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Perfluorooctanoic acid (PFOA) is one of the highly toxic compounds which was phased out of application in consumer products in 2015 due to its harmful effects on human and environmental health. However, this chemical was in use for many years and is still found in water resources. This study focuses on the physiological response of duckweed ( Lemna mino r) exposed to PFOA so as to determine phytotoxicity and the potential of this aquatic species to remove PFOA from the environment. A time-dependent phytotoxicity assay showed that exposure to 0.1 µg/L PFOA for 14 days resulted in the loss of chlorophyll pigment and 15-25% more chlorosis than in controls. Although exposure to PFOA for seven days resulted in chlorosis, no significant impact on physiological parameters such as photosynthetic pigment or anthocyanin content were detected. The analysis of cellular size on day zero and seven of the experiment showed that the control group showed significantly larger cell size after seven days (213 ± 6.5 µm²) compared with the day zero group (186 ± 18 µm²), while the size of the PFOA exposed group (198 ± 13 µm²) did not change significantly after seven days compared with the day zero group. The nuclear size increased significantly by 13% upon exposure to PFOA compared with the controls (ρ < 0.0001). The concentration of essential elements K, Cu, Fe, Mn, Zn, Mo were reduced in L. minor exposed to PFOA compared with the controls by 39.6, 33.4, 42.1, 35.2, 31.9, 40.2%, respectively. Additionally, PFOA accumulated in L. minor fronds and roots with an average bioaccumulation factor of 56 ± 7. Overall, while some symptoms of toxicity were observed, this study shows that L. minor can tolerate up to 0.1 µg/L PFOA, a commonly found concentrations in water bodies, and can remove PFOA from water. This study provides invaluable information regarding the phototoxicity impacts of PFOA on aquatic species and the potential for aquatic phytoremediation of PFOA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer MM declared a past co-authorship with the author JCW to the handling editor., (Copyright © 2025 Noori, Corbelli, Lincoln, Thomas, Jones, Nason, White, Lewis and Haynes.) more...

This near-infrared spectral dataset consists of 2,106 diverse mineral soil samples scanned, on average, on six different units of the same low-cost commercially available handheld spectrophotometer. Most soil samples were selected from the USDA NRCS National Soil Survey Center-Kellogg Soil Survey Laboratory (NSSC-KSSL) soil archives to represent the diversity of mineral soils (0-30 cm) found in the United States, while 90 samples were selected from Ghana, Kenya, and Nigeria to represent available African soils in the same archive. All scanning was performed on dried and sieved (<2 mm) soil samples. Machine learning predictive models were developed for soil organic carbon (SOC), pH, bulk density (BD), carbonate (CaCO3), exchangeable potassium (Ex. K), sand, silt, and clay content from their spectra in the R programming language using most of this dataset (1,976 US soils) and are included in this data release. Two model types, Cubist and partial least squares regression (PLSR) were developed using two strategies: (1) using an average of the spectral scans across devices for each sample and, (2) using the replicate spectral scans across devices for each sample. We present the internal performance of these models here. The dry spectra and Cubist models for these soil properties are available for download from 10.5281/zenodo.7586621. An example of detailed code used to produce these models is hosted at the Open Soil Spectral Library, a free service of the Soil Spectroscopy for the Global Good Network (soilspectroscopy.org), enabling broad use of these data for multiple soil monitoring applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Mention of a manufacturer or model of instrument does not imply USDA endorsement, nor should one be inferred., (© 2024 The Author(s).) more...

Many proteins lack stable 3D structures. These intrinsically disordered proteins (IDPs) or hybrid proteins containing ordered domains with intrinsically disordered protein regions (IDPRs) often carry out regulatory functions related to molecular recognition and signal transduction. IDPs/IDPRs constitute a substantial portion of the human proteome and are termed "the unfoldome". Herein, we probe the human breast cancer unfoldome and investigate relations between IDPs and key disease genes and pathways. We utilized bottom-up proteomics, MudPIT (Multidimensional Protein Identification Technology), to profile differentially expressed IDPs in human normal (MCF-10A) and breast cancer (BT-549) cell lines. Overall, we identified 2271 protein groups in the unfoldome of normal and cancer proteomes, with 148 IDPs found to be significantly differentially expressed in cancer cells. Further analysis produced annotations of 140 IDPs, which were then classified to GO (Gene Ontology) categories and pathways. In total, 65% (91 of 140) IDPs were related to various diseases, and 20% (28 of 140) mapped to cancer terms. A substantial portion of the differentially expressed IDPs contained disordered regions, confirmed by in silico characterization. Overall, our analyses suggest high levels of interactivity in the human cancer unfoldome and a prevalence of moderately and highly disordered proteins in the network. more...

Background: Communities across the U.S. have acted to eliminate or curb police presence in schools. These efforts have primarily focused on School Resource Officers. However, school staff also call upon local police to respond in their buildings, for example by calling 911. The reasons that police are called upon to respond in schools has rarely been studied., Objective: The current study aimed to identify the primary reasons that local police were asked to respond to incidents in one urban school district, and the outcomes of those responses., Participants and Setting: We analyzed 882 police incident report narratives, selected from a stratified sample of 57 schools in one urban school district during the 2017-18 school year. Incident reports, which were written by officers responding in schools, included narrative descriptions of officer intervention, the events precipitating police involvement, and outcomes of incidents., Methods: By coding incident report narratives, we identified categories describing the reasons for police response to events in schools and the outcomes of those events., Results: Most incident reports originating from school addresses (n = 730; 82.8 %) involved students. Among those reports, police most frequently responded to instances of sexual physical violence (17.5 %), physical assault (15.8 %), dysregulated behavior (11.2 %), threatening language (10.8 %), and threat of or actual school violence (4.4 %). Incidents involving students most often resulted in: (1) parents/guardians being contacted (57.3 %), (2) schools engaging in disciplinary actions (39.7 %) or school safety actions (27.0 %), and (3) child maltreatment reports being made to Crimes Against Children (a subdivision of the police department focused on child maltreatment; 26.0 %) or to the Department of Children and Families (26.2 %)., Conclusions: Findings indicate that many events leading to police responses in schools are related to maltreatment and behavioral health. These events rarely result in a criminal justice response, and most often result in action by families and schools (e.g., contacting parents/guardians, school disciplinary/safety actions), and filed reports of maltreatment. Additional supports in these areas may have the potential to reduce the perceived need to call upon police and to provide more direct access to services for students., (Copyright © 2023 Elsevier Ltd. All rights reserved.) more...

