Interim Analysis of DD3: A Phase IB/II Trial of Dose-Deescalated 3-Fraction SBRT for Centrally Located Lung Cancer

PURPOSE/OBJECTIVE(S)

Prior studies suggested excessive toxicity for central lung tumors treated with 3-fraction stereotactic body radiation therapy (SBRT). This may be related to the high biologically equivalent dose assuming alpha/beta of 10 (BED) of 54 Gy in 3 fractions (BED = 151.2), as 50-60 Gy in 5 fractions (BED = 100.0-132.0) was well-tolerated in RTOG 0813. We initiated a prospective phase IB/II trial to test the hypothesis that a dose-deescalated regimen of 45 Gy in 3 fractions (BED 112.5) would be safe and efficacious in central lung tumors.

MATERIALS/METHODS

We enrolled patients with primary or secondary lung tumors ≤5cm in a central but not ultra-central tumor location defined as within 2 cm of (but not abutting) tracheobronchial tree, esophagus, or heart. Patients were either medically inoperable or refused surgical intervention. Co-primary endpoints were safety and efficacy, defined as local control (LC). Secondary endpoints included lobar control, regional control (LRC), distant control (DC), progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS). Organ-at-risk dose constraints were consistent with those of RTOG 0236. The Bayesian predictive probability approach was utilized for continuous monitoring after 10 patients were treated and have mature assessment of toxicity, after which interim analysis was planned. We recommended terminating the trial for safety if there was sufficient evidence that the rate of grade ≥3 was greater than 0.25 (predictive probability >0.80).

RESULTS

As of the data cut-off date of 1/26/23, the trial was open for 34 months (including a nearly-immediate suspension due to the COVID-19 pandemic). A total of 17 patients have been treated on protocol with a median follow-up of 12 months. No grade ≥3 adverse events attributable to SBRT have occurred to date, though one patient died of unrelated cardiac arrhythmias 1 month after SBRT completion (Table 1). Maximum CTCAE grade 2 adverse events attributable to SBRT occurred in 17.6% of patients. The predictive probability of concluding unacceptably high toxicity rate by the end of the trial based on toxicity data in the current stage is 0.62%. To date, there have been 0 local recurrences, 1 regional recurrence without local recurrence (8 months after SBRT completion, successfully salvaged with definitive chemoradiotherapy without additional toxicities), and 1 distant recurrence without local recurrence (6 months after SBRT in a patient with lung metastasis from colon adenocarcinoma).

CONCLUSION

Interim analysis of the DD3 trial suggests that for patients with central but not ultra-central lung tumors, an SBRT regimen of 45 Gy in 3 fractions warrants continued trial accrual and follow-up given no grade ≥3 toxicities or local recurrences in the early follow-up period among the first 17 patients enrolled.

Dose-Escalated vs. Conventional Hypofractionated Radiotherapy for Lung Cancer Patients in Predominantly Central Locations

PURPOSE/OBJECTIVE(S)

Hypofractionated radiation therapy (HFRT) is an increasingly utilized treatment option for patients with lung cancers unamenable to stereotactic body radiotherapy (SBRT). Conventional HFRT (C-HFRT) is often prescribed to 60 Gy in 15 fractions, which has a lower biologically effective dose (BED10 of 84.0) than SBRT. We compared outcomes of patients treated with a dose-escalated HFRT regimen (DE-HFRT, 72 Gy in 18 fractions, BED10 of 100.8) to those treated with C-HFRT. We aimed to evaluate local control (LC), overall survival (OS), and grade 3+ toxicity between patients who received C-HFRT vs. DE-HFRT as we hypothesized DE-HFRT may be superior/equivalent to C-HFRT.

MATERIALS/METHODS

A database was created of all patients at our institution who received either thoracic C-HFRT or DE-HFRT between 2013 and 2020. Baseline variables were compared by chi-square analysis and logistic regression. We analyzed the association between treatment regimens with LC and OS (log-rank test and Cox proportional hazards regression), as well as grade 3+ toxicity.

RESULTS

A total of 107 patients were included, among whom 55 (51.4%) received C-HFRT and 52 (48.6%) received DE-HFRT. Median age was 73, 88.8% of patients had non-small cell lung cancer, 81.3% received lung-only treatment, and 52.3% had an ultra-central tumor location (within 1 cm of proximal tracheobronchial tree, esophagus, or heart). Patients with DE-HFRT were more likely to have lung-only treatment (92.3% vs. 70.9%, p = 0.005) and stage I disease (47.1% vs 24.1%, p = 0.01) than those with C-HFRT, but had a similar proportion of ultra-central tumors (57.1% vs. 54.9%, p = 0.82). Patients with DE-HFRT had a non-statistically significant trend towards higher LC (2-year 81.0% vs. 72.3%, 3-year 77.3% vs 52.3%, HR 0.53 [95% CI 0.26-1.09], p = 0.09) and OS (2-year 61.3% vs. 44.8%, 3-year 44.9% vs 33.9%, HR 0.68 [95% CI 0.41-1.11], p = 0.13) compared to those with C-HFRT. Similar findings were noted among those with lung-only treatment. Among those with ultra-central tumors, patients with DE-HFRT had statistically significantly higher LC (2-year 86.6% vs 71.2%, 3-year 86.6% vs 42.2%, HR 0.26 [95% CI 0.08-0.84] p = 0.02) and a non-statistically significant trend towards higher OS (2-year 63.8% vs 40.0%, 3-year 46.2% vs 31.1% HR 0.55 [95% CI 0.28-1.09] p = 0.09) compared to those with C-HFRT. There was no statistically significant difference in grade 3+ toxicities between DE-HFRT and C-HFRT (15.4% vs. 10.9%, OR 1.48 [95% CI 0.47-4.61], p = 0.49).

CONCLUSION

We noted promising local control and overall survival for patients treated with 72 Gy in 18 fractions compared to 60 Gy in 15 fractions, especially among those with ultra-central tumors. Grade 3+ toxicities were not significantly higher for patients undergoing dose escalation. Hence, our findings suggest that DE-HFRT to the lung is a safe and effective treatment regimen for highly selected patients who cannot undergo SBRT.

Survival Outcomes for Oligometastatic vs. Polymetastatic Extensive-Stage Small Cell Lung Cancer Following Consolidative Thoracic Radiotherapy

PURPOSE/OBJECTIVE(S)

For patients with limited metastatic burden, metastasis-directed radiotherapy has been shown to be associated with improved OS for certain types of cancer. However, these prior trials did not include patients with ES-SCLC. It is not yet clear if patients with oligometastatic ES-SCLC have improved outcomes over polymetastatic ES-SCLC after cTRT.

