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1.
Parasit Vectors ; 17(1): 166, 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38556881

ABSTRACT

BACKGROUND: Malaria is a major public health concern in Ethiopia, and its incidence could worsen with the spread of the invasive mosquito species Anopheles stephensi in the country. This study aimed to provide updates on the distribution of An. stephensi and likely household exposure in Ethiopia. METHODS: Entomological surveillance was performed in 26 urban settings in Ethiopia from 2021 to 2023. A kilometer-by-kilometer quadrant was established per town, and approximately 20 structures per quadrant were surveyed every 3 months. Additional extensive sampling was conducted in 50 randomly selected structures in four urban centers in 2022 and 2023 to assess households' exposure to An. stephensi. Prokopack aspirators and CDC light traps were used to collect adult mosquitoes, and standard dippers were used to collect immature stages. The collected mosquitoes were identified to species level by morphological keys and molecular methods. PCR assays were used to assess Plasmodium infection and mosquito blood meal source. RESULTS: Catches of adult An. stephensi were generally low (mean: 0.15 per trap), with eight positive sites among the 26 surveyed. This mosquito species was reported for the first time in Assosa, western Ethiopia. Anopheles stephensi was the predominant species in four of the eight positive sites, accounting for 75-100% relative abundance of the adult Anopheles catches. Household-level exposure, defined as the percentage of households with a peridomestic presence of An. stephensi, ranged from 18% in Metehara to 30% in Danan. Anopheles arabiensis was the predominant species in 20 of the 26 sites, accounting for 42.9-100% of the Anopheles catches. Bovine blood index, ovine blood index and human blood index values were 69.2%, 32.3% and 24.6%, respectively, for An. stephensi, and 65.4%, 46.7% and 35.8%, respectively, for An. arabiensis. None of the 197 An. stephensi mosquitoes assayed tested positive for Plasmodium sporozoite, while of the 1434 An. arabiensis mosquitoes assayed, 62 were positive for Plasmodium (10 for P. falciparum and 52 for P. vivax). CONCLUSIONS: This study shows that the geographical range of An. stephensi has expanded to western Ethiopia. Strongly zoophagic behavior coupled with low adult catches might explain the absence of Plasmodium infection. The level of household exposure to An. stephensi in this study varied across positive sites. Further research is needed to better understand the bionomics and contribution of An. stephensi to malaria transmission.


Subject(s)
Anopheles , Malaria, Falciparum , Malaria, Vivax , Malaria , Animals , Cattle , Ecology , Ethiopia/epidemiology , Malaria/epidemiology , Malaria, Falciparum/epidemiology , Mosquito Vectors
2.
Hear Res ; 430: 108706, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36736160

ABSTRACT

Music is among the most important artistic, cultural, and entertainment modalities in any society. With the proliferation of music genres and the technological advances that allow people to consume music in any location and at any time, music over-exposure has become a significant public health issue. Music-induced hearing loss has a great deal in common with noise-induced hearing loss. However, there are important differences that make music a unique insult to the auditory system and a unique threat to public health. Its unique properties also make it a potentially valuable asset in sound conditioning paradigms. This review discusses hearing loss from noise and music, comparing and contrasting the two. Recent research on music-induced hearing loss is reviewed, followed by discussion of the differences in music-induced hearing loss between performers and consumers. The review concludes with a discussion of the potential of music as a sound conditioning stimulus to protect against acquired hearing loss.


Subject(s)
Deafness , Hearing Loss, Noise-Induced , Music , Humans , Hearing Loss, Noise-Induced/etiology , Hearing Loss, Noise-Induced/prevention & control , Noise/adverse effects , Sound , Leisure Activities , Auditory Threshold
3.
J Ocul Pharmacol Ther ; 38(1): 33-42, 2022.
Article in English | MEDLINE | ID: mdl-35089801

ABSTRACT

The quininib series is a novel collection of small-molecule drugs with antiangiogenic, antivascular permeability, anti-inflammatory, and antiproliferative activity. Quininib was initially identified as a drug hit during a random chemical library screen for determinants of developmental ocular angiogenesis in zebrafish. To enhance drug efficacy, novel quininib analogs were designed by applying medicinal chemistry approaches. The resulting quininib drug series has efficacy in in vitro and ex vivo models of angiogenesis utilizing human cell lines and tissues. In vivo, quininib drugs reduce pathological angiogenesis and retinal vascular permeability in rodent models. Quininib acts as a cysteinyl leukotriene (CysLT) receptor antagonist, revealing new roles of these G-protein-coupled receptors in developmental angiogenesis of the eye and unexpectedly in uveal melanoma (UM). The quininib series highlighted the potential of CysLT receptors as therapeutic targets for retinal vasculopathies (e.g., neovascular age-related macular degeneration, diabetic retinopathy, and diabetic macular edema) and ocular cancers (e.g., UM).


