Systematic identification of biomarker-driven drug combinations to overcome resistance.

The ability to understand and predict variable responses to therapeutic agents may improve outcomes in patients with cancer. We hypothesized that the basal gene-transcription state of cancer cell lines, coupled with cell viability profiles of small molecules, might be leveraged to nominate specific mechanisms of intrinsic resistance and to predict drug combinations that overcome resistance. We analyzed 564,424 sensitivity profiles to identify candidate gene-compound pairs, and validated nine such relationships. We determined the mechanism of a novel relationship, in which expression of the serine hydrolase enzymes monoacylglycerol lipase (MGLL) or carboxylesterase 1 (CES1) confers resistance to the histone lysine demethylase inhibitor GSK-J4 by direct enzymatic modification. Insensitive cell lines could be sensitized to GSK-J4 by inhibition or gene knockout. These analytical and mechanistic studies highlight the potential of integrating gene-expression features with small-molecule response to identify patient populations that are likely to benefit from treatment, to nominate rational candidates for combinations and to provide insights into mechanisms of action.

Increased Fecal Bile Acid Excretion in a Significant Subset of Patients with Other Inflammatory Diarrheal Diseases.

BACKGROUND: Increased fecal bile acid excretion (IBAX) occurs in a third of patients with functional diarrhea. AIMS: To assess the prevalence of IBAX in benign inflammatory intestinal and colonic diseases presenting with chronic diarrhea. METHODS: All patients with known inflammatory diseases or resections who underwent 48 h fecal fat and BA testing for chronic diarrhea at a single center were included. Quiescent disease was based on clinical evaluation and serum, endoscopic and imaging studies. IBAX was defined by: > 2337 µmol total BA/48 h; or primary fecal BAs > 10%; or > 4% primary BA plus > 1000 µmol total BA /48 h. Demographics, fecal weight, fecal fat, stool frequency and consistency were collected. Nonparametric statistical analyses were used for group comparisons. RESULTS: Sixty patients had celiac disease (51 quiescent, 9 active), 66 microscopic colitis (MC: 34 collagenous, 32 lymphocytic), 18 ulcerative colitis (UC), and 47 Crohn's disease (CD). Overall, fecal fat, 48 h stool weight, frequency and consistency were not different among subgroups except for inflammatory bowel disease (IBD) based on disease location. Almost 50% patients with celiac disease and MC had IBAX, with a greater proportion with increased primary fecal BA. Among UC patients, rates of IBAX were higher with pancolonic disease. A high proportion of patients with ileal resection or CD affecting ileum or colon had IBAX. IBAX was present even with quiescent inflammation in UC or CD. CONCLUSIONS: A significant subset of patients with MC, quiescent celiac disease and IBD had increased fecal BA excretion, a potential additional therapeutic target for persistent diarrhea.

Comprehensive pharmacological profiling of neurofibromatosis cell lines.

Patients with Neurofibromatosis type 1 (NF1) and Neurofibromatosis type 2 (NF2) are predisposed to tumors of the nervous system. NF1 patients predominantly develop neurofibromas, and Malignant Peripheral Nerve Sheath Tumors (MPNST) while NF2 patients develop schwannomas and meningiomas. Here we quantified the drug sensitivities of NF1 and NF2 tumor cell lines in a high throughput platform. The platform contained a comprehensive collection of inhibitors of MEK, RAF, RAS, farnesyl transferase, PAK and ERK, representative drugs against many other cancer pathways including Wnt, Hedgehog, p53, EGF, HDAC, as well as classical cytotoxic agents recommended for treating MPNST, such as doxorubicin and etoposide. We profiled seven NF1-associated MPNST cell lines (ST88-14, ST88-3, 90-8, sNF02.2, T265, S462TY, SNF96.2), one sporadic MPNST cell line (STS26), one schwannoma from a NF2 patient (HEI193), one NF2-deficient malignant meningioma (KT21-MG-Luc5D), one mouse NF2 schwannoma (SC4) and one sporadic rat schwannoma (RT4-67 or RT4). NF1 cells were primarily distinguished from NF2 cells and the sporadic MPNST cell line by their sensitivity to MEK and ERK inhibitors, and to a smaller extent their sensitivity to BH3 mimetics and farnesyl transferase inhibitors. The platform was highly successful in predicting the effects of clinical trials for Neurofibromas.

Case of coccidioidomycosis in Ireland.

