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Background Optimal treatment of buprenorphine precipitated opioid withdrawal (BPOW) is unclear. Full agonist treatment of BPOW is limited by buprenorphine's high-affinity blockade at mu-opioid receptors (μORs). Buprenorphine's partial agonism (low intrinsic efficacy) at μORs can limit the effectiveness of even massive doses once BPOW has begun. Adjunct medications, such as clonidine, are rarely effective in severe BPOW. Ketamine is an N-methyl-D-aspartate receptor antagonist with a potentially ideal pharmacologic profile for treatment of BPOW. Ketamine reduces opioid withdrawal symptoms independently of direct μOR binding, synergistically potentiates the effectiveness of buprenorphine μOR signaling, reverses (resensitizes) fentanyl induced μOR receptor desensitization, and inhibits descending pathways of hyperalgesia and central sensitization. Ketamine's rapid antidepressant effects potentially address depressive symptoms and subjective distress that often accompanies BPOW. Ketamine is inexpensive, safe, and available in emergency departments. To date, neither ketamine as treatment for BPOW nor to support uncomplicated buprenorphine induction has been described. Case description We report a case of an illicit fentanyl-using OUD patient who experienced severe BPOW during an outpatient low-dose cross taper buprenorphine induction (ie, "microdose"). The BPOW was successfully treated in the emergency department with a combination of ketamine (0.6 mg/kg intravenous over 1 hour) combined with high-dose buprenorphine (16 mg sublingual single dose); 3 days later he was administered a month-long dose of extended-release subcutaneous buprenorphine which was repeated monthly (300 mg). At 90 days the patient remained in treatment and reported continuous abstinence from fentanyl use. Conclusions This single case observation raises important questions about the potential therapeutic role of ketamine as a treatment for BPOW. BPOW is an important clinical problem for which there is currently only limited guidance and no universally accepted approach. Prospective study comparing the effectiveness of differing pharmacologic approaches to treat BPOW is urgently needed.

This is a protocol for a Cochrane Review (prognosis). The objectives are as follows: To evaluate the prognostic effect of the recipient's (i) sex and gender separately (ii) gender as an independent predictor of patient‐relevant outcomes at any time period following kidney or SPK transplantation (Table 1) and explore sources of heterogeneity. We aim to evaluate this prognostic effect by (a) clearly defining the relationship between recipient sex/gender and post‐transplantation outcomes, which would involve identifying reasons for variations between sexes and genders, and then (b) quantifying the magnitude of this relationship. INVESTIGATION OF SOURCES OF HETEROGENEITY BETWEEN STUDIES: Sources of heterogeneity may exist between studies that can have an impact on outcomes. We will explore potential sources, which may include patient age, self‐reported ethnicity, country of transplantation, transplant era, living versus deceased donor transplantation, definitions and units used for outcomes, quality of the study, and the indication for kidney transplantation.

Housing status and additional social determinants of health are important data for clinicians and policy makers to design and implement effective interventions for emergency department (ED) patients with unhealthy alcohol use (UAU).We surveyed patients in an urban, safety-net ED from June to August 2018. UAU was assessed by a validated single-item screening question endorsed by the National Institute on Alcohol Abuse and Alcoholism. Housing status was assessed using items validated for housing stability.Seven hundred fifty-eight patients completed the survey (60% response rate), and 296 (39%; 95% confidence interval: 36%-43%) reported UAU. Patients with and without UAU had the same rates of ED visits (median 2, interquartile range: 1-4; P = 0.69) and hospitalizations (median 0, interquartile range: 0-0; P = 0.31) in the 12 months before index visit. Patients with UAU were more likely to lack stable housing compared to patients without UAU (69% vs 59%; P = 0.006). Illicit drug use and prescription drug misuse was more common in patients with UAU compared to those without UAU (29% vs 14%, Plt; 0.001; and 18% vs 10%; Plt; 0.001, respectively). Only 60 (20.3%) of the 296 patients with UAU had a documented diagnosis of UAU in the medical record.UAU is common in the general ED patient population and usually not clinically recognized. Patients with UAU have high rates of homelessness and co-occurring substance use. Future studies should consider strategies to incorporate social determinants of health and harm reduction treatments into ED-based interventions for UAU.