Subject(s)
Angiogenesis Inhibitors/pharmacology , Angiogenesis Inhibitors/therapeutic use , Phenols/pharmacology , Phenols/therapeutic use , Quinolines/pharmacology , Quinolines/therapeutic use , Retinal Diseases/drug therapy , Animals , Diabetic Retinopathy/drug therapy , Disease Models, Animal , Drug Development/methods , Drug Discovery/methods , Eye Neoplasms/drug therapy , Neovascularization, Pathologic/drug therapy , Phenotype , Receptors, Leukotriene/drug effects , Retinal Neovascularization/drug therapy
4.
J Anat ; 240(3): 429-446, 2022 03.
Article in English | MEDLINE | ID: mdl-34693516

ABSTRACT

As a result of many factors, including climate change, unrestricted population growth, widespread deforestation and intensive agriculture, a new pattern of diseases in humans is emerging. With increasing encroachment by human societies into wild domains, the interfaces between human and animal ecosystems are gradually eroding. Such changes have led to zoonoses, vector-borne diseases, infectious diseases and, most importantly, the emergence of antimicrobial-resistant microbial strains as challenges for human health. Now would seem to be an opportune time to revisit old concepts of health and redefine some of these in the light of emerging challenges. The One Health concept addresses some of the demands of modern medical education by providing a holistic approach to explaining diseases that result from a complex set of interactions between humans, environment and animals, rather than just an amalgamation of isolated signs and symptoms. An added advantage is that the scope of One Health concepts has now expanded to include genetic diseases due to advancements in omics technology. Inspired by such ideas, a symposium was organised as part of the 19th International Federation of Associations of Anatomists (IFAA) Congress (August 2019) to investigate the scope of One Health concepts and comparative anatomy in contemporary medical education. Speakers with expertise in both human and veterinary anatomy participated in the symposium and provided examples where these two disciplines, which have so far evolved largely independent of each other, can collaborate for mutual benefit. Finally, the speakers identified some key concepts of One Health that should be prioritised and discussed the diverse opportunities available to integrate these priorities into a broader perspective that would attempt to explain and manage diseases within the scopes of human and veterinary medicine.


Subject(s)
Anatomy , Education, Medical , One Health , Anatomy/education , Anatomy, Comparative , Animals , Ecosystem
5.
Front Neurosci ; 15: 784987, 2021.
Article in English | MEDLINE | ID: mdl-34867178

ABSTRACT

Optic atrophy (OA) with autosomal inheritance is a form of optic neuropathy characterized by the progressive and irreversible loss of vision. In some cases, this is accompanied by additional, typically neurological, extra-ocular symptoms. Underlying the loss of vision is the specific degeneration of the retinal ganglion cells (RGCs) which form the optic nerve. Whilst autosomal OA is genetically heterogenous, all currently identified causative genes appear to be associated with mitochondrial organization and function. However, it is unclear why RGCs are particularly vulnerable to mitochondrial aberration. Despite the relatively high prevalence of this disorder, there are currently no approved treatments. Combined with the lack of knowledge concerning the mechanisms through which aberrant mitochondrial function leads to RGC death, there remains a clear need for further research to identify the underlying mechanisms and develop treatments for this condition. This review summarizes the genes known to be causative of autosomal OA and the mitochondrial dysfunction caused by pathogenic mutations. Furthermore, we discuss the suitability of available in vivo models for autosomal OA with regards to both treatment development and furthering the understanding of autosomal OA pathology.

