimal betamethasone (p-value < 0.0001). Among PTL patients, those presenting with contractions and cervical dilation/short cervix (19.15%) were more likely to receive optimal betamethasone (p-value 0.0349). Optimal betamethasone decreased the incidence of respiratory distress syndrome (RDS) among 32.1 to 34 week neonates.

CONCLUSION

Hypertensive disorders of pregnancy and PPROM are associated with optimal betamethasone, whereas PTL and placental abruption are associated with suboptimal betamethasone.

Sensing Traffic Density Combining V2V and V2I Wireless Communications

Wireless technologies are making the development of new applications and services in vehicular environments possible since they enable mobile communication between vehicles (V2V), as well as communication between vehicles and infrastructure nodes (V2I). Usually, V2V communications are dedicated to the transmission of small messages mainly focused on improving traffic safety. Instead, V2I communications allow users to access the Internet and benefit from higher level applications. The combination of both V2V and V2I, known as V2X communications, can increase the benefits even further, thereby making intelligent transportation systems (ITS) a reality. In this paper, we introduce V2X-d, a novel architecture specially designed to estimate traffic density on the road. In particular, V2X-d exploits the combination of V2V and V2I communications. Our approach is based on the information gathered by sensors (i.e., vehicles and road side units (RSUs)) and the characteristics of the roadmap topology to accurately make an estimation of the instant vehicle density. The combination of both mechanisms improves the accuracy and coverage area of the data gathered, while increasing the robustness and fault tolerance of the overall approach, e.g., using the information offered by V2V communications to provide additional density information in areas where RSUs are scarce or malfunctioning. By using our collaborative sensing scheme, future ITS solutions will be able to establish adequate dissemination protocols or to apply more efficient traffic congestion reduction policies, since they will be aware of the instantaneous density of vehicles.

Mechanisms of resistance to cabazitaxel

We studied mechanisms of resistance to the novel taxane cabazitaxel in established cellular models of taxane resistance. We also developed cabazitaxel-resistant variants from MCF-7 breast cancer cells by stepwise selection in drug alone (MCF-7/CTAX) or drug plus the transport inhibitor PSC-833 (MCF-7/CTAX-P). Among multidrug-resistant (MDR) variants, cabazitaxel was relatively less cross-resistant than paclitaxel and docetaxel (15- vs. 200-fold in MES-SA/Dx5 and 9- vs. 60-fold in MCF-7/TxT50, respectively). MCF-7/TxTP50 cells that were negative for MDR but had 9-fold resistance to paclitaxel were also 9-fold resistant to cabazitaxel. Selection with cabazitaxel alone (MCF-7/CTAX) yielded 33-fold resistance to cabazitaxel, 52-fold resistance to paclitaxel, activation of ABCB1, and 3-fold residual resistance to cabazitaxel with MDR inhibition. The MCF-7/CTAX-P variant did not express ABCB1, nor did it efflux rhodamine-123, BODIPY-labeled paclitaxel, and [(3)H]-docetaxel. These cells are hypersensitive to depolymerizing agents (vinca alkaloids and colchicine), have reduced baseline levels of stabilized microtubules, and impaired tubulin polymerization in response to taxanes (cabazitaxel or docetaxel) relative to MCF-7 parental cells. Class III β-tubulin (TUBB3) RNA and protein were elevated in both MCF-7/CTAX and MCF-7/CTAX-P. Decreased BRCA1 and altered epithelial-mesenchymal transition (EMT) markers are also associated with cabazitaxel resistance in these MCF-7 variants, and may serve as predictive biomarkers for its activity in the clinical setting. In summary, cabazitaxel resistance mechanisms include MDR (although at a lower level than paclitaxel and docetaxel), and alterations in microtubule dynamicity, as manifested by higher expression of TUBB3, decreased BRCA1, and by the induction of EMT.

Abstract 763: Resistance to cabazitaxel is associated with ABCB1/P-glycoprotein activation, alterations in β-tubulin content and dynamics, reduced BRCA1, and a mesenchymal phenotype in MCF-7 human breast cancer variants

In order to identify determinants of cellular response to this new taxane, we derived a resistant variant from the MCF-7 human breast cancer cell line by stepwise selection in cabazitaxel. The 33-fold resistance to cabazitaxel in this variant, MCF-7/CTAX, was associated with ABCB1/P-glycoprotein (P-gp) activation, but also 3-fold residual resistance to taxanes after modulation with the P-gp inhibitor PSC-833, 2 μM. Another variant was established by co-selecting in the presence of PSC-833 (MCF-7/CTAX-P). This variant was negative for ABCB1 transcripts and accumulated parental levels of rhodamine-123, BODIPY-labeled paclitaxel and [3H]-docetaxel, indicating that the taxane resistance (9-fold) observed in this cell line is not mediated by transporters. However, we observed a 34% reduction in bound fluorescent-labeled paclitaxel in MCF-7/CTAX-P relative to parental controls by flow cytometry. These cells are hypersensitive to depolymerizing agents (vincas and colchicine) indicating a change in tubulin dynamic instability, and we observed reduced baseline tubulin polymer in untreated MCF-7/CTAX-P cells, and impaired tubulin polymerization in response to taxane exposure (cabazitaxel or docetaxel) relative to MCF-7 parental cells. Quantitative PCR and immunoblotting confirmed elevated levels of the class III (TUBB3) β-tubulin isotype in both MCF-7/CTAX and MCF-7/CTAX-P. Reduced BRCA1 content was observed in both MCF-7 variants, which could affect taxane response via the regulation of the mitotic spindle checkpoint. Gene silencing with specific siRNAs confirmed that reduced TUBB3 sensitizes cells to cabazitaxel, and reduced BRCA1 results in taxane resistance. In addition, altered epithelial-mesenchymal transition markers (elevated Vimentin, reduced E-cadherin) are associated with cabazitaxel resistance in these MCF-7 variants. In summary, cabazitaxel resistance mechanisms include MDR (although at a lower level than paclitaxel and docetaxel), and alterations in microtubule dynamicity, as manifested by higher expression of TUBB3, decreased BRCA1, and by the induction of EMT.