Coccidioidal infection is a well-recognised cause of pulmonary disease in certain parts of the south-western USA, Central and South America; however, it is rarely encountered elsewhere in the world. We describe the case of a previously healthy man presenting to a Dublin hospital with fever, dry cough and chest pain, following a visit to the western USA. Despite treatment with broad-spectrum antimicrobials, the patient developed progressive bilateral pulmonary infiltrates and a large pleural effusion. After extensive investigations including CT, bronchoscopy and pleural fluid analysis, a diagnosis of pulmonary coccidioidomycosis was made. Following the initiation of appropriate antifungal therapy, the patient made a full recovery. This case was of interest due to the rarity of the disease outside its areas of endemicity and the unusual findings associated with its diagnosis.

Synthesis of imprinted beads by aqueous suspension polymerisation for chiral recognition of antihistamines.

A novel non-stabilised aqueous suspension polymerisation methodology for the preparation of spherical molecularly imprinted polymers is described with chlorpheniramine (CP), d-chlorpheniramine (d-CP), brompheniramine (BP) and d-brompheniramine (d-BP) as the templates, respectively. Using this rapid and simple technique, controlled polymer beads in the low micron range with narrow size distributions were generated by photo-polymerisation. The use of agitation speed as a method of controlling bead size distribution was demonstrated. Enantioselective properties of the imprinted beads were examined and the polymers prepared using d-chlorpheniramine and d-brompheniramine were capable of discriminating between the enantiomers of the template. Cross-selectivity studies were performed by batch rebinding with the influence of template size and functional group orientation of analytes on the recognition properties of the imprinted polymers investigated. Physical characteristics of all polymers were studied by nitrogen sorption porosimetry, particle size analysis and scanning electron microscopy (SEM) in order to gain an insight into the role of such properties on retention behaviour.

Prebiotics from marine macroalgae for human and animal health applications.

The marine environment is an untapped source of bioactive compounds. Specifically, marine macroalgae (seaweeds) are rich in polysaccharides that could potentially be exploited as prebiotic functional ingredients for both human and animal health applications. Prebiotics are non-digestible, selectively fermented compounds that stimulate the growth and/or activity of beneficial gut microbiota which, in turn, confer health benefits on the host. This review will introduce the concept and potential applications of prebiotics, followed by an outline of the chemistry of seaweed polysaccharides. Their potential for use as prebiotics for both humans and animals will be highlighted by reviewing data from both in vitro and in vivo studies conducted to date.

Isolation of identical nitrilase genes from multiple bacterial strains and real-time PCR detection of the genes from soils provides evidence of horizontal gene transfer.

Bacterial enzymes capable of nitrile hydrolysis have significant industrial potential. Microbacterium sp. AJ115, Rhodococcus erythropolis AJ270 and AJ300 were isolated from the same location in England and harbour identical nitrile hydratase/amidase gene clusters. Strain AJ270 has been well studied due to its nitrile hydratase and amidase activity. R. erythropolis ITCBP was isolated from Denmark and carries a very similar nitrile hydratase/amidase gene cluster. In this study, an identical nitrilase gene (nit1) was isolated from the four strains, and the nitrilase from strain AJ270 cloned and expressed in Escherichia coli. Analysis of the recombinant nitrilase has shown it to be functional with activity demonstrated towards phenylacetonitrile. A real-time PCR TaqMan assay was developed that allowed nit1 detection directly from soil enrichment cultures without DNA extraction, with nit1 detected in all samples tested. Real-time PCR screening of isolates from these soils resulted in the isolation of nit1 and also very similar nitrilase gene nit2 from a number of Burkholderia sp. The genes nit1 and nit2 have also been detected in many bacteria of different genera but are unstable in these isolates. It is likely that the genes were acquired by horizontal gene transfer and may be wide-spread in the environment.

The role of animal models in evaluating reasonable safety and efficacy for human trials of cell-based interventions for neurologic conditions.

Progress in regenerative medicine seems likely to produce new treatments for neurologic conditions that use human cells as therapeutic agents; at least one trial for such an intervention is already under way. The development of cell-based interventions for neurologic conditions (CBI-NCs) will likely include preclinical studies using animals as models for humans with conditions of interest. This paper explores predictive validity challenges and the proper role for animal models in developing CBI-NCs. In spite of limitations, animal models are and will remain an essential tool for gathering data in advance of first-in-human clinical trials. The goal of this paper is to provide a realistic lens for viewing the role of animal models in the context of CBI-NCs and to provide recommendations for moving forward through this challenging terrain.