6.
BMJ Open Sci ; 5(1): e100240, 2021.
Article in English | MEDLINE | ID: mdl-34849404

ABSTRACT

INTRODUCTION: Impaired lipid metabolism in the renal tubule plays a prominent role in the progression of renal fibrosis following acute kidney injury (AKI) and in chronic kidney disease (CKD). Peroxisome proliferator-activated receptors (PPARs) are promising druggable targets to mitigate renal fibrosis by redirecting metabolism, including restoration of fatty acid oxidation (FAO) capacity. We aim to synthesise evidence from preclinical studies of pharmacological PPAR targeting in experimental renal injury, and inform the design of future studies evaluating PPAR-mediated restoration of FAO in AKI and CKD. METHODS AND ANALYSIS: Studies reporting on the impact of pharmacological PPAR modulation in animal models of renal injury will be collected from MEDLINE (Ovid), Embase and Web of Science databases. Predefined eligibility criteria will exclude studies testing medications which are not specific ligands of one or more PPARs and studies involving multimodal pharmacological treatment. The Systematic Review Centre for Laboratory Animal Experimentation risk of bias tool and Collaborative Approach to Meta-Analysis and Review of Animal Experimental Studies checklist will be used to assess quality of the included studies. Data extraction will be followed by a narrative synthesis of the data and meta-analysis where feasible. Analysis will be performed separately for AKI, CKD and renal transplant models. Subgroup analyses will be performed based on study design characteristics, PPAR isotype(s) targeted, and classes of PPAR-targeting medications used. Risk of publication bias will be assessed using funnel plotting, Egger's regression and trim-and-fill analysis. ETHICS AND DISSEMINATION: Ethical approval is not required. Findings will be published in a peer-reviewed journal and presented at scientific meetings. PROSPERO REGISTRATION NUMBER: CRD42021265550.

7.
Biology (Basel) ; 9(5)2020 May 01.
Article in English | MEDLINE | ID: mdl-32370057

ABSTRACT

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), is a selective anticancer cytokine capable of exerting a targeted therapy approach. Disappointingly, recent research has highlighted the development of TRAIL resistance in cancer cells, thus minimising its usefulness in clinical settings. However, several recent studies have demonstrated that cancer cells can be sensitised to TRAIL through the employment of a combinatorial approach, utilizing TRAIL in conjunction with other natural or synthetic anticancer agents. In the present study, the chemo-sensitising effect of curcumin on TRAIL-induced apoptosis in renal carcinoma cells (RCC) was investigated. The results indicate that exposure of kidney cancer ACHN cells to curcumin sensitised the cells to TRAIL, with the combination treatment of TRAIL and curcumin synergistically targeting the cancer cells without affecting the normal renal proximal tubular epithelial cells (RPTEC/TERT1) cells. Furthermore, this combination treatment was shown to induce caspase-dependent apoptosis, inhibition of the proteasome, induction of ROS, upregulation of death receptor 4 (DR4), alterations in mitogen-activated protein kinase (MAPK) signalling and induction of endoplasmic reticulum stress. An in vivo zebrafish embryo study demonstrated the effectiveness of the combinatorial regime to inhibit tumour formation without affecting zebrafish embryo viability or development. Overall, the results arising from this study demonstrate that curcumin has the ability to sensitise TRAIL-resistant ACHN cells to TRAIL-induced apoptosis.

8.
Dev Biol ; 457(2): 226-234, 2020 01 15.
Article in English | MEDLINE | ID: mdl-30825427

ABSTRACT

Von Hippel-Lindau (VHL) syndrome is a rare, autosomal dominant disorder, characterised by hypervascularised tumour formation in multiple organ systems. Vision loss associated with retinal capillary hemangioblastomas remains one of the earliest complications of VHL disease. The mortality of Vhl-/- mice in utero restricted modelling of VHL disease in this mammalian model. Zebrafish harbouring a recessive germline mutation in the vhl gene represent a viable, alternative vertebrate model to investigate associated ocular loss-of-function phenotypes. Previous studies reported neovascularisation of the brain, eye and trunk together with oedema in the vhl-/- zebrafish eye. In this study, we demonstrate vhl-/- zebrafish almost entirely lack visual function. Furthermore, hyaloid vasculature networks in the vhl-/- eye are improperly formed and this phenotype is concomitant with development of an ectopic intraretinal vasculature. Sunitinib malate, a multi tyrosine kinase inhibitor, market authorised for cancer, reversed the ocular behavioural and morphological phenotypes observed in vhl-/- zebrafish. We conclude that the zebrafish vhl gene contributes to an endogenous molecular barrier that prevents development of intraretinal vasculature, and that pharmacological intervention with sunitinib can improve visual function and hyaloid vessel patterning while reducing abnormally formed ectopic intraretinal vessels in vhl-/- zebrafish.