Citation Format: George E. Duran, Yan C. Wang, E Brian Francisco, Francisco J. Martinez, Branimir I. Sikic. Resistance to cabazitaxel is associated with ABCB1/P-glycoprotein activation, alterations in β-tubulin content and dynamics, reduced BRCA1, and a mesenchymal phenotype in MCF-7 human breast cancer variants. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 763. doi:10.1158/1538-7445.AM2014-763

Identifying the key factors affecting warning message dissemination in VANET real urban scenarios

In recent years, new architectures and technologies have been proposed for Vehicular Ad Hoc networks (VANETs). Due to the cost and complexity of deploying such networks, most of these proposals rely on simulation. However, we find that most of the experiments made to validate these proposals tend to overlook the most important and representative factors. Moreover, the scenarios simulated tend to be very simplistic (highways or Manhattan-based layouts), which could seriously affect the validity of the obtained results. In this paper, we present a statistical analysis based on the 2^k factorial methodology to determine the most representative factors affecting traffic safety applications under real roadmaps. Our purpose is to determine which are the key factors affecting Warning Message Dissemination in order to concentrate research tests on such parameters, thus avoiding unnecessary simulations and reducing the amount of simulation time required. Simulation results show that the key factors affecting warning messages delivery are the density of vehicles and the roadmap used. Based on this statistical analysis, we consider that VANET researchers must evaluate the benefits of their proposals using different vehicle densities and city scenarios, to obtain a broad perspective on the effectiveness of their solution. Finally, since city maps can be quite heterogeneous, we propose a roadmap profile classification to further reduce the number of cities evaluated.

Abstract 901: Overexpression of inhibitors of apoptosis (IAP) family members in human breast and ovarian cancer models of non-MDR1 taxane resistance

Four breast cancer cell lines (MCF-7, BT-549, MDA-MB-231 and T-47D) and four ovarian cancer cell lines (1A9/A2780, ES-2, MES-OV and OVCAR-3) were selected for taxane resistance by exposing cells to either docetaxel or paclitaxel in the presence of the P-glycoprotein inhibitor, PSC-833 (valspodar, 2 μM). All of these co-selected variants are MDR1/ABCB1(-), and the resistance to taxanes is not transporter-mediated. We have previously reported elevated class III β-tubulin (TUBB3), reduced BRCA1, elevated CDKN1A (p21), and altered epithelial-mesenchymal transition (EMT) genes in the majority of the non-MDR1 taxane variants. Inhibitors of apoptosis (IAP) proteins directly bind and inhibit several caspases, and may play a critical role in determining cell fate after exposure to chemotherapeutic agents. In this study, we profiled the expression of IAP proteins and found elevated content in this panel of taxane-resistant human breast and ovarian cancer cell lines. In both the paclitaxel- (TP) and docetaxel-selected (TxTP) ovarian cancer cell lines we observed significantly overexpressed cIAP1 (BIRC2), cIAP2 (BIRC3), XIAP (BIRC4), and Livin (BIRC7) relative to parental cell lines. Expression of cIAP2 was undetectable in OVCAR-3 and its taxane resistant cell lines, OVCAR-3/TP20 and OVCAR-3/TxTP5. Elevated cIAP1 and XIAP levels were detected in the human breast cancer variant BT-549/TxTP50, and Livin was overexpressed in all taxane-resistant breast cancer cell models. Survivin (BIRC5) is highly expressed in cancers and has been associated with taxane resistance via its effects on apoptosis and the cell cycle. We observed reduced Survivin content in the majority of the variants established in our laboratory except for the ovarian ES-2/TP80 cell line where we found slightly elevated expression resulting from paclitaxel selection relative to its parental control. In addition to these alterations in IAP content, we observed elevated Bcl-2 in ovarian (MES-OV/TP40 and MES-OV/TxTP50) and breast (MCF-7/TxTP50, BT-549/TxTP50, and MDA231/TxTP50) cancer cell lines at the transcript level by rt-PCR and confirmed by immunoblotting. Specific gene silencing by RNAi and treatment with small molecule inhibitors will test the functional significance of IAP alterations in these models of taxane resistance.

Citation Format: George E. Duran, Anamaria Brozovic, Francisco J. Martinez, E Brian Francisco, Yan C. Wang, Branimir I. Sikic. Overexpression of inhibitors of apoptosis (IAP) family members in human breast and ovarian cancer models of non-MDR1 taxane resistance. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 901. doi:10.1158/1538-7445.AM2013-901

An infrastructureless approach to estimate vehicular density in urban environments

In Vehicular Networks, communication success usually depends on the density of vehicles, since a higher density allows having shorter and more reliable wireless links. Thus, knowing the density of vehicles in a vehicular communications environment is important, as better opportunities for wireless communication can show up. However, vehicle density is highly variable in time and space. This paper deals with the importance of predicting the density of vehicles in vehicular environments to take decisions for enhancing the dissemination of warning messages between vehicles. We propose a novel mechanism to estimate the vehicular density in urban environments. Our mechanism uses as input parameters the number of beacons received per vehicle, and the topological characteristics of the environment where the vehicles are located. Simulation results indicate that, unlike previous proposals solely based on the number of beacons received, our approach is able to accurately estimate the vehicular density, and therefore it could support more efficient dissemination protocols for vehicular environments, as well as improve previously proposed schemes.

Pulmonary function measures predict mortality differently in IPF versus combined pulmonary fibrosis and emphysema

The composite physiologic index (CPI) was derived to represent the extent of fibrosis on high-resolution computed tomography (HRCT), adjusting for emphysema in patients with idiopathic pulmonary fibrosis (IPF). We hypothesised that longitudinal change in CPI would better predict mortality than forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC) or diffusing capacity of the lung for carbon monoxide (D(L,CO)) in all patients with IPF, and especially in those with combined pulmonary fibrosis and emphysema (CPFE). Cox proportional hazard models were performed on pulmonary function data from IPF patients at baseline (n = 321), 6 months (n = 211) and 12 months (n = 144). Presence of CPFE was determined by HRCT. A five-point increase in CPI over 12 months predicted subsequent mortality (HR 2.1, p = 0.004). At 12 months, a 10% relative decline in FVC, a 15% relative decline in D(L,CO) or an absolute increase in CPI of five points all discriminated median survival by 2.1 to 2.2 yrs versus patients with lesser change. Half our cohort had CPFE. In patients with moderate/severe emphysema, only a 10% decline in FEV(1) predicted mortality (HR 3.7, p = 0.046). In IPF, a five-point increase in CPI over 12 months predicts mortality similarly to relative declines of 10% in FVC or 15% in D(L,CO). For CPFE patients, change in FEV(1) was the best predictor of mortality.

