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This study aims to validate the large-scale application of self-sensing concrete in airport runway pavements and to use electrical resistance tomography (ERT) for characterizing spatially distributed damage during accelerated pavement testing. This self-sensing concrete not only retains the expected mechanical properties of typical airport pavements, but it can also sense deformation and strain. First, sensing properties were encoded in concrete pavements by modifying the cement-aggregate interface with multi-walled carbon nanotube (MWCNT) thin films. MWCNT thin films were spray-coated onto dried fine and coarse aggregates, and the film-coated aggregates were directly used for concrete casting. Second, an ERT algorithm was implemented for spatial conductivity mapping of self-sensing concrete pavements. Extensive laboratory tests were conducted on different sized specimens for characterizing their spatial damage detection performance. Last, a full-scale concrete airport pavement slab was cast with self-sensing concrete patches at locations where damage was expected. A heavy vehicle simulator was employed for accelerated pavement testing to induce cracks, while ERT measurements were collected at periodic intervals during testing. The results confirmed that the severities, locations, and patterns of cracks could be identified from the reconstructed ERT conductivity maps. Furthermore, subsurface damage features were identified prior to these cracks propagated and became visible on the surface.

The clinical significance and treatment strategies for minimal acute rejection (grade A1), the most common form of acute rejection (AR), remain controversial. In this retrospective single-center cohort study of 441 lung transplant recipients, we formally evaluate the association between minimal AR and chronic lung allograft dysfunction (CLAD) and test a novel hypothesis using bronchoalveolar lavage (BAL) CXCL9 concentration during minimal AR as a biomarker of subsequent CLAD development. In univariable and multivariable models adjusted for all histopathologic injury patterns, minimal AR was not associated with CLAD development. However, minimal AR with elevated BAL CXCL9 concentrations markedly increased CLAD risk in a dose-response manner. Minimal AR with CXCL9 concentrations greater than the 25th, 50th, and 75th percentile had adjusted hazard ratios (HRs) for CLAD of 1.1 (95% confidence interval [CI] 0.8-1.6), 1.6 (95% CI 1.1-2.3), and 2.2 (95% CI 1.4-3.4), respectively. Thus we demonstrate the utility of BAL CXCL9 measurement as a prognostic biomarker that allows discrimination of recipients at increased risk of CLAD development after minimal AR. BAL CXCL9 measurement during transbronchial biopsies may provide clinically useful prognostic data and guide treatment decisions for this common form of AR, as a possible strategy to minimize CLAD development.

The impact of allograft injury time of onset on the risk of chronic lung allograft dysfunction (CLAD) remains unknown. We hypothesized that episodes of late-onset (≥6 months) allograft injury would produce an augmented CXCR3/ligand immune response, leading to increased CLAD. In a retrospective single-center study, 1894 transbronchial biopsy samples from 441 lung transplant recipients were reviewed for the presence of acute rejection (AR), lymphocytic bronchiolitis (LB), diffuse alveolar damage (DAD), and organizing pneumonia (OP). The association between the time of onset of each injury pattern and CLAD was assessed by using multivariable Cox models with time-dependent covariates. Bronchoalveolar lavage (BAL) CXCR3 ligand concentrations were compared between early- and late-onset injury patterns using linear mixed-effects models. Late-onset DAD and OP were strongly associated with CLAD: adjusted hazard ratio 2.8 (95% confidence interval 1.5-5.3) and 2.0 (1.1-3.4), respectively. The early-onset form of these injury patterns did not increase CLAD risk. Late-onset LB and acute rejection (AR) predicted CLAD in univariable models but lost significance after multivariable adjustment for late DAD and OP. AR was the only early-onset injury pattern associated with CLAD development. Elevated BAL CXCR3 ligand concentrations during late-onset allograft injury parallel the increase in CLAD risk and support our hypothesis that late allograft injuries result in a more profound CXCR3/ligand immune response.