Subject(s)
Eye/blood supply , Retina/embryology , Tumor Suppressor Proteins/genetics , Zebrafish Proteins/genetics , Zebrafish/genetics , von Hippel-Lindau Disease/genetics , Animals , Antineoplastic Agents/pharmacology , Blindness/genetics , Disease Models, Animal , Eye/embryology , Hemangioblastoma/genetics , Sunitinib/pharmacology , Vision, Ocular/genetics , von Hippel-Lindau Disease/pathology , von Hippel-Lindau Disease/prevention & control
9.
Adv Exp Med Biol ; 1185: 263-267, 2019.
Article in English | MEDLINE | ID: mdl-31884622

ABSTRACT

Worldwide, 1 in 2000 people suffer from inherited retinal dystrophies (IRD). Individuals with IRD typically present with progressive vision loss that ultimately results in blindness. Unfortunately, effective treatment options are not widely available due to the genetic and clinical heterogeneity of these diseases. There are multiple gene, cell, and drug-based therapies in various phases of clinical trials for IRD. This mini-review documents current progress made in drug-based clinical trials for treating IRD.


Subject(s)
Drug Development , Retinal Dystrophies/drug therapy , Clinical Trials as Topic , Humans
10.
Nanotoxicology ; 13(6): 717-732, 2019 08.
Article in English | MEDLINE | ID: mdl-31111769

ABSTRACT

Careful handling of the nanomaterials (NMs) in research labs is crucial to ensure a safe working environment. As the largest university in Ireland, University College Dublin (UCD) has invested significant resources to update researchers working with NMs. Due to sizes often <100 nm, the NMs including nanoparticles, harbor unprecedented materialistic properties, for example, enhanced reactivity, conductivity, fluorescence, etc. which albeit conferring the NMs an edge over bulk materials regarding the applied aspects; depending on the dose, also render them to be toxic. Thus, a set of regulatory guidelines have emerged regarding safe handling of the NMs within occupational set-ups. Unfortunately, the current regulations based on the toxic chemicals and carcinogens are often confusing, lack clarity, and difficult to apply for the NMs. As a research-intensive university, a diverse range of research activities occur within the UCD labs, and it is difficult, at times impossible, for the UCD Safety, Insurance, Operational Risk & Compliance (SIRC) office to develop a set of common guidelines and cater throughout all its labs conducting research with the NMs. Hence, a necessity for dialog and exchange of ideas was felt across the UCD which encouraged the researchers including early stage researchers (e.g. PhDs, Postdocs) from multiple schools to participate in a workshop held on the 03 December 2018. The workshop tried to follow a pragmatic approach, where apart from discussing both the in vitro and in vivo scenarios, practical cases simulating situations faced frequently in the labs were discussed. This report summarizes the findings made during the workshop by this emerging critical mass in UCD.


Subject(s)
Laboratories/standards , Nanostructures/toxicity , Occupational Exposure/prevention & control , Safety Management/standards , Specimen Handling/standards , Universities , Consensus Development Conferences as Topic , Guidelines as Topic , Humans , Ireland
11.
Cancer Lett ; 447: 115-129, 2019 04 10.
Article in English | MEDLINE | ID: mdl-30664962

ABSTRACT

Oesophageal adenocarcinoma (OAC) is an aggressive disease with 5-year survival rates of <20%. Only 20-30% OAC patients show a beneficial response to neoadjuvant therapy. Altered mitochondrial function is linked with radioresistance in OAC. We identified pyrazinib (P3), a pyrazine phenol small molecule drug with anti-angiogenic and anti-metabolic activity in-vivo in zebrafish and in-vitro isogenic models of OAC radioresistance. Pyrazinib (P3) significantly inhibited blood vessel development in zebrafish (p < 0.001). In-vivo in zebrafish and in-vitro in an isogenic model of OAC radioresistance, pyrazinib (P3) significantly reduced measures of oxidative phosphorylation and glycolysis. Pyrazinib (P3) significantly reduced the surviving fraction in OE33P; radiation-sensitive and OE33R; radiation-resistant cells following irradiation. Under hypoxic conditions pyrazinib (P3) significantly reduced OE33R cell survival following 4 Gy irradiation (p = 0.0216). Multiplex ELISA showed significantly higher secreted levels of 9 of 30 detected inflammatory and angiogenic factors in OE33R radioresistant cells compared to OE33P cells; IL-8, IL-4, IL-6, IL-2, IL-12p70, IL-10, MCP-1, IP-10, ICAM (p < 0.05). Pyrazinib (P3) significantly reduced the secretions of IL-6 (p = 0.0006), IL-8 (p = 0.0488), and IL-4 (p = 0.0111) in OE33R cells. Collectively, these findings support further development of pyrazinib (P3) as a novel therapeutic radiosensitiser in OAC.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Agents/pharmacology , Esophageal Neoplasms/drug therapy , Phenols/pharmacology , Pyrazines/pharmacology , Radiation Tolerance/drug effects , Radiation-Sensitizing Agents/pharmacology , Small Molecule Libraries/pharmacology , Animals , Cell Line, Tumor , Cell Survival/drug effects , Humans , Neoadjuvant Therapy/methods , Zebrafish
12.
Adv Exp Med Biol ; 1074: 465-471, 2018.
Article in English | MEDLINE | ID: mdl-29721977