Prevalence and clinical correlates of bronchoreversibility in severe emphysema

Chronic obstructive pulmonary disease (COPD) exhibits airflow obstruction that is not fully reversible. The importance of bronchoreversibility remains controversial. We hypothesised that an emphysematous phenotype of COPD would be associated with decreased bronchoreversibility. 544 patients randomised to the medical arm of the National Emphysema Treatment Trial formed the study group. Participants underwent multiple measurements of bronchoreversibility on a mean of four sessions over 1.91 yrs. They were also characterised by measures of symptoms, quality of life and quantitative measures of emphysema by computed tomography. Mean baseline forced expiratory volume in 1 s (FEV(1)) in this patient population is 24% predicted. 22.2% of patients demonstrated bronchoreversibility on one or more occasions using American Thoracic Society/European Respiratory Society criteria. Few patients (0.37%) had bronchoreversibility on all completed tests. Patients who demonstrated bronchoreversibility were more likely to be male, and have better lung function and less emphysema. 64% of patients demonstrated large (> or =400 mL) changes in forced vital capacity (FVC). In a severe emphysema population, bronchoreversibility as defined by change in FEV(1) is infrequent, varies over time, and is more common in males and those with less severe emphysema. Improvements in FVC, however, were demonstrated in the majority of patients.

TLR9 is expressed in idiopathic interstitial pneumonia and its activation promotes in vitro myofibroblast differentiation

Infectious diseases can be cofactors in idiopathic interstitial pneumonias (IIP) pathogenesis; recent data suggests that toll-like receptors 9 (TLR9) ligands contribute to experimental chronic tissue remodeling. Real-time TAQMAN and immunohistochemical analysis of IIP normal surgical lung biopsies (SLBs), primary fibroblast lines grown from both IIP and normal SLBs indicate that TLR9 is prominently and differentially expressed in a disease-specific manner. TLR9 expression was increased in biopsies from patients with IIP compared with normal lung biopsies and its expression is localized to areas of marked interstitial fibrosis. TLR9 in fibroblasts appeared to be increased by profibrotic Th2 cytokines (IL-4 and IL-13) and this was true in fibroblasts cultured from the most severe form of IIP, idiopathic pulmonary fibrosis (IPF) SLBs, in non-specific interstitial pneumonia fibroblast lines, and in normal fibroblasts. Finally, confocal microscopy studies have shown that TLR9 activation by its synthetic agonist CpG-ODN significantly increased the expression of alpha smooth muscle actin, the main marker of myofibroblast differentiation. These data indicate that TLR9 expression may drive the abnormal tissue healing response in severe forms of IIP and its activation can have a key role in myofibroblast differentiation promoting the progression of disease during the terminal phase of IPF.

Outcomes for COPD pharmacological trials: from lung function to biomarkers

The American Thoracic Society/European Respiratory Society jointly created a Task Force on "Outcomes for COPD pharmacological trials: from lung function to biomarkers" to inform the chronic obstructive pulmonary disease research community about the possible use and limitations of current outcomes and markers when evaluating the impact of a pharmacological therapy. Based on their review of the published literature, the following document has been prepared with individual sections that address specific outcomes and markers, and a final section that summarises their recommendations.

Sex differences in physiological progression of idiopathic pulmonary fibrosis

In idiopathic pulmonary fibrosis, incidence is higher in males, and females may have better survival. The aim of the present study was to determine whether the rate of increase in desaturation during serial 6-min walk testing would be greater, and survival worse, for males versus females. Serial changes in the percentage of maximum desaturation area (DA) over 1 yr were estimated using mixed models in 215 patients. DA was defined as the total area above the curve created using desaturation percentage values observed during each minute of the 6-min walk test. Multivariate Cox regression assessed survival differences. Adjusting for baseline DA, 6-min walk distance, change in 6-min walk distance over time and smoking history, the percentage of maximum DA increased by an average of 2.83 and 1.37% per month for males and females, respectively. Females demonstrated better survival overall, which was more pronounced in patients who did not desaturate below 88% on ambulation at baseline and after additionally adjusting for 6-month relative changes in DA and forced vital capacity. These data suggest that differences in disease progression contribute to, but do not completely explain, better survival of females with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis fibroblasts migrate and proliferate to CC chemokine ligand 21

Idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia (UIP) is the severest form of idiopathic interstitial pneumonia for which therapeutic targets are needed. Surgical lung biopsy specimens from IPF/UIP patients exhibit focal expression of CC chemokine receptor (CCR) 7, but the identity of these CCR7-positive cells is unknown. The purpose of the present study was to examine the functional and signalling significance of CCR7 expression of primary fibroblasts grown from IPF/UIP and normal surgical lung biopsy specimens. Primary fibroblasts were cultured from surgical lung biopsy specimens from IPF/UIP and normal patients. Fibroblasts treated with or without CC chemokine ligand (CCL) 21 were analysed for functional, transcriptional and proteomic differences using immunocytochemical analysis, gene arrays, Taqman real-time PCR, and migration, proliferation and Western blot assays. CCR7 was expressed by IPF/UIP fibroblasts, but not normal fibroblasts. IPF/UIP fibroblasts, but not normal fibroblasts, showed significant migratory and proliferative responses when exposed to CCL21, which were inhibited by pertussis toxin or neutralising antibodies to CCR7. Exposure of IPF/UIP fibroblasts to CCL21 altered the phosphorylation status of mitogen-activated protein kinase kinase 1/2, extracellular signal-regulated kinase 1/2 and ribosomal S6 kinase (90 kDa) in these cells; this was abrogated by pertussis toxin or CCR7-specific small interfering RNA. Together, these data demonstrate that CC chemokine ligand 21 modulates the functional properties of idiopathic pulmonary fibrosis/usual interstitial pneumonia fibroblasts, but not normal fibroblasts.

Changes in periodontal health status are associated with bacterial community shifts as assessed by quantitative 16S cloning and sequencing

The gingival sulcus contains a complex ecosystem that includes many uncultivated bacteria. Understanding the dynamics of this ecosystem in transitions between health and disease is important in advancing our understanding of the bacterial etiology of periodontitis. The objective of this longitudinal study was to examine the stability of bacterial colonization in the gingival crevice and to explore the relationship between shifts in microbial composition and changes in periodontal health status using a comprehensive, quantitative, culture-independent approach. Subgingival plaque samples and periodontal data were collected from 24 subjects over 2 years. Baseline and 2-year plaque samples were analyzed using quantitative ribosomal 16S cloning and sequencing. Ten subjects remained periodontally healthy over 2 years, the periodontal health of seven subjects worsened, and seven subjects showed clinical improvement. Bacterial stability was greatest among healthy, clinically stable subjects and lowest for subjects whose periodontal status worsened (P = 0.01). Higher numbers of species lost or gained were also observed for subjects whose clinical status changed (P = 0.009). This provides evidence that a change in periodontal status is accompanied by shifts within the bacterial community. Based on these data, measures of microbial stability may be useful in clinical diagnosis and prognosis. Regarding individual species, increases in levels of the uncultivated phylotype Veillonella sp. oral clone X042, a gram-negative bacterium and the most common member of the subgingival bacterial community, were associated with periodontal health (P = 0.04), suggesting that this is an important beneficial species. Filifactor alocis, a gram-positive anaerobe, was found at higher levels in subjects with disease (P = 0.01).

