Investigation of Drug ResistantAcinetobacter baumannii Virulence Factors Implicated in Intracellular Survival Within Differentiated THP-1 Cells

Introduction/Objective

Acinetobacter baumannii is a nosocomial opportunistic pathogen that is usually associated with mucosal infections such as pneumonia, urinary tract infections or sepsis and less commonly with more severe illnesses such as meningitis, wound infection, or necrotizing fasciitis. Of late, A. baumanniihas been flagged by the CDC as an urgent threat due to multidrug-resistant properties it has acquired, making it a major concern to public health. Due to a sparsity of information on the virulence factors of immune evasion, it has been difficult to understand how this bacterium is able to gain a foothold and cause severe infections. We sought to study how necrotizing fasciitis-associated strains of A. baumannii interact with human macrophages to assess their capabilities in evasion of the host immune response.

Methods/Case Report

To this end, extensively drug resistant A. baumannii was isolated at two timepoints (strains NFAb-1 and NFAb-2) from a patient over the course of a lethal necrotizing fasciitis infection that led to sepsis. The intracellular survival of these two strains was compared with each other, as well as to the type strains, ATCC 19606 and ATCC 17978, within a human macrophage-differentiated monocyte cell line, THP-1. Survival studies were complemented with quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) to investigate expression of potential bacterial virulence factors, Catalase E (KatE), Phospholipase C (PLC), Outer membrane protein A (ompA), and Pilus A (PilA), that could contribute to immune evasion.

Results (if a Case Study enter NA)

The intracellular survival assay demonstrated enhanced survival and bacterial growth of NFAb-1 and NFAb-2 within macrophages compared to ATCC 19606 and 17978. Examining gene expression, KatE, PLC, and OmpA didn’t show any significant differences between the bacterial strains, while the PilA gene had much higher expression in NFAb-1 and NFAb-2 compared to ATCC 19606 and 17978.

Conclusion

This data establishes these nectrotizing fasciitis-causing A. baumannii strains are more likely to sruvivie a macrophage-mediatied immune response and expression of pilus-assocated genes may play a role in these interactions. our studies demonstrate a need to further investigate A. baumannii mechanisms of virulence to understand its ability to evade the immune response in hopes of understanding and combating infections.

123 LEVELS OF PHYSICAL PERFORMANCE AND PHYSICAL ACTIVITY IN OLDER ATTENDEES AT A BONE HEALTH CLINIC

Background

Osteoporosis and sarcopenia are two common conditions seen in community-dwelling older adults. Limited information on physical performance and activity exists in older adults at risk of osteo-sarcopenia. The aim of this study was to examine levels of physical performance and physical activity in patients attending a bone health clinic.

Methods

A cross-sectional study was conducted. Community-dwelling older adults attending a bone health clinic in an acute Irish hospital were invited to participate. Primary outcome measures for physical performance and activity were: grip strength, the Short Physical Performance Battery (SPPB), the Timed Up and Go test (TUG) and the International Physical Activity Questionnaire (IPAQ). Secondary outcomes included: Bone Mineral Density T-scores, diagnosis of probable sarcopenia, osteo-sarcopenia, frailty, fractures and falls history.

Results

104 participants took part in the study. Median age was 76 (IQR 12), ranging from 65 to 91 years. Females accounted for the majority (88.5%) of recruited participants. Osteoporosis was present in 63% and osteopenia in 31%. Low physical activity levels were identified in 29%. Probable sarcopenia ranged from 17 to 37%. Osteo-sarcopenia was identified in 9 to 33% depending on four possible definitions. The most common associations with osteo-sarcopenia were frailty (CFS) and low BMI. Using reduced multivariate regression analysis, physical performance (grip strength, SPPB, TUG) and physical activity (IPAQ) were negatively associated with increased age, comorbidities, frailty and falls. Increased age was associated with all four variables analysed. Comorbidities was associated with grip strength (p=0.005), SPPB (p=0.01), TUG (p=0.041). Frailty (CFS) was associated with SPPB (p< .001), TUG (p< .001), and IPAQ (p< .001). Fall(s) history was associated with SPPB (p< .001) and TUG (p=0.028).