Particulate matter (PM) is a major primary pollutant emitted during wildland fires that has the potential to pose significant health risks to individuals/communities who live and work in areas impacted by smoke events. Limiting exposure is the principle measure available to mitigate health impacts of smoke and therefore the accurate determination of ambient PM concentrations during wildland fire events is critical to protecting public health. However, monitoring air pollutants in smoke impacted environments has proven challenging in that measurement interferences or sampling conditions can result in both positive and negative artifacts. The EPA has performed research on methods for the measurement of PM 2.5 in a series of laboratory-based studies including evaluation in smoke. This manuscript will summarize the results of the laboratory-based evaluation of federal equivalent method (FEM) monitors for PM 2.5 with particular attention being given to the Teledyne-API Model T640 PM Mass monitor, as compared to the filter-based federal reference method (FRM). The T640 is an optical-based PM monitor and has been gaining wide use by state and local agencies in monitoring for PM 2.5 U.S. National Ambient Air Quality Standards (NAAQS) attainment. At present, the T640 (includes both T640 and T640×) comprises ~44% of the PM 2.5 FEM monitors in U.S. regulatory monitoring networks. In addition, the T640 has increasingly been employed for the higher time resolution comparison/evaluation of low-cost PM sensors including during smoke impacted events. Results from controlled non-smoke laboratory studies using generated ammonium sulfate aerosols demonstrated a generally negative T640 measurement artifact that was significantly related to the PM 2.5 concentration and particle size distribution. Results from biomass burning chamber studies demonstrated positive and negative artifacts significantly associated with PM 2.5 concentration and optical wavelength-dependent absorption properties of the smoke aerosol. Implications : The results detailed in this paper will provide state and local air monitoring agencies with the tools and knowledge to address PM 2.5 measurement challenges in areas frequently impacted by wildland fire smoke. The observed large positive and negative artifacts in the T640 PM mass determination have the potential to result in false exceedances of the PM 2.5 NAAQS or in the disqualification of monitoring data through an exceptional event designation. In addition, the observed artifacts in smoke impacted air will have a detrimental effect on providing reliable public information when wildfires occur and also in identifying reference measurements for small sensor evaluation studies. Other PM 2.5 FEMs such as the BAM-1022 perform better in smoke and are comparable to the filter-based FRM. Care must be taken in choosing high time resolution FEM monitors that will be operated at smoke impacted sites. Accurate methods, such as the FRM and BAM-1022 will reduce the burden of developing and reviewing exceptional event request packages, data loss/disqualification, and provide states with tools to adequately evaluate public exposure risks and provide accurate public health messaging during wildfire/smoke events. more...

School connectedness is consistently associated with adolescent mental health and well-being. We investigated whether student perceptions of school connectedness were associated with anxiety and depressive symptoms, even during remote learning due to COVID-19. In June of 2020, after 13 weeks of remote learning, 320 middle and high school students in one Massachusetts school district completed an online survey that included questions about their perceptions of school connectedness, social connectedness, and symptoms of anxiety and depression. Students were approximately evenly distributed across grades, with 37% in middle school (grades 6-8) and 63% in high school (grades 9-12). School connectedness had a significant negative association with symptoms of anxiety and depression. This association persisted in models controlling for demographic factors and social connectedness. Findings indicate that school connectedness is associated with student mental health, even in the context of remote learning due to COVID-19. Schools engaged in remote learning should consider how to foster school connectedness as a means of supporting youth mental health, particularly given expected increases in the mental health needs of adolescents., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.) more...

Radiological release incidents can potentially contaminate widespread areas with radioactive materials and decontamination efforts are typically focused on populated areas, which means radionuclides may be left in forested areas for long periods of time. Large wildfires in contaminated forested areas have the potential to reintroduce these radionuclides into the atmosphere and cause exposure to first responders and downwind communities. One important radionuclide contaminant released from radiological incidents is radiocesium ( 137 Cs) due to high yields and its long half-life of 30.2 years. An Eulerian 3D photochemical transport model was used to estimate potential ambient impacts of 137 Cs re-emission due to wildfire following hypothetical radiological release scenarios. The Community Multiscale Air Quality (CMAQ) model did well at predicting levels and periods of increased PM2.5 carbon due to wildfire smoke at routine surface monitors in California during the summer of 2016. The model also did well at capturing the extent of the surface mixing layer compared to aerosol lidar measurements. Emissions from a large hypothetical wildfire were introduced into the wildland-urban interface (WUI) impacted by a hypothetical radiological release event. While ambient concentrations tended to be highest near the fire, the highest population committed effective dose equivalent by inhalation to an adult from 137 Cs over an hour was downwind where wind flows moved smoke to high population areas. Seasonal variations in meteorology (wind flows) can result in differential population impacts even in the same metropolitan area. Modeled post-incident ambient levels of 137 Cs both near these wildfires and further downwind in nearby urban areas were well below levels that would necessitate population evacuation or warrant other protective action recommendations such as shelter-in-place. These results suggest that 1) the modeling system captures local to regional scale transport and levels of PM2.5 from wildfire and 2) first responders and downwind population would not be expected to be at elevated risk from the initial inhalathion exposure of 137 Cs re-emission., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.) more...

If a radiological incident such as a nuclear power plant accident, a radiological dispersal device, or detonation of an improvised nuclear device occurs, significant areas may be contaminated. Initial cleanup priorities would likely focus on populated areas, leaving the forested areas to pass several seasons where the overhead canopy materials would fall to the forest floor. In the event of a wildfire in a radionuclide-contaminated forest, some radionuclides would be emitted in the air while the rest would remain in the ash. This paper reports on a laboratory simulation study that examines the partitioning of cesium-133 (a nonradioactive isotope of cesium) between airborne particulate matter and residual nonentrained ash when pine needles and peat are doped with cesium. Only 1-2.5% of the doped cesium in pine needles was emitted as particulate matter, and most of the cesium was concentrated in the particulate fraction greater than 10 µm in aerodynamic diameter. For peat fires, virtually all of the cesium remained in the ash. The results from this study will be used for modeling efforts to assess potential exposure risks to firefighters and the surrounding public. Implications: There is a potential for emissions of radionuclides such as cesium-137 from a wildfire over a radionuclide-contaminated forest. This paper reports on a laboratory simulation study of a wildfire with two types of biomass doped with nonradioactive cesium. This simulation suggests that only 1-2.5% of the cesium in the biomass will be emitted from the wildfire, while the rest will reside in the residual ash. In this study, pine needles were the only contributor to the air emissions of cesium; duff was not a source of cesium emissions. In this study, cesium emitted from the simulated wildfire was concentrated in the particle sizes larger than 10 µm. more...

