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1.
Am Soc Clin Oncol Educ Book ; 44(3): e438658, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38875505

ABSTRACT

The management of renal cell carcinoma (RCC) has advanced significantly in the past two decades. Many promising functional imaging modalities such as radiolabeled tracer targeting carbonic anhydrase IX and prostate-specific membrane antigen are under development to detect primary kidney tumors, stage systemic disease, and assess treatment response in RCC. Immune checkpoint inhibitors targeting PD-1 and cytotoxic T-cell lymphocyte-4 have changed the treatment paradigm in advanced RCC. Trials investigating novel mechanisms such as LAG-3 immune checkpoint inhibition, chimeric antigen receptor T-cell therapies, and T-cell engagers targeting RCC-associated antigens are currently ongoing. With the rapidly changing treatment landscape of RCC, the treatment sequence strategies will continue to evolve. Familiarity with the toxicities associated with the therapeutic agents and how to manage them are essential to achieve optimal patient outcomes. This review summarizes the recent developments of functional imaging and immunotherapy strategies in RCC, and the evidence supports treatment sequencing.


Subject(s)
Carcinoma, Renal Cell , Immunotherapy , Kidney Neoplasms , Humans , Carcinoma, Renal Cell/therapy , Immunotherapy/methods , Kidney Neoplasms/therapy , Immune Checkpoint Inhibitors/therapeutic use
2.
Mol Cancer Res ; 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38912907

ABSTRACT

Wnt-signaling pathway (WSP) alterations have been identified in patients with prostate cancer (PCa) and are implicated in disease progression and hormonal resistance. We utilized a multi-institutional dataset to characterize molecular alterations in the canonical and non-canonical WSP in PCa. Patients with PCa who underwent tissue-based genomic sequencing were investigated. Tumors with somatic activating mutations in CTNNB1 or RSPO2, or inactivating mutations in either APC or RNF43 were characterized as having aberrant canonical Wnt signaling (WSP-activated). Overall survival (OS) analyses were restricted to microsatellite stable (MSS) tumors lacking RNF43 G659fs* mutations. We also investigated non-canonical WSP by evaluation of ROR1, ROR2, and WNT5 in WSP-activated versus WSP wild-type (WSP-WT) tumors. Of 4,138 PCa samples, 3,684 were MSS. Among MSS tumors, 42.4% were from metastatic sites, of which 19.1% were WSP-activated, and 57.6% from the prostate, of which 10.1% were WSP-activated. WSP-activated tumors were more prevalent in metastatic sites than in primary PCa. WSP-activated PCa exhibited more SPOP mutations and higher expression of canonical WSP activators than WSP-WT tumors. ROR1 gene expression was elevated in WSP-activated tumors from both primary and metastatic sites. M2 macrophages predominated the tumor microenvironment in WSP-activated tumors. There was no significant difference in OS between WSP-activated and WSP-WT PCa patients. WSP-activated PCa demonstrated a more immunosuppressed tumor microenvironment and a pronounced upregulation of ROR1 gene expression, underscoring its potential involvement in the crosstalk between canonical and non-canonical Wnt signaling pathways. Implications: Our findings may provide rationale for developing novel therapeutic strategies targeting Wnt-activated PCa.

3.
Health Soc Work ; 49(2): 87-94, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38478764

ABSTRACT

Homelessness is a complex public health problem in the United States. Current or ongoing history of trauma among individuals adds to the complexity and challenges of homelessness. Our study assessed the moderating role of self-harm in the association between emergency department (ED) service utilization and trauma-induced homelessness (TIH) among adults in Texas. Homeless adults (N = 282) who completed their baseline Vulnerability Index Service Prioritization Decision Assistance Prescreen Tool survey between February 2021 and February 2022 at a Local Mental Health Authority in Texas were selected. The outcome variable, TIH, was assessed by current period of homelessness due to experiencing trauma or abuse. The main independent variable was ED utilization, while self-harm in the past year was assessed as the moderating variable. A multivariate logistic regression with a moderation analysis was conducted while adjusting for the covariates. Individuals who utilized ED services and engaged in self-harm and risky behaviors had greater odds of experiencing current period of TIH. Male respondents were less likely to experience TIH. Finally, engaging in self-harm significantly moderated the association between ED service use and TIH. This study may help inform efforts to develop tailored interventions and promote resilience-based approaches to improve health outcomes among individuals experiencing homelessness due to TIH.


