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1.
J Thromb Haemost ; 22(3): 633-644, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38016519

RESUMO

BACKGROUND: Laboratory resurrection of ancient coagulation factor (F) IX variants generated through ancestral sequence reconstruction led to the discovery of a FIX variant, designated An96, which possesses enhanced specific activity independent of and additive to that provided by human p.Arg384Lys, referred to as FIX-Padua. OBJECTIVES: The goal of the current study was to identify the amino acid substitution(s) responsible for the enhanced activity of An96 and create a humanized An96 FIX transgene for gene therapy application. METHODS: Reductionist screening approaches, including domain swapping and scanning residue substitution, were used and guided by one-stage FIX activity assays. In vitro characterization of top candidates included recombinant high-purity preparation, specific activity determination, and enzyme kinetic analysis. Final candidates were packaged into adeno-associated viral (AAV) vectors and delivered to hemophilia B mice. RESULTS: Five of 42 total amino acid substitutions in An96 appear sufficient to retain the enhanced activity of An96 in an otherwise human FIX variant. Additional substitution of the Padua variant further increased the specific activity 5-fold. This candidate, designated ET9, demonstrated 51-fold greater specific activity than hFIX. AAV2/8-ET9 treated hemophilia B mice produced plasma FIX activities equivalent to those observed previously for AAV2/8-An96-Padua, which were 10-fold higher than AAV2/8-hFIX-Padua. CONCLUSION: Starting from computationally inferred ancient FIX sequences, novel amino acid substitutions conferring activity enhancement were identified and translated into an AAV-FIX gene therapy cassette demonstrating high potency. This ancestral sequence reconstruction discovery and sequence mapping refinement approach represents a promising platform for broader protein drug and gene therapy candidate optimization.


Assuntos
Fator IX , Hemofilia B , Humanos , Camundongos , Animais , Fator IX/metabolismo , Hemofilia B/terapia , Hemofilia B/tratamento farmacológico , Cinética , Terapia Genética , Substituição de Aminoácidos , Vetores Genéticos , Dependovirus/genética , Dependovirus/metabolismo
2.
Blood Adv ; 5(17): 3333-3343, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34477814

RESUMO

Orthologous proteins contain sequence disparity guided by natural selection. In certain cases, species-specific protein functionality predicts pharmacological enhancement, such as greater specific activity or stability. However, immunological barriers generally preclude use of nonhuman proteins as therapeutics, and difficulty exists in the identification of individual sequence determinants among the overall sequence disparity. Ancestral sequence reconstruction (ASR) represents a platform for the prediction and resurrection of ancient gene and protein sequences. Recently, we demonstrated that ASR can be used as a platform to facilitate the identification of therapeutic protein variants with enhanced properties. Specifically, we identified coagulation factor VIII (FVIII) variants with improved specific activity, biosynthesis, stability, and resistance to anti-human FVIII antibody-based inhibition. In the current study, we resurrected a panel of ancient mammalian coagulation factor IX (FIX) variants with the goal of identifying improved pharmaceutical candidates. One variant (An96) demonstrated 12-fold greater FIX activity production than human FIX. Addition of the R338L Padua substitution further increased An96 activity, suggesting independent but additive mechanisms. after adeno-associated virus 2 (AAV2)/8-FIX gene therapy, 10-fold greater plasma FIX activity was observed in hemophilia B mice administered AAV2/8-An96-Padua as compared with AAV2/8-human FIX-Padua. Furthermore, phenotypic correction conferred by the ancestral variant was confirmed using a saphenous vein bleeding challenge and thromboelastography. Collectively, these findings validate the ASR drug discovery platform as well as identify an ancient FIX candidate for pharmaceutical development.