Discourses of disease, discourses of disadvantage: a critical analysis of National Pandemic Influenza Preparedness Plans.

Growing recognition of the threat of pandemic influenza to global health has led to increased emphasis on pandemic influenza preparedness planning. Previous analysis of national pandemic preparedness plans has revealed that those plans paid scant attention to the needs and interests of the disadvantaged. This paper investigates those findings via critical discourse analysis of the same plans as well as World Health Organization guidance documents. The analysis reveals that the texts operate within and as parts of an ordered universe of discourse. Among the six discourses which emerge from the analysis the scientific, political, and legal dominate the social, cultural, and ethical. This order of discourse delineates a specific regime of truths within which the lives, needs, and interests of the disadvantaged are masked or neglected. Unless the plans recognize their discursive construction, implementation of the policies and practices they prescribe runs the risk of further disadvantaging those very populations most likely to require protection.

Thermal desorption characterisation of molecularly imprinted polymers. Part II: Use of direct probe GC-MS analysis to study crosslinking effects.

A powerful method utilising direct probe thermal desorption GC-MS is presented for the study of molecularly imprinted polymers (MIPs). A series of 2-aminopyridine (2-apy)-imprinted methacrylic acid-ethyleneglycol dimethacrylate (MAA-EGDMA) copolymers were prepared under identical conditions but with varying amounts of EGDMA (crosslinking monomer). The use of appropriate temperature programmes permitted template removal, and the subsequent assessment of polymer affinity and specificity, all of which were found to be dependent on polymer composition and morphology. The system was sufficiently sensitive to identify a specific response of imprinted polymers over nonimprinted counterparts. Correlations were found to exist between thermal desorption analysis and solution phase binding, which was assessed by UV spectroscopy, where specificity was found to diminish with decreasing EGDMA concentration. This was attributed to the increased number of free carboxyl groups in those polymers containing a lower percentage of EGDMA. Thermal desorption profiles obtained for the analyte were found to be unaffected by the physical and chemical properties of the solvent used for analyte reloading.

Thermal desorption characterisation of molecularly imprinted polymers. Part I: A novel study using direct-probe GC-MS analysis.

A novel thermal desorption technique using a direct-probe device (Chromatoprobe) attached to a gas chromatograph-mass spectrometer is presented for the thermal pretreatment, characterisation and analysis of molecularly imprinted polymers. The technique is demonstrated as effective for the removal of volatile materials, including template and unreacted monomers, from methacrylic acid-ethylene glycol dimethacrylate copolymers imprinted with 2-aminopyridine. Mass spectrometry is a powerful technique for polymer bleed characterisation. Thermal desorption studies on reloaded template and related compounds are reported as a means of assessing polymer morphology, specific binding by imprinted polymers compared with reference non-imprinted polymers and selective binding by an imprinted polymer for its template. Calibration studies on the thermal desorption technique using an internal standard are presented with R(2) > 0.999. The technique provides a novel method for assessment of polymer thermal stability, composition and morphology.

Social justice and disadvantaged groups.

Because an influenza pandemic would create the most serious hardships for those who already face most serious hardships, countries should take special measures to mitigate the effect of a pandemic on existing social inequalities. Unfortunately, there is little evidence that anybody is thinking about that.

Psychiatric and neuropsychiatric adverse events associated with deep brain stimulation: A meta-analysis of ten years' experience.

Deep brain stimulation (DBS) has been approved by the FDA for use in the treatment of Parkinson's disease, essential tremor, and dystonia. Case reports and case series have reported significant psychiatric side effects in some individuals. The goal of this meta-analysis is to characterize the risks and benefits of DBS and to assess its possible use within the psychiatric setting. A search was conducted on PubMed, EBSCO, and PsycInfo in January 2006 that covered the time period 1 Jan 1996-30 Dec 2005. All identified articles were reviewed and those describing adverse events were further examined with a structured instrument. The initial searches yielded 2667 citations; 808 articles met inclusion criteria for the meta-analysis; 98.2% of studies that specifically assessed motor function reported some level of improvement. Most reported side effects were device or procedure related (e.g., infection and lead fracture). The prevalence of depression was 2-4%, mania 0.9-1.7%, emotional changes 0.1-0.2%, and the prevalence of suicidal ideation/suicide attempt was 0.3-0.7%. The completed suicide rate was 0.16-0.32%. In conclusion, DBS is an effective treatment for Parkinson's disease, dystonia, and essential tremor, and case reports suggest that major depression and OCD may also respond to DBS. Reported rates of depression, cognitive impairment, mania, and behavior change are low, but there is a high rate of suicide in patients treated with DBS, particularly with thalamic and GPi stimulation. Because of the high suicide rate, patients should be prescreened for suicide risk prior to DBS surgery. Additionally, patients should be monitored closely for suicidal behavior post-operatively.