Aim: This systematic review aims to evaluate the effect of the COVID-19 pandemic on access to health care for patients with CKD. Methods MEDLINE and EMBASE databases were searched up to July 2021 (PROSPERO CRD42021230831). Data relevant to access to health care before and during the COVID-19 pandemic were extracted, including outcomes related to access to general nephrology consultations, telehealth, dialysis services and kidney transplantations. Relative and absolute effects were pooled using a random effects model to account for between-study heterogeneity. Risk of bias was assessed using a modified Quality in Prognostic Studies tool. The certainty of the evidence was rated using the GRADE approach. Results Twenty-three studies across five WHO regions were identified. Reductions in transplantation surgeries were observed during the COVID-19 pandemic compared with the pre-COVID-19 era (risk ratio=2.15, 95%CI=1.51-3.06, I2=90%, p

Rationale & Objective Coronavirus disease 2019 (COVID-19) disproportionately affects people with chronic diseases such as chronic kidney disease (CKD). We assessed the incidence and outcomes of COVID-19 in people with CKD. Study Design Systematic review and meta-analysis by searching MEDLINE, EMBASE, and PubMed through February 2021. Setting & Study Populations People with CKD with or without COVID-19. Selection Criteria for Studies Cohort and case-control studies. Data Extraction Incidences of COVID-19, death, respiratory failure, dyspnea, recovery, intensive care admission, hospital admission, need for supplemental oxygen, hospital discharge, sepsis, short-term dialysis, acute kidney injury, and fatigue. Analytical Approach Random-effects meta-analysis and evidence certainty adjudicated using an adapted version of GRADE (Grading of Recommendations Assessment, Development and Evaluation). Results 348 studies (382,407 participants with COVID-19 and CKD; 1,139,979 total participants with CKD) were included. Based on low-certainty evidence, the incidence of COVID-19 was higher in people with CKD treated with dialysis (105 per 10,000 person-weeks; 95% CI, 91-120; 95% prediction interval [PrI], 25-235; 59 studies; 468,233 participants) than in those with CKD not requiring kidney replacement therapy (16 per 10,000 person-weeks; 95% CI, 4-33; 95% PrI, 0-92; 5 studies; 70,683 participants) or in kidney or pancreas/kidney transplant recipients (23 per 10,000 person-weeks; 95% CI, 18-30; 95% PrI, 2-67; 29 studies; 120,281 participants). Based on low-certainty evidence, the incidence of death in people with CKD and COVID-19 was 32 per 1,000 person-weeks (95% CI, 30-35; 95% PrI, 4-81; 229 studies; 70,922 participants), which may be higher than in people with CKD without COVID-19 (incidence rate ratio, 10.26; 95% CI, 6.78-15.53; 95% PrI, 2.62-40.15; 4 studies; 18,347 participants). Limitations Analyses were generally based on low-certainty evidence. Few studies reported outcomes in people with CKD without COVID-19 to calculate the excess risk attributable to COVID-19, and potential confounders were not adjusted for in most studies. Conclusions The incidence of COVID-19 may be higher in people receiving maintenance dialysis than in those with CKD not requiring kidney replacement therapy or those who are kidney or pancreas/kidney transplant recipients. People with CKD and COVID-19 may have a higher incidence of death than people with CKD without COVID-19.

The multitude of treatment options for atopic dermatitis (AD) makes management frustrating for providers and patients. Eczema action plans (EAPs) have been proposed to improve parental and provider management. We developed a single-site randomized controlled trial to evaluate the impact of an EAP on quality of life (QOL), provider knowledge, and comfort with AD management. Providers were randomized into an EAP-use group and a traditional care group. All patients completed validated AD QOL surveys, and those with AD were verbally administered the survey 1 month later. Providers’ perceptions on managing AD were compared in the EAP and usual use groups. Parents in the EAP group demonstrated a significantly increased understanding of AD treatment, and providers in the EAP group had a significantly increased understanding and management of AD. The EAP is a feasible tool that can be integrated into a busy clinic practice with a positive impact on physicians and patients.