Subject(s)
Emergency Service, Hospital , Ill-Housed Persons , Self-Injurious Behavior , Humans , Ill-Housed Persons/psychology , Ill-Housed Persons/statistics & numerical data , Male , Texas/epidemiology , Female , Emergency Service, Hospital/statistics & numerical data , Self-Injurious Behavior/epidemiology , Self-Injurious Behavior/psychology , Adult , Middle Aged , Surveys and Questionnaires , Patient Acceptance of Health Care/statistics & numerical data , Wounds and Injuries/psychology , Wounds and Injuries/epidemiology
4.
Urogynecology (Phila) ; 30(6): 557-563, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38118059

ABSTRACT

IMPORTANCE: Millions of people rely on social media platforms, including TikTok, for health-related information. TikTok has not yet been evaluated as an information source for overactive bladder (OAB) third-line therapies. OBJECTIVES: Our aim was to assess TikTok videos on third-line therapies for OAB for misinformation and quality. STUDY DESIGN: In this cross-sectional analysis, we abstracted the top 50 TikTok videos for keywords: "Axonics," "sacral neuromodulation," "Interstim," "PTNS," "posterior tibial nerve stimulation," and "bladder Botox." Videos were scored for quality by 3 independent reviewers using the Medical Quality Video Evaluation Tool (MQ-VET). Two reviewers determined if videos contained misinformation. RESULTS: Of 300 videos screened, 119 videos were included. Twenty-four (21%) were created by medical professionals (MPs). Medical professional videos were more frequently shared (5 vs 1, P < 0.01) but had similar views, likes, comments, and length. Although MP videos had significantly higher MQ-VET scores (43 vs 27, P < 0.01), there was no difference in the rate of misinformation between MP and non-MP videos (21% vs 18%). Twenty-two videos (18.4%) contained misinformation, which were 3 times longer (50.5 vs 15 seconds, P < 0.01) and had higher MQ-VET scores (34.5 vs 27, P = 0.03) than those without misinformation. Common themes of misinformation pertained to therapy indication, mechanism of action, and patient limitations after undergoing therapy. CONCLUSIONS: Many TikTok videos on OAB third-line therapies contain misinformation. Most of these videos were not of high quality and created by the public. Medical professionals should be aware of misinformation permeating TikTok, given its large audience, and aim to promote or offer educational material of better accuracy and quality.


Subject(s)
Social Media , Urinary Bladder, Overactive , Video Recording , Urinary Bladder, Overactive/therapy , Humans , Cross-Sectional Studies , Consumer Health Information
5.
Neurourol Urodyn ; 42(4): 837-844, 2023 04.
Article in English | MEDLINE | ID: mdl-36840909