Focal interstitial CC chemokine receptor 7 (CCR7) expression in idiopathic interstitial pneumonia

BACKGROUND/AIMS

Idiopathic interstitial pneumonias (IIPs) are a diverse grouping of chronic pulmonary diseases characterised by varying degrees of pulmonary fibrosis. The triggers of the fibroproliferative process in IIP remain enigmatic but recent attention has been directed towards chemokine involvement in this process.

METHODS

The expression of two chemokine receptors, CCR7 and CXCR4, and their respective ligands, CCL19, CCL21, and CXCL12, were examined in surgical lung biopsies (SLBs) from patients with IIP. Transcript and protein expression of these receptors and their ligands was compared with that detected in histologically normal margin SLBs.

RESULTS

CCR7 and CXCR4 were detected by gene array and real time polymerase chain reaction analysis and CCR7, but not CXCR4, expression was significantly raised in usual interstitial pneumonia (UIP) relative to biopsies from patients diagnosed with non-specific interstitial pneumonia (NSIP) or respiratory bronchiolitis/interstitial lung disease (RBILD). CCR7 protein was expressed in interstitial areas of all upper and lower lobe UIP SLBs analysed. CCR7 expression was present in 50% of NSIP SLBs, and CCR7 was restricted to blood vessels and mononuclear cells in 75% of RBILD SLBs. Immune cell specific CXCR4 expression was seen in IIP and normal margin biopsies. CCR7 positive areas in UIP biopsies were concomitantly positive for CD45 (the leucocyte common antigen) but CCR7 positive areas in all IIP SLBs lacked the haemopoietic stem cell antigen CD34, collagen 1, and alpha smooth muscle actin.

CONCLUSION

This molecular and immunohistochemical analysis showed that IIPs are associated with abnormal CCR7 transcript and protein expression.

Nonspecific interstitial pneumonia (NSIP)

Nonspecific interstitial pneumonia (NSIP) represents one histologic subtype of idiopathic interstitial pneumonia (IIP). NSIP is typified by temporal homogeneity and less profusion of fibroblastic foci than is seen with usual interstitial pneumonia (UIP), the most common IIP. Clinically patients with NSIP present with similar symptoms (cough and dyspnea) when compared to patients with UIP. The duration of these symptoms prior to presentation is variable. The finding of fever may be more common in NSIP and clubbing may be more common in UIP; however, both findings can be seen in either UIP or NSIP. Physiological findings typically demonstrate a restrictive ventilatory defect with decreased gas transfer; little difference exists between UIP and NSIP. High resolution computed tomography (HRCT) scans are more likely to show honeycombing with UIP and a ground-glass pattern with NSIP, however, either of these findings can be seen with UIP or NSIP. The most striking differential feature between NSIP and UIP is the markedly better prognosis for patients with NSIP, a finding that cannot be explained by baseline differences in physiology or radiographic features. In this article we explore the clinical, physiological, and radiographic features of NSIP. We also review available information regarding response to therapy and prognosis.

Prognostication in chronic obstructive pulmonary disease: implications for lung transplantation

Chronic obstructive pulmonary disease (COPD) is the most common disease for which single lung transplantation (SLT) is performed and is a frequent reason for bilateral lung transplantation (BLT). Recent data suggest a favorable survival advantage for patients with COPD undergoing lung transplantation compared with other diagnoses. This has led some investigators to question whether transplantation leads to improved survival in COPD patients compared with alternative treatment and whether this surgical therapy is appropriate in these individuals. These viewpoints may reflect the difficulties inherent in accurately predicting short- and long-term survival in patients with advanced COPD. Our review of the available data suggests that clinical, physiological, and radiographic features allow the identification of COPD patients with increased mortality despite maximal medical therapy. In these high risk individuals transplantation remains a viable therapeutic option.

Patient stratification in the management of acute bacterial exacerbation of chronic bronchitis: the role of levofloxacin 750 mg

This is the first prospective clinical trial in which patients with acute bacterial exacerbation of chronic bronchitis have been stratified by degree of underlying illness. Uncomplicated patients were randomised to levofloxacin 750 mg once daily (q.d.) for 3 days or azithromycin q.d. for 5 days. Complicated patients were randomised to levofloxacin 750 mg q.d. for 5 days or amoxicillin 875 mg/clavulanate 125 mg twice daily for 10 days. Regardless of therapy, complicated patients demonstrated lower clinical and microbiological success than uncomplicated patients. Clinical success for clinically evaluable patients was similar for levofloxacin and azithromycin (93.0 versus 90.1%, respectively), and levofloxacin and amoxicillin/clavulanate (79.2 versus 81.7%, respectively). For microbiologically evaluable patients, clinical response to levofloxacin for 3 days was superior to azithromycin for 5 days (96.3 versus 87.4%, respectively), and levofloxacin for 5 days was similar to amoxicillin/clavulanate for 10 days (81.4 versus 80.9%, respectively). Microbiological eradication was superior for levofloxacin for 3 days compared with azithromycin for 5 days (93.8 versus 82.8%, respectively), and similar for levofloxacin and amoxicillin/clavulanate for 10 days (81.4 versus 79.8%, respectively). In conclusion, levofloxacin 750 mg for 3 days was comparable to azithromycin for 5 days for uncomplicated patients with acute bacterial exacerbation of chronic bronchitis, while 5 days of 750 mg levofloxacin was comparable to 10 days of amoxicillin/clavulanate for complicated acute bacterial exacerbation of chronic bronchitis.

Comparison of disease progression and mortality of connective tissue disease-related interstitial lung disease and idiopathic interstitial pneumonia

OBJECTIVE

To compare disease progression and mortality between idiopathic interstitial pneumonia (IIP) and interstitial lung disease (ILD) due to connective tissue diseases (CTD) including scleroderma, rheumatoid arthritis, systemic lupus, polymyositis, dermatomyositis, Sjögren's syndrome, and mixed CTD.