Primary graft dysfunction (PGD) is a possible risk factor for bronchiolitis obliterans syndrome (BOS) following lung transplantation; however, the mechanism for any such association is poorly understood. Based on the association of TGF-β with acute and chronic inflammatory disorders, we hypothesized that it might play a role in the continuum between PGD and BOS. Thus, the association between PGD and BOS was assessed in a single-center cohort of lung transplant recipients. Bronchoalveolar lavage fluid concentrations of TGF-β and procollagen collected within 24 h of transplantation were compared across the spectrum of PGD, and incorporated into Cox models of BOS. Immunohistochemistry localized expression of TGF-β and its receptor in early lung biopsies posttransplant. We found an association between PGD and BOS in both bilateral and single lung recipients with a hazard ratio of 3.07 (95% CI 1.76-5.38) for the most severe form of PGD. TGF-β and procollagen concentrations were elevated during PGD (p

Staphylococcus aureus is the most commonly isolated gram-positive bacterium after lung transplantation (LT) and has been associated with poor posttransplant outcomes, but its effect on bronchiolitis obliterans syndrome (BOS) and death in the context of the allograft inflammatory environment has not been studied. A three-state Cox semi-Markovian model was used to determine the influence of allograft S. aureus and the ELR+ CXC chemokines on the survival rates and cause-specific hazards for movement from lung transplant (State 1) to BOS (State 2), from transplant (State 1) to death (State 3), and from BOS (State 2) to death (State 3). Acute rejection, pseudomonas pneumonia, bronchoalveolar lavage fluid (BALF) CXCL5 and its interaction with S. aureus all increased the likelihood of transition from transplant to BOS. Transition to death from transplant was facilitated by pseudomonas infection and single lung transplant. Movement from BOS to death was affected by the interaction between aspergillus, pseudomonas and CXCL5, but not S. aureus. S. aureus isolation had state specific effects after LT and only in concert with elevated BALF CXCL5 concentrations did it augment the risk of BOS. Pseudomonas and elevated BALF concentrations of CXCL5 continued as significant risk factors for BOS and death after BOS in lung transplantation.

In recent years, carbon nanotubes have been utilized for a variety of applications, including nanoelectronics and various types of sensors. In particular, researchers have sought to take advantage of the superior electrical properties of carbon nanotubes for fabricating novel strain sensors. This article presents a single-walled carbon nanotube (SWNT)-polyelectrolyte (PE) composite thin film strain sensor fabricated with a layer-by-layer (LbL) process. Optimization of bulk SWNT-PE strain sensor properties is achieved by varying various LbL fabrication parameters, followed by characterization of strain-sensing electromechanical responses. A resistor and capacitor (RC)-circuit model is proposed and validated with electrical impedance spectroscopy to fit experimental results and to identify equivalent circuit element parameters sensitive to strain. Experimental results suggest consistent trends between SWNT and PE concentrations to strain sensor sensitivities. Simply by adjusting the weight fraction of SWNT solutions and film thickness, strain sensitivities between 0.1 and 1.8 have been achieved. While SWNT-PE strain sensitivity is lower than some metal-foil strain gauges ($2), the LbL method allows for precise tailoring of the properties (i.e., strain sensitivity, resistivity, among others) of a high-capacity (±10,000 μm m -1) homogeneous multilayer strain sensor. © SAGE Publications 2008.

Obliterative bronchiolitis (OB) (formerly termed bronchiolitis obliterans), is a rare fibrotic disorder involving terminal and respiratory bronchioles. The term constrictive bronchiolitis is synonymous with OB. Clinically, OB is characterized by progressive (often fatal) airflow obstruction, the absence of parenchymal infiltrates on chest radiographs, a mosaic pattern of perfusion on high-resolution computed tomographic scan, poor responsiveness to therapy, and high mortality rates. Most cases of OB occur in the context of a specific risk factor. Currently, most cases of OB occur in lung transplant recipients with chronic allograft rejection or hematopoietic stem cell transplant (HSCT) recipients with graft versus host disease (GVHD). Other causes of OB include connective tissue disease (CTD) (particularly rheumatoid arthritis); lower respiratory tract infections; inhalation injury; exposure or inhalation of toxic fumes, metals, dusts, particulate matter, or pollutants; occupational exposures; drug reactions; consumption of uncooked leaves of Sauropus androgynus; chronic hypersensitivity pneumonia; diffuse neuroendocrine cell hyperplasia; miscellaneous. When no cause is identified, the term cryptogenic obliterative bronchiolitis is used. This review discusses the salient clinical, radiographic, and histological features of OB and presents a management approach. [ABSTRACT FROM AUTHOR]