ABSTRACT

PURPOSE: Chronic pelvic pain syndromes (CPPS) are commonly encountered by urologists and urogynecologists and pose diagnostic and therapeutic challenges. Body maps have been helpful adjuncts to verbal descriptions of pain and may serve a role in phenotyping what is known to be a heterogeneous patient population. The aim of this study was to assess whether patterns of pain as marked on a body map of the pelvis exist among common CPPS diagnoses. The secondary aim was to investigate the association between the total number of pain locations marked on the map and clinical indices in patients with 1 to 3 CPPS diagnoses. MATERIALS AND METHODS: Data was collected on patients who visited the Northwell Health Pelvic Pain Treatment Center (PPTC) from January to May 2022 and were diagnosed with at least one of four major CPPS diagnoses: interstitial cystitis/bladder pain syndrome (IC/BPS), pelvic floor myalgia (PFM), chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and vulvodynia. Demographic data as well as survey data from pelvic pain maps, Genitourinary Pain Index (GUPI) forms, and the short form-6 of the Pain Catastrophizing Scale (PCS-6) were recorded. Descriptive statistics among CPPS groups and Pearson correlations among the number of CPPS diagnoses were computed. RESULTS: One hundred seventy females and 125 males with CPPS were included in the study. Significant cross-over in mapping patterns was notable between IC/BPS and PFM groups, both most commonly marking "abdomen" and "genital" regions. The most distinct pattern of pain was seen in patients with CP/CPPS and in patients with vulvodynia. Among the total sample, as the mean number of pain locations marked within the pelvis increased, GUPI and PCS scores increased (p < 0.05). As the number of CPPS diagnoses increased, the strength of the relationship independently increased. CONCLUSIONS: Pelvic body mapping demonstrated that different forms of CPPS displayed different distributions of pain, but mapping was not predictive of any diagnostic group. Nevertheless, the pelvic body map proved useful in identifying precise locations of pain and may help uncover regions of pain that cannot be easily communicated. The total number of pain sites marked appeared to correlate with worse clinical features.


Subject(s)
Chronic Pain , Cystitis, Interstitial , Vulvodynia , Male , Female , Humans , Chronic Disease , Vulvodynia/complications , Chronic Pain/therapy , Pelvic Pain/diagnosis , Cystitis, Interstitial/complications , Pelvis
6.
G3 (Bethesda) ; 11(1)2021 01 18.
Article in English | MEDLINE | ID: mdl-33561251

ABSTRACT

Undergraduate students participating in the UCLA Undergraduate Research Consortium for Functional Genomics (URCFG) have conducted a two-phased screen using RNA interference (RNAi) in combination with fluorescent reporter proteins to identify genes important for hematopoiesis in Drosophila. This screen disrupted the function of approximately 3500 genes and identified 137 candidate genes for which loss of function leads to observable changes in the hematopoietic development. Targeting RNAi to maturing, progenitor, and regulatory cell types identified key subsets that either limit or promote blood cell maturation. Bioinformatic analysis reveals gene enrichment in several previously uncharacterized areas, including RNA processing and export and vesicular trafficking. Lastly, the participation of students in this course-based undergraduate research experience (CURE) correlated with increased learning gains across several areas, as well as increased STEM retention, indicating that authentic, student-driven research in the form of a CURE represents an impactful and enriching pedagogical approach.


Subject(s)
Drosophila , Genomics/education , Universities , Animals , Blood Cells , Drosophila/genetics , Humans , Students
7.
Crit Rev Food Sci Nutr ; 57(5): 1017-1038, 2017 Mar 24.
Article in English | MEDLINE | ID: mdl-26115419

ABSTRACT

N-Acetyl-d-neuraminic acid (NANA), more commonly known by its trivial name sialic acid, is an endogenous human and ubiquitous nutritional monosaccharide. As a bound sugar at the terminal positions of glycans NANA is known to play important roles in many biological events. The data that exist on the occurrence of the free monosaccharide in breast milk and nutrition, however, are less commonly discussed. In most foods of animal origin, sialic acid occurs as a mixture of NANA and N-glycolyl-d-neuraminic acid (NGNA), a hydroxylated derivative of NANA that is not found in humans. The dietary intake of NGNA has been identified as a risk factor for long-term adverse health effects. Therefore, we present summaries on the biochemistry, metabolism, bioavailability, and the data on NANA and NGNA levels that occur in diverse foods. Finally, we discuss the emerging data demonstrating that free NANA is linked to positive nutritional effects including pronounced antioxidative properties. These data and the extremely high safety profile of NANA justify dietary enrichment at levels that correspond to the dietary intake of NANA in infants through breast milk.