METHODS

A case-control study of patients with CTD-ILD (n = 46) and IIP controls (n = 51), seen at the University of Michigan between July 1,1998 and June 30,1999 and followed until March 30, 2002, was conducted. Survival analysis and Cox regression were performed to estimate survival, accounting for demographic and clinical parameters, including pulmonary function tests and high resolution computed tomography (HRCT) diagnosis and scoring.

RESULTS

Median followup time was 4.4 person-years. Five-year survival in the IIP group was 51.9% (95% confidence interval [95% CI] 30.8-69.4) versus 43.4% (95% CI 21.1-63.9) in the CTD-ILD group. There were no significant differences among HRCT diagnostic categories between IIP and CTD-ILD. A fibrotic score > or = 2 was associated with decreased survival among the entire group. Age at diagnosis and most recent forced vital capacity were significant predictors of mortality when adjusted for IIP versus CTD-ILD diagnosis, sex, and interstitial score.

CONCLUSION

Contrary to expectation, CTD-ILD compared with IIP appears to be associated with a worse prognosis when adjusted for age. A higher fibrotic score is suggestive of decreased survival.

Augmented pulmonary IL-4 and IL-13 receptor subunit expression in idiopathic interstitial pneumonia

BACKGROUND

Some idiopathic interstitial pneumonias (IIPs) are characterised by fibroproliferation and deposition of extracellular matrix. Because efficacious treatment options are limited, research has been directed towards understanding the cytokine networks that may affect fibroblast activation and, hence, the progression of certain IIPs.

AIMS

To examine the expression of interleukin 4 (IL-4), IL-13, and their corresponding receptor subunits in the various forms of IIP and normal patient groups.

METHODS

Molecular and immunohistochemical analysis of IL-4, interferon gamma (IFNgamma), IL-13, IL-4 receptor (IL-R), and IL-13 receptor subunits in surgical lung biopsies (SLBs) from 39 patients (21 usual interstitial pneumonia (UIP), six non-specific interstitial pneumonia (NSIP), eight respiratory bronchiolitic interstitial lung disease (RBILD), and five normal controls).

RESULTS

Molecular analysis demonstrated that IL-13Ralpha2, IL-13Ralpha1, and IL-4Ralpha were present in a greater proportion of upper and lower lobe biopsies from patients with UIP than patients with NSIP and RBILD. Immunohistochemical analysis of patients with UIP, NSIP, and RBILD revealed interstitial staining for all three receptor subunits, whereas such staining was only seen in mononuclear cells present in normal SLBs. Fibroblastic foci in patients with UIP strongly stained for IL-4Ralpha and IL-13Ralpha2. Localised expression of IL-4Ralpha was also seen in SLBs from patients with NSIP but not in other groups.

CONCLUSION

Some histological subtypes of IIP are associated with increased pulmonary expression of receptor subunits responsive to IL-4 and IL-13. These findings may be of particular importance in understanding the pathogenesis of IIP and, more importantly, may provide important novel therapeutic targets.

Radiological versus histological diagnosis in UIP and NSIP: survival implications

BACKGROUND

High resolution computed tomography (HRCT) has an important diagnostic role in idiopathic interstitial pneumonia (IIP). We hypothesised that the HRCT appearance would have an impact on survival in patients with IIP.

METHODS

HRCT scans from patients with histological usual interstitial pneumonia (UIP; n=73) or histological non-specific interstitial pneumonia (NSIP; n=23) were characterised as definite UIP, probable UIP, indeterminate, probable NSIP, or definite NSIP. Cox regression analysis examined the relationships between histopathological and radiological diagnoses and mortality, controlling for patient age, sex, and smoking status.

RESULTS

All 27 patients with definite or probable UIP on HRCT had histological UIP; 18 of 44 patients with probable or definite NSIP on HRCT had histological NSIP. Patients with HRCT diagnosed definite or probable UIP had a shorter survival than those with indeterminate CT (hazards ratio (HR) 2.43, 95% CI 1.06 to 5.58; median survival 2.08 v 5.76 years) or HRCT diagnosed definite or probable NSIP (HR 3.47, 95% CI 1.58 to 7.63; median survival 2.08 v 5.81 years). Patients with histological UIP with no HRCT diagnosis of probable or definite UIP fared better than patients with histological UIP and an HRCT diagnosis of definite or probable UIP (HR 0.49, 95% CI 0.25 to 0.98; median survival 5.76 v 2.08 years) and worse than those with a histological diagnosis of NSIP (HR 5.42, 95% CI 1.25 to 23.5; median survival 5.76 v >9 years).

CONCLUSIONS

Patients with a typical HRCT appearance of UIP experience the highest mortality. A surgical lung biopsy is indicated for patients without an HRCT appearance of UIP to differentiate between histological UIP and NSIP.

Clinical significance of histological classification of idiopathic interstitial pneumonia

Patients with idiopathic interstitial pneumonias (IIPs) can be subdivided into groups based on the histological appearance of lung tissue obtained by surgical biopsy. The quantitative impact of histological diagnosis, baseline factors and response to therapy on survival has not been evaluated. Surgical lung biopsy specimens from 168 patients with suspected IIP were reviewed according to the latest diagnostic criteria. The impact of baseline clinical, physiological, radiographic and histological features on survival was evaluated using Cox regression analysis. The predictive value of honeycombing on high-resolution computed tomography (HRCT) as a surrogate marker for usual interstitial pneumonia (UIP) was examined. The response to therapy and survival of 39 patients treated prospectively with high-dose prednisone was evaluated. The presence of UIP was the most important factor influencing mortality. The risk ratio of mortality when UIP was present was 28.46 (95% confidence interval (CI) 5.5-148.0; p=0.0001) after controlling for patient age, duration of symptoms, radiographic appearance, pulmonary physiology, smoking history and sex. Honeycombing on HRCT indicated the presence of UIP with a sensitivity of 90% and specificity of 86%. Patients with nonspecific interstitial pneumonia were more likely to respond or remain stable (9 of 10) compared to patients with UIP (14 of 29) after treatment with prednisone. Patients remaining stable had the best prognosis. The risk ratio of mortality for stable patients compared to nonresponders was 0.32 (95% CI 0.11-0.93; p=0.04) in all patients and 0.33 (95% CI 0.12-0.96; p=0.04) in patients with UIP. The histological diagnosis of usual interstitial pneumonia is the most important factor determining survival in patients with suspected idiopathic interstitial pneumonia. The presence of honeycombing on high-resolution computed tomography is a good surrogate for usual interstitial pneumonia and could be utilized in patients unable to undergo surgical lung biopsy. Patients with nonspecific interstitial pneumonia are more likely to respond or remain stable following a course of prednisone. Patients remaining stable following prednisone therapy have the best prognosis.