MATERIALS/METHODS

We identified patients treated with cTRT for ES-SCLC in 2013-2020 at a single institution. Oligometastatic disease was defined at the time of diagnosis as three or fewer organs with distant disease, and with each organ having three or fewer metastatic lesions. All other patients were considered polymetastatic. The Kaplan-Meier estimator, log-rank test, and multivariable Cox proportional hazards regression were used to compare OS, progression-free survival (PFS), local recurrence-free survival (LRFS), and new metastasis-free survival (NMFS) between oligometastatic and polymetastatic ES-SCLC patients undergoing cTRT.

RESULTS

Among 70 included patients, 36 were defined as oligometastatic. All patients received platinum-doublet chemotherapy and cT. Immunotherapy was given in 7 (19.4%) oligometastatic patients and 5 (14.7%) polymetastatic patients (p = 0.56). Median follow-up time was 38.2 months. Multivariable Cox regression analysis showed that oligometastatic disease (vs. polymetastatic disease) at diagnosis was associated with improved OS (hazard ratio [HR] 0.44, 95% CI 0.25-0.78, p = 0.005, 1-year OS 86.1% vs. 46.9%, 2-year OS 47.1% vs. 15.1%). PFS, LRFS, and NMFS were not significantly different between the cohorts. Among oligometastatic patients, pleural involvement (HR 2.44, 95% CI 1.02-5.83, p = 0.046) and lung involvement (HR 4.93, 95% CI 1.02-23.9, p = 0.047) were associated with inferior OS. Among the 26 of 36 (72.2%) oligometastatic patients with neither pleural nor bilateral lung involvement, 1-year OS was 88.5% and 2-year OS was 58.3%.

CONCLUSION

We observed that oligometastatic ES-SCLC patients treated with cTRT (especially those without pleural or bilateral lung involvement) have superior OS than those with polymetastatic disease. We encourage enrollment on the NRG LU007/RAPTOR randomized trial to determine the impact of complete or incomplete consolidative RT to up to 5 sites in ES-SCLC, especially in those with oligometastatic disease.

Environmental Complexity and Reduced Stocking Density Promote Positive Behavioral Outcomes in Broiler Chickens

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD) or low (LD) density. Through focal-animal sampling, the frequency and duration of behaviors were recorded continuously for 5 min at two timepoints for one day in weeks 2, 4, and 7. Birds were active for 30% of the observed time, with birds showing more activity in HC compared with LC. Birds in HC pens spent more time preening and foraging than birds in LC pens, which was interpreted as a positive outcome. Dustbathing and play were not impacted by complexity, possibly due to the observation method. Birds were more frequently active at HD compared with LD, but did not spend more time being active, suggesting disturbances. Birds foraged, drank, and ate less frequently in HD compared with LD, presumably because birds had more difficulty accessing resources. Activity and active behaviors reduced as birds aged, while preening frequency increased, possibly due to frustration, but this was not confirmed. Perching was unaffected by age, showing a persistent motivation to perform the behavior. Our results indicate that a complex environment provides positive stimulation for foraging, locomotion, preening, and overall activity. Despite reduced activity, many benefits of the tested environmental complexity and low density persisted as birds aged.

Measuring Chronic Stress in Broiler Chickens: Effects of Environmental Complexity and Stocking Density on Immunoglobulin-A Levels

Commercial housing conditions may contribute to chronic negative stress in broiler chickens, reducing their animal welfare. The objective of this study was to determine how secretory (fecal) and plasma immunoglobulin-A (IgA) levels in fast-growing broilers respond to positive and negative housing conditions. In three replicated experiments, male Ross 708 broilers (n = 1650/experiment) were housed in a 2 × 2 factorial study of high or low environmental complexity and high or low stocking density. In experiments 1 and 3 but not in experiment 2, high complexity tended to positively impact day 48 plasma IgA concentrations. When three experiments were combined, high complexity positively impacted day 48 plasma IgA concentrations. Stocking density and the complexity × density interaction did not impact day 48 plasma IgA concentrations. Environmental complexity and the complexity × density interaction did not impact day 48 secretory IgA concentrations. A high stocking density negatively impacted day 48 secretory IgA concentrations overall but not in individual experiments. These results suggest that environmental complexity decreased chronic stress, while a high stocking density increased chronic stress. Thus, plasma IgA levels increased under high-complexity housing conditions (at day 48), and secretory IgA levels (at day 48) decreased under high-density conditions, suggesting that chronic stress differed among treatments. Therefore, these measures may be useful for quantifying chronic stress but only if the statistical power is high. Future research should replicate these findings under similar and different housing conditions to confirm the suitability of IgA as a measure of chronic stress in broiler chickens.

Social-pair judgment bias testing in slow-growing broiler chickens raised in low- or high-complexity environments

Impacts of environmental complexity on affective states in slow-growing broiler chickens (Gallus gallus domesticus) are unknown. Chickens' performance in judgment bias tests (JBT) can be limited as they are tested individually, causing fear and anxiety. The objectives were to apply a social-pair JBT to assess the effect of environmental complexity on slow-growing broiler chickens` affective states, and assess the impact of fearfulness, anxiety, and chronic stress on JBT performance. Six-hundred Hubbard Redbro broilers were housed in six low-complexity (similar to commercial) or six high-complexity (permanent and temporary enrichments) pens. Twelve chicken pairs were trained (1 pair/pen, n = 24 chickens) using a multimodal approach (visual and spatial cues), with reward and neutral cues of opposing color and location. Three ambiguous cues were tested: near-positive, middle, and near-neutral cues. Approach and pecking behavior were recorded. Eighty-three percent of chickens (20/24) were successfully trained in 13 days. Fearfulness, anxiety, and chronic stress did not impact chickens' performance. Chickens successfully discriminated between cues. Low-complexity chickens approached the middle cue faster than high-complexity chickens, indicating that they were in a more positive affective state. The environmental complexity provided in this study did not improve affective states in slow-growing broiler chickens compared to a control. A social-pair JBT resulted in excellent learning and testing outcomes in slow-growing broilers.

Effects of Housing System on Anxiety, Chronic Stress, Fear, and Immune Function in Bovan Brown Laying Hens

The scientific community needs objective measures to appropriately assess animal welfare. The study objective was to assess the impact of housing system on novel physiological and behavioral measurements of animal welfare for laying hens, including secretory and plasma Immunoglobulin (IgA; immune function), feather corticosterone (chronic stress), and attention bias testing (ABT; anxiety), in addition to the well-validated tonic immobility test (TI; fearfulness). To test this, 184 Bovan brown hens were housed in 28 conventional cages (3 birds/cage) and 4 enriched pens (25 birds/pen). Feces, blood, and feathers were collected 4 times between week 22 and 43 to quantify secretory and plasma IgA and feather corticosterone concentrations. TI tests and ABT were performed once. Hens that were from cages tended to show longer TI, had increased feather corticosterone, and decreased secretory IgA at 22 weeks of age. The caged hens fed quicker, and more hens fed during the ABT compared to the penned hens. Hens that were in conventional cages showed somewhat poorer welfare outcomes than the hens in enriched pens, as indicated by increased chronic stress, decreased immune function at 22 weeks of age but no other ages, somewhat increased fear, but reduced anxiety. Overall, these novel markers show some appropriate contrast between housing treatments and may be useful in an animal welfare assessment context for laying hens. More research is needed to confirm these findings.