Background Surgical excision is currently recommended after pathologic radial scar is found on breast core needle biopsy because surgical upgrade to carcinoma is not uncommon. The goal of our study was to identify the true pathologic upgrade rate for a "pure" radial scar, those without associated proliferative lesion, based on indication for biopsy, biopsy type, and needle size. Study Design The pathology database of Continuum Health Partners was searched for the terms radial scar and radial sclerosing lesion , from January 2007 to December 2015. From review of 1,513 pathology reports, 292 cases of core biopsies without malignancy were identified. Age, indication for biopsy, type of biopsy, and excisional pathology were obtained. Data were then analyzed using SPSS. Results Two hundred nineteen (75%) of the 292 core biopsies showed pure radial scar without associated proliferative lesion, and 161 (74%) of these patients had surgical excision. Only 1 of these patients had disease that was upgraded to ductal carcinoma in situ—a 2-mm focus located 5 mm away from the radial scar biopsy cavity. This patient also had residual calcifications on mammography after the stereotactic biopsy. Six additional malignant upgrades were found in patients who had radial scar associated with atypical ductal hyperplasia (n = 5) or lobular neoplasia (n = 1) on needle biopsy. Conclusions Surgical excision is unnecessary when radial scar is found at percutaneous needle biopsy without an associated proliferative lesion. Surgical excision is still indicated when radial scar is associated with atypical ductal hyperplasia or lobular neoplasia.

Objectives To investigate the affective, social, behavioral, and physiological effects of the companion robot Paro for people with dementia in both a day care center and a home setting. Design A pilot block randomized controlled trial over 12 weeks. Participants were randomized to the intervention (Paro) or control condition (standard care). Setting Two dementia day care centers and participants’ homes in Auckland, New Zealand. Participants Thirty dyads (consisting of a care recipient with dementia and their caregiver) took part in this study. All care recipients attended dementia day care centers at Selwyn Foundation and had a formal diagnosis of dementia. Intervention Thirty-minute unstructured group sessions with Paro at the day care center were run 2 to 3 times a week for 6 weeks. Participants also had Paro at home for 6 weeks. Measurements At the day care centers, observations of the care recipients’ behavior, affect, and social responses were recorded using a time sampling method. Observations of interactions with Paro for participants in the intervention were also recorded. Blood pressure and salivary cortisol were collected from care recipients before and after sessions at day care. In the home setting, level of cognition, depressive symptoms, neuropsychiatric symptoms, behavioral agitation, and blood pressure were measured at baseline, 6 weeks, and 12 weeks. Hair cortisol measures were collected at baseline and at 6 weeks. Results Observations showed that Paro significantly improved facial expressions (affect) and communication with staff (social interaction) at the day care centers. Subanalyses showed that care recipients with less cognitive impairment responded significantly better to Paro. There were no significant differences in care recipient dementia symptoms, nor physiological measures between the intervention and control group. Conclusion Paro shows promise in enhancing affective and social outcomes for certain individuals with dementia in a community context. Larger randomized controlled trials in community settings, with longer time frames, are needed to further specify the contexts and characteristics for which Paro is most beneficial.

The synthesis and biological evaluation of a series of N-alkyl glycine amide analogs as LTA(4)-h inhibitors and the importance of the introduction of a benzoic acid group to the potency and pharmacokinetic parameters of our analogs are described. The lead compound in the series, 4q, has excellent potency and oral bioavailability.

Leukotriene A4 (LTA4) hydrolase catalyzes a rate-limiting final biosynthetic step of leukotriene B4 (LTB4), a potent lipid chemotactic agent and proinflammatory mediator. LTB4 has been implicated in the pathogenesis of various acute and chronic inflammatory diseases, and thus LTA4 hydrolase is regarded as an attractive therapeutic target for anti-inflammation. To facilitate identification and optimization of LTA4 hydrolase inhibitors, a specific and efficient assay to quantify LTB4 is essential. This article describes the development of a novel 384-well homogeneous time-resolved fluorescence assay for LTB4 (LTB4 HTRF assay) and its application to establish an HTRF-based LTA4 hydrolase assay for lead optimization. This LTB4 HTRF assay is based on competitive inhibition and was established by optimizing the reagent concentration, buffer composition, incubation time, and assay miniaturization. The optimized assay is sensitive, selective, and robust, with a Z' factor of 0.89 and a subnanomolar detection limit for LTB4. By coupling this LTB4 HTRF assay to the LTA4 hydrolase reaction, an HTRF-based LTA4 hydrolase assay was established and validated. Using a test set of 16 LTA4 hydrolase inhibitors, a good correlation was found between the IC50 values obtained using LTB4 HTRF with those determined using the LTB enzyme-linked immunoassay (R = 0.84). The HTRF-based LTA4 hydrolase assay was shown to be an efficient and suitable assay for determining compound potency and library screening to guide the development of potent inhibitors of LTA4 hydrolase.