Goals: We studied the prevalence and predictors of small-intestinal bacterial overgrowth (SIBO) in Crohn's disease (CD) outpatients and the relationship between SIBO and intestinal and/or systemic inflammation., Background: The relationship of SIBO with systemic and intestinal inflammation in CD patients is unclear., Study: In this cross-sectional study, conducted between June, 2013 and January, 2015, 92 CD patients and 97 controls with nonchronic gastrointestinal complaints were assessed for the presence of SIBO using the H2/CH4 glucose breath test. Multivariate logistic regression was performed to investigate the potential association between SIBO and demographic, disease-related data, systemic markers of inflammation (C-reactive protein, and erythrocyte sedimentation rate), and biomarker of intestinal inflammation [fecal calprotectin concentration (FCC)]., Results: The SIBO rate was significantly higher in CD patients than in controls (32.6% vs. 12.4%, respectively, P=0.0008). Patients with and without SIBO were comparable with regard to demographics, systemic inflammatory biomarkers, and disease characteristics, except for the stricturing phenotype being more common in SIBO-positive CD patients (43.3% vs. 19.3%, P=0.015). Notably, FCC was significantly higher in SIBO-positive patients (median of 485.8 vs.132.7 μg/g; P=0.004). Patients presenting increased FCC and stricturing disease had an odds of 9.43 (95% confidence interval, 3.04-11.31; P<0.0001) and 3.83 (95% confidence interval, 1.54-6.75; P=0.025) respectively, for SIBO diagnosis., Conclusions: In CD patients, SIBO is a highly prevalent condition. Stricturing phenotype and increased FCC were strongly and independently associated with the presence of SIBO. SIBO diagnostic work-up followed by directed treatment is recommended in CD patients who present stricturing disease, especially in those with concurrent intestinal inflammation. more...

Background: Maternal and newborn mortality remains high in Liberia. There is a severe rural-urban gap in accessibility to health care services. A competent midwifery workforce is able to meet the needs of mothers and newborns. Evidence shows that competence can be assured through initial education along with continuous professional development (CPD). In the past, CPD was not regulated and coordinated in Liberia which is cpommon in the African region., Aim: To Support a competent regulated midwifery workforce through continuous professional development., Methodology: A new CPD model was developed by the Liberian Board for Nursing and Midwifery. With its establishment, all midwives and nurses are required to undertake CPD programmes consisting of certified training and mentoring in order to renew their practicing license. The new model is being piloted in one county in which regular mentoring visits that include skills training are being conducted combined with the use of mobile learning applications addressing maternity health issues. Quality control of the CPD pilot is assured by the Liberian Board for Nursing and Midwifery. The mentoring visits are conducted on a clinical level but are coordinated on the national and county level., Successes and Sustainability: CPD using mobile learning on smartphones and regular mentoring visits not only improved knowledge and skills of midwives and nurses but also provided a solution to enhance accessibility in rural areas through improved communication and transportation, as well as improved career development of health personnel working in remote areas. Mentors were trained on a national, county, and health facility level in the pilot county with mentoring visits conducted regularly., Conclusion: The CPD programme of the Liberian Board for Nursing and Midwifery, currently in pilot-testing by various partners, aims to highlight the positive impact of the coordinating role of both the regulatory body and health authorities. Using regular process and programme reviews to improve capacity, knowledge, and skills of health professionals., (Copyright © 2018 Elsevier Ltd. All rights reserved.) more...

Virtual water trade is often considered a solution for restricted water availability in many regions of the world. Brazil is the world leader in the production and export of various agricultural and livestock products. The country is either a strong net importer or a strong net exporter of these products. The objective of this study is to determine the volume of virtual water contained in agricultural and livestock products imported/exported by Brazil from 1997 to 2012, and to define the water self-sufficiency index of agricultural and livestock products in Brazil. The indexes of water scarcity (WSI), water dependency (WDI) and water self-sufficiency (WSSI) were calculated for each Brazilian state. These indexes and the virtual water balance were calculated following the methodology developed by Chapagain and Hoekstra (2008) and Hoekstra and Hung (2005). The total water exports and imports embedded in agricultural and livestock products were 5.28 × 10 10 and 1.22 × 10 10  Gm 3  yr -1 , respectively, which results in positive virtual water balance of 4.05 × 10 10  Gm 3  yr -1 . Brazil is either a strong net importer or a strong net exporter of agricultural and livestock products among the Mercosur countries. Brazil has a positive virtual water balance of 1.85 × 10 10  Gm 3  yr -1 . The indexes used in this study reveal that Brazil is self-sufficient in food production, except for a few products such as wheat and rice. Horticultural products (tomato, onion, potato, cassava and garlic) make up a unique product group with negative virtual water balance in Brazil., (Copyright © 2016 Elsevier Ltd. All rights reserved.) more...

Although environmental estrogens (EE) have been found to disrupt a wide variety of developmental and reproductive processes in vertebrates, there is a paucity of information concerning their effects on organismal growth, particularly postembryonic growth. In this study, we exposed juvenile rainbow trout (Oncorhynchus mykiss) to 17β-estradiol (E2) β-sitosterol (βS), or 4-n-nonylphenol (NP) to assess the effects of EE on overall organismal growth and on the growth hormone-insulin-like-growth factor (GH-IGF) system. EE treatment significantly reduced food conversion, body condition, and body growth. EE-inhibited growth resulted from alterations in peripheral elements of the GH-IGF system, which includes multiple GH receptors (GHRs), IGFs, and IGF receptors (IGFRs). In general, E2, βS, and NP reduced the expression of GHRs, IGFs, and IGFRs; however, the effects varied in an EE-, tissue-, element type-specific manner. For example, in liver, E2 was more efficacious than either βS, and NP in reducing GHR expression, and the effect of E2 was greater on GHR 1 than GHR2 mRNA. By contrast, in gill, all EEs affected GHR expression in a similar manner and there was no difference in the effect on GHR1 and GHR 2 mRNA. With regard to IGF expression, all EEs reduced hepatic IGF1 and IGF2 mRNA levels, whereas as in gill, only E2 and NP significantly reduced IGF1 and IGF2 expression. Lastly, E2 and NP reduced the expression of IGFR1A and IGFR1B mRNA expression similarly in gill and red and white muscle, whereas βS had no effect on expression of IGFR mRNAs. These findings indicate that EEs disrupt post-embryonic growth by reducing GH sensitivity, IGF production, and IGF sensitivity., (Copyright © 2013 Elsevier Inc. All rights reserved.) more...

Acute biliary complications may result from several medical conditions such as gallstone pancreatitis, acute cholangitis, acute cholecystitis, bile leak, liver abscess and hepatic trauma. Gallstones are the most common cause of acute pancreatitis. About 25% of theses patients will develop clinically severe acute pancreatitis, usually due to necrotizing pancreatitis. Choledocholithiasis, malignant and benign biliary strictures, and stent dysfunction may cause partial or complete obstruction and infection in the biliary tract with acute cholangitis. Bile leaks are most commonly associated with hepatobiliary surgeries or invasive procedures such as open or laparoscopic cholecystectomy, hepatic resection, hepatic transplantation, liver biopsy, and percutaneous transhepatic cholangiography. Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) may have an essential role in the management of these complications., (Copyright © 2013 Elsevier Ltd. All rights reserved.) more...