Subject(s)
Functional Food/analysis , Milk, Human/chemistry , Monosaccharides/chemistry , N-Acetylneuraminic Acid/chemistry , Animals , Antioxidants/analysis , Brain/physiology , Clinical Trials as Topic , Cognition , Humans , Infant , Infant Formula/chemistry , Models, Animal , Prebiotics/analysis
8.
Regul Toxicol Pharmacol ; 72(1): 39-48, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25728407

ABSTRACT

l-Fucose is a natural monosaccharide present in mammals where it is found predominantly as an O-glycosidically linked component of glycoproteins, glycolipids, and oligosaccharides. It is also present in its free form in human breast milk (human milk monosaccharide). l-Fucose plays important roles in the development of the immune and nervous systems and is involved in cognitive function and memory formation. The human-identical milk monosaccharide l-fucose is therefore proposed for use in infant formulas to better simulate the free saccharides present in human breast milk. As part of the safety evaluation of l-fucose, a subchronic dietary toxicity study preceded by an in utero phase was conducted in Sprague-Dawley rats. l-Fucose was without maternal toxicity or compound-related adverse effects on female reproduction and general growth and development of offspring at a maternal dietary level up to 1%, equivalent to a dose of 1655 mg/kg body weight (bw)/day. During the subchronic phase, no compound-related adverse effects were observed in first generation rats at dietary levels of up to 1% (highest level tested), corresponding to doses of 516 and 665 mg/kg bw/day in males and females, respectively. l-Fucose was non-genotoxic in a series of in vitro genotoxicity/mutagenicity tests. These results support the safe use of l-fucose in infant formula and as a food ingredient at levels equivalent to those present in human breast milk.


Subject(s)
Fucose/administration & dosage , Infant Formula/pharmacology , Milk, Human/metabolism , Monosaccharides/adverse effects , Animals , Female , Humans , Infant , Male , Mutagenicity Tests/methods , Rats , Rats, Sprague-Dawley , Reproduction/drug effects , Safety
9.
Thromb Haemost ; 113(3): 599-604, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25338662

ABSTRACT

Factor Va enhances the rate of prothrombin activation by factor Xa by four to five orders of magnitude. Production of initiating levels of factor Va from its precursor, factor V, is a critical event early in haemostasis, as factor V exhibits negligible cofactor activity. While thrombin is the most potent physiological back-activator of factor V, the first prothrombinase complexes require a source of factor Va prior to thrombin generation. A recent study by Whelihan et al. (J Thromb Haemost 2010; 8:1532-1539) identified factor XIa as a candidate for the initial thrombin-independent activation of factor V, although this reaction was slow and required relatively high concentrations of factors V and XIa. Activated platelets secrete polyphosphate, which we previously showed to be potently procoagulant. We now report that polyphosphate greatly accelerates factor V activation by factor XIa, and that this is supported by polyphosphate polymers of the size secreted by activated human platelets. This finding provides additional evidence that factor XIa-mediated generation of factor Va may contribute to the initiation of haemostasis.


Subject(s)
Blood Platelets/drug effects , Factor V/metabolism , Factor XIa/metabolism , Polyphosphates/pharmacology , Blood Platelets/enzymology , Dose-Response Relationship, Drug , Enzyme Activation , Hemostasis/drug effects , Humans , Kinetics , Molecular Weight , Polyphosphates/blood , Polyphosphates/chemistry , Protein Binding
10.
Expert Rev Cardiovasc Ther ; 12(12): 1419-25, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25370342

ABSTRACT

Atherosclerotic renovascular disease is the most common cause of secondary hypertension. The patients with renovascular disease are at increased risk for adverse cardiac outcomes. Recent trials comparing medical therapy alone to medical therapy with stenting are flawed, but lay to rest any existing debate that unselected revascularization is unwarranted; however, revascularization may be appropriate in high-risk populations. Defining an appropriate population for revascularization is an area of ongoing study. Furthermore, delivery of optimal medical therapy in this population is inadequate. This review describes recent developments in renal artery revascularization.