A series of thiophene-containing non-amidine factor Xa inhibitors is described. Simple methyl-substituted thiophene analogs were relatively weak inhibitors. However, introduction of hydrophilic substituents at C-4 or C-5 of the thiophene afforded inhibitors with low nanomolar potency. Optimization of the thiophene substituent at C-4 afforded subnanomolar inhibitors with improved in vitro anticoagulant activity. Incorporating basic amine substituents on the thiophene increased hydrophilicity and improved anticoagulant activity. The pharmacokinetic profile of one inhibitor was evaluated in dogs, and the X-ray crystal structure of this compound bound to factor Xa provides insight into the observed SAR for binding to factor Xa.

Compound 2 was identified by high throughput screening as a novel PAI-1 inhibitor. Systematic optimization of the A, B, and C segments of 2 resulted in the identification of a more potent compound 39 with good oral bioavailability. The synthesis and SAR data are presented in this report.

Benzothiophene-anthranilamide 1 (3-chloro- N -[2-[[(4-fluorophenyl)amino]carbonyl]-4-methylphenyl]benzo[ b ]thiophene-2-carboxamide) was discovered by high throughput screening to be a highly potent and selective non-amidine inhibitor of human factor Xa with a K i of 15±4 nM. Compound 1 is a selective inhibitor of human factor Xa as suggested by the K i (app) determined for nine other human serine proteases and bovine trypsin. The activity of reconstituted human prothrombinase complex was inhibited by compound 1 when assayed in physiological concentrations of the substrate prothrombin. However, 27-fold higher inhibitor concentrations were needed to achieve the same level of inhibition than were required for the inhibition of free factor Xa, due in part to non-specific binding of the inhibitor to phospholipid under the assay conditions. Failure to demonstrate enzymatic cleavage of compound 1 suggests that compound 1 is solely an inhibitor rather than a substrate for factor Xa. The inhibition of factor Xa by compound 1 was reversible upon dilution of the enzyme/inhibitor mixture. Analyses of the inhibition mechanism with Dixon, Cornish–Bowden, and Lineweaver–Burk plots showed that compound 1 is a linear mixed-type inhibitor with 5-fold higher affinity for free factor Xa than the factor Xa/substrate complex. The linear mixed-type inhibition suggests that compound 1 binds to the active site region of factor Xa, but its binding cannot be fully displaced by the substrate S2222 (1:1 mixture of N -benzoyl-Ile-Glu-Gly-Arg- p -nitroanilide and N -benzoyl-Ile-Glu(γ-OMe)-Gly-Arg- p -nitroanilide hydrochloride). Thus, the inhibition mechanism for compound 1 is novel compared to most serine protease inhibitors including amidine-containing factor Xa inhibitors, which rely on binding to the S1 pocket of the enzyme active site. Compound 1 represents an attractive, novel structural template for further development of efficacious, safe, and potentially orally active human factor Xa inhibitors.

A novel series of diaryloxypyridines have been designed as selective nanomolar factor Xa (fXa) inhibitors for use as anticoagulants. In this paper, we describe our efforts to identify an additional interaction and a replacement for the distal amidine group that binds in the S3/S4 pocket of fXa. Introduction of a hydroxyl group para to the proximal amidine group increases the potency vs fXa by 1-2 orders of magnitude, which is the result of a hydrogen bond to Ser195 of the catalytic triad. A methyl imidazoline and a dimethylamide are good alternatives for the second amidine. These substitutions have increased the selectivity vs the related serine proteases trypsin and thrombin. The synthesis, in vitro activity, and hypothetical modes of binding to fXa based on trypsin crystallographic data are outlined.

A novel series of triaryloxypyridines have been designed to inhibit factor Xa, a serine protease strategically located in the coagulation cascade. Inhibitor 5e has a K I against factor Xa of 0.12 nM and is greater than 8000- and 2000-fold selective over two related serine proteases, thrombin and trypsin, respectively. The 4-position of the central pyridine has been identified as a site that tolerates various substitutions without deleterious effects on potency and selectivity. This suggests that the 4-position of the pyridine ring is an ideal site for chemical modifications to identify inhibitors with improved pharmacokinetic characteristics. This investigation has resulted in inhibitor 5d , which has an oral availability of 6% in dogs. The synthesis, in vitro activity, and in vivo profile of this class of inhibitors is outlined.