Assuntos
Fator IX , Hemofilia B , Animais , Testes de Coagulação Sanguínea , Fator IX/genética , Terapia Genética , Hemofilia B/genética , Hemofilia B/terapia , Hemorragia , Camundongos
3.
Blood Adv ; 5(3): 812-822, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560395

RESUMO

Ancestral sequence reconstruction provides a unique platform for investigating the molecular evolution of single gene products and recently has shown success in engineering advanced biological therapeutics. To date, the coevolution of proteins within complexes and protein-protein interactions is mostly investigated in silico via proteomics and/or within single-celled systems. Herein, ancestral sequence reconstruction is used to investigate the molecular evolution of 2 proteins linked not only by stabilizing association in circulation but also by their independent roles within the primary and secondary hemostatic systems of mammals. Using sequence analysis and biochemical characterization of recombinant ancestral von Willebrand factor (VWF) and coagulation factor VIII (FVIII), we investigated the evolution of the essential macromolecular FVIII/VWF complex. Our data support the hypothesis that these coagulation proteins coevolved throughout mammalian diversification, maintaining strong binding affinities while modulating independent and distinct hemostatic activities in diverse lineages.


Assuntos
Fator VIII , Fator de von Willebrand , Animais , Fator VIII/genética , Hemostasia , Fator de von Willebrand/genética
4.
J Thromb Haemost ; 18(1): 57-69, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31454152

RESUMO

BACKGROUND: Coagulation factor VIII represents one of the oldest protein-based therapeutics, serving as an effective hemophilia A treatment for half a century. Optimal treatment consists of repeated intravenous infusions of blood coagulation factor VIII (FVIII) per week for life. Despite overall treatment success, significant limitations remain, including treatment invasiveness, duration, immunogenicity, and cost. These issues have inspired research into the development of bioengineered FVIII products and gene therapies. OBJECTIVES: To structurally characterize a bioengineered construct of FVIII, termed ET3i, which is a human/porcine chimeric B domain-deleted heterodimer with improved expression and slower A2 domain dissociation following proteolytic activation by thrombin. METHODS: The structure of ET3i was characterized with X-ray crystallography and tandem mass spectrometry-based glycoproteomics. RESULTS: Here, we report the 3.2 Å crystal structure of ET3i and characterize the distribution of N-linked glycans with LC-MS/MS glycoproteomics. This structure shows remarkable conservation with the human FVIII protein and provides a detailed view of the interface between the A2 domain and the remaining FVIII structure. With two FVIII molecules in the crystal, we observe two conformations of the C2 domain relative to the remaining FVIII structure. The improved model and stereochemistry of ET3i served as a scaffold to generate an improved, refined structure of human FVIII. With the original datasets at 3.7 Å and 4.0 Å resolution, this new structure resulted in improved refinement statistics. CONCLUSIONS: These improved structures yield a more confident model for next-generation engineering efforts to develop FVIII therapeutics with longer half-lives, higher expression levels, and lower immunogenicity.


Assuntos
Fator VIII/química , Hemofilia A , Animais , Domínios C2 , Cromatografia Líquida , Hemofilia A/tratamento farmacológico , Humanos , Engenharia de Proteínas , Proteínas Recombinantes/química , Suínos , Espectrometria de Massas em Tandem
5.
Lancet ; 394(10214): 2084-2095, 2019 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-31791688