Conclusion

A high proportion of participants were classified as having osteoporosis, probable sarcopenia and osteo-sarcopenia. Completing physical performance and activity measures could provide useful information to clinicians about patients and their potential risks/deficits.

134 PREVALENCE OF SARCOPENIA AND ASSOCIATED FACTORS IN OLDER ADULTS ATTENDING A DAY HOSPITAL SERVICE IN IRELAND

Background

Sarcopenia is a muscle disease that is linked to the effects of ageing, chronic diseases, physical inactivity, and poor nutrition. In Ireland, there is a lack of readily available information on sarcopenia in older adults. The aim of this study was to describe the prevalence and associated factors of sarcopenia in community dwelling older adults attending a day hospital service in Ireland, using the European Working Group of Sarcopenia in Older People (EWGSOP) 2019 guidelines.

Methods

An observational cross-sectional study was conducted, where a consecutive series of older adults attending a day hospital service were invited to participate. The measure of primary interest was the diagnosis of sarcopenia using the EWGSOP 2019 guidelines. Muscle strength was assessed using both, handheld grip strength and the Five Times Sit to Stand Test. Muscle mass was assessed using appendicular skeletal mass adjusted for height using raw data from Bio Impedance Analysis. Physical performance was measured using the Short Physical Performance Battery and the Timed Up and Go Test. We also collected other Comprehensive Geriatric Assessment measures including cognition, nutrition, frailty and physical activity.

Results

A total of 134 participants took part in the study. The mean age was 81.7 (SD +/− 7.1). Sixty-one percent (N = 82) were female. The prevalence of sarcopenia ranged from 27–37% depending on the assessment tool used to assess muscle strength. Sarcopenia was associated with older age, frailty, reduced nutritional state, poor physical performance and reduced anthropometric measures, irrespective of how muscle strength was measured. Independently associated factors differed depending on muscle strength test, except for older age.

Conclusion

The prevalence of sarcopenia in the day hospital ranged from 27–37%. The assessment tool used to assess muscle strength influenced both the prevalence and associated factors of sarcopenia, suggesting scope for further research.

Commercial beef farms excelling in terminal and maternal genetic merit generate more gross profit

Validation of beef total merit breeding indexes for improving performance and profitability has previously been undertaken at the individual animal level; however, no herd-level validation of beef genetic merit and profit has been previously investigated. The objective of the present study was to quantify the relationship between herd profitability and both herd-average terminal and maternal genetic merit across 1,311 commercial Irish beef herds. Herd-level physical and financial performance data were available from a financial benchmarking tool used by Irish farmers and their extension advisors. Animal genetic merit data originated from the Irish Cattle Breeding Federation who undertake the national beef and dairy genetic evaluations. Herd-average genetic merit variables included the terminal index of young animals, the maternal index of dams, and the terminal index of service sires. The herds represented three production systems: 1) cow-calf to beef, 2) cow-calf to weanling/yearling, and 3) weanling/yearling to beef. Associations between herd financial performance metrics and herd average genetic merit variables were quantified using a series of linear mixed models with year, production system, herd size, stocking rate, concentrate input, and the two-way interactions between production system and herd size, stocking rate, and concentrate input included as nuisance factors. Herd nested within the county of Ireland (n = 26) was included as a repeated effect. Herds with young cattle excelling in terminal index enjoyed greater gross and net profit per hectare (ha), per livestock unit (LU), and per kg net live-weight output. The change in gross profit per LU per unit change in the terminal index of young animals was €1.41 (SE = 0.23), while the respective regression coefficient for net profit per LU was €1.37 (SE = 0.30); the standard deviation of the terminal index is €37. Herd-average dam maternal index and sire terminal index were both independently positively associated with gross profit per ha and gross profit per LU. Each one unit increase in dam maternal index (standard deviation of €38) was associated with a €1.40 (SE = 0.48) and €0.76 (SE = 0.29) greater gross profit per ha and per LU, respectively. Results from the present study at the herd-level concur with previous validation studies at the individual animal level thus instilling further confidence among stakeholders as to the expected improvement in herd profitability with improving genetic merit.