Background: ERCP in Roux-en-Y gastric bypass (RYGB) patients is challenging. Balloon-assisted enteroscopy (BAE) allows access to the excluded stomach with creation of a percutaneous endoscopic gastrostomy (PEG). Transgastric self-expandable metal stent (SEMS) placement may allow antegrade ERCP in 1 session., Objective: To determine the feasibility of transgastric endoscopy and ERCP through a newly created PEG augmented by SEMS placement., Design: Prospective live animal study; human case report., Settings: Animal laboratory and endoscopy units, tertiary care medical center., Subjects: Nine domestic pigs; 1 patient., Interventions: PEG tract with SEMS placement; transgastric endoscopy through SEMS., Main Outcome Measurements: Technical success, feasibility of transgastric endoscopy., Results: Successful SEMS deployment was achieved in 9 of 9 animals. The stent was removed in 6 animals; 3 were killed within 24 hours (group A) and 3 were killed 1 week later (group B). In 3 animals, stents remained in place, they were killed 9 to 15 days later (group C). Duodenoscopy was difficult in 1 animal from group A resulting in stent dislodgment. Peristomal infection occurred in 1 animal in group B. In group C, 1 stent was buried subcutaneously and 1 completely migrated out. Necropsy showed no peritoneal fluid or peritonitis in any animal. In the 1 patient, BAE-assisted PEG and SEMS placement in the excluded stomach allowed antegrade ERCP and biliary sphincterotomy without adverse events., Limitations: Small number of subjects., Conclusions: Performance of PEG with immediate SEMS placement allows for antegrade transgastric ERCP during 1 procedure. With the use of BAE, retrograde PEG/SEMS in excluded stomach allows therapeutic ERCP without need for surgery., (Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.) more...

Using two MYCN transgenic mouse strains, we established 10 transplantable neuroblastoma cell lines via serial orthotopic passage in the adrenal gland. Tissue arrays demonstrate that by histochemistry, vascularity, immunohistochemical staining for neuroblastoma markers, catecholamine analysis, and concurrent cDNA microarray analysis, there is a close correspondence between the transplantable lines and the spontaneous tumors. Several genes closely associated with the pathobiology and immune evasion of neuroblastoma, novel targets that warrant evaluation, and decreased expression of tumor suppressor genes are demonstrated. These studies describe a unique and generalizable approach to expand the utility of transgenic models of spontaneous tumor, providing new tools for preclinical investigation. more...

Bacteria in biofilms have higher antibiotic tolerance than their planktonic counterparts. A major outstanding question is the degree to which the biofilm-specific cellular state and its constituent genetic determinants contribute to this hyper-tolerant phenotype. Here, we used genome-wide functional profiling of a complex, heterogeneous mutant population of Pseudomonas aeruginosa MPAO1 in biofilm and planktonic growth conditions with and without tobramycin to systematically quantify the contribution of each locus to antibiotic tolerance under these two states. We identified large sets of mutations that contribute to antibiotic tolerance predominantly in the biofilm or planktonic setting only, offering global insights into the differences and similarities between biofilm and planktonic antibiotic tolerance. Our mixed population-based experimental design recapitulated the complexity of natural biofilms and, unlike previous studies, revealed clinically observed behaviors including the emergence of quorum sensing-deficient mutants. Our study revealed a substantial contribution of the cellular state to the antibiotic tolerance of biofilms, providing a rational foundation for the development of novel therapeutics against P. aeruginosa biofilm-associated infections. more...

In this study, cDNA for a somatostatin receptor variant (somatostatin receptor subtype 2, SSTR 2) was isolated, cloned, and sequenced from rainbow trout. A 1821-nt cDNA was isolated and found to contain a single initiation site 387-nt from the most 5' end, an open reading frame of 1116-nt, and a single putative polyadenylation site 189-nt from the most 3' end. The encoded protein contains 372 amino acids and contains seven membrane-spanning domains. Based on structural analysis, the protein was identified as a subtype 2 SSTR. These data support the emergence of a multigenic SSTR family early in the course of vertebrate evolution, concomitant with or perhaps prior to the divergence of boney fish. The distribution of SSTR 2 mRNA in tissues was determined by quantitative real time-PCR (QRT-PCR). SSTR 2 was most abundant in the brain (where it was detected in the telencephalon, optic tectum, and hypothalamus), skeletal muscle, and liver, but it also was present in the endocrine pancreas (Brockmann body) and various regions of the gastrointestinal tract (esophagus, stomach, intestine). SSTR 2 mRNA was most abundant in the brain, muscle, and liver. In vitro the Brockmann body and liver with increasing concentrations of glucose (1, 4, 10mM) resulted in increased expression of SSTR 2 mRNA. These findings contribute to the understanding of the evolution of the SSTR family and provide insight into the roles of SSTR 2 in fish., (Copyright © 2011 Elsevier Inc. All rights reserved.) more...

Bariatric surgery is one of the treatment options for achieving and preserving weight loss and managing medical complications related to obesity. After bariatric surgery, early or late adverse events, such as intraluminal or extraluminal gastrointestinal hemorrhage, can occur. Early gastrointestinal bleeding is more often a complication associated with Roux-en-Y gastric bypass surgery than other bariatric procedures and usually arises from the gastrojejunal anastomosis. Early postoperative bleeding may be potentially life threatening, although death after postbariatric surgery as a consequence of acute bleeding is uncommon. Although early postoperative intraluminal bleeding can usually be managed conservatively, endoscopic therapy may be required., (Copyright © 2011 Elsevier Inc. All rights reserved.) more...

The surgical management of gallstone ileus is complex and potentially highly morbid. Initial management requires enterolithotomy and is generally followed by fistula resection at a later date. There have been reports of gallstone extraction using various endoscopic modalities to relieve the obstruction, however, to date, there has never been a published case of endoscopic stone extraction from the colon using electrohydraulic lithotripsy. In this report, we present the technique employed to successfully perform an electrohydraulic lithotripsy for removal of a large gallstone impacted in the sigmoid colon. A cavity was excavated in an obstructing 4.1 cm lamellated stone in the sigmoid colon using electrohydraulic lithotripsy. A screw stent retractor and stent extractor bored a larger lumen which allowed for guidewire advancement and stone fracture via serial pneumatic balloon dilatation. The stone fragments were removed. Electrohydraulic lithotripsy is a safe and effective method to treat colonic obstruction in the setting of gallstone ileus. more...