Effect of Environmental Complexity and Stocking Density on Fear and Anxiety in Broiler Chickens

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers' attention bias (measure of anxiety) and tonic immobility (measure of fear). In Experiment 1, individual birds were tested for attention bias (n = 60) and in Experiment 2, groups of three birds were tested (n = 144). Tonic immobility testing was performed on days 12 and 26 (n = 36) in Experiment 1, and on day 19 (n = 72) in Experiment 2. In Experiment 1, no differences were observed in the attention bias test. In Experiment 2, birds from high-complexity pens began feeding faster and more birds resumed feeding than from low-complexity pens following playback of an alarm call, suggesting that birds housed in the complex environment were less anxious. Furthermore, birds housed in high-density or high-complexity pens had shorter tonic immobility durations on day 12 compared to day 26 in Experiment 1. In Experiment 2, birds from high-density pens had shorter tonic immobility durations than birds housed in low-density pens, which is contrary to expectations. Our results suggest that birds at 3 weeks of age were less fearful under high stocking density conditions than low density conditions. In addition, results indicated that the complex environment improved welfare of broilers through reduced anxiety.

Improving prevention of family violence during (and after) disaster: Lessons learned from the Covid-19 pandemic

As feared by many, our dedicated actions to slow the spread of COVID-19 significantly impacted reporting for most forms of family violence. This concerning decline in reports was greatest during periods of lockdown, when risk of abuse was likely at its highest. A new theory termed, Opportunity to Abuse Theory, helps explain why family violence increased during the Covid-19 pandemic and after most prior natural disasters. The theory focuses on reducing opportunity to abuse by reducing victim vulnerability and increasing perpetrator accountability. Additional actions to improve detection of and reduce risk for family violence, such as improving partnerships with animal welfare organizations (animal abuse reporting was not as impacted during lockdown), enlisting the aid of non-traditional family violence report sources, better utilizing hotels to provide safety when shelter space is limited, and ensuring texting options for reporting abuse, must be considered during and after disaster.

Intimate Partner Violence and Pet Abuse: Responding Law Enforcement Officers' Observations and Victim Reports From the Scene

The risk of harm/injury in homes where intimate partner violence (IPV) occurs is not limited to humans; animals reside in as many as 80% of these homes and may be at substantial risk of suffering severe or fatal injury. Gaining a better understanding of IPV-pet abuse overlap is imperative in more accurately identifying the risks of harm for all individuals and animals residing in these homes. The objectives of this study were to utilize law enforcement officers' observations and IPV victim reports from the scene of the incident to (a) determine the prevalence of pet abuse perpetration among suspects involved in IPV incidents, (b) compare characteristics of IPV incidents and the home environments in which they occur when the suspect has a history of pet abuse with incidents involving suspects with no reported history of pet abuse, and (c) compare IPV incident outcomes involving suspects with a history of pet abuse with those involving suspects with no reported history of pet abuse. IPV victims residing in homes with a suspect who has a history of pet abuse often describe "extremely high-risk" environments. With nearly 80% reporting concern that they will eventually be killed by the suspect, victims in these environments should be considered at significant risk of suffering serious injury or death. In addition, IPV victims involved in incidents with a suspect that has a history of pet abuse were significantly more likely to have had at least one prior unreported IPV incident with the suspect (80%) and to have ever been strangled (76%) or forced to have sex with the suspect (26%). Effective prevention/detection/intervention strategies are likely to require multidisciplinary collaboration and safety plans that address the susbstantial risk of harm/injury for all adults, children, and animals residing in the home.

An increasing risk of family violence during the Covid-19 pandemic: Strengthening community collaborations to save lives

Though necessary to slow the spread of the novel Coronavirus (Covid-19), actions such as social-distancing, sheltering in-place, restricted travel, and closures of key community foundations are likely to dramatically increase the risk for family violence around the globe. In fact many countries are already indicating a dramatic increase in reported cases of domestic violence. While no clear precedent for the current crisis exists in academic literature, exploring the impact of natural disasters on family violence reports may provide important insight for family violence victim-serving professionals. Improving collaborations between human welfare and animal welfare agencies, expanding community partnerships, and informing the public of the great importance of reporting any concerns of abuse are all critical at this time.

Characteristics of Intimate Partner Violence Incidents and the Environments in Which They Occur: Victim Reports to Responding Law Enforcement Officers

The objectives of this study were to identify intimate partner violence (IPV) incidence rates, to quantify specific risks and characteristics of these incidents and the environments in which they occur, to identify how often children are present for or injured during these incidents, and to identify differences in victim reports of IPV to law enforcement officers at the scene of the incident compared with previously published reports of IPV from retropsective, anonymous surveys and domestic violence shelter interviews. Data gathered by responding law enforcement officers at the scene of the IPV incident were used to determine the prevalence of IPV incident characteristics and outcomes. Females aged 20 to 39 years, unmarried adults, and African Americans were disproportionately represented as victims of IPV in this study. IPV incidents were significantly more likely to occur on Saturdays and Sundays and during the months of May through August. Relationship durations for suspect-victim pairs were most often less than 12 months at the time of the incident. Weapon use and/or strangulation was common, occurring in 44% of all incidents. Minors (under age 18 years) were frequently present in the home during the IPV incident or a member of the household (59%). This study provides a unique perspective of IPV by utilizing data collected directly from the scene of the incident by first responders. Previously published characteristics of IPV were confirmed, but this study also brings to light new and critical information concerning this prevalent form of violence. Study findings relating to incidence, seasonality, severity, disproportionately affected populations, and child exposure are discussed.

Optimization of bioprocess conditions improves production of a CHO cell-derived, bioengineered heparin

Heparin is the most widely used anticoagulant drug in the world today. Heparin is currently produced from animal tissues, primarily porcine intestines. A recent contamination crisis motivated development of a non-animal-derived source of this critical drug. We hypothesized that Chinese hamster ovary (CHO) cells could be metabolically engineered to produce a bioengineered heparin, equivalent to current pharmaceutical heparin. We previously engineered CHO-S cells to overexpress two exogenous enzymes from the heparin/heparan sulfate biosynthetic pathway, increasing the anticoagulant activity ∼100-fold and the heparin/heparan sulfate yield ∼10-fold. Here, we explored the effects of bioprocess parameters on the yield and anticoagulant activity of the bioengineered GAGs. Fed-batch shaker-flask studies using a proprietary, chemically-defined feed, resulted in ∼two-fold increase in integrated viable cell density and a 70% increase in specific productivity, resulting in nearly three-fold increase in product titer. Transferring the process to a stirred-tank bioreactor increased the productivity further, yielding a final product concentration of ∼90 μg/mL. Unfortunately, the product composition still differs from pharmaceutical heparin, suggesting that additional metabolic engineering will be required. However, these studies clearly demonstrate bioprocess optimization, in parallel with metabolic engineering refinements, will play a substantial role in developing a bioengineered heparin to replace the current animal-derived drug.