International validation of the European Organisation for Research and Treatment of Cancer QLQ-BRECON23 quality-of-life questionnaire for women undergoing breast reconstruction

Background

The aim was to carry out phase 4 international field-testing of the European Organisation for Research and Treatment of Cancer (EORTC) breast reconstruction (BRECON) module. The primary objective was finalization of its scale structure. Secondary objectives were evaluation of its reliability, validity, responsiveness, acceptability and interpretability in patients with breast cancer undergoing mastectomy and reconstruction.

Methods

The EORTC module development guidelines were followed. Patients were recruited from 28 centres in seven countries. A prospective cohort completed the QLQ-BRECON15 before mastectomy and the QLQ-BRECON24 at 4–8 months after reconstruction. The cross-sectional cohort completed the QLQ-BRECON24 at 1–5 years after reconstruction, and repeated this 2–8 weeks later (test–retest reliability). All participants completed debriefing questionnaires.

Results

A total of 438 patients were recruited, 234 in the prospective cohort and 204 in the cross-sectional cohort. A total of 414 reconstructions were immediate, with a comparable number of implants (176) and donor-site flaps (166). Control groups comprised patients who underwent two-stage implant procedures (72, 75 per cent) or delayed reconstruction (24, 25 per cent). Psychometric scale validity was supported by moderate to high item-own scale and item-total correlations (over 0·5). Questionnaire validity was confirmed by good scale-to-sample targeting, and computable scale scores exceeding 50 per cent, except nipple cosmesis (over 40 per cent). In known-group comparisons, QLQ-BRECON24 scales and items differentiated between patient groups defined by clinical criteria, such as type and timing of reconstruction, postmastectomy radiotherapy and surgical complications, with moderate effect sizes. Prospectively, sexuality and surgical side-effects scales showed significant responsiveness over time (P < 0·001). Scale reliability was supported by high Cronbach's α coefficients (over 0·7) and test–retest (intraclass correlation more than 0·8). One item (finding a well fitting bra) was excluded based on high floor/ceiling effects, poor test–retest and weak correlations in factor analysis (below 0·3), thus generating the QLQ-BRECON23 questionnaire.

Conclusion

The QLQ-BRECON23 is an internationally validated tool to be used alongside the EORTC QLQ-C30 (cancer) and QLQ-BR23 (breast cancer) questionnaires for evaluating quality of life and satisfaction after breast reconstruction.

Building Recovery Capital: The Role of Faith-Based Communities in the Reintegration of Formerly Incarcerated Drug Offenders

Recovery capital is an important concept in the field of addiction studies. A person’s access to recovery capital can mean the difference between the termination of addiction and successful reintegration or ongoing criminality and drug use. Increasingly, religious institutions are playing a vital role in the provision of social services, including addiction services that provide access to recovery capital. This article begins by exploring the concept of recovery capital and its utility in the successful reintegration of offenders. It then uses a case study to show how one’s religious organization plays an important role in providing the necessary recovery capital for the desistance of drug abuse and for a successful reintegration into the community. Through in-depth interviews with several persistent adult offenders, this article demonstrates that religious organizations may play an important role in providing the recovery capital that so many persistent drug offenders are lacking.