Although acute hypertensive pulmonary edema is sometimes regarded as the most severe form of heart failure, at the peak of symptoms, hearts perform well above resting levels and cannot be said to be failing. Another characteristic of the condition, the rapidity of its onset and reversal when properly treated, suggests positive feedback as a causal mechanism. It is proposed that the syndrome results from a feedback loop with increased sympathetic tone as the efferent output, increased pulmonary vascular pressure as the stimulus to increased sympathetic tone, and positive feedback occurring because elevated sympathetic tone constricts systemic veins, thereby transferring blood from peripheral veins to the pulmonary vasculature. Evidence for the proposed mechanism derives from all the empirical treatments that have evolved. All remove blood from the pulmonary circuit, and all but the oldest, bloodletting, do so by transferring blood from the pulmonary circuit to the peripheral veins. more...

IL-27 exerts antitumor activity in murine orthotopic neuroblastoma, but only partial antitumor effect in disseminated disease. This study demonstrates that combined treatment with IL-2 and IL-27 induces potent antitumor activity in disseminated neuroblastoma metastasis. Complete durable tumor regression was achieved in 90% of mice bearing metastatic TBJ-IL-27 tumors treated with IL-2 compared with only 40% of mice bearing TBJ-IL-27 tumors alone and 0% of mice bearing TBJ-FLAG tumors with or without IL-2 treatment. Comparable antitumor effects were achieved by IL-27 protein produced upon hydrodynamic IL-27 plasmid DNA delivery when combined with IL-2. Although delivery of IL-27 alone, or in combination with IL-2, mediated pronounced regression of neuroblastoma metastases in the liver, combined delivery of IL-27 and IL-2 was far more effective than IL-27 alone against bone marrow metastases. Combined exposure to IL-27 produced by tumor and IL-2 synergistically enhances the generation of tumor-specific CTL reactivity. Potentiation of CTL reactivity by IL-27 occurs via mechanisms that appear to be engaged during both the initial sensitization and effector phase. Potent immunologic memory responses are generated in mice cured of their disseminated disease by combined delivery of IL-27 and IL-2, and depletion of CD8(+) ablates the antitumor efficacy of this combination. Moreover, IL-27 delivery can inhibit the expansion of CD4(+)CD25(+)Foxp3(+) regulatory and IL-17-expressing CD4(+) cells that are otherwise observed among tumor-infiltrating lymphocytes from mice treated with IL-2. These studies demonstrate that IL-27 and IL-2 synergistically induce complete tumor regression and long-term survival in mice bearing widely metastatic neuroblastoma tumors. more...

Postnatal decreases in vascular reactivity involve decreases in the thick filament component of myofilament calcium sensitivity, which is measured as the relationship between cytosolic calcium concentration and myosin light chain (MLC20) phosphorylation. The present study tests the hypothesis that downregulation of thick filament reactivity is due to downregulation of myosin light chain kinase (MLCK) activity in adult compared with fetal arteries. Total MLCK activity, calculated as %MLC20 phosphorylated per second in intact arteries during optimal inhibition of myosin light chain phosphatase activity, was significantly less in adult (6.56+/-0.29%) than in fetal preparations (7.39+/-0.53%). In situ MLC20 concentrations (microM) in adult (198+/-28) and fetal arteries (236+/-44) did not differ significantly. In situ MLCK concentrations (microM), however, were significantly greater in adult (8.21+/-0.59) than in fetal arteries (1.83+/-0.13). In situ MLCK activities (ng MLC20 phosphorylated.s(-1).ng MLCK(-1)) were significantly less in adult (0.26+/-0.01) than in fetal arteries (1.52+/-0.11). In contrast, MLCK activities in adult (15.8+/-1.5) and fetal artery homogenates (17.3+/-1.3) were not significantly different. When in situ fractional activation was calculated, adult values (1.72+/-0.17%) were significantly less than fetal values (9.08+/-0.83%). Together, these results indicate that decreased thick filament reactivity in adult compared with fetal ovine carotid arteries is due at least in part to greater MLCK activity in fetal arteries, which in turn cannot be explained by differences in MLCK, MLC20, or calmodulin concentrations. Instead, this difference appears to involve age-related differences in fractional activation of the MLCK enzyme. more...

Background: ERCP is usually performed with the patient in the prone position. Little data exist on ERCP in the supine position, which is considered unsafe in nonintubated patients., Objective: Our purpose was to compare outcomes of ERCP in the prone and supine positions., Design: Retrospective study., Setting: Tertiary care medical center., Patients: All patients undergoing ERCP by one endoscopist over an 18-month period., Main Outcome Measurements: American Society of Anesthesiologists (ASA) score, procedural degree of difficulty, procedural time, success rates, complication rates, effects on oxygen desaturation and hemodynamics, amount of sedation, need for precut sphincterotomy., Results: A total of 649 patients were evaluated, of whom 506 patients were prone and 143 were supine. There were no differences between the groups with regard to sex, procedural time, ASA scores, need for precut sphincterotomy, adverse cardiovascular events, episodes of oxygen desaturation, dose of meperidine or midazolam, or oxygen supplementation. Complete success and complication rates were similar for both groups (90.2% and 11.2% for supine and 92.5% and 9.1% for prone, respectively). Procedural degree of difficulty was significantly higher in the supine group (P < .001). There were no episodes of aspiration in either group and no severe complications., Limitations: Retrospective study, one endoscopist., Conclusions: ERCP performed in nonintubated patients placed supine is often more difficult and may lead to more mild adverse respiratory events than when performed with the patient prone. Supine ERCP is appropriate in certain patients who cannot lie prone (abdominal pain, abdominal distention, ascites, recent abdominal or neck surgery, indwelling percutaneous tubes and need for access during the procedure to indwelling internal/external percutaneous biliary catheters, and in the morbidly obese) with more intensive monitoring in those who are not intubated. more...

Endoscopic biliary sphincterotomy (ES) is the cornerstone of therapeutic endoscopic retrograde cholangiopancreatography (ERCP). Bleeding is one of the most frequent complications following ES. Rates of post-ES bleeding vary widely and its presentation may be immediate (intraprocedural) or several days later. Clinically, bleeding can range from insignificant to life threatening. Most bleeding episodes are managed successfully by conservative measures with or without endoscopic therapy. Endoscopic treatment options include injection, thermal, and mechanical methods-alone or in combination. For refractory cases, angiographic embolization, or surgery, is necessary. Both technical risk factors and patient risk factors contribute to the development of post-ES bleeding. When these risk factors are present, measures can be taken to reduce the risk of bleeding. In this manuscript the literature on post-ES bleeding is reviewed. more...

It has been reported that sensitization of animals to allergens increases both early shortening velocity and myosin light-chain kinase of their airway smooth muscle without increasing force generated by these muscles. Since early shortening sets muscle length for the duration of a contraction, these responses might be expected to produce greater airway obstruction. Here, it is explained how the more rapid early shortening without increased force production is predicted by the 2-stage process of activation followed by contraction posited by the crossbridge theory of contraction when the rate, but not the extent, of activation is increased. The experimental results are reproduced by a simple model in which activation rate is increased 1.6-fold without any other changes in contractile parameters. These results reinforce suggestions that sensitized animals are a model for reactive airway disease. more...