Subject(s)
Arteriosclerosis/therapy , Hypertension, Renovascular/therapy , Renal Artery Obstruction/therapy , Renal Artery/surgery , Stents , Animals , Humans , Kidney/blood supply
11.
Regul Toxicol Pharmacol ; 70(2): 482-91, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25111575

ABSTRACT

N-Acetyl-d-neuraminic acid (Neu5Ac) is the predominant form of sialic acid (Sia) in humans, while other mammals express Sia as a mixture with N-glycolyl-d-neuraminic acid (Neu5Gc). Neu5Ac occurs in highest levels in the brain and in breast milk, and is therefore, coined a human-specific milk monosaccharide, and is thought to play an important nutritional role in the developing infant. Synthesized human-identical milk monosaccharide (HiMM) Neu5Ac is proposed for use in infant formulas to better simulate the free saccharides present in human breast milk. As part of the safety evaluation of HiMM Neu5Ac, a subchronic dietary toxicity study preceded by an in utero phase was conducted in Sprague-Dawley rats. Neu5Ac was without maternal toxicity or compound-related adverse effects on female reproduction and on the general growth and development of offspring at a maternal dietary level of up to 2%, equivalent to a dose of 1895mg/kg body weight (bw)/day. During the subchronic phase, no compound-related adverse effects were observed in first generation rats at dietary levels of up to 2% (highest level tested), corresponding to doses of 974 and 1246mg/kgbw/day in males and females, respectively. Neu5Ac also was non-genotoxic in a series of in vitro genotoxicity/mutagenicity tests. These results support the safe use of Neu5Ac both in infant formula and as a food ingredient at levels equivalent to those found naturally in human breast milk.


Subject(s)
Infant Formula/metabolism , Milk, Human/metabolism , Monosaccharides/adverse effects , N-Acetylneuraminic Acid/adverse effects , Neuraminic Acids/adverse effects , Animals , Chemical Safety/methods , Female , Humans , Infant , Male , Mutagenicity Tests/methods , Rats , Rats, Sprague-Dawley
12.
Vasc Med ; 19(3): 190-204, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24879715

ABSTRACT

Increasing use of the new oral anticoagulants (NOACs) - dabigatran, rivaroxaban, and apixaban - has prompted considerable discussion in the medical community even as warfarin remains the mainstay of therapy. This article raises 10 controversial issues regarding the use of NOACs for stroke prevention in patients with atrial fibrillation, and offers a review of the latest available evidence. We provide a brief overview of the mechanism and dosing of these drugs, as well as a summary of the key clinical trials that have brought them into the spotlight. Comparative considerations relative to warfarin such as NOAC safety, efficacy, bleeding risk, reversibility, drug-transitioning and use in patients well controlled on warfarin are addressed. Use in select populations such as the elderly, those with coronary disease, renal impairment, or on multiple anti-platelet drugs is also discussed. Finally, we consider such specific issues as comparative efficacy, off-label use, cost, rebound and management during events. Ultimately, the rise of the NOACs to mainstream use will depend on further data and clinical experience amongst the medical community.

13.
Expert Rev Cardiovasc Ther ; 11(10): 1337-47, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24138521

ABSTRACT

This review aims to describe new developments in coronary revascularization strategies for patients with pre-existing Type 2 diabetes mellitus (DM). Recommended strategies for revascularization have been an active area of study with recent important developments. In patients with Type 2 DM and multivessel coronary artery disease (CAD), coronary artery bypass graft (CABG) surgery is the preferred method for revascularization. Patients with DM are at increased risk for diffuse cardiovascular disease due to the proinflammatory, prothrombotic effects of chronic hyperglycemia. In patients undergoing percutaneous coronary intervention, drug-eluting stents and more potent antiplatelet agents especially in those presenting with acute coronary syndromes should be employed.