RESUMO

BACKGROUND: Carboplatin and paclitaxel administered every 3 weeks is standard-of-care first-line chemotherapy for epithelial ovarian cancer. The Japanese JGOG3016 trial showed a significant improvement in progression-free and overall survival with dose-dense weekly paclitaxel and 3-weekly carboplatin. In this study, we aimed to compare efficacy and safety of two dose-dense weekly regimens to standard 3-weekly chemotherapy in a predominantly European population with epithelial ovarian cancer. METHODS: In this phase 3 trial, women with newly diagnosed International Federation of Gynecology and Obstetrics stage IC-IV epithelial ovarian cancer were randomly assigned to group 1 (carboplatin area under the curve [AUC]5 or AUC6 and 175 mg/m2 paclitaxel every 3 weeks), group 2 (carboplatin AUC5 or AUC6 every 3 weeks and 80 mg/m2 paclitaxel weekly), or group 3 (carboplatin AUC2 and 80 mg/m2 paclitaxel weekly). Written informed consent was provided by all women who entered the trial. The protocol had the appropriate national research ethics committee approval for the countries where the study was conducted. Patients entered the trial after immediate primary surgery, or before neoadjuvant chemotherapy with subsequent planned delayed primary surgery. The trial coprimary outcomes were progression-free survival and overall survival. Data analyses were done on an intention-to-treat basis, and were powered to detect a hazard ratio of 0·75 in progression-free survival. The main comparisons were between the control group (group 1) and each of the weekly research groups (groups 2 and 3). FINDINGS: Between June 6, 2011, and Nov 28, 2014, 1566 women were randomly assigned to treatment. 72% (365), completed six protocol-defined treatment cycles in group 1, 60% (305) in group 2, and 63% (322) in group 3, although 90% (454), 89% (454), and 85% (437) completed six platinum-based chemotherapy cycles, respectively. Paclitaxel dose intensification was achieved with weekly treatment (median total paclitaxel dose 1010 mg/m2 in group 1; 1233 mg/m2 in group 2; 1274 mg/m2 in group 3). By February, 2017, 1018 (65%) patients had experienced disease progression. No significant progression-free survival increase was observed with either weekly regimen (restricted mean survival time 24·4 months [97·5% CI 23·0-26·0] in group 1, 24·9 months [24·0-25·9] in group 2, 25·3 months [23·9-26·9] in group 3; median progression-free survival 17·7 months [IQR 10·6-not reached] in group 1, 20·8 months [11·9-59·0] in group 2, 21·0 months [12·0-54·0] in group 3; log-rank p=0·35 for group 2 vs group 1; group 3 vs 1 p=0·51). Although grade 3 or 4 toxic effects increased with weekly treatment, these effects were predominantly uncomplicated. Febrile neutropenia and sensory neuropathy incidences were similar across groups. INTERPRETATION: Weekly dose-dense chemotherapy can be delivered successfully as first-line treatment for epithelial ovarian cancer but does not significantly improve progression-free survival compared with standard 3-weekly chemotherapy in predominantly European populations. FUNDING: Cancer Research UK, Medical Research Council, Health Research Board in Ireland, Irish Cancer Society, Cancer Australia.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Epitelial do Ovário/tratamento farmacológico , Neoplasias das Tubas Uterinas/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Idoso , Povo Asiático , Carboplatina/administração & dosagem , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Carcinoma Epitelial do Ovário/patologia , Quimioterapia Adjuvante , Neutropenia Febril Induzida por Quimioterapia/epidemiologia , Procedimentos Cirúrgicos de Citorredução , Neoplasias das Tubas Uterinas/patologia , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/epidemiologia , Neoplasias Peritoneais/patologia , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , População Branca
6.
Mol Cell Endocrinol ; 498: 110561, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31461666

RESUMO

Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine disorder associated with hyperandrogenism and anovulation. Although a spectrum disorder, many women with PCOS exhibit elevated luteinizing hormone (LH) pulse frequency and an elevated LH to follicle stimulating hormone ratio. This aberrant pattern of gonadotrophin signalling drives many of the downstream ovarian features of PCOS, including increased androgen synthesis, and indicates neuroendocrine impairments upstream. Decreased responsiveness to gonadal steroid hormone negative feedback in PCOS patients points toward dysfunction within the gonadotropin-releasing hormone (GnRH) neuronal network in the brain. Excessive androgen exposure during development or over pubertal onset can recapitulate the neuroendocrine pathology of PCOS in pre-clinical models, and these models have been fundamental in beginning to pick apart the specific central mechanisms involved. This mini-review will briefly describe the pathology of PCOS associated with high frequency GnRH/LH pulses and then highlight what is currently known, and yet to be discovered, about the central mechanisms involved.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/metabolismo , Sistemas Neurossecretores/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Animais , Feminino , Humanos
7.
BMC Cancer ; 19(1): 770, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382912