Lung and heart-lung transplant practice patterns in pulmonary hypertension centers

BACKGROUND

Transplant practice patterns for pulmonary hypertension in the epoprostenol era are unknown.

METHODS

Thirty-five centers in North America, Europe, and Israel were surveyed regarding practice patterns for lung and heart-lung transplant.

RESULTS

New York Heart Association class and distance on a 6-minute walk were considered most useful for deciding who to refer for listing. Patients with New York Heart Association class I to II were referred for listing in 26% of centers, while 57% were classified as New York Heart Association class III or greater after epoprostenol failure. Twenty-nine of the 35 centers had transplant programs that performed approximately 75% of the International Registry volume annually. A double lung transplant was preferred by 83% of centers and heart-lung transplant in the remaining centers. The wait time for lung transplant averaged 16.8 months (range 4-36) and for heart-lung transplant averaged 21.3 months (range 6-36) and was significantly longer in the United States. The mean maximum age for heart-lung transplant was 51.4 years (range 35-65), double lung transplant 58.3 years (range 45-65), and single lung transplant 63.1 years (range 50-70). Fifty-three percent of centers transplant New York Heart Association class III or IV patients, 26% class IIIb-IV, and 21% only class IV. Eighty percent of centers use a transplant hold status. Major unqualified exclusions were hepatitis in 38%, 1 or more hepatic (90%) or renal (100%) criteria, smoking 97%, and obesity in 93%.

CONCLUSIONS

Physicians and patients should be aware of the considerable variability in practice patterns for transplantation in pulmonary hypertension, despite published guidelines.

Pulmonary function tests in interstitial lung disease: what role do they have?

Pulmonary function tests have been widely accepted and utilized in the management of interstitial lung diseases. Although the tests performed have changed little over the past several decades, extensive literature has been published highlighting their clinical role in the diagnosis, staging, prognostication, and follow-up of patients with a wide variety of interstitial lung diseases.

Histopathologic variability in usual and nonspecific interstitial pneumonias

Findings of surgical lung biopsy (SLB) are important in categorizing patients with idiopathic interstitial pneumonia (IIP). We investigated whether histologic variability would be evident in SLB specimens from multiple lobes in patients with IIP. SLBs from 168 patients, 109 of whom had multiple lobes biopsied, were reviewed by three pathologists. A diagnosis was assigned to each lobe. A different diagnosis was found between lobes in 26% of the patients. Patients with usual interstitial pneumonia (UIP) in all lobes were categorized as concordant for UIP (n = 51) and those with UIP in at least one lobe were categorized as discordant for UIP (n = 28). Patients with nonspecific interstitial pneumonia (NSIP) in all lobes were categorized as having fibrotic (n = 25) or cellular NSIP (n = 5). No consistent distribution of lobar histology was noted. Patients concordant for UIP were older (63 +/- 9 [mean +/- SD] yr; p < 0.05 as compared with all other groups) than those discordant for UIP (57 +/- 12 yr) or with fibrotic NSIP (56 +/- 11 yr) or cellular NSIP (50 +/- 9 yr). Semiquantitative high-resolution computed tomography demonstrated a varied profusion of fibrosis (p < 0.05 for all group comparisons), with more fibrosis in concordant UIP (2.13 +/- 0.62) than in discordant UIP (1.42 +/- 0.73), fibrotic NSIP (0.83 +/- 0.58), or cellular NSIP (0.44 +/- 0.42). Survival was better for patients with NSIP than for those in both UIP groups (p < 0.001), although survival in the two UIP groups was comparable (p = 0.16). Lobar histologic variability is frequent in patients with IIP, patients with a histologic pattern of UIP in any lobe should be classified as having UIP.

Unexplained exertional limitation: characterization of patients with a mitochondrial myopathy

Exercise intolerance is a common complaint, the cause of which often remains elusive after a comprehensive evaluation. In this report, we describe 28 patients with unexplained dyspnea or exertional limitation secondary to biopsy-proven mitochondrial myopathies. Patients were prospectively identified from a multidisciplinary dyspnea clinic at a tertiary referral center. All patients were without underlying pulmonary, cardiac, or other neuromuscular disorders. Patients underwent history, physical examination, complete pulmonary function testing, respiratory muscle testing, cardiopulmonary exercise testing, and muscle biopsy. Results were compared with a group of normal control subjects. The estimated period prevalence was 8.5% (28 of 331). Spirometry, lung volumes, and gas exchange were normal in patients and control subjects. Compared with control subjects, the patient group demonstrated decreased exercise capacity (maximum achieved V O(2) 67 versus 104% predicted; p < 0.0001) and respiratory muscle weakness (PI(max) 77 versus 115% predicted; p = 0.001). These patients have a characteristic exercise response that was hyperventilatory (peak VE/V CO(2); 55 versus 42) and hypercirculatory (maximum heart rate - baseline heart rate/V O(2)max - baseline V O(2)max; 91 versus 41) compared to control subjects. Patients stopping exercise due to dyspnea (n = 16) (as compared with muscle fatigue, n = 11) displayed weaker respiratory muscles (Pdi(max) 61 versus 115 cm H(2)O; p = 0.01) and were more likely to reach mechanical ventilatory limitation (V Emax/ MVV 0.81 versus 0.58; p = 0.02). The sensation of dyspnea was related to indices of respiratory muscle function including respiratory rate and inspiratory flow. We conclude that mitochondrial myopathies are more prevalent than previously reported. The characteristic physiological profile may be useful in the diagnostic evaluation of mitochondrial myopathy.