ABSTRACT

This review discusses the therapeutic potential of brain-derived neurotrophic factor (BDNF) for retinal degeneration. BDNF, nerve growth factor (NGF), neurotrophin 3 (NT-3) and NT-4/NT-5 belong to the neurotrophin family. These neuronal modulators activate a common receptor and a specific tropomyosin-related kinase (Trk) receptor. BDNF was identified as a photoreceptor protectant in models of retinal degeneration as early as 1992. However, development of effective therapeutics that exploit this pathway has been difficult due to challenges in sustaining therapeutic levels in the retina.


Subject(s)
Brain-Derived Neurotrophic Factor/therapeutic use , Neuroprotective Agents/therapeutic use , Retinal Degeneration/drug therapy , Animals , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/pharmacokinetics , Cell Survival/drug effects , Dependovirus/genetics , Disease Models, Animal , Drug Evaluation, Preclinical , Genetic Therapy , Genetic Vectors/therapeutic use , Humans , Mice , Neuroprotective Agents/pharmacokinetics , Photoreceptor Cells, Vertebrate/drug effects , Rats , Recombinant Proteins/pharmacokinetics , Recombinant Proteins/therapeutic use , Retinal Degeneration/prevention & control , Retinal Degeneration/therapy
13.
Sci Rep ; 7(1): 11320, 2017 09 12.
Article in English | MEDLINE | ID: mdl-28900183

ABSTRACT

Controversially, histone deacetylase inhibitors (HDACi) are in clinical trial for the treatment of inherited retinal degeneration. Utilizing the zebrafish dye ucd6 model, we determined if treatment with HDACi can rescue cone photoreceptor-mediated visual function. dye exhibit defective visual behaviour and retinal morphology including ciliary marginal zone (CMZ) cell death and decreased photoreceptor outer segment (OS) length, as well as gross morphological defects including hypopigmentation and pericardial oedema. HDACi treatment of dye results in significantly improved optokinetic (OKR) (~43 fold, p < 0.001) and visualmotor (VMR) (~3 fold, p < 0.05) responses. HDACi treatment rescued gross morphological defects and reduced CMZ cell death by 80%. Proteomic analysis of dye eye extracts suggested BDNF-TrkB and Akt signaling as mediators of HDACi rescue in our dataset. Co-treatment with the TrkB antagonist ANA-12 blocked HDACi rescue of visual function and associated Akt phosphorylation. Notably, sole treatment with a BDNF mimetic, 7,8-dihydroxyflavone hydrate, significantly rescued dye visual function (~58 fold increase in OKR, p < 0.001, ~3 fold increase in VMR, p < 0.05). In summary, HDACi and a BDNF mimetic are sufficient to rescue retinal cell death and visual function in a vertebrate model of inherited blindness.


Subject(s)
Blindness/physiopathology , Brain-Derived Neurotrophic Factor/metabolism , Genetic Diseases, Inborn/physiopathology , Molecular Mimicry , Retinal Cone Photoreceptor Cells/metabolism , Vision, Ocular , Animals , Blindness/diagnosis , Blindness/drug therapy , Blindness/genetics , Brain-Derived Neurotrophic Factor/pharmacology , Disease Models, Animal , Electroretinography , Genetic Diseases, Inborn/diagnosis , Genetic Diseases, Inborn/drug therapy , Genetic Diseases, Inborn/genetics , Histone Deacetylase Inhibitors/pharmacology , Male , Mutation , Proteome , Proteomics/methods , Receptor, trkB/metabolism , Retina/drug effects , Retina/metabolism , Retina/pathology , Retinal Cone Photoreceptor Cells/drug effects , Signal Transduction , Vision, Ocular/drug effects , Vision, Ocular/genetics , Zebrafish , Zebrafish Proteins/chemistry , Zebrafish Proteins/genetics , Zebrafish Proteins/metabolism
14.
J Biol Chem ; 292(9): 3552-3567, 2017 03 03.
Article in English | MEDLINE | ID: mdl-28035003