RESUMO

BACKGROUND: Etoposide (E) at 100 mg/m2 combined with Cisplatin (P) at 20 mg/m2 represents an induction 2-day regimen embedded in our clinical practice for patients with advanced GCT or TN at high risk of early death. We evaluated 24/7 Em-EP administration to a combined GCT-TN cohort at our Emergency Cancer Treatment Centre (ECTC) to determine its efficacy within the acute setting. METHODS: Patients who received Em-EP during a five-year interval were identified from electronic databases at Imperial College Healthcare NHS Trust. Data collected included demographics, treatment details and clinical outcome. RESULTS: Em-EP was administered in the emergency setting to 104 patients, predominantly young adults (median age 35, range 17-71). Half the cases were GCT (n = 52): 22 male (6 seminomas, 13 non-seminomas); 30 female (2 dysgerminomas, 28 non-dysgerminomas). The other 50% were treated for TN (n = 52): 45 gestational (GTN) and 7 non-gestational. Most patients received Em-EP for a new cancer diagnosis (n = 100, 96%), within 24 h (n = 93, 89%) and out-of-hours (n = 74, 70%). Indications for Em-EP included symptomatic disease (n = 66, 63%), high-burden disease, (n = 51, 49%) and organ failure requiring Intensive Care Unit support (n = 9, 9%). Neutropenic sepsis was observed in 5%. Four-week overall survival after Em-EP administration was 98%. CONCLUSIONS: Despite the potentially fatal complications encountered in the acute setting, early mortality with Em-EP is low at our ECTC. Specialist units that treat unwell patients with advanced GCT or TN should consider making Em-EP available 24/7 for emergency administration. Its efficacy within a prospective cohort and in other platinum-sensitive malignancies requires evaluation.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Cisplatino/uso terapêutico , Serviços Médicos de Emergência , Etoposídeo/uso terapêutico , Doença Trofoblástica Gestacional/tratamento farmacológico , Doença Aguda , Adolescente , Adulto , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Atenção à Saúde , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Febre/etiologia , Seguimentos , Doença Trofoblástica Gestacional/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Neutropenia/etiologia , Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Sepse/etiologia , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-29528273

RESUMO

The development of small molecules to stabilize the G-quadruplex structure has garnered significant attention for anticancer drug discovery. Herein, we report the synthesis of several 4,4'-diaminoazobenzene derivatives containing different substituent groups and their ability to bind and stabilize telomeric G-quadruplex DNA. Circular dichroism (CD) spectroscopy was performed to characterize the quadruplex topologies, measure stabilization effects, and evaluate their capabilities for conformational photoregulation. 4,4'-Diaminoazobenzene derivatives were found to moderately stabilize quadruplex structures but not affect conformational photoregulation. This work further develops the design and general understanding of the stabilization effects of small molecules with telomeric G-quadruplex DNA.


Assuntos
DNA/química , DNA/metabolismo , Quadruplex G , Telômero/genética , p-Aminoazobenzeno/análogos & derivados , Isomerismo , Processos Fotoquímicos , Temperatura , p-Aminoazobenzeno/química , p-Aminoazobenzeno/metabolismo
9.
Gynecol Oncol ; 148(2): 254-257, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29229282

RESUMO

OBJECTIVE: To quantify the risk of developing post-molar gestational trophoblastic neoplasia (pGTN) beyond the first normal human chorionic gonadotrophin (hCG) in women who have had a complete (CHM) or partial molar pregnancy (PHM) and to re-evaluate the current UK Hydatidiform mole hCG surveillance guidelines. METHODS: The Charing Cross Hospital Trophoblast Disease Centre database was screened to identify all registered cases of hydatidiform mole (HM) between 1980 and 2009. RESULTS: We identified 20,144 cases of HM, comprising 8400 CHM, 9586 PHM, and 2158 cases of unclassified hydatidiform mole (UHM). Twenty-nine cases (20 CHM, 3 PHM and 6 UHM) developed pGTN after the first normal hCG. For CHM the risk of pGTN at the point of hCG normalisation was 1 in 406, and fell rapidly in the first six months of monitoring. For PHM the risk of pGTN at the point of hCG normalisation was 1 in 3195. Women with CHM where hCG normalisation occurred beyond 56days after uterine evacuation of molar tissue were found to have a 3.8-fold higher risk of pGTN. CONCLUSIONS: Our results show that pGTN can occur after hCG normalisation following PHM but the risk is extremely low. Women with CHM have a comparatively higher risk of pGTN after hCG normalisation. Those with CHM where hCG normalises within 56days have a lower risk of pGTN. We have revised the current UK hCG surveillance protocol for PHM to a single additional confirmatory normal urine hCG measurement one month after first normalisation. The protocol for CHM remains unchanged.