Apoptosis induction and cell cycle perturbation in established cell lines by peroxysomicine A1 (T-514)

Peroxysomicine A1, a novel potential anticancer compound induced cell death in established cell lines and in a primary culture of rat neonatal cardiomyocytes. Non-transformed cells are less sensitive to the compound than transformed cell lines. Fluorescent microscopy of dying cells stained with DNA-specific dyes revealed chromatin condensation and nuclear fragmentation as well as membrane blebbing characteristic of apoptosis. Flow cytometry of cells treated with peroxysomicine A1, demonstrated appearance of cells containing less than 2C DNA, that indicated degradation of nuclear DNA, another hallmark of apoptotic cell death. Z-VAD, a nonspecific caspase inhibitor, prevented DNA fragmentation but not cell death registered by permeabilization of cell outer membrane. Peroxysomicine A1 also inhibited proliferation of various cell lines. Flow cytometry analysis showed significant accumulation of dividing cells in G2/M phases of cell cycle indicating, most likely delay in G2. These results provide initial insight into the mechanisms of action of peroxysomicine A1 and suggest that peroxysomicine A1 is a potent inhibitor of cell proliferation and inducer of apoptosis and may be a useful antineoplastic chemotherapeutic agent.

Short-term and long-term outcomes after bilateral lung volume reduction surgery : prediction by quantitative CT

OBJECTIVES

To evaluate selection criteria and duration of benefit for patients undergoing lung volume reduction surgery (LVRS).

METHODS

Eighty-nine consecutive patients with severe emphysema who underwent bilateral LVRS were prospectively followed up for up to 3 years. Patients underwent preoperative pulmonary function testing, 6-min walk, chest CT, and answered a baseline dyspnea questionnaire. CT scans in 65 patients were analyzed for emphysema extent and distribution using the percentage of emphysema in the lung, percentage of normal lower lung, and the CT emphysema ratio (CTR, an index of the craniocaudal distribution of emphysema). All patients underwent at least 6 weeks of pulmonary rehabilitation prior to surgery. Outcome measures were FEV(1), 6-min walk distance, and transitional dyspnea index (TDI).

RESULTS

Compared to baseline, FEV(1) was significantly increased at 3, 6, 12, 18, 24, and 36 months after surgery (p < or = 0.008). The 6-min walk distance increased from 871 feet (baseline) to 1,110 feet (3 months), 1,214 feet (6 months), 1,326 feet (12 months), 1,342 feet (18 months), 1,371 feet (24 months), and 1,390 feet (36 months) after surgery. Despite a decline in FEV(1) over time, 6-min walk distance was preserved. Dyspnea as measured by TDI improved at 3, 6, 12, 18, 24, and 36 months after surgery. A high CTR was the best predictor of a 12% increase over baseline and an absolute increase of 200 mL in FEV(1), although with a low area under the receiver operating characteristic curve. In addition, the sensitivity and negative predictive value of the CTR were limited. No radiographic or physiologic predictor was able to consistently predict a successful increase in walk distance or TDI.

CONCLUSION

LVRS improves pulmonary function, decreases dyspnea, and enhances exercise capacity in many patients with severe emphysema, although improvement wanes 36 months after surgery.

Diaphragmatic shape change after lung volume reduction surgery

Diaphragmatic shape in normal patients was significantly different from shape in emphysema patients. Postoperative diaphragmatic shape in patients with good clinical outcome differed from preoperative shape and was similar to shape in normal patients. In patients with poor clinical outcome, surgery appeared to have little effect on diaphragm shape.

Oxygen desaturation on the six-minute walk test and mortality in untreated primary pulmonary hypertension

There are no reliable predictors of mortality in primary pulmonary hypertension (PPH). This study assessed whether exercise oxygen desaturation and distance achieved during a six-minute walk are associated with mortality in moderately symptomatic patients with PPH. Thirty-four patients with PPH underwent a pretreatment six-minute walk test, and an invasive haemodynamic assessment of pulmonary vasodilator reserve, to select the best treatment option (epoprostenol in 27 and nifedipine in 7). Median follow-up was 26 months (12 months for the nonsurvivors was 26%), and median survival, >46 months by Kaplan-Maier estimate. The mean+/-SD distance walked was 275+/-155 m and reduction in arterial oxygen saturation (Sa,O2) at maximal distance (deltaSa,O2) was 8.4+/-4.5%). A distance < or =300 m increased mortality risk by 2.4, and a deltaSa,O2 of > or = 10% increased mortality risk by 2.9. Only Sa,O2 at peak distance, deltaSa,O2 and pulmonary vascular resistance (PVR) were related to mortality. After adjusting for PVR, there remained a 27% increase in risk of death for each per cent decrease in Sa,O2. The six-minute walk distance and exercise oxygen saturation may be helpful in selecting patients with primary pulmonary hypertension for whom transplant listing is appropriate.

Acute exacerbation of chronic bronchitis: disease-specific issues that influence the cost-effectiveness of antimicrobial therapy

BACKGROUND

Acute exacerbation of chronic bronchitis (AECB) is a common condition, with substantial associated costs and morbidity. Research efforts have focused on innovations that will reduce the morbidity associated with AECB. Health care payers increasingly expect that the results of evidence-based economic evaluations will guide practitioners in their choice of cost-effective interventions.

OBJECTIVES

To provide a framework on which to base effective and efficient antimicrobial therapy for AECB, we present a concise clinical review of AECB, followed by an assessment of the available data on the economic impact of this disease. We then address several AECB-specific issues that must be considered in cost-effectiveness analyses of AECB antimicrobial interventions.

METHODS

Published literature on the clinical and economic impact of AECB was identified using MEDLINE, pre-MEDLINE, HealthSTAR, CINAHL, Current Contents/All Editions, EMBASE, and International Pharmaceutical Abstracts databases. Other potential sources were identified by searching for references in retrieved articles, review articles, consensus statements, and articles written by selected authorities.

RESULTS

In evaluating cost-effectiveness analyses of AECB antimicrobial therapy it is critical to (1) use the disease-free interval as an outcome measure, (2) evaluate the sequence of multiple therapies, (3) address the impact of both current and future antibiotic resistance, and (4) measure all appropriate AECB-associated costs, both direct and indirect.

CONCLUSIONS

Incorporating these approaches in economic analyses of AECB antimicrobial therapy can help health care organizations make evidence-based decisions regarding the cost-effective management of AECB.

Steroids in idiopathic pulmonary fibrosis: a prospective assessment of adverse reactions, response to therapy, and survival

PURPOSE

We evaluated the risk and potential benefit of high-dose corticosteroid therapy in patients with idiopathic pulmonary fibrosis.

SUBJECTS AND METHODS

We prospectively studied 41 patients with previously untreated, biopsy-proven idiopathic pulmonary fibrosis. Before treatment, we calculated clinical, radiographic, and physiologic severity-of-illness scores for each patient. We scored high-resolution computerized tomographic (CT) scans for ground glass and interstitial opacity. We determined the extent of cellular infiltration, interstitial fibrosis, desquamation, and granulation in open lung biopsy samples. Patients were monitored monthly for steroid-related side effects, response to therapy at 3 months, and mortality.