Subject(s)
Diabetes Mellitus, Type 2/complications , Diabetic Cardiomyopathies/therapy , Myocardial Revascularization/methods , Acute Coronary Syndrome/etiology , Acute Coronary Syndrome/physiopathology , Coronary Artery Bypass/methods , Coronary Artery Disease/etiology , Coronary Artery Disease/physiopathology , Coronary Artery Disease/therapy , Diabetes Mellitus, Type 2/physiopathology , Diabetic Cardiomyopathies/physiopathology , Drug-Eluting Stents , Humans , Percutaneous Coronary Intervention/methods , Platelet Aggregation Inhibitors/therapeutic use
14.
Stud Health Technol Inform ; 192: 627-31, 2013.
Article in English | MEDLINE | ID: mdl-23920632

ABSTRACT

INTRODUCTION: Multi-drug resistant TB (MDR-TB) is a complex infectious disease that is a growing threat to global health. It requires lengthy treatment with multiple drugs and specialized laboratory testing. To effectively scale up treatment to thousands of patients requires good information systems to support clinical care, reporting, drug forecasting, supply chain management and monitoring. METHODS: Over the last decade we have developed the PIH-EMR electronic medical record system, and subsequently OpenMRS-TB, to support the treatment of MDR-TB in Peru, Haiti, Pakistan, and other resource-poor environments. RESULTS: We describe here the experience with implementing these systems and evaluating many aspects of their performance, and review other systems for MDR-TB management. CONCLUSIONS: We recommend a new approach to information systems to address the barriers to scale up MDR-TB treatment, particularly access to the appropriate drugs and lab data. We propose moving away from fragmented, vertical systems to focus on common platforms, addressing all stages of TB care, support for open data standards and interoperability, care for a wide range of diseases including HIV, integration with mHealth applications, and ability to function in resource-poor environments.


Subject(s)
Developing Countries , Electronic Health Records/organization & administration , Extensively Drug-Resistant Tuberculosis/diagnosis , Extensively Drug-Resistant Tuberculosis/therapy , Health Information Management/organization & administration , Medication Systems, Hospital/organization & administration , Remote Consultation/organization & administration , Electronic Prescribing , Haiti , Humans , Pakistan
15.
Regul Toxicol Pharmacol ; 66(1): 13-23, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23454104

ABSTRACT

Glucose oxidase (ß-d-glucose:oxygen 1-oxidoreductase; EC 1.1.2.3.4) is used in the food and beverage industry as a preservative and stabilizer and is commonly derived from the fungus Aspergillus niger. Although the safety of glucose oxidase preparations from A. niger is well-established, the use of preparations derived from other fungal species is of interest; however, an assessment of their safety is warranted. Here, we report on the safety of a glucose oxidase preparation derived from the fungus Penicillium chrysogenum (designated as PGO) for commercial use in food processing, as well as an ingredient in food. In a repeated dose 90-day oral toxicity study conducted in rats, PGO was without compound-related adverse effects at doses of up to 15,600U/kg body weight/day, equivalent to 193mg total organic solids/kg body weight/day. In addition, PGO was non-genotoxic in a series of genotoxicity tests, including a bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, and a combined in vivo mammalian erythrocyte micronucleus test and comet assay. The results of these studies support the safe use of PGO in food for human consumption.


Subject(s)
Food Preservatives/toxicity , Glucose Oxidase/toxicity , Penicillium chrysogenum/chemistry , Administration, Oral , Animals , Dose-Response Relationship, Drug , Female , Food Preservatives/administration & dosage , Food Preservatives/isolation & purification , Glucose Oxidase/administration & dosage , Glucose Oxidase/isolation & purification , Male , Mutagenicity Tests , Rats , Rats, Sprague-Dawley , Toxicity Tests
16.
Curr Opin Cardiol ; 27(6): 669-74, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23032714

ABSTRACT

PURPOSE OF REVIEW: To describe the hazard of in-hospital major bleeding after acute coronary syndromes. RECENT FINDINGS: Long-term complications of early bleeding can extend to over 3 years beyond the index event. Nonaccess-site bleeding accounts for much of the higher risk associated with major in-hospital bleeding. SUMMARY: Bleeding complications after percutaneous coronary intervention are a consistent and independent predictor of adverse clinical outcomes. The majority of complications associated with major bleeding are attributable to in-hospital early bleeds. Whether the link between bleeding and increased mortality is causal has not been established. Bleeding may simply be a marker of higher comorbidity. When possible, bleeding should be avoided, and strategies such as use of risk scores, bivalirudin, vascular closure devices and radial access may decrease major bleeding. In the highest-risk patients, however, bleeding avoidance strategies may not be effective.