Objectives This scoping study is the first step of a multiphase, international project aimed at designing a homecare robot that can provide functional support, track physical and psychological well-being, and deliver therapeutic intervention specifically for individuals with mild cognitive impairment. Design Observational requirements gathering study. Participants and settings Semistructured interviews were conducted with 3 participant groups: (1) individuals with memory challenges, mild cognitive impairment (MCI), or mild dementia (patients; n = 9); (2) carers of those with MCI or dementia (carers; n = 8); and (3) those with expertise in MCI or dementia research, clinical care, or management (experts; n = 16). Interviews took place at the university, at dementia care facilities or other workplaces, at participant's homes, or via skype (experts only). Measurements Semistructured interviews were conducted, transcribed, and reviewed. Results Several key themes were identified within the 4 topics of: (1) daily challenges, (2) safety and security, (3) monitoring health and well-being, and (4) therapeutic intervention. Conclusions A homecare robot could provide both practical and therapeutic benefit for the mildly cognitively impaired with 2 broad programs providing routine and reassurance; and tracking health and well-being. The next phase of the project aims to program homecare robots with scenarios developed from these results, integrate components from project partners, and then test the feasibility, utility, and acceptability of the homecare robot.

Inhibitors based on the benzimidazole scaffold showed subnanomolar potency against Factor Xa with 500–1000-fold selectivity against thrombin and 50–100-fold selectivity against trypsin. The 2-substituent on the benzimidazole ring had a strong impact on the FXa inhibitory activity. Crystallography studies suggest that the 2-substituent may have a conformational effect favoring the extended binding conformation.

A series of indole and carbazole based inhibitors of factor Xa (FXa) has been investigated. The most potent compound inhibits FXa with a Ki of 0.2 nM and has 900- and 750-fold selectivity over thrombin and trypsin, respectively.

With the declining cost and continued convergence of computing and communication technologies, and the availability of networked, computer multimedia communication, instruction supported by Web and e-mail interactive technology has been widely adopted by teaching and learning institutions. Adult learning often seems more consistent with the sort of peer learning and exchange that takes place outside formal education and training situations than within them. When more and more adults, who have been away from schooling for a Dong time, need to develop their knowledge or skills, the demands for adult learning increase. Computer multimedia and networking is regarded as an ideal supporting technology to meet the increasing demands for continuing adult education, but may cause a drastic change in the style of adult learning. This technology may or may not suit the learners' characteristics and their prior learning style. Most important, this change provides a more complex learning environment. For example, Pinhey (1998) stated that the Internet made possible a global education curriculum with various nations involved, so that understanding and tolerance of cultural differences is needed to reach a successful learning outcome. Besides more intercultural communication, there also will be more interactions among learners of different age levels during the learning process. These further considerations are prompting researchers to explore the effect of these factors on adult learning outcomes. The Environment of the Case Study This study reports on the experiences of 18 adult learners who were participating in a 12-week credit course. Students learned how to use the computer and the Internet as learning aids. The course used a combination of face-to-face conventional instruction, group work and e-mail interaction. This compound learning style offered an ideal situation to compare learners' preference and the effect on learning between face-to-face and e-mail media. The participants came from various countries, including China, Fiji, Hong Kong, Korea, New Zealand, the Philippines, South Africa, Taiwan and the United States. The mean age of the students was 38 years; the youngest was 24 while the oldest was 55. A total of 80 percent of the students had a personal computer in their home and 50 percent were able to access the Internet from home. One student was very sophisticated in IT (Information Technology) and more than half of them had more than three years of workplace computer experience. Through questionnaires, observations and interviews, we investigated the relationship between learner characteristics and their learning outcome, and the impact of the media used. We examined the learners' expectation of the teacher, the preferences by which these learners communicated with their learning peers, the conformity issue and the impact of the language barrier. Introvert vs. Extrovert Yi and Majima (1993) asserted that distance learning provided a low-anxiety learning environment and a relaxed atmosphere that lowered the learner's affective filter. Similarly, in this study, we found that the e-mail interactive learning style was more suitable for the introverts than face-to-face learning styles, because introverts may feel more comfortable in expressing themselves in e-mail interactive learning. The barriers of being embarrassed or being shy are partially removed. With more confidence, introverts are more comfortable in communicating with the tutors as well as the learning peers through e-mail interactive learning, but there is no evidence that such learning style is more efficient for introverts than for extroverts. In particular, even though the extroverts tend to prefer face-to-face interactive learning, this phenomenon can not be generalised to those learners who have a sophisticated IT background. After so many years working in front of the computer, the latter have become used to working/studying in front of the computer rather than working with co-learners face-to-face. …