Assuntos
Gonadotropina Coriônica/metabolismo , Mola Hidatiforme/terapia , Neoplasias Uterinas/terapia , Feminino , Doença Trofoblástica Gestacional/etiologia , Humanos , Mola Hidatiforme/sangue , Recidiva Local de Neoplasia/etiologia , Cuidado Pós-Natal , Guias de Prática Clínica como Assunto , Gravidez , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Neoplasias Uterinas/sangue
10.
Gen Comp Endocrinol ; 246: 194-199, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28017732

RESUMO

Epigenetic modifications in reproductive tissues have predominantly focused on pathological conditions, such as ovarian and uterine cancers. The contribution of DNA methylation and histone acetylation to the timing and control of fertility is not well described. Siberian hamsters provide an important model to investigate the relatively short-term regulation of fertility (e.g. estrous) as well as long-term timing of breeding (e.g. seasonal). Recent work has shown that DNA methyltransferase 3a (dnmt3a) expression is associated with reproductive involution. Here, the objectives were to identify the impact of photoperiod on hdac1-3 expression in hamster testicular, ovarian and uterine tissue. Then, we assessed the effect of E2P4 and estrous cycling on hdac1-3 expression in uterine tissue. Testicular expression of hdac1 was significantly reduced, whereas hdac3 increased in reproductively photoregressed male hamsters; hdac2 expression did not significantly change across photoperiod conditions. There was no significant photoperiodic effect on ovarian expression of hdac1-3. Uterine expression of hdac3 expression was greater in long day hamsters; exposure to short days significantly reduced uterine hdac2 expression. Ovariectomized hamsters administered a single bolus injection of oil were found to have elevated uterine hdac2 compared to E2P4 treated females 12h and 24h post injection. Uterine hdac1-3 expression was relatively constant across the estrous cycle. Altogether these data indicate tissue-dependent photoperiodic regulation of hdac1-3 expression and that E2P4 may inhibit uterine hdac2 over long-term breeding cycles.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/metabolismo , Histona Desacetilases/metabolismo , Ovário/metabolismo , Phodopus/metabolismo , Fotoperíodo , Animais , Western Blotting , Ritmo Circadiano/efeitos dos fármacos , Cricetinae , Estradiol/farmacologia , Estrogênios/farmacologia , Ciclo Estral/efeitos dos fármacos , Ciclo Estral/metabolismo , Feminino , Histona Desacetilase 1/genética , Histona Desacetilase 2/genética , Histona Desacetilases/genética , Masculino , Ovário/efeitos dos fármacos , Phodopus/genética , Progesterona/farmacologia , Progestinas/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reprodução/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Útero/efeitos dos fármacos , Útero/metabolismo
11.
Contemp Clin Trials ; 51: 56-64, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27777129