Background: Esophageal intestinal metaplasia, also known as Barrett's esophagus, is the replacement of the normal epithelium with one that resembles the intestine morphologically. Generally, this includes intestinal mucin-secreting goblet cells. Barrett's esophagus is an important risk factor for adenocarcinoma development. In-vitro models for Barrett's esophagus have not, to date, focused on the induction of goblet cells in Barrett's epithelium.Aims: To explore the contribution of Math1/Atoh1 to induction of Barrett's esophagus and intestinal mucin-secreting goblet cells from normal human esophageal epithelium.Methods: We explored the level and pattern of Math1/Atoh1 mRNA and protein expression in human Barrett's esophagus. Then, using retroviral-mediated gene expression, we induced Math1 mRNA and protein expression in a human esophageal keratinocyte cell line. We evaluated the effects of this ectopic Math1 expression on cell proliferation and gene expression patterns in cells cultured under two-dimensional and three-dimensional tissue-engineering conditions.Results: Math1/Atoh1 mRNA and protein are detected in human Barrett's esophagus specimens, but the mRNA levels vary substantially. In the keratinocyte expression studies, we observed that Math1/Atoh1 ectopic expression significantly reduced cell proliferation and altered cell morphology. Moreover, Math1/Atoh1 expression is associated with a more intestinalized gene expression pattern that is distinct from that reported in after studies using other intestinal transcription factors. Most significantly, we observe the induction of the Barrett's esophagus markers Mucin-2 and Keratin-20 with Math1/Atoh1 expression.Conclusions: We conclude that ectopic Math1/Atoh1 expression makes unique contributions to intestinalization of the esophageal epithelium in Barrett's esophagus. [ABSTRACT FROM AUTHOR]

Treatment strategies for anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are evolving. Cyclophosphamide (CYC) plus corticosteroids (CSs) is the mainstay of therapy for generalized, multisystemic AAV. Historically, the combination of CYC plus CS was used for a minimum of 12 months, but concern about late toxicities associated with CYC has led to novel treatment approaches. Currently, short-course (3 to 6 months) induction treatment with CYC plus CS, followed by maintenance therapy with less toxic agents (eg, methotrexate, azathioprine, mycophenolate mofetil) is recommended. Further, methotrexate combined with CS may be adequate for limited, non-life-threatening AAV. Recent studies suggest that rituximab may be useful for induction therapy or for CYC-refractory AAV. This article reviews the key agents used to treat AAV, with a focus on pharmacology, toxicities, and monitoring. [ABSTRACT FROM AUTHOR]

Background: Hypoalbuminemia is a reliable predictor of mortality in patients with various illnesses as well as a predictor of disability and mortality in healthy older adults. The association between hypoalbuminemia and mortality in patients with idiopathic interstitial pneumonia remains unknown. The objective of this study was to examine the relationship between serum albumin concentration and mortality in a large cohort of patients with idiopathic interstitial pneumonia listed for lung transplantation.Methods: In patients classified as having idiopathic pulmonary fibrosis who were listed for lung transplantation with the United Network for Organ Sharing between January 1, 2004, and December 31, 2006 (n = 1,269), we studied the relationship between serum albumin concentration at the time of listing and mortality while awaiting transplantation.Results: Lower serum albumin was associated with increased mortality rate. Patients with lower categories of serum albumin had increased mortality rates before and after multivariable adjustment (p value for linear trend < 0.0001). Analysis with serum albumin as a continuous predictor indicated that the mortality rate increased by 54% with each 0.5 g/dL decrease in serum albumin concentration (95% confidence interval, 32 to 79%).Conclusions: Lower serum albumin is strongly and independently associated with higher mortality in patients with idiopathic interstitial pneumonia on transplant waiting lists. [ABSTRACT FROM AUTHOR]