Factor Xa is a serine protease which activates thrombin (factor IIa) and plays a key regulatory role in the blood-coagulation cascade. Factor Xa is, therefore, an important target for the design of anti-thrombotics. Both factor Xa and thrombin share sequence and structural homology with trypsin. As part of a factor Xa inhibitor-design program, a number of factor Xa inhibitors were crystallographically studied complexed to bovine trypsin. The structures of one diaryl benzimidazole, one diaryl carbazole and three diaryloxypyridines are described. All five compounds bind to trypsin in an extended conformation, with an amidinoaryl group in the S1 pocket and a second basic/hydrophobic moiety bound in the S4 pocket. These binding modes all bear a resemblance to the reported binding mode of DX-9065a in bovine trypsin and human factor Xa.

An arylamidine linker has been employed for the solid-phase synthesis of N-substituted amidinoaryloxypyridine analogs 2 via nucleophilic substitution on a fluoropydyl template. Two novel N-substituted amidinoaryloxypyridine derivatives 2a and 2b were discovered via this approach.

A matrix-based compound pooling and deconvolution method has been developed that significantly increased the efficiency of a high-capacity screening program. This method is based on screening pools of 10 compounds. The matrix used to assemble the pools resulted in each compound being assayed twice—each time with a completely different set of pooled compounds. The active compound in an active pool was accurately predicted by determining which compound was present in an active pool both times that a pool containing that compound was tested. This has eliminated the need to re-assay each individual member of active pools. This approach has been tested with a set of 6,680 compounds in three different assays: inhibition of Factor Xa, inhibition of gastrin-releasing peptide receptor binding, and inhibition of nitric oxide synthase (isoform II). Thus significant time is saved not only by pooling the compounds for the initial assay but also by avoiding the need to re-assay all compounds in active pools. Moreover, no false negatives occurred in these assays—an important consideration from a drug discovery perspective. © 1996 Wiley-Liss, Inc.

We report in this communication a simple, facile surface modification strategy to transfer hydrophobic manganese oxide nanoparticles (MONPs) into water by using polyaspartic acid (PASP). We systematically investigated the effect of the size of PASP-MONPs on MRI of normal liver and found that the particles with a core size of 10 nm exhibited greater enhancement than those with larger core sizes.

A non-viral gene delivery nanovehicle based on Alkyl-PEI2k capped MnO nanoclusters was synthesized via a simple, facile method and used for efficient siRNA delivery and magnetic resonance imaging.

An increasing number of studies have demonstrated the positive role nanotopographies can have toward promoting various cell functions. However, the relevant mechanism(s) behind this improvement in biological interactions at the cell–material interface is not well understood. For this reason, here, osteoblast (bone forming cell) functions (including adhesion, proliferation, and differentiation) on two carefully-fabricated diamond films with dramatically-different topographies were tested and modeled. The results over all the time periods tested revealed greater cell responses on nanocrystalline diamond (NCD, grain sizes

The synthesis of amidinoaryloxy 9-benzyl-8-methyl-9H-purine, 7,8-dihydropteridine-6(5H)-one and 5,7-dihydropyrimido[4,5-b][1,4]oxazine-6-one inhibitors of Factor Xa is described. These compounds show nanomolar potency against FXa and maintain high selectivity over thrombin and trypsin.

Recent research has found that cell spreading on materials affects cell functions, including proliferation and differentiation. Also, cell spreading is related to filopodia extension which has been shown to be dependent on substrate topography. To better understand this correlation, live-cell imaging was used here to investigate osteoblast (bone forming cell) filopodia extension and cell spreading on two different kinds of diamond. Nanocrystalline diamond (NCD) and submicron crystalline diamond (SMCD) were fabricated to possess similar surface chemistry but different topographies, consisting of nanoscale spherical grains in NCD and submicron polyhedral grains in SMCD. The filopodia extension and cell expansion results showed that cells on nanoscale topographies had faster filopodia extension and greater expansion area than on submicron topographies. Results indicated that substrate topography has an impact on cell filopodia extension and cell spreading, and NCD promoted filopodia extension and cell expansion better than SMCD.