ABSTRACT

Excess blood vessel growth contributes to the pathology of metastatic cancers and age-related retinopathies. Despite development of improved treatments, these conditions are associated with high economic costs and drug resistance. Bevacizumab (Avastin®), a monoclonal antibody against vascular endothelial growth factor (VEGF), is used clinically to treat certain types of metastatic cancers. Unfortunately, many patients do not respond or inevitably become resistant to bevacizumab, highlighting the need for more effective antiangiogenic drugs with novel mechanisms of action. Previous studies discovered quininib, an antiangiogenic small molecule antagonist of cysteinyl leukotriene receptors 1 and 2 (CysLT1 and CysLT2). Here, we screened a series of quininib analogues and identified a more potent antiangiogenic novel chemical entity (IUPAC name (E)-2-(2-quinolin-2-yl-vinyl)-benzene-1,4-diol HCl) hereafter designated Q8. Q8 inhibits developmental angiogenesis in Tg(fli1:EGFP) zebrafish and inhibits human microvascular endothelial cell (HMEC-1) proliferation, tubule formation, and migration. Q8 elicits antiangiogenic effects in a VEGF-independent in vitro model of angiogenesis and exerts an additive antiangiogenic response with the anti-VEGF biologic bevacizumab. Cell-based receptor binding assays confirm that Q8 is a CysLT1 antagonist and is sufficient to reduce cellular levels of NF-κB and calpain-2 and secreted levels of the proangiogenic proteins intercellular adhesion molecule-1, vascular cell adhesion protein-1, and VEGF. Distinct reductions of VEGF by bevacizumab explain the additive antiangiogenic effects observed in combination with Q8. In summary, Q8 is a more effective antiangiogenic drug compared with quininib. The VEGF-independent activity coupled with the additive antiangiogenic response observed in combination with bevacizumab demonstrates that Q8 offers an alternative therapeutic strategy to combat resistance associated with conventional anti-VEGF therapies.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Benzene Derivatives/pharmacology , Bevacizumab/pharmacology , Cysteine/chemistry , Leukotriene Antagonists/pharmacology , Neovascularization, Pathologic/metabolism , Phenols/pharmacology , Quinolines/pharmacology , Animals , Animals, Genetically Modified , Cell Line , Cell Movement , Cell Survival , Dose-Response Relationship, Drug , Endothelial Cells/cytology , Endothelial Cells/drug effects , Green Fluorescent Proteins/metabolism , Humans , Microscopy, Fluorescence , Recombinant Proteins/metabolism , Signal Transduction , Vascular Endothelial Growth Factor A/metabolism , Zebrafish
15.
Sci Rep ; 6: 34523, 2016 10 14.
Article in English | MEDLINE | ID: mdl-27739445

ABSTRACT

Colorectal cancer (CRC) is a leading cause of cancer deaths. Molecularly targeted therapies (e.g. bevacizumab) have improved survival rates but drug resistance ultimately develops and newer therapies are required. We identified quininib as a small molecule drug with anti-angiogenic activity using in vitro, ex vivo and in vivo screening models. Quininib (2-[(E)-2-(Quinolin-2-yl) vinyl] phenol), is a small molecule drug (molecular weight 283.75 g/mol), which significantly inhibited blood vessel development in zebrafish embryos (p < 0.001). In vitro, quininib reduced endothelial tubule formation (p < 0.001), cell migration was unaffected by quininib and cell survival was reduced by quininib (p < 0.001). Using ex vivo human CRC explants, quininib significantly reduced the secretions of IL-6, IL-8, VEGF, ENA-78, GRO-α, TNF, IL-1ß and MCP-1 ex vivo (all values p < 0.01). Quininib is well tolerated in mice when administered at 50 mg/kg intraperitoneally every 3 days and significantly reduced tumour growth of HT-29-luc2 CRC tumour xenografts compared to vehicle control. In addition, quininib reduced the signal from a αvß3 integrin fluorescence probe in tumours 10 days after treatment initiation, indicative of angiogenic inhibition. Furthermore, quininib reduced the expression of angiogenic genes in xenografted tumours. Collectively, these findings support further development of quininib as a novel therapeutic agent for CRC.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antineoplastic Agents/therapeutic use , Colorectal Neoplasms/drug therapy , Neovascularization, Pathologic/metabolism , Phenols/therapeutic use , Quinolines/therapeutic use , Animals , Blood Vessels/drug effects , Cell Line , Colorectal Neoplasms/complications , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Endothelial Cells/drug effects , Gene Expression , HT29 Cells , Humans , Inflammation Mediators/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Mice, Inbred BALB C , Neovascularization, Pathologic/complications , Vascular Endothelial Growth Factor A/metabolism , Xenograft Model Antitumor Assays , Zebrafish
16.
Br J Nurs ; 25(13): 729-33, 2016 Jul 14.
Article in English | MEDLINE | ID: mdl-27409780