The full functional length range of trachealis muscle was measured to identify a precise reference length and to assess the length changes that the myofilament lattice can accommodate. The initial reference length (L(10%)) was that where rest tension equaled 10% of total force (passive tension plus active force). Total force at this length served as a force reference (F(ref) = 219 +/- 12 kPa, N = 7). Muscles initially adapted at L(10%) for 30-60 min had no rest tension when shortened to <0.9 L(10%). Passive tension rose steeply and linearly with slope 11.2 F(ref)/L(10%) at lengths >1.04 L(10%). Rest tension at 1.1 L(10%) declined by <10% over 1 h. The steep slope and stability of rest tension at long lengths suggest that a parameter of the slope could serve as a precise, reproducible reference length. Active force was nearly constant at lengths 0.33-1.0 L(10%) and declined steeply at lengths between 0.1 and 0.2 L(10%), extrapolating to zero at 0.076 L(10%). Muscles visibly reextended during relaxation at lengths <0.25 L(10%). At long lengths, force extrapolated to zero at 1.175 L(10%). The >15-fold length range (0.076-1.175 L(10%)) for force generation and nearly constant force over a greater than threefold length range is likely produced by several structural accommodations, including filament sliding, an increased number of sliding filaments in series, and increased length of passive structures in series with the sliding filaments. Visible reextension during relaxation suggests that the lattice does not undergo plastic adaptations at lengths <25% L(10%) and that lattice plasticity is limited to a three- to fourfold length range. more...

Muscle birefringence, caused mainly by parallel thick filaments, increases in smooth muscle during stimulation, signalling thick filament formation upon activation. The reverse occurs in skeletal muscle, where a decrease in birefringence has been correlated with crossbridge movement away from the thick filaments. When force generation by trachealis muscle was inhibited with wortmannin, which inhibits myosin light-chain phosphorylation and thick-filament formation, but not the calcium increase caused by stimulation, the birefringence response inverted, suggesting crossbridge movement similar to that of skeletal muscle. Resistance to quick stretches was much greater in stimulated muscle than in unstimulated muscle before wortmannin treatment and no different in stimulated and unstimulated muscle after force inhibition by wortmannin. Before wortmannin treatment, stimulation reduced thick-filament cross-sectional areas in electron micrographs by 44%. After force inhibition by wortmannin, filament areas were not significantly different in stimulated and unstimulated muscle and not significantly different from those of relaxed muscle without wortmannin treatment. These results suggest that myofibrillar-space calcium causes crossbridges to move away from the thick filaments without firmly attaching to thin filaments. more...

Human neuroblastomas possess several mechanisms of self-defense that may confer an ability to resist apoptosis and contribute to the observed difficulty in treating these tumors in the clinical setting. These molecular alterations may include defects in proapoptotic genes as well as the overexpression of prosurvival factors, such as Akt among others. As a key regulator of the turnover of proteins that modulate the cell cycle and mechanisms of apoptosis, the proteasome could serve as an important target for the treatment of neuroblastoma. The present studies provide the first evidence that bortezomib, a newly approved inhibitor of proteasome function, inhibits phosphorylation of Akt, induces the translocation of proapoptotic Bid, and potently enhances the apoptosis of murine neuroblastoma tumor cells in vitro. Furthermore, in that inhibitors of the Akt pathway can sensitize otherwise resistant TBJ/Neuro-2a cells to apoptosis induced by IFN-gamma plus TNF-alpha, we hypothesized that bortezomib also could sensitize these cells to IFN-gamma plus TNF-alpha. We demonstrate for the first time that bortezomib not only up-regulates the expression of receptors for IFN-gamma and TNF-alpha on both TBJ neuroblastoma and EOMA endothelial cell lines, but also markedly enhances the sensitivity of these cells to apoptosis induced by IFN-gamma plus TNF-alpha in vitro. Furthermore, bortezomib enhances the in vivo antitumor efficacy of IFN-gamma/TNF-alpha-inducing cytokines, including both IL-2 and IL-12 in mice bearing well-established primary and/or metastatic TBJ neuroblastoma tumors. Collectively, these studies suggest that bortezomib could be used therapeutically to enhance the proapoptotic and overall antitumor activity of systemic cytokine therapy in children with advanced neuroblastoma. more...

Throughout August and September, 2003, wildfires burned in close proximity to Missoula, Montana, with smoke emanating from the fires impacting the valley for much of the summer. This presented the perfect opportunity to measure the levels of polychlorinated dibenzodioxins and dibenzofurans (PCDD/F) comprising ambient forest fire smoke particles impacting the Missoula Valley. An air sampler at the Montana Department of Environmental Quality's (DEQ) compliance site in Missoula measured hourly averages of PM(10) throughout the fire season. Three collocated PM(2.5) cyclones collected 24-h smoke samples using quartz filters and Polyurethane Foam (PUF) sorbent cartridges. From the quartz filters, concentrations of Organic and Elemental Carbon (OC/EC) were measured, while PCDD/F were measured from one set of a filter (particle phase) and PUF (vapor phase) aggregate of samples in an attempt to also investigate the different phases of PCDD/F in forest fire smoke impaired communities. Hourly PM(10) concentrations peaked at 302.9 microg m(-3) on August 15. The highest OC concentration (115.6 microg m(-3)) was measured between August 21-22, and the highest EC concentration of 10.5 microg m(-3) was measured August 20-21. Measurable concentrations of PM(2.5) associated PCDD/Fs were not detected from a representative aggregate sample, with the exception of small amounts of 1,2,3,4,6,7,8-heptachlorodibenzodioxin and octachlorodibenzodioxin. PM(2.5) samples collected during the smoke events were composed of approximately 65% OC. However, the OC fraction of the particles collected in the smoke impaired Missoula valley was not composed of significant amounts of PCDD/F. more...