Subject(s)
Acute Coronary Syndrome/complications , Angioplasty, Balloon, Coronary/adverse effects , Antithrombins/therapeutic use , Hemorrhage/etiology , Peptide Fragments/therapeutic use , Acute Coronary Syndrome/pathology , Acute Coronary Syndrome/therapy , Hemorrhage/mortality , Hemorrhage/prevention & control , Hirudins , Hospitalization , Humans , Recombinant Proteins/therapeutic use , Risk Factors , Treatment Outcome
17.
Blood ; 120(26): 5103-10, 2012 Dec 20.
Article in English | MEDLINE | ID: mdl-22968458

ABSTRACT

Inorganic polyphosphates are linear polymers of orthophosphate that modulate blood clotting and inflammation. Polyphosphate accumulates in infectious microorganisms and is secreted by activated platelets; long-chain polyphosphate in particular is an extremely potent initiator of the contact pathway, a limb of the clotting cascade important for thrombosis but dispensable for hemostasis. Polyphosphate inhibitors therefore might act as novel antithrombotic/anti-inflammatory agents with reduced bleeding side effects. Antipolyphosphate antibodies are unlikely because of polyphosphate's ubiquity and simple structure; and although phosphatases such as alkaline phosphatase can digest polyphosphate, they take time and may degrade other biologically active molecules. We now identify a panel of polyphosphate inhibitors, including cationic proteins, polymers, and small molecules, and report their effectiveness in vitro and in vivo. We also compare their effectiveness against the procoagulant activity of RNA. Polyphosphate inhibitors were antithrombotic in mouse models of venous and arterial thrombosis and blocked the inflammatory effect of polyphosphate injected intradermally in mice. This study provides proof of principle for polyphosphate inhibitors as antithrombotic/anti-inflammatory agents in vitro and in vivo, with a novel mode of action compared with conventional anticoagulants.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Fibrinolytic Agents/pharmacology , Inflammation/drug therapy , Polyphosphates/antagonists & inhibitors , Thrombosis/drug therapy , Animals , Anti-Inflammatory Agents/isolation & purification , Blood Coagulation/drug effects , Drug Delivery Systems/methods , Drug Discovery , Drug Evaluation, Preclinical , Fibrinolytic Agents/isolation & purification , Hemostasis/drug effects , High-Throughput Screening Assays , Humans , Inflammation/blood , Male , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , Polyphosphates/blood , Thrombosis/blood
18.
Blood ; 119(25): 5972-9, 2012 Jun 21.
Article in English | MEDLINE | ID: mdl-22517894

ABSTRACT

Inorganic polyphosphate is widespread in biology and exhibits striking prohemostatic, prothrombotic, and proinflammatory effects in vivo. Long-chain polyphosphate (of the size present in infectious microorganisms) is a potent, natural pathophysiologic activator of the contact pathway of blood clotting. Medium-chain polyphosphate (of the size secreted from activated human platelets) accelerates factor V activation, completely abrogates the anticoagulant function of tissue factor pathway inhibitor, enhances fibrin clot structure, and greatly accelerates factor XI activation by thrombin. Polyphosphate may have utility as a hemostatic agent, whereas antagonists of polyphosphate may function as novel antithrombotic/anti-inflammatory agents. The detailed molecular mechanisms by which polyphosphate modulates blood clotting reactions remain to be elucidated.