RESUMO

BACKGROUND: There is a considerable body of pre-clinical, epidemiological and randomised data to support the hypothesis that aspirin has the potential to be an effective adjuvant cancer therapy. METHODS: Add-Aspirin is a phase III, multi-centre, double-blind, placebo-controlled randomised trial with four parallel cohorts. Patients who have undergone potentially curative treatment for breast (n=3100), colorectal (n=2600), gastro-oesophageal (n=2100) or prostate cancer (n=2120) are registered into four tumour specific cohorts. All cohorts recruit in the United Kingdom, with the breast and gastro-oesophageal cohort also recruiting in India. Eligible participants first undertake an active run-in period where 100mg aspirin is taken daily for approximately eight weeks. Participants who are able to adhere and tolerate aspirin then undergo a double-blind randomisation and are allocated in a 1:1:1 ratio to either 100mg aspirin, 300mg aspirin or a matched placebo to be taken daily for at least five years. Those participants ≥75years old are only randomised to 100mg aspirin or placebo due to increased toxicity risk. RESULTS: The primary outcome measures are invasive disease-free survival for the breast cohort, disease-free survival for the colorectal cohort, overall survival for the gastro-oesophageal cohort, and biochemical recurrence-free survival for the prostate cohort, with a co-primary outcome of overall survival across all cohorts. Secondary outcomes include adherence, toxicity including serious haemorrhage, cardiovascular events and some cohort specific measures. CONCLUSIONS: The Add-Aspirin trial investigates whether regular aspirin use after standard therapy prevents recurrence and prolongs survival in participants with four non-metastatic common solid tumours.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Recidiva Local de Neoplasia/epidemiologia , Neoplasias/tratamento farmacológico , Taxa de Sobrevida , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Neoplasias Colorretais/tratamento farmacológico , Intervalo Livre de Doença , Método Duplo-Cego , Hipersensibilidade a Drogas/etiologia , Neoplasias Esofágicas/tratamento farmacológico , Feminino , Hemorragia Gastrointestinal/induzido quimicamente , Humanos , Índia/epidemiologia , Hemorragias Intracranianas/induzido quimicamente , Estudos Longitudinais , Degeneração Macular/induzido quimicamente , Masculino , Recidiva Local de Neoplasia/sangue , Úlcera Péptica/induzido quimicamente , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Zumbido/induzido quimicamente , Reino Unido/epidemiologia
12.
J Reprod Immunol ; 117: 10-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27348190

RESUMO

Cationic host defence peptides (CHDP; also known as antimicrobial peptides) are key components of the immune response in the female reproductive tract. The role of the placental trophoblast in ovine host defence remains poorly understood. This study characterises expression of genes for cathelicidin and defensin peptides in primary ovine placental tissues, the ovine trophoblast cell line (AH-1) and in response to the TLR-4 ligand LPS, the abortifacient organism Waddlia chondrophila and 1α,25-dihydroxyvitamin D3. Using RT-PCR, expression of the CHDP SMAP-29, sBD-1 and sBD-2 was assessed in the AH-1 cell line in response to LPS, 1α,25-dihydroxyvitamin D3 exposure (a known stimulator of cathelicidin gene expression), or W. chondrophila infection. Expression of cathelicidin in the trophoblast compartment of the ovine placenta and in the ovine trophoblast cell line (AH-1) was also established. AH-1 cells did not upregulate expression of CHDP in response to LPS, but sBD-1 and sBD-2 expression was significantly increased in response to W. chondrophila infection. SMAP-29 expression was not altered by in vitro exposure to 1α,25-dihydroxyvitamin D3. This study demonstrates that the ovine trophoblast expresses cathelicidins, but does not upregulate expression of CHDP in response to LPS. Ovine trophoblasts are shown to differentially regulate expression of CHDP and lack a demonstrable vitamin D-mediated cathelicidin response.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Chlamydiales/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Placenta/fisiologia , Doenças dos Ovinos/imunologia , Ovinos/imunologia , Trofoblastos/imunologia , 24,25-Di-Hidroxivitamina D 3/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Catelicidinas/genética , Catelicidinas/metabolismo , Bovinos , Linhagem Celular , Defensinas/genética , Defensinas/metabolismo , Feminino , Regulação da Expressão Gênica , Infecções por Bactérias Gram-Negativas/veterinária , Imunidade Inata , Lipopolissacarídeos/imunologia , Gravidez , Trofoblastos/microbiologia , Trofoblastos/patologia
13.
Curr Colorectal Cancer Rep ; 12: 27-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27069437