Current guidelines recommend that the clinician, radiologist, and pathologist work together to establish a diagnosis of idiopathic interstitial pneumonia. Three clinicians, two radiologists, and two pathologists reviewed 58 consecutive cases of suspected idiopathic interstitial pneumonia. Each participant was provided information in a sequential manner and was asked to record their diagnostic impression and level of confidence at each step. Interobserver agreement improved from the beginning to the end of the review. After the presentation of histopathologic information, radiologists changed their diagnostic impression more often than did clinicians. In general, as more information was provided the confidence level for a given diagnosis improved, and the diagnoses rendered with a high level of confidence were more likely congruent with the final pathologic consensus diagnosis. The final consensus pathologist diagnosis was idiopathic pulmonary fibrosis in 30 cases. Clinicians identified 75% and radiologists identified 48% of these cases before presentation of the histopathologic information. Histopathologic information has the greatest impact on the final diagnosis, especially when the initial clinical/radiographic diagnosis is not idiopathic pulmonary fibrosis. We conclude that dynamic interactions between clinicians, radiologists, and pathologists improve interobserver agreement and diagnostic confidence. [ABSTRACT FROM AUTHOR]

This cross-sectional study examined the association between smoking and other health-related risk behaviors, individually as well as in clusters, across branches of military service in the higher risk ages of 18 to 25 years old within the 1998 Department of Defense Survey of Health-Related Behaviors among Military Personnel. Examination of the demographic variables revealed that, in general, smokers tended to be single, white, enlisted men in the 18- to 20-year age group with less education and serving in the Army or Marine Corps. Our findings support that there is an increased likelihood of co-occurrence of substance use along with other negative health-related risk behaviors found in military members. It may be practical and necessary to develop a focused survey given to those attending smoking cessation interventions, or perhaps to smokers in general, which attempts to identify associated risk behaviors and channel clients accordingly. [ABSTRACT FROM AUTHOR]

Pain is the major complaint of patients who choose acupuncture treatment. Transcutaneous electrical acupoint stimulation (TEAS) provides a safe, standardized technique without needle insertion. TEAS can be tested with the cold-pressor test, a simple, reliable, and widely used model in humansfor the induction of tonic pain. In this controlled study, the effects of TEAS on cold-pressor-induced pain were evaluated in 20 healthy human subjects. Electrical stimulation electrodes were applied to He-Gu (LI 4) and Nui-Guan (P 6) acupoints. The effects of saline plus no TEAS, 15-minute TEAS alone, 0.05 mg/kg morphine alone, and 15-minute TEAS plus morphine were assessed. Pain score ratings were evaluated at four time points from 30 to 170 seconds during the cold-pressor test. The authors observed analgesic effects in both TEAS-alone and morphine-alone sessions, and pain score rating reductions were statistically significant compared to unstimulated control (both p < 0.01). The degree of TEAS analgesia combined with 0.05 mg/kg morphine was significantly higher than TEAS alone (p < 0.01). The results support the efficacy of TEAS analgesia and suggest that combination of TEAS with low-dose morphine can achieve better pain control in a variety of clinical settings. [ABSTRACT FROM AUTHOR]

Presents information on a seminar involving the Central statistical Service (CSS) which is a government body and the reconstruction development programme (RDP). How does the CSS perform its function; What benefits the RDP can offer the CSS; Requirements of the RDP.