Subject(s)
Blood Coagulation/drug effects , Blood Platelets/drug effects , Inflammation/etiology , Polyphosphates/pharmacology , Animals , Blood Coagulation/physiology , Blood Platelets/metabolism , Blood Platelets/physiology , Fibrin/metabolism , Hemostasis/drug effects , Humans , Inflammation/blood , Inflammation/metabolism , Models, Biological , Platelet Adhesiveness/drug effects , Platelet Adhesiveness/physiology , Polyphosphates/chemistry , Polyphosphates/metabolism , Signal Transduction/drug effects , Signal Transduction/physiology , Thrombin/metabolism
19.
Blood ; 118(26): 6963-70, 2011 Dec 22.
Article in English | MEDLINE | ID: mdl-21976677

ABSTRACT

Factor XI deficiency is associated with a bleeding diathesis, but factor XII deficiency is not, indicating that, in normal hemostasis, factor XI must be activated in vivo by a protease other than factor XIIa. Several groups have identified thrombin as the most likely activator of factor XI, although this reaction is slow in solution. Although certain nonphysiologic anionic polymers and surfaces have been shown to enhance factor XI activation by thrombin, the physiologic cofactor for this reaction is uncertain. Activated platelets secrete the highly anionic polymer polyphosphate, and our previous studies have shown that polyphosphate has potent procoagulant activity. We now report that polyphosphate potently accelerates factor XI activation by α-thrombin, ß-thrombin, and factor XIa and that these reactions are supported by polyphosphate polymers of the size secreted by activated human platelets. We therefore propose that polyphosphate is a natural cofactor for factor XI activation in plasma that may help explain the role of factor XI in hemostasis and thrombosis.


Subject(s)
Factor XI/metabolism , Factor XIa/metabolism , Polyphosphates/pharmacology , Thrombin/pharmacology , Binding, Competitive , Blood Coagulation/drug effects , Blood Platelets/metabolism , Coagulants/metabolism , Coagulants/pharmacology , Drug Synergism , Hemostasis/drug effects , Humans , Platelet Activation , Polyphosphates/metabolism , Protein Binding , Surface Plasmon Resonance , Thrombin/metabolism
20.
Regul Toxicol Pharmacol ; 60(2): 249-61, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21406207

ABSTRACT

Propionibacterium freudenreichii ET-3 culture, a cell-free product of whey fermentation using P. freudenreichii ET-3 (7025), has been shown to promote the growth of Bifidobacteria through the action of 1,4-dihydroxy-2-naphthoic acid (DHNA), and therefore, has potential use in the food and supplement industries. Although currently used as a food ingredient in Japan, the safety of this novel ingredient has not been previously evaluated through traditional toxicity testing. Therefore, here we report the results of standard toxicological testing performed on P. freudenreichii ET-3 culture. In a 4-week oral toxicity study, administration of 6000mg/kg body weight/day P. freudenreichii ET-3 culture was without compound-related adverse effects on clinical signs, body weights, food consumption, ophthalmology, hematology, clinical chemistry, urinalysis, organ weights, and gross and microscopic findings in male and female Sprague-Dawley rats. Furthermore, in vitro mutagenicity testing demonstrated that P. freudenreichii ET-3 culture was non-mutagenic in the bacterial reverse mutation assay using a standard battery of bacterial strains (Salmonella typhimurium TA98, TA100, TA1535, and TA1537 and Escherichia coli WP2 uvrA) and non-clastogenic in Chinese hamster lung cells in the mammalian chromosome aberration test. Together, the results of these studies support the safety of P. freudenreichii ET-3 culture for use in foods for human consumption.


Subject(s)
Mutagenicity Tests/methods , Propionibacterium/metabolism , Toxicity Tests/methods , Animals , Bifidobacterium/growth & development , Cells, Cultured , Chromosome Aberrations , Cricetinae , Cricetulus , Culture Media , Female , Fermentation , Lung/metabolism , Male , Rats , Rats, Sprague-Dawley
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