Background: Patients face difficulty selecting physicians because they have little knowledge of how physicians' behaviors fit with their own preferences., Objective: To develop scales of patient and physician behavior preferences and determine whether patient-physician fit is associated with patient satisfaction., Design: Two cross-sectional surveys of patients and providers., Setting: Ambulatory clinics at a university medical center. Participants. Eight general internists, 14 family physicians, and 193 patients., Measurements: Two instruments were developed to measure 6 preferences for physician behaviors: 1) considering nonmedical aspects of the patient's life, 2) familiarity with herbal medicine, 3) physician decision making, 4) providing information, 5) considering the patient's religion, and 6) treating what the patient perceives as his or her problem. Patients reported how they would prefer physicians to behave, and physicians reported how they preferred to behave. Patients also rated satisfaction with their physician., Results: Post hoc tests found that as a group, patients scored higher than physicians in preference for the physician to provide information and lower in preference for considering nonmedical aspects of the patient's life and religious beliefs. As hypothesized, preference differences accounted for significant variance in satisfaction in overall tests (19% in the family medicine patients and 25% in internal medicine patients). Greater satisfaction was associated with fit between patient and physician preferences for physician decision making (in the internal medicine patients) and with fit in providing information and consideration of religion (in family medicine patients), Conclusions: Patients often prefer behaviors other than how their physicians prefer to behave. Preference fit is associated with enhanced patient satisfaction. Physicians should attend to whether patients want religion and other nonmedical aspects of their lives considered. Health plans may wish to provide tools to help patients choose physicians by fit. more...

Neuroblastoma is one of the most common solid tumors in children. The prognosis of patients with advanced neuroblastoma is poor overall despite standard therapeutic modalities and has stimulated substantial interest in the potential role for biologics such as immunotherapeutic and/or antiangiogenic agents for the treatment of neuroblastoma. To facilitate preclinical investigation of the efficacy and mechanisms of action of new biologic agents for the treatment of neuroblastoma, a comprehensive panel of disease-specific fluorescence-based model systems has been developed by our group to image the growth, neovascularization, metastasis, and apoptosis of neuroblastoma tumors. These model systems use fluorescent proteins to monitor cytokine-induced alterations in the growth and metastasis of neuroblastoma and allow for monitoring and/or quantitation of even minimal residual disease that is localized to visceral organ sites such as the liver, lung, and/or bone marrow. Further, based on the differential spectra of red fluorescent protein, green fluorescent protein (GFP), and agents such as 4'-6-diamidino-2-phenylindole (DAPI) (blue) and fluorescein isothiocyanate-dextran (green), multicolor systems have now been established by our group that allow for combined assessment of parameters, including the macroscopic relation of tumors to their associated vasculature and, within tissue sections, simultaneous quantitation of tumor neovascularization and evaluation of therapy-induced apoptosis within the tumor and vascular endothelial compartments. Further, by engineering cells to express specific mediators of apoptosis that have been linked to GFP (ie, BID-EGFP), these systems can also be used to dissect mechanisms by which neuroblastoma cells are induced to undergo apoptosis in vitro as well as in vivo. Collectively, these model systems provide important tools for investigation of the biology of neuroblastoma tumors and evaluation of mechanisms that mediate the regression of these tumors in response to novel therapeutic agents, including cytokines such as interleukin-12. more...

Background: Patients with advanced neuroblastoma have a poor prognosis. The antiapoptotic protein Akt has been implicated as a possible mediator of the resistance of human neuroblastoma cells to apoptosis; the proapoptotic protein Bid, is inhibited by activated Akt. Neuroblastoma has demonstrated responsiveness to immunotherapeutic approaches in preclinical studies, prompting investigation of new therapeutic strategies based on potentiation of the host immune response, including the use of systemic cytokines., Methods: We examined the antitumor efficacy and mechanisms of action of the central immunoregulatory cytokine interleukin-12 (IL-12) in mice bearing established orthotopic neuroblastoma tumors derived from murine TBJ and Neuro-2a cells. Cohorts of mice (10 mice/group) bearing established orthotopic neuroblastoma tumors were injected intraperitoneally with IL-12 or vehicle and monitored for survival. IL-12-induced apoptosis within the tumor microenvironment was investigated using ribonuclease protection assays, nuclear staining, and electron microscopy. Protein expression was determined via Western blot analysis and enzyme-linked immunosorbent assays. Confocal microscopy was used to examine the distribution of overexpressed Bid-enhanced green fluorescent protein fusion protein (Bid-EGFP) in TBJ cells. All statistical tests were two-sided., Results: IL-12 induced complete tumor regression and long-term survival of 8 (80%) of 10 mice bearing established neuroblastoma tumors compared with 1 (10%) of 10 control mice (P = .0055) and profound tumor cell apoptosis in vivo despite the fact that TBJ and Neuro-2a cells were resistant to receptor-mediated apoptosis in vitro. These cells expressed high levels of phosphorylated Akt, a key prosurvival molecule, and Akt inhibitors sensitized neuroblastoma cells to apoptosis mediated by IL-12-inducible cytokines including tumor necrosis factor-alpha and interferon-gamma in vitro. IL-12 increased the expression of proapoptotic genes and decreased Akt phosphorylation within established TBJ tumors in conjunction with activation and subcellular translocation of Bid., Conclusions: Our results suggest that IL-12 overcomes a potentially critical mechanism of tumor self-defense in vivo by inhibiting Akt activity and imply that IL-12 may possess unique therapeutic activity against tumors that express high levels of activated Akt. more...

At a similar meeting 10 years ago, we proposed (i) that the long functional range of some smooth muscles is accommodated by plastic alterations that place more myofilaments in series at longer lengths, (ii) that this plasticity is facilitated by myosin filament evanescence, with filaments dissociating partially during relaxation and reforming upon activation, and (iii) that filament lengthening during the rise of activation would cause velocity to fall. Since that meeting, we have accumulated a substantial body of evidence to support these proposals, as follows: (i) muscles develop nearly the same force when adapted to a range of lengths that can vary by 3-fold; (ii) other physiological parameters including shortening velocity, maximum power, compliance, ATPase rate, and thick-filament mass increase by about 2/3 for a doubling of muscle length; (iii) thick-filament density increases substantially during the rise of activation; and (iv) velocity falls as force rises during the rise of tetanic force, and when correction is made for differences in activation, velocity and force vary exactly in inverse proportion. This review explains the rationale for the different experimental measurements and their interpretation. more...

Researchers have frequently relied on case identification using clinician-based screening as the standard. This study evaluates a self-administered screening questionnaire developed for use in the Veterans Health Study. We compared concordance between elderly patients' reports of selected chronic illnesses and the medical record. The purpose of this study was to determine the feasibility of using a self-report screening questionnaire for case identification in an outcomes study of elderly respondents. Reports of the presence of selected chronic illnesses were compared in a sample of patients (N=402) receiving outpatient care between 2 data sources, patient self-report and medical record, to determine overall concordance in 5 common chronic conditions (hypertension, adult-onset diabetes mellitus, chronic low-back pain, osteoarthritis of the knee, and chronic lung disease). Discordance between the 2 data sources varied by condition. Differences in reporting were small for diabetes and hypertension, intermediate for chronic lung disease, and larger for osteoarthritis of the knee and chronic low-back pain, where the chart did not identify substantial proportions of cases reported in the questionnaire. Use of patient-reported screening questionnaires, which are self-administered, is a valid, cost-efficient method to identify some chronic illnesses. Using medical records alone may result in underestimation of some symptom-based conditions. more...