Is patients' preferred involvement in health decisions related to outcomes for patients with HIV?

BACKGROUND: Previous studies suggest that patients who are more involved in their medical care have better outcomes. OBJECTIVES: We sought to compare health care processes and outcomes for patients with HIV based on their preferred level of involvement in health decisions. DESIGN: Cross-sectional analysis of audio computer-assisted interviews with patients at an urban HIV clinic. PATIENTS: One thousand and twenty-seven patients awaiting an appointment with their primary care provider. MEASURES: Patients were asked how they preferred to be involved in decisions (doctor makes most or all decisions, doctor and patient share decisions, patient makes all decisions). We also asked patients to rate the quality of communication with their HIV provider, and their self-reported receipt of and adherence to HAART. RESULTS: Overall, 23% patients preferred that their doctor make all or most decisions, 63% preferred to share decisions with their doctor, and 13% preferred to make all final decisions alone. Compared to patients who prefer to share decisions with their HIV provider, patients who prefer that their provider make all/most decisions were significantly less likely to adhere to HAART (OR [odds ratio] 0.57, 95% CI 0.38-0.86) and patients who preferred to make decisions alone were significantly less likely to receive HAART or to have undetectable HIV RNA in unadjusted analyses (OR 0.52, 95% CI 0.31-0.87 for receipt of HAART; OR 0.64, 95% CI 0.44-0.95 for undetectable HIV RNA). After controlling for potentially confounding patient characteristics and differences in patient ratings of communication quality, patients who preferred that their provider make all/most decisions remained significantly less likely to adhere to HAART (OR 0.58, 95% CI 0.38-0.89); however, the associations with receipt of HAART and undetectable HIV RNA were no longer significant (OR 0.60, 95% CI 0.34-1.05 for receipt of HAART; OR 0.80, 95% C.I 0.53-1.20 for undetectable HIV RNA). CONCLUSIONS: Although previous research suggests that more patient involvement in health care decisions is better, this benefit may be reduced when the patient wants to make decisions alone. Future research should explore the extent to which this preference is modifiable so as to improve outcomes.

What does 'respect' mean? Exploring the moral obligation of health professionals to respect patients.

Respect is frequently invoked as an integral aspect of ethics and professionalism in medicine, yet it is often unclear what respect means in this setting. While we recognize that there are many reasonable ways to think about and use the term 'respect', in this paper, we develop a conception of respect that imposes a distinct moral duty on physicians. We are concerned mainly with the idea of respect for persons, or more specifically, respect for patients as persons. We develop an account of respect as recognition of the unconditional value of patients as persons. Such respect involves respecting the autonomy of patients, but we challenge the idea that respect for autonomy is a complete or self-sufficient expression of respect for persons. Furthermore, we suggest that the type of respect that physicians owe to patients is independent of a patient's personal characteristics, and therefore, ought to be accorded equally to all. Finally, the respect that we promote has both a cognitive dimension (believing that patients have value) and a behavioral dimension (acting in accordance with this belief).

Can patient-centered attitudes reduce racial and ethnic disparities in care?

PURPOSE: Patient-centeredness has been advocated to reduce racial/ethnic disparities in health care quality, but no empirical data support such a connection. The authors' purpose was to determine whether students with patient-centered attitudes have better performance and are less likely to demonstrate disparities with African American compared with white standardized patients (SPs). METHOD: Third-year medical students were assessed by SPs at the Clinical Educational Center of the Johns Hopkins University School of Medicine in 2002. One African American and one white actor were trained as SPs for each of four case scenarios; students were randomly assigned to interact with either SP for each case. Before the exam, students were surveyed about their attitudes towards patient-centered medicine. Students with and without patient-centered attitudes were compared with regard to their performance with African American and white SPs. Outcome measures were student exam scores in interpersonal skill, history taking, physical exam, and counseling. RESULTS: All 177 of eligible students participated in all four case scenarios. With white SPs, students with patient-centered attitudes performed similarly to students without patient-centered attitudes in all four areas. However, with African American SPs, students with patient-centered attitudes performed significantly better than students without patient-centered attitudes in interpersonal skills (71.4 versus 69.4, P = .010), history taking (63.8 versus 61.1, P = .003), and counseling (92.1 versus 88.7, P = .002) and not significantly different in physical exam performance (73.6 versus 68.6, P = .311). CONCLUSIONS: Patient-centered attitudes may be more important in improving physician behaviors with African American patients than with white patients and may, therefore, play a role in reducing disparities.