More than words: the emotional maltreatment of children

Emotional maltreatment may be the most complex, prevalent, and damaging form of child maltreatment and can occur simultaneously with other forms of abuse. Children in the first few years of life seem to be at the greatest risk of suffering the most negative outcomes. Medical professionals can help identify and protect victims of emotional maltreatment by carefully observing caregiver-child interactions, paying attention to a family's social history, making referrals to community or counseling programs when necessary, and reporting any suspicions of maltreatment to Child Protective Services. A well-coordinated, multidisciplinary response must be enacted whenever emotional maltreatment is suspected or reported.

Serum-free spheroid suspension culture maintains mesenchymal stem cell proliferation and differentiation potential

There have been many clinical trials recently using ex vivo-expanded human mesenchymal stem cells (MSCs) to treat several disease states such as graft-versus-host disease, acute myocardial infarction, Crohn's disease, and multiple sclerosis. The use of MSCs for therapy is expected to become more prevalent as clinical progress is demonstrated. However, the conventional 2-dimensional (2D) culture of MSCs is laborious and limited in scale potential. The large dosage requirement for many of the MSC-based indications further exacerbates this manufacturing challenge. In contrast, expanding MSCs as spheroids does not require a cell attachment surface and is amenable to large-scale suspension cell culture techniques, such as stirred-tank bioreactors. In the present study, we developed and optimized serum-free media for culturing MSC spheroids. We used Design of Experiment (DoE)-based strategies to systematically evaluate media mixtures and a panel of different components for effects on cell proliferation. The optimization yielded two prototype serum-free media that enabled MSCs to form aggregates and proliferate in both static and dynamic cultures. MSCs from spheroid cultures exhibited the expected immunophenotype (CD73, CD90, and CD105) and demonstrated similar or enhanced differentiation potential toward all three lineages (osteogenic, chondrogenic, adipogenic) as compared with serum-containing adherent MSC cultures. Our results suggest that serum-free media for MSC spheroids may pave the way for scale-up production of MSCs in clinically relevant manufacturing platforms such as stirred tank bioreactors.

Serum-free spheroid suspension culture maintains mesenchymal stem cell proliferation and differentiation potential

There have been many clinical trials recently using ex vivo-expanded human mesenchymal stem cells (MSCs) to treat several disease states such as graft-versus-host disease, acute myocardial infarction, Crohn's disease, and multiple sclerosis. The use of MSCs for therapy is expected to become more prevalent as clinical progress is demonstrated. However, the conventional 2-dimensional (2D) culture of MSCs is laborious and limited in scale potential. The large dosage requirement for many of the MSC-based indications further exacerbates this manufacturing challenge. In contrast, expanding MSCs as spheroids does not require a cell attachment surface and is amenable to large-scale suspension cell culture techniques, such as stirred-tank bioreactors. In the present study, we developed and optimized serum-free media for culturing MSC spheroids. We used Design of Experiment (DoE)-based strategies to systematically evaluate media mixtures and a panel of different components for effects on cell proliferation. The optimization yielded two prototype serum-free media that enabled MSCs to form aggregates and proliferate in both static and dynamic cultures. MSCs from spheroid cultures exhibited the expected immunophenotype (CD73, CD90, and CD105) and demonstrated similar or enhanced differentiation potential toward all three lineages (osteogenic, chondrogenic, adipogenic) as compared with serum-containing adherent MSC cultures. Our results suggest that serum-free media for MSC spheroids may pave the way for scale-up production of MSCs in clinically relevant manufacturing platforms such as stirred tank bioreactors.

Outbreak of abdominal distension and obstipation in a C57BL/6J experimental autoimmune encephalomyelitis study

Seventy-four 9-week old female C57BL/6J mice housed in a conventional facility were manipulated to induce experimental autoimmune encephalomyelitis, among which 26 developed clinical signs including lethargy, absence of defecation, and abdominal distension. By gross necropsy examination, there was distension of the cecum and colon with fecal impaction. By histologic examination, there was severe ulcerative and proliferative typhlocolitis. Fecal ELISA confirmed the presence of toxins A and B of Clostridium difficile. Alteration in immune status of the immunocompetent mice, due to stress caused by experimental manipulation or autoimmune disease, may have led to intestinal dysbiosis, followed by opportunistic infections resulting in C. difficile-associated disease. This report brings to light the occurrence of the disease in immunocompetent laboratory mice during experimental manipulations associated with alteration in immune status, and it discusses potential hazards associated with conventional housing within a hospital-associated research institute.

Toward a clinical-grade expansion of mesenchymal stem cells from human sources: a microcarrier-based culture system under xeno-free conditions

The immunomodulatory properties of mesenchymal stem cells (MSCs) make them attractive therapeutic agents for a wide range of diseases. However, the highly demanding cell doses used in MSC clinical trials (up to millions of cells/kg patient) currently require labor intensive methods and incur high reagent costs. Moreover, the use of xenogenic (xeno) serum-containing media represents a risk of contamination and raises safety concerns. Bioreactor systems in combination with novel xeno-free medium formulations represent a viable alternative to reproducibly achieve a safe and reliable MSC doses relevant for cell therapy. The main goal of the present study was to develop a complete xeno-free microcarrier-based culture system for the efficient expansion of human MSC from two different sources, human bone marrow (BM), and adipose tissue. After 14 days of culture in spinner flasks, BM MSC reached a maximum cell density of (2.0±0.2)×10⁵ cells·mL⁻¹ (18±1-fold increase), whereas adipose tissue-derived stem cells expanded to (1.4±0.5)×10⁵ cells·mL⁻¹ (14±7-fold increase). After the expansion, MSC expressed the characteristic markers CD73, CD90, and CD105, whereas negative for CD80 and human leukocyte antigen (HLA)-DR. Expanded cells maintained the ability to differentiate robustly into osteoblast, adipocyte, and chondroblast lineages upon directed differentiation. These results demonstrated the feasibility of expanding human MSC in a scalable microcarrier-based stirred culture system under xeno-free conditions and represent an important step forward for the implementation of a Good Manufacturing Practices-compliant large-scale production system of MSC for cellular therapy.