RESULTS

All patients experienced at least one steroid-induced side effect. Eleven (27%) patients were nonresponders, 11 (27%) were responders, and 19 (46%) remained stable. Of the 19 patients who died during a mean (+/- SD) follow-up of 3.3 +/- 2.3 years, 8 (42%) lost weight during the initial 3 months of steroid therapy; only 3 (14%) of the 22 patients still living (P = 0.08) experienced weight loss. In a multivariate analysis, greater fibrosis (hazard ratio [HR] = 1.4 per unit increase; 95% confidence interval [CI]: 1.0 to 1.9; P = 0.03) and cellularity (RR = 1.9 per unit increase; 95% CI: 1.3 to 2.8; 3, P <0.001) in the biopsy sample and whether a patient was classified as a responder (RR = 0.4 versus nonresponder; 95% CI: 0.2 to 1.0; P = 0.05) or stable (RR = 0.2 versus nonresponder; 95% CI: 0.1 to 0.6, P <0.001) after steroid therapy were associated with mortality.

CONCLUSION

Corticosteroid treatment for idiopathic pulmonary fibrosis is associated with substantial morbidity. Patients who remain stable or respond to corticosteroid therapy have better survival than those who fail to respond. Whether this difference reflects an effect of treatment or less severe disease can be determined only in a randomized trial.

The spectrum of acute bronchitis. Using baseline factors to guide empirical therapy

The optimal therapy for acute bronchitis depends on the causative pathogen and the presence or absence of underlying lung disease. Because there is no fast, reliable way to identify the pathogen, physicians have to rely on clinical judgment and epidemiologic characteristics. In this article, Drs Flaherty, Saint, Fendrick, and Martinez discuss how an evidence-based approach to treatment may help ensure that efficacious therapy is available in the future.

Diagnosing interstitial lung disease: a practical approach to a difficult problem

Interstitial lung disease has a variety of causes: environmental, infectious, autoimmune, and drug-related. Accurate diagnosis is essential because the prognosis and treatment of the disease varies widely depending on the cause. However, the respiratory symptoms and pulmonary radiographic picture of these various causes of interstitial lung disease are often similar, making the diagnosis of its cause confusing and frustrating. The practical, algorithmic approach to diagnosis outlined here identifies key diagnostic clues in the patient's history, physical exam, and radiographic findings.

DNA topoisomerase II inhibition by peroxisomicine A(1) and its radical metabolite induces apoptotic cell death of HL-60 and HL-60/MX2 human leukemia cells

Peroxisomicine A(1) (T-514) is a dimeric anthracenone first isolated from the plant Karwinskia humboldtiana. The compound presents a high and selective toxicity toward liver and skin cell cultures and is currently the subject of preclinical studies as an antitumor drug. To date, the molecular basis for its diverse biological effects remains poorly understood. To elucidate its mechanism of action, we studied its interaction with DNA and its effects on human DNA topoisomerases. Practically no interaction with DNA was detected. Peroxisomicine was found to inhibit topoisomerase II but not topoisomerase I. DNA relaxation and decatenation assays indicated that the drug interferes with the catalytic activity of topoisomerase II but does not stimulate DNA cleavage, in contrast to conventional topoisomerase poisons such as etoposide. Two human leukemia cell lines sensitive or resistant to mitoxantrone were used to assess the cytotoxicity of the toxin and its effect on the cell cycle. In both cases, peroxisomicine treatment was associated with a loss of cells from every phase of the cell cycle and was accompanied by a large increase in the sub-G1 region which is characteristic of apoptotic cells. The cell cycle changes were more pronounced with the sensitive HL-60 cells than with the resistant HL-60/MX2 cells (with reduced topoisomerase II activity), in agreement with the cytotoxicity measurements. Treatment of HL-60 cells with T-514 stimulated the cleavage of the poly(ADP-ribose) polymerase by intracellular proteases such as caspase-3. The cytometry and Western blot analyses reveal that peroxisomicine induces apoptosis in leukemia cells. In addition, we characterized a catabolite of peroxisomicine, named T-510R, in the form of a highly stable radical metabolite. The electron spin resonance and mass spectrometry data are consistent with the formation of an anionic semiquinonic radical. The oxidized product T-510R inhibits topoisomerase II with a reduced efficiency compared to the parent toxin and was found to be about 3-4 times less toxic to both the sensitive and resistant leukemia cell lines than T-514. Collectively, the results suggest that topoisomerase II inhibition plays a role in the cytotoxicity of the plant toxin peroxisomicine. Inhibition of topoisomerase II may serve as an inducing signal triggering the apoptotic cell death of leukemia cells exposed to the toxin. The dihydroxyanthracenone unit may represent a useful chemotype for the preparation of topoisomerase II-targeted anticancer agents.

Spectrum of Aspergillus infection in lung transplant recipients: case series and review of the literature

STUDY OBJECTIVES

(1) To define the incidence and natural history of Aspergillus colonization and infection in lung transplant recipients, and (2) to assess the impact of prophylaxis, surveillance, and therapy on the incidence and outcome of the disease.

DESIGN

Retrospective review of 133 consecutive single or bilateral lung transplantations performed at a single institution, and review of the published literature.

RESULTS

Airway colonization, isolated tracheobronchitis, and invasive pneumonia due to Aspergillus species occurred in 29%, 5%, and 8% of our series, and in 26%, 4%, and 5% of the pooled published data (all series, including ours), respectively. Greater than 50% of all diagnoses were made in the first 6 months after transplantation in both our series and the published literature. Incidence of progression from airway colonization to invasive disease was 1 in 38 in our series and 3 of 97 (3%) in the pooled published data. In patients with isolated tracheobronchitis, all 6 patients in our series and 41 of 50 patients (82%) in all published series, including ours, responded to antifungal therapy and/or surgical debridement. Among patients with invasive pneumonia or disseminated disease, however, 5 of 10 patients in our series and 26 of 64 patients (41%) in the pooled series survived their infection.

CONCLUSIONS

The role of antifungal therapy in Aspergillus airway colonization in lung transplant recipients is unclear. Data support a strategy of scheduled screening bronchoscopy followed by aggressive treatment for isolated Aspergillus tracheobronchitis in lung transplant recipients.