Are physicians' attitudes of respect accurately perceived by patients and associated with more positive communication behaviors?

OBJECTIVE: To explore the domain of physician-reported respect for individual patients by investigating the following questions: How variable is physician-reported respect for patients? What patient characteristics are associated with greater physician-reported respect? Do patients accurately perceive levels of physician respect? Are there specific communication behaviors associated with physician-reported respect for patients? METHODS: We audiotaped 215 patient-physician encounters with 30 different physicians in primary care. After each encounter, the physician rated the level of respect that s/he had for that patient using the following item: "Compared to other patients, I have a great deal of respect for this patient" on a five-point scale between strongly agree and strongly disagree. Patients completed a post-visit questionnaire that included a parallel respect item: "This doctor has a great deal of respect for me." Audiotapes of the patient visits were analyzed using the Roter Interaction Analysis System (RIAS) to characterize communication behaviors. Outcome variables included four physician communication behaviors: information-giving, rapport-building, global affect, and verbal dominance. A linear mixed effects modeling approach that accounts for clustering of patients within physicians was used to compare varying levels of physician-reported respect for patients with physician communication behaviors and patient perceptions of being respected. RESULTS: : Physician-reported respect varied across patients. Physicians strongly agreed that they had a great deal of respect for 73 patients (34%), agreed for 96 patients (45%) and were either neutral or disagreed for 46 patients (21%). Physicians reported higher levels of respect for older patients and for patients they knew well. The level of respect that physicians reported for individual patients was not significantly associated with that patient's gender, race, education, or health status; was not associated with the physician's gender, race, or number of years in practice; and was not associated with race concordance between patient and physician. While 45% of patients overestimated physician respect, 38% reported respect precisely as rated by the physician, and 16% underestimated physician respect (r=0.18, p=0.007). Those who were the least respected by their physician were the least likely to perceive themselves as being highly respected; only 36% of the least respected patients compared to 59% and 61% of the highly and moderately respected patients perceived themselves to be highly respected (p=0.012). Compared with the least-respected patients, physicians were more affectively positive with highly respected patients (p=0.034) and provided more information to highly and moderately respected patients (p=0.018). CONCLUSION: Physicians' ratings of respect vary across patients and are primarily associated with familiarity rather than sociodemographic characteristics. Patients are able to perceive when they are respected by their physicians, although when they are not accurate, they tend to overestimate physician respect. Physicians who are more respectful towards particular patients provide more information and express more positive affect in visits with those patients. PRACTICE IMPLICATIONS: Physician respectful attitudes may be important to target in improving communication with patients.

Systematic cross-selectivity study of the factors influencing template receptor interactions in molecularly imprinted nitrogen heterocycles.

A systematic cross-selectivity study involving a series of structurally related N-methylated and non-methylated substituted pyridines was performed with the aim of evaluating the parameters responsible for template receptor binding in molecularly imprinted polymers. Variation in binding of substrate structure permitted evaluation of the steric restraints of the imprinted cavity. The electrostatic effects, primarily hydrogen-bonding, were investigated through rebinding in chloroform and acetonitrile. All species were non-covalently imprinted in thermoinduced methacrylic acid-ethylene glycol dimethacrylate co-polymers. Evaluation of template properties indicate that a correlation exists between non-specific binding and template basicity for a series of structural isomers. A correlation between non-specific binding and hydrophobicity was also identified for templates increasing in alkyl character. However no overall correlation was observed, as it was speculated that these factors may be competing. All species imprinted, with the exception of 2-dimethylaminopyridine, produced a selective response for the template species. Varying degrees of cross-selectivity were observed for each imprinted polymer. Polymers imprinted with templates of higher basicity demonstrated a greater degree of cross-selectivity relative to those of lower basicity. While overall binding was reduced in acetonitrile relative to chloroform, specificity was increased. This highlights the intrinsic difference in binding sites within imprinted and non-imprinted sites of the polymer. Finally, while the ability of the template species to form a co-operative interaction may be advantageous in producing a selective imprint it is not a prerequisite. For species based on this co-operative interaction the steric environment in the immediate proximity to the binding functionalities are critical to recognition. Steric hindrance of non-functionally active groups can dramatically impair the formation of interactions.