Measurement of the inclusive electron neutrino charged current cross section on carbon with the T2K near detector

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1  GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³⁸ cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³⁸ cm²/nucleon and the GENIE prediction is 1.08×10⁻³⁸ cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

Search for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ in Super-Kamiokande

We present the results of searches for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ using data from a combined 172.8  kt·yr exposure of Super-Kamiokande-I,-II, and-III. We set lower limits on the partial lifetime for each of these modes: τn→ν[over ¯]π0>1.1×10(33) years and τp→ν[over ¯]π+>3.9×10(32) years at a 90% confidence level.

Search for trilepton nucleon decay via p→e+νν and p→μ+νν in the Super-Kamiokande experiment

The trilepton nucleon decay modes p→e+νν and p→μ+νν violate |Δ(B-L)| by two units. Using data from a 273.4 kt yr exposure of Super-Kamiokande a search for these decays yields a fit consistent with no signal. Accordingly, lower limits on the partial lifetimes of τp→e+νν>1.7×10(32) years and τp→μ+νν>2.2×10(32) years at a 90% confidence level are obtained. These limits can constrain Grand Unified Theories which allow for such processes.

Precise measurement of the neutrino mixing parameter θ23 from muon neutrino disappearance in an off-axis beam

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νμ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3)  eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3)  eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

Search for dinucleon decay into kaons in Super-Kamiokande

A search for the dinucleon decay pp → K+ K+ has been performed using 91.6  kton·yr data from Super-Kamiokande-I. This decay provides a sensitive probe of the R-parity-violating parameter λ112''. A boosted decision tree analysis found no signal candidates in the data. The expected background was 0.28±0.19 atmospheric neutrino induced events and the estimated signal detection efficiency was 12.6%±3.2%. A lower limit of 1.7×10(32)  years has been placed on the partial lifetime of the decay O16 → C14K+ K+ at 90% C.L. A corresponding upper limit of 7.8×10(-9) has been placed on the parameter λ112''.

Observation of electron neutrino appearance in a muon neutrino beam

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3)  eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

Anticancer activity of combination targeted therapy using cetuximab plus vemurafenib for refractory BRAF (V600E)-mutant metastatic colorectal carcinoma

Mismatch-repair-deficient colorectal cancers often contain kinase-activating V600E BRAF mutations, but no clinical utility has yet been demonstrated in this setting for monotherapy using oral braf kinase inhibitors such as vemurafenib or dabrafenib. Recent studies have indicated that tumour resistance to braf inhibition is mediated by upregulated epidermal growth factor receptor (egfr) signalling, disruption of which is a routine treatment strategy in KRAS wild-type colorectal cancer. In this report, we describe the clinical course of a heavily pretreated patient who elected to receive off-label dual-targeted braf- and egfr-inhibitory therapy with good tolerance and apparent clinical benefit.

Who are the PDCO?

In January 2007, the Paediatric Regulation entered into force and established the Paediatric Committee (PDCO) within the European Medicines Agency. The goal of the PDCO is to improve the health of the children of Europe by increasing high-quality research for medicinal products and promoting the development and authorization of such medicines at the EU level. A major function of the PDCO is to formulate and authorize Paediatric Investigation Plans and Paediatric Use Marketing Authorisations. The EU's Seventh Framework Programme for Research has facilitated the establishment of consortia whose ultimate goal is to answer important clinical questions involving medicines commonly used "off-label", in children. The benefits of these consortia include enhanced collaboration amongst paediatricians, scientists and small to medium enterprises whose ultimate goal is to obtain an authorization for a new indication or formulation for use in the paediatric population. It will be interesting in a number of years time to measure the success of this very important European initiative.