Vacuum-assisted closure of the open abdomen in a resource-limited setting

AIM

We describe our experience of developing a modified vacuum-assisted closure (VAC) dressing for open abdomens.

BACKGROUND

We see a high volume of trauma in our department. Massive delays in presentation of patients with acute abdomen are common. Closure at initial laparotomy is not possible in many cases, either because the patient has or will develop abdominal compartment syndrome, or because several re-look laparotomies will be required. A significant proportion of our patients who have undergone laparotomy therefore spend some of their stay in hospital with an open abdomen. The management of these patients is particularly labour intensive for nursing staff. The Opsite sandwich or Bogota bag invariably leaks, and sometimes needs changing daily. If a patient also has a temporary ileostomy, application can be difficult. The commercial VAC dressing is an improvement on the Opsite sandwich, but is prohibitively expensive. Financial constraints and the volume of abdominal trauma and sepsis we see mean that commercial VAC dressings for laparostomy are not affordable in our setting.

METHODS/RESULTS

We describe our adapted VAC dressing. It is inexpensive and easy to apply, has made a big difference in the nursing of patients with an open abdomen, and has enabled us to increase the rate of delayed primary closure (i.e., we have reduced the rate of ventral hernia).

CONCLUSION

The modified VAC dressing is now our department's method of choice for temporary abdominal closure.

Calorimetric method of ac loss measurement in a rotating magnetic field

A method is described for calorimetric ac-loss measurements of high-T(c) superconductors (HTS) at 80 K. It is based on a technique used at 4.2 K for conventional superconducting wires that allows an easy loss measurement in parallel or perpendicular external field orientation. This paper focuses on ac loss measurement setup and calibration in a rotating magnetic field. This experimental setup is to demonstrate measuring loss using a temperature rise method under the influence of a rotating magnetic field. The slight temperature increase of the sample in an ac-field is used as a measure of losses. The aim is to simulate the loss in rotating machines using HTS. This is a unique technique to measure total ac loss in HTS at power frequencies. The sample is mounted on to a cold finger extended from a liquid nitrogen heat exchanger (HEX). The thermal insulation between the HEX and sample is provided by a material of low thermal conductivity, and low eddy current heating sample holder in vacuum vessel. A temperature sensor and noninductive heater have been incorporated in the sample holder allowing a rapid sample change. The main part of the data is obtained in the calorimetric measurement is used for calibration. The focus is on the accuracy and calibrations required to predict the actual ac losses in HTS. This setup has the advantage of being able to measure the total ac loss under the influence of a continuous moving field as experienced by any rotating machines.

Does biventricular pacing improve hemodynamics in children undergoing routine congenital heart surgery?

Biventricular (BiV) pacing or cardiac resynchronization therapy (CRT) is an established therapy for heart failure in adults. In children, cardiac dyssynchrony occurs most commonly following repair of congenital heart disease (CHD) where multisite pacing has been shown to improve both hemodynamics and ventricular function. Determining which patient types would specifically benefit has not yet been established. A prospective, repeated measures design was undertaken to evaluate BiV pacing in a cohort of children undergoing biventricular repair for correction of their CHD. Hemodynamics, arterial blood gas, electrocardiographic (ECG), and echocardiographic data were collected. Pacing protocol was undertaken prior to the patient's extubation with 20 min of conventional right ventricular (RV) or BiV pacing, preceded and followed by 10 min of recovery time. Multivariate statistics were used to analyze the data with p values <0.05 considered significant. Twenty-five (14 female) patients underwent surgery at a median (range) age of 5.2 (0.1-37.4) months with no early mortality. The Risk-adjusted classification for Congenital Heart Surgery (RACHS) scores were 2 in 14 patients, 3 in eight patients, and 4 in three patients. None had pre-existing arrhythmias, dyssynchrony, or required pacing pre-operatively. No patient required implantation of a permanent pacemaker post-operatively. The median cardio-pulmonary bypass time was 96 (55-236) min. RV and BiV pacing did not improve cardiac index from baseline (3.23 vs. 3.42 vs. 3.39 L/min/m2; p > 0.05). The QRS duration was not changed with pacing (100 vs. 80 vs. 80 ms; p > 0.05). On echocardiography, the time-to-peak velocity difference between the septal and posterior walls (synchrony) during pacing was similar to baseline and was also not statistically significant. BiV pacing did not improve cardiac output when compared to intrinsic sinus rhythm or RV pacing in this cohort of patients. Our study has shown that BiV pacing is not indicated in children who have undergone routine BiV congenital heart surgery. Further prospective studies are needed to assess the role of multisite pacing in children with ventricular dyssynchrony such as those with single ventricles, those undergoing reoperation or those with high RACHS scores.

The voltage dependent anion channel affects mitochondrial cholesterol distribution and function

We have observed abnormally high membrane cholesterol levels and a subsequent deficiency of oxidative energy production in mitochondria from cultured Morris hepatoma cells (MH7777). Using cholesterol affinity chromatography and MALDI-TOF Mass Spectrometry, we have identified the voltage dependent anion channel (VDAC) as a necessary component of a protein complex involved in mitochondrial membrane cholesterol distribution. VDAC is known to associate strongly with hexokinase, particularly in glycolytic cancers. By constructing an E72Q mutant form of VDAC that inhibits its binding of hexokinase, we report an increase in oxidative phosphorylation activity of MH7777 cells, as well as reduced membrane cholesterol ratios to levels near that of normal liver mitochondria. This paper demonstrates that the ability of VDAC to influence mitochondrial membrane cholesterol distribution may have implications on mitochondrial characteristics such as oxidative phosphorylation and induction of apoptosis, as well as the propensity of cancer cells to exhibit a glycolytic phenotype.

MAGIC Tool: integrated microarray data analysis

SUMMARY

Several programs are now available for analyzing the large datasets arising from cDNA microarray experiments. Most programs are expensive commercial packages or require expensive third party software. Some are freely available to academic researchers, but are limited to one operating system. MicroArray Genome Imaging and Clustering Tool (MAGIC Tool) is an open source program that works on all major platforms, and takes users 'from tiff to gif'. Several unique features of MAGIC Tool are particularly useful for research and teaching.