Leukotriene B-4 (LTB4) is a potent pro-inflammatory mediator that has been implicated in the pathogenesis of multiple diseases, including psoriasis, inflammatory bowel disease, multiple sclerosis and asthma. As a method to decrease the level of LTB4 and possibly identify novel treatments, inhibitors of the LTB4 biosynthetic enzyme, leukotriene A(4) hydrolase (LTA(4)-h), have been explored. Here we describe the discovery of a potent inhibitor of LTA(4)-h, arylamide of glutamic acid 4f, starting from the corresponding glycinamide 2. Analogs of 4f are then described, focusing on compounds that are both active and stable in whole blood. This effort culminated in the identification of amino alcohol 12a and amino ester 6b which meet these criteria. (Less)

There remains a high unmet medical need for a safe oral therapy for thrombotic disorders. The serine protease factor Xa (fXa), with its central role in the coagulation cascade, is among the more promising targets for anticoagulant therapy and has been the subject of intensive drug discovery efforts. Investigation of a hit from high-throughput screening identified a series of thiophene-substituted anthranilamides as potent nonamidine fXa inhibitors. Lead optimization by incorporation of hydrophilic groups led to the discovery of compounds with picomolar inhibitory potency and micromolar in vitro anticoagulant activity. Based on their high potency, selectivity, oral pharmacokinetics, and efficacy in a rat venous stasis model of thrombosis, compounds ZK 814048 (10b), ZK 810388 (13a), and ZK 813039 (17m) were advanced into development.

Reductive amination followed by acylation of polymer-linked formyl aryl amidines generate combinatorial libraries of aryl amidines 8-13. Potent small molecule naphthylamidine inhibitors 12 (Ki

Plasminogen activator inhibitor-1 (PAI-1) is a key negative regulator of the fibrinolytic system. In animal studies, inhibition of PAI-1 activity prevents arterial and venous thrombosis, indicating that PAI-1 inhibitors may be used as a new class of antithrombotics. In this study, we characterize a small molecule PAI-1 inhibitor, ZK4044, which was identified by high throughput screening and chemically optimized. In a chromogenic substrate-based urokinse (uPA)/PAI-1 assay and a tissue-type plasminogen activator (tPA)-mediated clot lysis assay, ZK4044 inhibited human PAI-1 activity with IC50 values of 644+/-255 and 100+/-90 nM, respectively. ZK4044 had no detectable inhibitory activity toward other serpins such as antithrombin III, alpha1-antitrypsin and alpha2-antiplasmin, indicating that ZK4044 is a specific PAI-1 inhibitor. ZK4044 was shown to bind directly to PAI-1 and prevent the binding of PAI-1 to tPA in a dose-dependent manner in surface plasmon resonance Biacore-based experiments. ZK4044 also prevented PAI-1/tPA complex formation, as analyzed by SDS/PAGE. ZK4044 had little effect on elastase-mediated cleavage of active PAI-1, indicating that the primary mode of action of ZK4044 is most likely to directly block the PAI-1/tPA interaction rather than to convert active PAI-1 to latent PAI-1. In the chromogenic substrate-based uPA/PAI-1 assay, ZK4044 was approximately 2-fold less potent against a mutant PAI-1 (14B-1), which contains four mutations at N150H, K154T, Q319L and M354I, compared with wild-type PAI-1, suggesting that the ZK4044 binding site on the surface of PAI-1 is close to these mutant residues. Together, our data show that ZK4044 represents a new class of small molecule PAI-1 inhibitors with anti-thrombotic potential.

Compound 2 was identified by high throughput screening as a novel PAI-1 inhibitor. Systematic optimization of the A, B, and C segments of 2 resulted in the identification of a more potent compound 39 with good oral bioavailability. The synthesis and SAR data are presented in this report.

Compound 1 was identified by high throughput screening as a novel, potent, non-amidine factor Xa inhibitor with good selectivity against thrombin and trypsin. A series of modifications of the three aromatic groups of 1 was investigated. Substitution of chlorine or bromine for fluorine on the aniline ring led to the discovery of subnanomolar factor Xa inhibitors. Positions on the anthranilic acid ring that can accommodate further substitution were also identified.