Measurement of neutrino oscillation parameters from muon neutrino disappearance with an off-axis beam

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

Evidence for the appearance of atmospheric tau neutrinos in super-Kamiokande

Super-Kamiokande atmospheric neutrino data were fit with an unbinned maximum likelihood method to search for the appearance of tau leptons resulting from the interactions of oscillation-generated tau neutrinos in the detector. Relative to the expectation of unity, the tau normalization is found to be 1.42 ± 0.35(stat)(-0.12)(+0.14)(syst) excluding the no-tau-appearance hypothesis, for which the normalization would be zero, at the 3.8σ level. We estimate that 180.1 ± 44.3(stat)(-15.2)(+17.8) (syst) tau leptons were produced in the 22.5 kton fiducial volume of the detector by tau neutrinos during the 2806 day running period. In future analyses, this large sample of selected tau events will allow the study of charged current tau neutrino interaction physics with oscillation produced tau neutrinos.

Search for differences in oscillation parameters for atmospheric neutrinos and antineutrinos at Super-Kamiokande

We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3)  eV2, 1.0) and is consistent with the overall Super-K measurement.

Indication of electron neutrino appearance from an accelerator-produced off-axis muon neutrino beam

The T2K experiment observes indications of ν(μ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3)  eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

Orf: contagious pustular dermatitis

Orf is a common viral infection in sheep. It spreads to humans by direct contact. It is self-limiting, treatment having no beneficial effect. Misdiagnosis by those unfamiliar with its characteristic features is common, and may result in unnecessary treatment with antibiotics or surgery. We present a series of five cases of Orf in children of farmers in the west of Ireland, seen over a 10 year period.

Kikuchi disease in a child

Kikuchi disease, also called histocytic necrotizing lymphadenitis or focal histiocytic lymphadenitis, is a rare, idiopathic and generally self limited cause of lymphadenitis. It was first described in 1972 in Japan. The most common clinical manifestation is cervical lymphadenopathy with or without systemic symptoms & signs. It almost always runs a benign course and resolves in several weeks to months.

A phase I trial of AEG35156 (XIAP antisense) administered as a continuous intravenous infusion in patients with advanced tumors

3059

Background: The X-linked inhibitor of apoptosis (XIAP) is a potent anti-apoptotic protein. AEG35156 is a synthetic 2nd generation antisense oligonucleotide to human XIAP that enhances cancer cell apoptosis preclinically as a single agent and in combination with chemotherapeutics. Methods: The primary objective was to establish the maximum tolerated dose (MTD) of AEG35156 given as a 7-day continuous infusion every 3 weeks. Other objectives were to determine AEG35156 pharmacokinetics, XIAP inhibition in peripheral blood mononuclear cells and in tumour cells where feasible and document anti-tumour activity. Results: Sixteen adult patients have completed at least one 7-day infusion. Two dose-limiting toxicities (DLT) were observed in five patients treated at 160 mg/m2/day: grade 3 thrombocytopenia for more than 7 days and grade 3 ALT and AST elevation. Seven patients have been treated at 125 mg/m2/day with one DLT of grade 3 transaminase elevation. An approximately 50% decrease in XIAP mRNA was seen in peripheral blood leucocytes three days after the start of infusions at 160mg/m2/day. One patient with small lymphocytic non-Hodgkin’s lymphoma had marked but short lived decreases in peripheral lymphoblasts during AEG35156 administration closely associated with XIAP mRNA knockdown. One patient with breast cancer had an unconfirmed partial response. The trial has now been amended to also determine the MTD of a 3-day continuous infusion every 3 weeks. Three patients have been treated with 3-day infusions at 160mg/m2/day every 3 weeks with no significant toxicities observed and patients are currently being accrued at 213mg/m2/day. Conclusions: AEG35156 can be safely delivered by continuous infusion and preliminary evidence of XIAP mRNA knockdown and antitumour activity has been observed.