AVAILABILITY

http://www.bio.davidson.edu/MAGIC

Cattle and environmental sample-level factors associated with the presence of Salmonella in a multi-state study of conventional and organic dairy farms

The objective of this study was to evaluate associations between cattle-level factors and environmental samples with the isolation of Salmonella from dairy farms in Minnesota, Wisconsin, Michigan, and New York. The study farms included 129 conventional and organic farms enrolled without regard to previous history of Salmonella infection. Herds were sampled at two-month intervals over a one-year period. Cattle groups more likely to be associated with Salmonella shedding (compared to preweaned calves) were cows designated as sick by farm personnel (OR=2.5, 95% CI: 1.7, 3.7), cows within 14 days of calving (OR=1.8, 95% CI: 1.1, 2.8), and cows due for culling within 14 days (OR=1.9, 95% CI: 1.0, 3.4). State of origin was also associated with the presence of Salmonella in samples from cattle and the farm environment; Midwestern states were more likely to have Salmonella-positive samples compared to New York. Cattle treated with antimicrobials within 14 days of sampling were more likely to be Salmonella-negative compared with nontreated cattle (OR=2.0, 95% CI: 1.1, 3.4). Farms with at least 100 cows were more likely to have Salmonella-positive cattle compared with smaller farms (OR=2.6, 95% CI: 1.4, 4.6). Season was associated with Salmonella shedding in cattle, and compared to the winter period, summer had the highest odds for shedding (OR=2.4, 95% CI: 1.5, 3.7), followed by fall (OR=1.9, 95% CI: 1.2, 3.1) and spring (OR=1.8, 95% CI: 1.2, 2.6). Environmental samples significantly more likely to be Salmonella-positive (compared to bulk tank milk) included, in descending order, samples from sick pens (OR=7.4, 95% CI: 3.4, 15.8), manure storage areas (OR=6.4, 95% CI: 3.5, 11.7), maternity pens (OR=4.2, 95% CI: 2.2, 8.1), haircoats of cows due to be culled (OR=3.9, 95% CI: 2.2, 7.7), milk filters (OR=3.3, 95% CI: 1.8, 6.0), cow waterers (OR=2.8, 95% CI: 1.4, 5.7), calf pens (OR=2.7, 95% CI: 1.3, 5.3), and bird droppings from cow housing (OR=2.4, 95% CI: 1.3, 4.4). Parity, stage of lactation, and calf age were not associated with Salmonella shedding.

Crystallization and preliminary crystallographic analysis of a new class of glutathione transferase from nematodes

Mouse and Heligmosomoides polygyrus constitute a readily manipulated small-animal laboratory model for investigating host-nematode interactions. Two major forms of glutathione transferase (GST) are expressed in H. polygyrus adult worms following primary infection. One of these forms belongs to a new class of GST which has only been found in the nematode phylum and therefore presents a possible target for nematode control. In this study, crystals were obtained of a recombinant representative of this new GST class from H. polygyrus. These crystals belong to the triclinic space group P1, with unit-cell parameters a = 72.7, b = 74.0, c = 88.6 A, alpha = 79.1, beta = 80.1, gamma = 81.5 degrees, and are likely to contain four homodimers in the asymmetric unit. X-ray diffraction data were collected to 1.8 A resolution on station A1 at the Cornell High-Energy Synchrotron Source (CHESS).

A cholesterol-binding and transporting protein from rat liver mitochondria

In this communication, we present results indicating a protein isolated from rat liver mitochondrial intermembrane space that is capable of binding cholesterol and transporting it between the inner and outer mitochondrial membranes. This protein has a molecular weight of 57.5 kDa by SDS-PAGE; however, under native conditions, there is cholesterol-binding capability only as a 115 kDa dimer. Our data show that this dimeric protein may play a role in the regulation of mitochondrial membrane cholesterol levels, a prerequisite for the optimal activity of inner mitochondrial membrane-associated enzyme complexes. In addition, it appears that this protein is largely responsible for the differences in membrane cholesterol levels observed in normal and hepatoma mitochondria, a discrepancy which may help to explain the lack of energy production via oxidative phosphorylation in malignant tumor mitochondria.

Chronic psychosocial stress impairs learning and memory and increases sensitivity to yohimbine in adult rats

BACKGROUND

It is well known that intense and prolonged stress can produce cognitive impairments and hippocampal damage and increase noradrenergic activity in humans. This study investigated the hypothesis that chronic psychosocial stress would affect behavior, drug sensitivity, and hippocampal-dependent learning and memory in rats. The work provides a novel connection between animal and human studies by evaluating the effects of stress on a rat's response to yohimbine, an alpha(2) adrenergic receptor antagonist.

METHODS

Rats were exposed to a cat for 5 weeks and randomly housed with a different group of cohorts each day (psychosocial stress). The effects of the stress manipulations were then assessed on open field behavior, spatial learning and memory in the radial arm water maze and the behavioral response to a low dose of yohimbine (1.5 mg/kg).

RESULTS

Stressed rats displayed impaired habituation to a novel environment, heightened anxiety, and increased sensitivity to yohimbine. In addition, the stressed rats exhibited impaired learning and memory.

CONCLUSIONS

There are commonalities between the current findings on stressed rats and from studies on traumatized people. Thus, psychosocial stress manipulations in rats may yield insight into the basis of cognitive and neuroendocrine disturbances that commonly occur in people with anxiety disorders.

Haemostasis in ischaemic stroke and vascular dementia

Abnormalities of coagulation and fibrinolysis may play an important role in the pathogenesis of ischaemic stroke and vascular dementia. We aimed to determine whether haemostatic function is altered in acute recent-onset or chronic ischaemic cerebrovascular disease. We studied consecutive patients with ischaemic stroke (n = 74) and vascular dementia (n = 42) compared with healthy controls (n = 40) in a case-control study. The ischaemic stroke group was assessed twice, 3-10 days after the acute stroke and at 1-3 months. Fibrinogen, fibrin D-dimer (marker of fibrin turnover) and von Willebrand factor (vWF) (marker of endothelial disturbance) were elevated acutely (P < 0.0001) and in the convalescent phase after ischaemic stroke (P < 0.0001, P < 0.0001, and P < 0.01 respectively, compared with controls). Similar results were seen in the vascular dementia group. Stepwise multivariate regression analyses showed that cerebrovascular disease correlated independently with fibrinogen (P < 0.001) and fibrin D-dimer levels (P < 0.001), while vWF correlated independently with electrocardiograph evidence of ischaemic heart disease (P = 0.004). Changes between acute and convalescent phases in ischaemic stroke were slightly inconsistent. However, in the acute stage there were tendencies for fibrinogen, D-dimer and vWF to be increased, and factor VIII was significantly higher. Abnormalities of haemostasis, including increased fibrin turnover and endothelial disturbance, are found in both acute and chronic cerebral ischaemia. Many of these patients have co-existent ischaemic heart disease and this may contribute to some of these changes. Acute ischaemic stroke is associated with transient changes in haemostatic factors; however, most abnormalities persist into the convalescent phase, and are also demonstrable in subjects with vascular dementia.