Background and Aims: Root axes with greater penetration ability are often considered to be beneficial in hard soils. We hypothesized that maize root phenotypes with greater plasticity (meaning reduced elongation in response to mechanical impedance, i.e. a 'stop signal') have fitness advantages over phenotypes with reduced plasticity (i.e. unimpeded root elongation) in native (virgin, uncultivated) soils, by reallocating root foraging to softer, presumably wetter, soil domains, and that the value of the stop signal reduced with soil cultivation and crop domestication., Methods: We used OpenSimRoot to simulate native and cultivated soils and evaluated maize root phenotypes with varying axial and lateral root penetration ability in water, nitrogen, and impedance regimes associated with Neolithic agriculture., Key Results: The stop signal was advantageous in native soils but was less beneficial in cultivated, irrigated soils. Reduced root foraging in hard, dry topsoil enabled root growth in deeper domains where water is available, resulting in an improved balance of resource expenditure and acquisition. The value of the stop signal declined during crop domestication with the advent of irrigation, which increased water availability in the topsoil. Soil cultivation reduced N availability, while irrigation increased N leaching, resulting in a shift in the fitness landscape, with greater lateral root length (i.e. reduced plasticity) being advantageous by colocalizing root foraging with N availability. The importance of the stop signal is evident in modern high-input systems in which drought is a limiting factor., Conclusions: Our results support the hypotheses that the reduction of lateral root growth by mechanical impedance is adaptive in native soil, but became less adaptive with soil cultivation and irrigation associated with Neolithic agriculture., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Annals of Botany Company.)

We describe how increased root cortical parenchyma wall width (CPW) can improve tolerance to drought stress in maize by reducing the metabolic costs of soil exploration. Significant variation (1.0-5.0 µm) for CPW was observed in maize germplasm. The functional-structural model RootSlice predicts that increasing CPW from 2 µm to 4 µm is associated with a ~15% reduction in root cortical cytoplasmic volume, respiration rate, and nitrogen content. Analysis of genotypes with contrasting CPW grown with and without water stress in the field confirms that increased CPW is correlated with an ~32-42% decrease in root respiration. Under water stress in the field, increased CPW is correlated with 125% increased stomatal conductance, 325% increased leaf CO2 assimilation rate, 73-78% increased shoot biomass, and 92-108% increased yield. CPW was correlated with leaf mesophyll midrib parenchyma wall width, indicating pleiotropy. Genome-wide association study analysis identified candidate genes underlying CPW. OpenSimRoot modeling predicts that a reduction in root respiration due to increased CPW would also benefit maize growth under suboptimal nitrogen, which requires empirical testing. We propose CPW as a new phene that has utility under edaphic stress meriting further investigation., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

Engineered smart microbes that deliver therapeutic payloads are emerging as treatment modalities, particularly for diseases with links to the gastrointestinal tract. Enterohemorrhagic Escherichia coli (EHEC) is a causative agent of potentially lethal hemolytic uremic syndrome. Given concerns that antibiotic treatment increases EHEC production of Shiga toxin (Stx), which is responsible for systemic disease, novel remedies are needed. EHEC encodes a type III secretion system (T3SS) that injects Tir into enterocytes. Tir inserts into the host cell membrane, exposing an extracellular domain that subsequently binds intimin, one of its outer membrane proteins, triggering the formation of attaching and effacing (A/E) lesions that promote EHEC mucosal colonization. Citrobacter rodentium (Cr), a natural A/E mouse pathogen, similarly requires Tir and intimin for its pathogenesis. Mice infected with Cr(ΦStx2dact), a variant lysogenized with an EHEC-derived phage that produces Stx2dact, develop intestinal A/E lesions and toxin-dependent disease. Stx2a is more closely associated with human disease. By developing an efficient approach to seamlessly modify the C. rodentium genome, we generated Cr&#95;Tir-M EHEC (ΦStx2a), a variant that expresses Stx2a and the EHEC extracellular Tir domain. We found that mouse precolonization with HS-PROT 3 EcT-TD4, a human commensal E. coli strain ( E. coli HS) engineered to efficiently secrete an anti-EHEC Tir nanobody, delayed bacterial colonization and improved survival after challenge with Cr&#95;Tir-M EHEC (ΦStx2a). This study suggests that commensal E. coli engineered to deliver payloads that block essential virulence determinants can be developed as a new means to prevent and potentially treat infections including those due to antibiotic resistant microbes., (© The Author(s) 2024. Published by Oxford University Press on behalf of National Academy of Sciences.)