[Table: see text]

AntiTNF-alpha agents in the treatment of inflammation

Tumour necrosis factor/cachecin (TNF-alpha) and lymphotoxin (LTalpha / TNF-alpha), 2 members of the TNF family of cytokines, have numerous biological functions, such as induction of apoptosis, cytotoxicity, inflammation, immunoregulation, proliferation and antiviral responses. Although TNF-alpha is produced by many cell types, the majority comes from activated macrophages. The related molecule, LT-alpha is produced mainly by activated lymphocytes and shares many of TNF's properties. TNF-alpha is active in both of its molecular forms, a secreted 17 kDa mature form and a transmembrane 26 kDa precursor. It induces activity by stimulating 2 distinct receptor subtypes, TNFR1 (55 kDa) and TNFR2 (75 kDa). The activation of TNFR1 is generally thought to trigger the majority of inflammatory and apoptotic effects, although TNFR2 has recently been shown to play more of a role in signal transduction than was initially thought. TNF-alpha is responsible for the induction of apoptosis in certain cell types, where it plays a pivotal role in the induction of cytotoxicity, killing of neoplastic cells and deletion of autoreactive T-cell clones. This cytokine, and in particular, its overproduction, has been implicated in the pathogenesis of a variety of immunologically mediated inflammatory diseases, including endotoxic shock, inflammatory bowel disease (IBD), multiple sclerosis (MS) and rheumatoid arthritis (RA). Currently, there is an intense effort underway to regulate TNF-alpha production and activity, in order to treat diseases where TNF-alpha is thought to be pathologically indicated. To achieve this goal, the pharmaceutical industry is currently pursuing a 2 pronged strategy: a) testing biological agents such as antibodies against TNF-alpha or soluble TNF-alpha receptor constructs, and b) identifying small molecular inhibitors directed against targets such as phosphodiesterase-IV (PDE-IV) and TNF-alpha converting enzyme (TACE), a subgroup of the matrix metalloproteinases (MMP). The main difficulties in the clinical implementation of the biological agents are: development of immunogenicity, lack of oral availability and the high cost of production. The currently available small molecular compounds exhibit poor bio-availability and low selectivity, resulting in unacceptable side effects and a low therapeutic index. Despite these hurdles, numerous companies are actively pursuing agents that inhibit TNF-alpha.

Genetic inactivation of prohormone convertase (PC1) causes a reduction in cholecystokinin (CCK) levels in the hippocampus, amygdala, pons and medulla in mouse brain that correlates with the degree of colocalization of PC1 and CCK mRNA in these structures

Prohormone convertase (PC1) is found in endocrine cell lines that express cholecystokinin (CCK) mRNA and process pro CCK to biologically active products. Other studies have demonstrated that PC1 may be a one of the enzymes responsible for the endoproteolytic cleavages that occur in pro CCK during its biosynthesis and processing. Prohormone convertase 1 (PC1) has a distribution that is similar to cholecystokinin (CCK) in rat brain. A moderate to high percentage of CCK mRNA-positive neurons express PC1 mRNA. CCK levels were measured in PC1 knockout and control mice to assess the degree to which loss of PC1 changed CCK content. CCK levels were decreased 62% in hippocampus, 53% in amygdala and 57% in pons-medulla in PC1 knockout mice as compared to controls. These results are highly correlated with the colocalization of CCK and PC1. The majority of CCK mRNA-positive neurons in the pyramidal cell layer of the hippocampus express PC1 mRNA and greater than 50% of CCK mRNA-positive neurons in several nuclei of the amygdala also express PC1. These results demonstrate that PC1 is important for CCK processing. PC2 and PC5 are also widely colocalized with CCK. It may be that PC2, PC5 or another non-PC enzyme are able to substitute for PC1 and sustain production of some amidated CCK. Together these enzymes may represent a redundant system to insure the production of CCK.