Proteomic analysis of Fasciola hepatica excretory-secretory products

This paper describes a global investigation of the components of Fasciola hepatica excretory-secretory (ES) products by a proteomic approach. Despite the absence of a F. hepatica genome sequencing project we have shown that it was possible to identify 29 of the 60 prominent proteins found using two-dimensional gel electrophoresis. As well as cathepsin L proteases, a number of enzymes implicated in parasite protection from the host immune system were also found to be present in relatively large abundance. These included superoxide dismutase, thioredoxin peroxidase, glutathione S-transferases and fatty acid binding proteins, all of which may play a part in the detoxification of reactive oxygen intermediates. Interestingly, ovine superoxide dismutase was the only protein from the host identified on the gel. We suggest that the relative abundance and protective nature of the components of the ES products of this organism play an important role in its survival within the host. The precise identification, to individual NCBI database entries, of a number of glutathione S-transferases and cathepsin Ls from F. hepatica, by peptide mass fingerprinting, was hampered by multi-database submissions of the two protein superfamilies from this organism.

A common class of nematode glutathione S-transferase (GST) revealed by the theoretical proteome of the model organism Caenorhabditis elegans

The genome verified C. elegans free-living nematode model is a new tool for investigating gene expression in human and animal nematode parasites. There is limited information on designating glutathione S-transferase (GST) to specific classes in lower invertebrates such as nematodes. Following cloning, amino acid sequence alignment, recombinant expression and Western blotting we provide evidence of a new GST class in nematodes or lower invertebrates.

Tumour dosimetry in human liver following hepatic yttrium-90 microsphere therapy

Radiation dose distributions arising from intrahepatic arterial infusion of 90Y microspheres have been investigated. Tissue samples from normal liver, the tumour periphery and tumour centre were taken from a patient following infusion of 3 GBq of 32 microm diameter resin microspheres labelled with 90Y as treatment for an 80 mm diameter metastatic liver tumour. The measured microsphere distributions in three dimensions were used to calculate radiation dose patterns. Although microspheres concentrated in the tumour periphery, heterogeneous doses were delivered to all tissues. Within the tumour periphery average doses ranged from 200 Gy to 600 Gy with minimum doses between 70 Gy and 190 Gy. The average and minimum doses for the tumour centre sample were 6.8 Gy and 3.7 Gy respectively. In the normal liver sample the average dose was 8.9 Gy with a minimum dose of 5 Gy. Less than 1% of the normal liver tissue volume received more than 30 Gy, the level above which complications have resulted for whole liver exposure using external beam radiotherapy. These calculations suggest that preferential deposition of microspheres in the well-vascularized periphery of large tumours will lead to a high proportion of the tumour volume receiving a therapeutic dose, with most of the normal liver tissue being spared substantial damage.

Inhibition of glutathione S-transferases (GSTs) from parasitic nematodes by extracts from traditional Nigerian medicinal plants

Piliostigma thonningii, Ocimum gratissimum, Nauclea latifolia and Alstonia boonei are used in Nigerian traditional medicines against gastrointestinal helminths of animals and man. Proanthocyanidins were detected in Piliostigma and Nauclea, but not Alstonia or Ocimum. Extracts of these plants killed 50% of brine shrimp nauplii at <10 ppm (Nauclea), 100 ppm (Piliostigma) and <1000 ppm (Ocimum and Alstonia), the Nauclea LD50 being similar to the anthelmintic drug piperazine. Extracts were also toxic to the parasitic nematode Haemonchus infective L3 stage. Nematode glutathione-S-transferases (GSTs) are potential drug targets. Apart from Alstonia all the medicinal plants contained heat-stable inhibitory activities against recombinant Ascaris and Onchocerca GSTs in vitro. Piliostigma, Ocimum and Nauclea had IC50s of 2, 10 and 15 microg/mL respectively for Ascaris GST and 4, 8, 28 microg/mL respectively for Onchocerca GST. We suggest that the inhibitory properties of some of these Nigerian plant extracts against GST may contribute to the pharmacological basis of their efficacy against helminths in traditional herbal use.

Effects of interlayer coupling on the irreversibility lines of NbN/AlN superconducting multilayers

We have studied the temperature dependence of the in-plane resistivity of NbN/AlN multilayer samples with varying insulating layer thickness in magnetic fields up to 7 T parallel and perpendicular to the films. The upper critical field shows a crossover from 2D to 3D behavior in parallel fields. The irreversibility lines have the form (1-T/T(c))(alpha), where alpha varies from 4 / 3 to 2 with increasing anisotropy. The results are consistent with simultaneous melting and decoupling transitions for the low anisotropy sample, and with melting of decoupled pancakes in the superconducting layers for higher anisotropy samples.

Dental self-care among dentate adults: contrasting problem-oriented dental attenders and regular dental attenders

Self-care behaviors are common and can act as substitutes for or supplements to formal health care services. We tested the hypothesis that problem-oriented dental attenders (POAs) report more dental self-care behaviors than do regular dental attenders (RAs), presumably as a substitute for professional care. The Florida Dental Care Study is a longitudinal cohort study of changes in oral health, in which we measured dental self-care behaviors related to three common dental problems: toothache pain, bleeding gums, and tooth loss. Despite using less dental care, POAs were less likely to report "conventional" methods as means to prevent the three dental problems; however, they were more likely to report that homemade remedies, topical medications, or mouthwashes were ways to prevent or treat these problems. POAs were also more likely to believe that "nothing can be done" to prevent these problems. Additionally, POAs had more negative dental attitudes, used less dental care during follow-up, had more dental disease, were the only persons who extracted at least one of their own teeth, and were more likely to use tobacco. With the exception of dental self-extractions, no single self-care belief or behavior distinguished POAs from RAs, nor were POAs likely to have different explanations for dental problems. Instead, the pattern was one of modest differences on a number of items. Although POAs use less dental care, they do not compensate by employing more "conventional" dental self-care behaviors, but report being more likely to employ "unconventional" behaviors. They also are more likely to believe that nothing can be done to prevent dental problems.

Beta-carbonyl substituted glutathione conjugates as inhibitors Of O. volvulus GST2

A series of beta-carbonyl substituted glutathione conjugates were prepared and evaluated as inhibitors of OvGST2. Their specificity for the parasite derived protein was assessed through comparison with their inhibition of human piGST. Inhibition of OvGST2 has been demonstrated at low micromolar concentrations for these conjugates and selectivity for OvGST2 over human pi-GST of greater than 10-fold has been achieved.

Analysis of the distribution of intra-arterial microspheres in human liver following hepatic yttrium-90 microsphere therapy

The microscopic distribution of microspheres in human liver following hepatic infusion of 32 microm diameter resin microspheres labelled with 90Y as treatment for an 80 millimetre diameter liver cancer has been investigated. Microspheres were found to deposit inhomogeneously in tissues, preferentially lodging in a region approximately 6 mm wide around the periphery of the tumour. A relative concentration of microspheres of 50 to 70 times that of normal hepatic parenchyma and 65 to 94 times that in the tumour centre was measured in this region. The deposition of spheres in the tumour periphery was not uniform, and cluster analysis showed that the spheres could be classified into clusters. The number of microspheres in a cluster was skewed towards low numbers and cluster sizes varied from 20 to 1500 microm. The observed deposition patterns indicate that the vascular tumour periphery will receive much greater radiation doses from radioactive microspheres than both normal tissue and the avascular tumour centre.