A novel potent and selective aminophenol scaffold for fXa inhibitors was developed from a previously reported benzimidazole-based naphthylamidine template. The aminophenol template is more synthetically accessible than the benzimidazole template, which simplified the introduction of carboxylic acid groups. Substitution of a propenyl-para-hydroxy-benzamidine group on the aminophenol template produced selective, sub-nanomolar fXa inhibitors. The potency of the inhibitors is partially explained with the aid of a trypsin complex crystal structure.

A novel series of triaryloxypyridines have been designed to inhibit factor Xa, a serine protease strategically located in the coagulation cascade. Inhibitor 5e has a K(I) against factor Xa of 0.12nM and is greater than 8000- and 2000-fold selective over two related serine proteases, thrombin and trypsin, respectively. The 4-position of the central pyridine has been identified as a site that tolerates various substitutions without deleterious effects on potency and selectivity. This suggests that the 4-position of the pyridine ring is an ideal site for chemical modifications to identify inhibitors with improved pharmacokinetic characteristics. This investigation has resulted in inhibitor 5d, which has an oral availability of 6% in dogs. The synthesis, in vitro activity, and in vivo profile of this class of inhibitors is outlined.

Factor Xa (FXa) is a trypsin-like serine protease that plays a key role in blood coagulation linking the intrinsic and extrinsic pathways to the final common pathway of the coagulation cascade. During our initial studies, we observed facile photochemical conversion of the known FXa/tPA inhibitor, BABCH ?(E,E)-2, 7-bis(4-amidinobenzylidene)cycloheptan-1-one, 1a, to the corresponding (Z,Z) olefin isomer, 1c (FXa K(i) = 0.66 nM), which was over 25,000 times more potent than the corresponding (E,E) isomer (1a, FXa K(i) = 17 000 nM). In order to determine the scope of this observation, we expanded on our initial investigation through the preparation of the olefin isomers in a homologous series of cycloalkanone rings, 4-substituted cyclohexanone analogues, and modified amidine derivatives. In most cases the order of potency of the olefin isomers was (Z,Z) > (E,Z) > (E,E) with the cycloheptanone analogue (1c) showing the most potent factor Xa inhibitory activity. In addition, we found that selectivity versus thrombin (FIIa) can be dramatically improved by the addition of a carboxylic acid group to the cycloalkanone ring as seen with 8c (FXa K(i) = 6.9 nM, FIIa K(i) > 50,000 nM). Compounds with one or both of the amidine groups substituted with N-alkyl substituents or replaced with amide groups led to a significant loss of activity. In this report we have demonstrated the importance of the two amidine groups, the cycloheptanone ring, and the (Z,Z) olefin configuration for maximum inhibition of FXa within the BABCH template. The results from this study provided the foundation for the discovery of potent, selective, and orally active FXa inhibitors.

A novel series of 2,6-diphenoxypyridines has been designed to inhibit factor Xa, a serine protease strategically located in the coagulation cascade. The evolution from the photochemically unstable bisamidine (Z,Z)-BABCH to potent bisamidine compounds with a pyridine heterocycle as the core scaffold has been achieved. The most potent compound in the series, 6h, has a Ki for human factor Xa of 12 nM. The selectivity of 6h against bovine trypsin and human thrombin was greater than 90- and 1000-fold, respectively. Two proposed modes of binding of 6h to factor Xa are made based on the crystal structures of 6h by itself and of 6h bound to bovine trypsin.

The synthesis of amidinoaryloxy 9-benzyl-8-methyl-9H-purine, 7,8-dihydropteridine-6(5H)-one and 5,7-dihydropyrimido[4,5-b][1,4]oxazine-6-one inhibitors of Factor Xa is described. These compounds show nanomolar potency against FXa and maintain high selectivity over thrombin and trypsin.

Exploring the cell-material interface is an emerging area of great interest in biomaterial science. Specifically, creating nanostructured surface interfaces to improve biomaterial efficacy is one of these key focus topics. As an example, an increasing number of studies have demonstrated the positive role nanostructured surfaces can have towards promoting various cell functions. However, the relevant mechanism behind this improvement in biological interactions at the cell-implant interface is not well understood. For this reason, here, osteoblast (bone forming cells) and fibroblast (fibrous, soft tissue forming cells) functions (including adhesion and proliferation) on two carefully fabricated diamond films with dramatically different topographies were tested. The results revealed greater cell responses on nanocrystalline diamond (grain sizes