Efficacy of repifermin (keratinocyte growth factor-2) against abnormalities in gastrointestinal mucosal transport in a murine model of colitis

Human keratinocyte growth factor-2 (KGF-2) is a member of the fibroblast growth factor family that promotes healing of experimental small intestinal ulceration and colitis. The aim of this study was to determine whether repifermin, a truncated form of recombinant human KGF-2, reverses abnormalities in colonic mucosal transport in a murine model of dextran sulfate sodium (DSS)-induced colitis. Male Swiss-Webster mice were given 4% DSS in drinking water for 7 days and then normal drinking water for 3 days. Repifermin (5 mg kg(-1), i.p.) or vehicle was administered daily for 7 days starting on Day 4 of DSS exposure. On Day 10, net ion transport was measured electrophysiologically in colonic mucosal sheets. Repifermin significantly reduced DSS-induced colonic inflammation measured by tissue myeloperoxidase activity. Concurrently, in colonic tissue taken from mice treated with repifermin, there was a normalization of basal potential difference and short circuit current, and an improvement in the secretory responses to stimulation of muscarinic and ganglionic cholinoceptors. In control mice, repifermin did not interact directly with colonic epithelial cells or intramural neurones to induce immediate changes in net electrogenic transport. The results suggest that repifermin therapy may improve the mucosal electrogenic transport that is impaired during colitis.

OLETF (Otsuka Long-Evans Tokushima Fatty) rats that lack the CCK 1 (A) receptor develop less behavioral sensitization to repeated cocaine treatment than wild type LETO (Long Evans Tokushima Otsuka) rats

OLETF (Otsuka Long-Evans Tokushima Fatty) lacking the CCK 1 (A) receptor have similar spontaneous activity and locomotor response (horizontal and vertical activity) in response to a single injection of cocaine as the wild type LETO (Long Evans Tokushima Otsuka) rats. In contrast, the OLETF rats display more stereotypy in response to the first dose of cocaine than the LETO rats. Tested at 7 and 14 days after a one week daily treatment with cocaine, the LETO rats display robust behavioral sensitization to cocaine while the OLETF rats did not. These results support the hypothesis that endogenous CCK released by cocaine treatment and acting at CCK 1 receptors is required for the development and/or expression of this behavior.

In vivo inhibition of Fas ligand-mediated killing by TR6, a Fas ligand decoy receptor

TR6, a member of the tumor necrosis factor (TNF) receptor superfamily, has recently been shown to bind to Fas ligand (FasL) and inhibit FasL-mediated cell killing in vitro. In the current study, we demonstrate that TR6 can block the lethal activity of FasL in multiple in vitro systems, and extend this finding to an in vivo model of hepatitis. The binding of human TR6 to human FasL was verified with BIAcore chip technology. Human primary hepatocytes, HT-29 cells and Jurkat cells were assayed for viability to demonstrate TR6 inhibition of FasL-mediated cytotoxicity in vitro. Human TR6 was also shown to cross-react with membrane-bound mouse FasL, since the in vitro cytotoxic activity of L929 cells transfected with murine FasL was inhibited in the presence of human TR6. In vivo, FasL-induced acute, lethal, fulminant hepatic apoptosis resulting in death within 2 h of intravenous injection into Fas+ mice, but not Fas- MRL/lpr mice. Pretreatment of mice with TR6 blocked FasL-induced mortality, presumably by attenuating FasL-induced hepatic apoptosis. Thus, in both in vitro and in vivo systems, TR6 acts as a functional FasL decoy receptor and may be clinically useful in the treatment of hepatitis and other diseases associated with FasL-mediated tissue injury.

Activation of CB1 cannabinoid receptors in rat hippocampal slices inhibits potassium-evoked cholecystokinin release, a possible mechanism contributing to the spatial memory defects produced by cannabinoids

Cannabinoid use is known to disrupt learning and memory in a number of species. cholecystokinin (CCK) release and CCK receptors have been implicated in spatial memory processes in rodents. Rat hippocampal CCK interneurons express cannabinoid 1 receptors (CB1). The CB1 agonist R(+)WIN 55,212-2 (WIN+), at 1 and 10 micromol, strongly inhibited potassium-evoked CCK release from rat hippocampal slices, while the inactive isomer S(-)WIN,55,212-3 (WIN-) had no effect. CCK release from cerebral cortical slices was not altered by WIN+.