Measures of case mix are needed to control for patients' clinical status in studies assessing the process and outcomes of care. The Veterans Health Study (VHS) is a longitudinal study of determinants of health outcomes in ambulatory veterans. This study assessed the validity of a case-mix measure developed to quantify severity of illness in ambulatory type 2 diabetic patients. As part of the pilot phase of the VHS, 245 veterans using 4 primary care clinics in Boston were screened for diabetes and 5 other chronic illnesses when they presented for care. Subjects screening positive for diabetes returned to complete severity of illness and outcome measures. The variables for the diabetes case-mix module were chosen based upon the principles of parsimony, duration of follow-up, and clinical validity and credibility. Variables were selected to predict function, as measured by the Medical Outcomes Study Short-Form 36 (SF-36). The diabetic patients in this study had a heavy burden of chronic illness, with an average of 3.9 comorbid conditions and a mean general health perceptions score of 48 on the SF-36 (scored from 0 to 100, with 100 indicating best health). A summary variable called DMSEV was created for "diabetes severity". This included atherosclerotic complications(stroke, transient ischemic attack or myocardial infarction; chest pain frequency; and claudication), plus any history of eye, foot, or neuropathic symptoms. DMSEV correlated with all 8 outcome scales of the SF-36, and in particular was highly associated with physical function (r=0.49, P=.0001). Least squares linear regression analysis controlling for age and comorbidity confirmed the association of DMSEV with all 8 SF-36 scales. The correlation with physical function remained highly significant (P<.0001), with an R of 0.31. This patient-based self-assessment questionnaire and the summary variable DMSEV appear to be valid measures of severity of illness in ambulatory diabetic veterans with multiple comorbidities. After further testing, this case-mix measure may be suitable for controlling for severity of illness in ambulatory-based studies of diabetic patients with multiple chronic illnesses. more...

Birefringence and force produced by pig tracheal smooth muscles were recorded every 100 ms during electrically stimulated tetani at muscle lengths that varied 1.5-fold and at the peak of acetylcholine contractures at the same lengths. Isometric force was nearly the same at all lengths. Resting birefringence at the longest length was 30% greater than that at the shortest length. During tetani, birefringence increased with approximately the same time course as force, rising by 20% at the shortest length and 9% at the longest length, and continued to increase by an additional 0.5-1.5% of the resting value for 2-8 s after stimulation ended and force began to fall. This late increase was greatest and more sustained at longer lengths. During contractures, birefringence increased by 25 and 18% at the shortest and longest lengths, respectively. Comparison of these results with our published thick-filament densities suggests that thick-filament density increased by about 80, 72 and 50% during contractures at the short, intermediate and long lengths, and that approximately 35% of birefringence in the resting muscle at the longest length was not due to thick filaments. These findings support the hypotheses that tracheal smooth muscle adapts to longer lengths by increasing thick-filament mass and that myosin thick filaments are evanescent, dissociating partially during relaxation and reforming upon activation. The results further suggest that thick-filament formation is sufficiently rapid to account for the velocity slowing and some of the force increase observed during the rise of activation of tracheal smooth muscle. more...

We have shown previously that IFN-gamma-inducing cytokines such as IL-12 can mediate potent antitumor effects against murine solid tumors. IL-27 is a newly described IL-12-related cytokine that potentiates various aspects of T and/or NK cell function. We hypothesized that IL-27 might also mediate potent antitumor activity in vivo. TBJ neuroblastoma cells engineered to overexpress IL-27 demonstrated markedly delayed growth compared with control mice, and complete durable tumor regression was observed in >90% of mice bearing either s.c. or orthotopic intra-adrenal tumors, and 40% of mice bearing induced metastatic disease. The majority of mice cured of their original TBJ-IL-27 tumors were resistant to tumor rechallenge. Furthermore, TBJ-IL-27 tumors were heavily infiltrated by CD8(+) T cells, and draining lymph node-derived lymphocytes from mice bearing s.c. TBJ-IL-27 tumors are primed to proliferate more readily when cultured ex vivo with anti-CD3/anti-CD28 compared with lymphocytes from mice bearing control tumors, and to secrete higher levels of IFN-gamma. In addition, marked enhancement of local IFN-gamma gene expression and potent up-regulation of cell surface MHC class I expression are noted within TBJ-IL-27 tumors compared with control tumors. Functionally, these alterations occur in conjunction with the generation of tumor-specific CTL reactivity in mice bearing TBJ-IL-27 tumors, and the induction of tumor regression via mechanisms that are critically dependent on CD8(+), but not CD4(+) T cells or NK cells. Collectively, these studies suggest that IL-27 could be used therapeutically to potentiate the host antitumor immune response in patients with malignancy. more...

To assess activation mechanisms of dog trachealis muscle and test whether isometric force generation could be separated from myosin light-chain (MLC) phosphorylation, force and phosphorylation were measured in the presence of wortmannin (a light-chain kinase inhibitor) or Y-27632 (a rho-kinase inhibitor) during electrically stimulated tetani and sustained contractures induced by acetylcholine, KCl, or calyculin A, a light-chain phosphatase inhibitor which caused irreversible contractures and both di- and mono-phosphorylation of light chain. Phosphorylation was not much more than half under any circumstances. A nearly constant proportionality between steady force and phosphorylation existed over a 9-fold force range during contractures and 25-sec tetani, except that force correlated best with the di-phosphorylated light chain produced by calyculin A. Phosphorylation was disproportionately higher than force at the outset of tetani, and this disproportion was exaggerated by Y-27632. The results suggest that about half the light chain is sequestered from kinases and that mechanical activation is tightly linked to phosphorylation, except at the outset of stimulation. more...

Airway smooth muscle is able to adapt and maintain a nearly constant maximal force generation over a large length range. This implies that a fixed filament lattice such as that found in striated muscle may not exist in this tissue and that plastic remodeling of its contractile and cytoskeletal filaments may be involved in the process of length adaptation that optimizes contractile filament overlap. Here, we show that isometric force produced by airway smooth muscle is independent of muscle length over a twofold length change; cell cross-sectional area was inversely proportional to cell length, implying that the cell volume was conserved at different lengths; shortening velocity and myosin filament density varied similarly to length change: increased by 69.4% +/- 5.7 (SE) and 76.0% +/- 9.8, respectively, for a 100% increase in cell length. Muscle power output, ATPase rate, and myosin filament density also have the same dependence on muscle cell length: increased by 35.4% +/- 6.7, 34.6% +/- 3.4, and 35.6% +/- 10.6, respectively, for a 50% increase in cell length. The data can be explained by a model in which additional contractile units containing myosin filaments are formed and placed in series with existing contractile units when the muscle is adapted at a longer length. more...