ABSTRACT

The aim of this study was to explore nurses' experience of using leech therapy. Leech therapy is useful in promoting revascularisation of skin grafts. Nurse disquiet in their role as leech therapists has been noted. This study explored the experience of Irish nurses. A qualitative design with an interview schedule was used to learn about emotional and practical clinical experiences. Interviews were carried out with seven nurses working with leeches in reconstructive surgery in 2013. These interviews were coded and explored for themes. Results revealed that many nurses feel aversion to the use of leeches. This may be associated with the use of a parasitic organism as treatment in conflict with the nurse's role in cross infection. It was also found that management of a nurse's own and patient's emotional responses is required. In conclusion, preparation for the role of leech therapy beyond the purely practical is necessary, and should explore affective responses of the practitioner and patients.


Subject(s)
Attitude of Health Personnel , Leeching/nursing , Nurses/psychology , Plastic Surgery Procedures/nursing , Skin Transplantation/nursing , Surgery, Plastic/nursing , Humans , Ireland , Qualitative Research
17.
J Control Release ; 233: 198-207, 2016 07 10.
Article in English | MEDLINE | ID: mdl-27086168

ABSTRACT

Pathologic neovascularisation and ocular permeability are hallmarks of proliferative diabetic retinopathy and age-related macular degeneration. Current pharmacologic interventions targeting VEGF are effective in only 30-60% of patients and require multiple intraocular injections associated with iatrogenic infection. Thus, our goal is to develop novel small molecule drugs that are VEGF-independent are amenable to sustained ocular-release, and which reduce retinal angiogenesis and retinal vascular permeability. Here, the anti-angiogenic drug quininib was formulated into hyaluronan (HA) microneedles whose safety and efficacy was evaluated in vivo. Quininib-HA microneedles were formulated via desolvation from quininib-HA solution and subsequent cross-linking with 4-arm-PEG-amine prior to freeze-drying. Scanning electron microscopy revealed hollow needle-shaped particle ultrastructure, with a zeta potential of -35.5mV determined by electrophoretic light scattering. The incorporation efficiency and pharmacokinetic profile of quininib released in vitro from the microneedles was quantified by HPLC. Quininib incorporation into these microneedles was 90%. In vitro, 20% quininib was released over 4months; or in the presence of increasing concentrations of hyaluronidase, 60% incorporated quininib was released over 4months. Zebrafish hyaloid vasculature assays demonstrated quininib released from these microneedles significantly (p<0.0001) inhibited ocular developmental angiogenesis compared to control. Sustained amelioration of retinal vascular permeability (RVP) was demonstrated using a bespoke cysteinyl leukotriene induced rodent model. Quininib-HA microparticles significantly inhibited RVP in Brown Norway rats one month after administration compared to neat quininib control (p=0.0071). In summary, quininib-HA microneedles allow for sustained release of quininib; are safe in vivo and quininib released from these microneedles effectively inhibits angiogenesis and RVP in vivo.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Drug Delivery Systems , Hyaluronic Acid/administration & dosage , Phenols/administration & dosage , Quinolines/administration & dosage , Retinal Neovascularization/drug therapy , Angiogenesis Inhibitors/therapeutic use , Animals , Animals, Genetically Modified , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/therapeutic use , Green Fluorescent Proteins/genetics , Hyaluronic Acid/therapeutic use , Intravitreal Injections , Larva , Male , Permeability/drug effects , Phenols/therapeutic use , Quinolines/therapeutic use , Rats, Sprague-Dawley , Retina/drug effects , Retina/metabolism , Retinal Neovascularization/metabolism , Zebrafish/genetics
18.
J Biol Chem ; 291(14): 7242-55, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-26846851