Xenognosin sensing in virulence: is there a phenol receptor in Agrobacterium tumefaciens?

BACKGROUND

The mechanisms of signal perception and transmission in the 'two-component' autokinase transmitters/response regulators are poorly understood, especially considering the vast number of such systems now known. Virulence induction from the tumor-inducing (Ti) plasmid of Agrobacterium tumefaciens represents one of the best understood systems with regard to the chemistry of the activating signal, and yet the existing data does not support a receptor-mediated perception event for the xenognostic phenols.

RESULTS

Here we provide the first conclusive evidence that a specific receptor must be involved in xenognostic phenol perception, detail structural requirements of the xenognosins necessary for perception by this receptor, and develop a genetic strategy that demonstrates critical components of the phenol recognition system are not encoded on the Ti plasmid.

CONCLUSIONS

Although the basic elements of the two-component system required for phenol-mediated induction of virulence gene expression are encoded on the Ti plasmid, they are dependent on the chromosomal background for even the very first stage of signal perception. This discovery suggests a curious evolutionary history, and also provides functional insight into the mechanisms of two-component signal detection and transmission in general.

Swallowing abnormalities after acute stroke: A case control study

Dysphagia is a common and potentially fatal complication of acute stroke. However, the underlying pathophysiology, especially the relative importance of motor and sensory dysfunction, remains controversial. We conducted a case control study of 23 acute stroke patients (mean age = 72 yr) at a median of 6 days post-stroke and 15 healthy controls (mean age = 76 yr). We used novel methods to assess swallowing in detail, including a timed videoendoscopic swallow study and oral sensory threshold testing using electrical stimulation. Vocal cord mobility and voluntary pharyngeal motor activity were impaired in the stroke group compared with the controls (p = 0.01 and 0.03). There was a delay during swallowing in the time to onset of epliglottic tilt in the stroke group, particularly for semisolids (p = 0.02) and solids (p = 0.01), consistent with a delay in initiation of the swallow. Sensory thresholds were not increased in the stroke group compared with controls. We conclude that pharyngeal motor dysfunction and a delay in swallow initiation are common after acute stroke. Vocal cord mobility is reduced, and this may result in reduced airway protection. We found no evidence to support the hypothesis that oropharyngeal sensory dysfunction is common after acute stroke.

A chimeric prokaryotic ancestry of mitochondria and primitive eukaryotes

We provide data and analysis to support the hypothesis that the ancestor of animal mitochondria (Mt) and many primitive amitochondrial (a-Mt) eukaryotes was a fusion microbe composed of a Clostridium-like eubacterium and a Sulfolobus-like archaebacterium. The analysis is based on several observations: (i) The genome signatures (dinucleotide relative abundance values) of Clostridium and Sulfolobus are compatible (sufficiently similar) and each has significantly more similarity in genome signatures with animal Mt sequences than do all other available prokaryotes. That stable fusions may require compatibility in genome signatures is suggested by the compatibility of plasmids and hosts. (ii) The expanded energy metabolism of the fusion organism was strongly selective for cementing such a fusion. (iii) The molecular apparatus of endospore formation in Clostridium serves as raw material for the development of the nucleus and cytoplasm of the eukaryotic cell.

Effect of loratadine on nitrogen dioxide-induced changes in electrical resistance and release of inflammatory mediators from cultured human bronchial epithelial cells

BACKGROUND

Recent studies have demonstrated that some antihistamines can attenuate histamine-induced release of inflammatory mediators from bronchial epithelial cells.

OBJECTIVE

The purpose of study was to test the hypothesis that loratadine may influence pollution-induced inflammation of the airways by modulating epithelial membrane integrity and the synthesis and/or release of inflammatory mediators from airway epithelial cells.

METHODS

We have cultured human bronchial epithelial cell (HBEC) cultures from surgical explants and investigated the effect of loratadine on NO2-induced changes in both electrical resistance of HBEC cultures and release of IL-8, RANTES, and soluble intercellular adhesion molecule-1 (sICAM-1) from these cells after exposure for 6 hours to either air or 400 ppb NO2.

RESULTS

Exposure for 6 hours to NO2 significantly decreased the electrical resistance of HBEC cultures by 18.1% from baseline (P <.05). Incubation with 0.25 to 25 micromol/L loratadine did not alter the NO2-induced decrease in the electrical resistance of HBEC cultures. NO2 also significantly increased the release of IL-8 from a control value of 52.5 pg/microgram cellular protein to 81.9 pg/microgram cellular protein (P <.05), RANTES from a control value of 0.023 pg/microgram cellular protein to 0.062 pg/microgram cellular protein (P <.05), and sICAM-1 from a control value of 7.7 pg/microgram cellular protein to 16.3 pg/microgram cellular protein (P <.05). The NO2-induced release of all 3 mediators was significantly attenuated by incubation of HBECs with 25 micromol/L loratadine. Incubation with 2.5 micromol/L loratadine also significantly attenuated the NO2-induced release of RANTES and sICAM-1, but not IL-8.

CONCLUSIONS

These results suggest that loratadine has the potential to reduce airway inflammation by modulating the release of inflammatory cytokines from airway epithelial cells.

MOT1 can activate basal transcription in vitro by regulating the distribution of TATA binding protein between promoter and nonpromoter sites

MOT1 is an ATPase which can dissociate TATA binding protein (TBP)-DNA complexes in a reaction requiring ATP hydrolysis. Consistent with this observation, MOT1 can repress basal transcription in vitro. Paradoxically, however, some genes, such as HIS4, appear to require MOT1 as an activator of transcription in vivo. To further investigate the function of MOT1 in basal transcription, we performed in vitro transcription reactions using yeast nuclear extracts depleted of MOT1. Quantitation of MOT1 revealed that it is an abundant protein, with nuclear extracts from wild-type cells containing a molar excess of MOT1 over TBP. Surprisingly, MOT1 can weakly activate basal transcription in vitro. This activation by MOT1 is detectable with amounts of MOT1 that are approximately stoichiometric to TBP. With amounts of MOT1 similar to those present in wild-type nuclear extracts, MOT1 behaves as a weak repressor of basal transcription. These results suggest that MOT1 might activate transcription via an indirect mechanism in which limiting TBP can be liberated from nonpromoter sites for use at promoters. In support of this idea, excess nonpromoter DNA sequesters TBP and represses transcription, but this effect can be reversed by addition of MOT1. These results help to reconcile previous in vitro and in vivo results and expand the repertoire of transcriptional control strategies to include factor-assisted redistribution of TBP between promoter and nonpromoter sites.