ABSTRACT

Retinal angiogenesis is tightly regulated to meet oxygenation and nutritional requirements. In diseases such as proliferative diabetic retinopathy and neovascular age-related macular degeneration, uncontrolled angiogenesis can lead to blindness. Our goal is to better understand the molecular processes controlling retinal angiogenesis and discover novel drugs that inhibit retinal neovascularization. Phenotype-based chemical screens were performed using the ChemBridge Diverset(TM)library and inhibition of hyaloid vessel angiogenesis in Tg(fli1:EGFP) zebrafish. 2-[(E)-2-(Quinolin-2-yl)vinyl]phenol, (quininib) robustly inhibits developmental angiogenesis at 4-10 µmin zebrafish and significantly inhibits angiogenic tubule formation in HMEC-1 cells, angiogenic sprouting in aortic ring explants, and retinal revascularization in oxygen-induced retinopathy mice. Quininib is well tolerated in zebrafish, human cell lines, and murine eyes. Profiling screens of 153 angiogenic and inflammatory targets revealed that quininib does not directly target VEGF receptors but antagonizes cysteinyl leukotriene receptors 1 and 2 (CysLT1-2) at micromolar IC50values. In summary, quininib is a novel anti-angiogenic small-molecule CysLT receptor antagonist. Quininib inhibits angiogenesis in a range of cell and tissue systems, revealing novel physiological roles for CysLT signaling. Quininib has potential as a novel therapeutic agent to treat ocular neovascular pathologies and may complement current anti-VEGF biological agents.


Subject(s)
Angiogenesis Inhibitors , Drug Discovery , Phenols , Quinolines , Retinal Neovascularization/drug therapy , Signal Transduction/drug effects , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/pharmacokinetics , Angiogenesis Inhibitors/pharmacology , Animals , Animals, Genetically Modified , Cell Line , Diabetic Retinopathy/drug therapy , Diabetic Retinopathy/metabolism , Humans , Macular Degeneration/drug therapy , Macular Degeneration/metabolism , Mice , Phenols/chemistry , Phenols/pharmacokinetics , Phenols/pharmacology , Receptors, Vascular Endothelial Growth Factor/antagonists & inhibitors , Retinal Neovascularization/metabolism , Retinal Neovascularization/pathology , Zebrafish
20.
Lancet Infect Dis ; 15(7): 825-32, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25921597

ABSTRACT

BACKGROUND: The ongoing Ebola epidemic in parts of west Africa largely overwhelmed health-care systems in 2014, making adequate care for malaria impossible and threatening the gains in malaria control achieved over the past decade. We quantified this additional indirect burden of Ebola virus disease. METHODS: We estimated the number of cases and deaths from malaria in Guinea, Liberia, and Sierra Leone from Demographic and Health Surveys data for malaria prevalence and coverage of malaria interventions before the Ebola outbreak. We then removed the effect of treatment and hospital care to estimate additional cases and deaths from malaria caused by reduced health-care capacity and potential disruption of delivery of insecticide-treated bednets. We modelled the potential effect of emergency mass drug administration in affected areas on malaria cases and health-care demand. FINDINGS: If malaria care ceased as a result of the Ebola epidemic, untreated cases of malaria would have increased by 45% (95% credible interval 43-49) in Guinea, 88% (83-93) in Sierra Leone, and 140% (135-147) in Liberia in 2014. This increase is equivalent to 3·5 million (95% credible interval 2·6 million to 4·9 million) additional untreated cases, with 10,900 (5700-21,400) additional malaria-attributable deaths. Mass drug administration and distribution of insecticide-treated bednets timed to coincide with the 2015 malaria transmission season could largely mitigate the effect of Ebola virus disease on malaria. INTERPRETATION: These findings suggest that untreated malaria cases as a result of reduced health-care capacity probably contributed substantially to the morbidity caused by the Ebola crisis. Mass drug administration can be an effective means to mitigate this burden and reduce the number of non-Ebola fever cases within health systems. FUNDING: UK Medical Research Council, UK Department for International Development, Bill & Melinda Gates Foundation.


Subject(s)
Cost of Illness , Developing Countries , Epidemics , Health Resources/statistics & numerical data , Hemorrhagic Fever, Ebola/epidemiology , Malaria/mortality , Adolescent , Child , Child, Preschool , Guinea/epidemiology , Health Resources/supply & distribution , Health Services Accessibility , Hemorrhagic Fever, Ebola/therapy , Humans , Insecticide-Treated Bednets/supply & distribution , Liberia/epidemiology , Malaria/drug therapy , Malaria/prevention & control , Models, Theoretical , Sierra Leone/epidemiology
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