RESUMO

There is now a considerable body of data supporting the hypothesis that aspirin could be effective in the prevention and treatment of colorectal cancer, and a number of phase III randomised controlled trials designed to evaluate the role of aspirin in the treatment of colorectal cancer are ongoing. Although generally well tolerated, aspirin can have adverse effects, including dyspepsia and, infrequently, bleeding. To ensure a favourable balance of benefits and risks from aspirin, a more personalised assessment of the advantages and disadvantages is required. Emerging data suggest that tumour PIK3CA mutation status, expression of cyclo-oxygenase-2 and human leukocyte antigen class I, along with certain germline polymorphisms, might all help to identify individuals who stand to gain most. We review both the underpinning evidence and current data, on clinical, molecular and genetic biomarkers for aspirin use in the prevention and treatment of colorectal cancer, and discuss the opportunities for further biomarker research provided by ongoing trials.

14.
J Med Case Rep ; 9: 285, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26667003

RESUMO

INTRODUCTION: Erythema nodosum is often associated with a distressing symptomatology, including painful subcutaneous nodules, polyarthropathy, and significant fatigue. Whilst it is a well-documented side-effect of estrogen therapy in females, we describe what we believe to be the first report in the literature of erythema nodosum as a result of estrogen therapy in a male. CASE PRESENTATION: A 64-year-old Afro-Caribbean man with locally advanced carcinoma of the prostate agreed to participate in a randomized controlled trial comparing estrogen patches with luteinizing hormone-releasing hormone analogs to achieve androgen deprivation, and was allocated to the group receiving estrogen patches. One month later he presented with tender lesions on his shins and painful swelling of his ankles, wrists, and left shoulder. This was followed by progressive severe fatigue that required hospital admission, where he was diagnosed with erythema nodosum by a rheumatologist. Two months after discontinuing the estrogen patches the erythema nodosum, and associated symptoms, had fully resolved, and to date he remains well with no further recurrence. CONCLUSION: Trial results may establish transdermal estrogen as an alternative to luteinizing hormone-releasing hormone analogs in the management of prostate cancer, and has already been established as a therapy for male to female transsexuals. It is essential to record the toxicity profile of transdermal estrogen in men to ensure accurate safety information. This case report highlights a previously undocumented toxicity of estrogen therapy in men, of which oncologists, urologists, and endocrinologists need to be aware. Rheumatologists and dermatologists should add estrogen therapy to their differential diagnosis of men presenting with erythema nodosum.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/efeitos adversos , Eritema Nodoso/induzido quimicamente , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Neoplasias da Próstata/tratamento farmacológico , Administração Cutânea , Eritema Nodoso/patologia , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Fadiga/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Falha de Tratamento
15.
PLoS One ; 9(7): e102386, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25010668

RESUMO

BACKGROUND: Waddlia chondrophila (W. chondrophila) is an emerging abortifacient organism which has been identified in the placentae of humans and cattle. The organism is a member of the order Chlamydiales, and shares many similarities at the genome level and in growth studies with other well-characterised zoonotic chlamydial abortifacients, such as Chlamydia abortus (C. abortus). This study investigates the growth of the organism and its effects upon pro-inflammatory cytokine expression in a ruminant placental cell line which we have previously utilised in a model of C. abortus pathogenicity. METHODOLOGY/PRINCIPAL FINDINGS: Using qPCR, fluorescent immunocytochemistry and electron microscopy, we characterised the infection and growth of W. chondrophila within the ovine trophoblast AH-1 cell line. Inclusions were visible from 6 h post-infection (p.i.) and exponential growth of the organism could be observed over a 60 h time-course, with significant levels of host cell lysis being observed only after 36 h p.i. Expression of CXCL8, TNF-α, IL-1α and IL-1ß were determined 24 h p.i. A statistically significant response in the expression of CXCL8, TNF-α and IL-1ß could be observed following active infection with W. chondrophila. However a significant increase in IL-1ß expression was also observed following the exposure of cells to UV-killed organisms, indicating the stimulation of multiple innate recognition pathways. CONCLUSIONS/SIGNIFICANCE: W. chondrophila infects and grows in the ruminant trophoblast AH-1 cell line exhibiting a complete chlamydial replicative cycle. Infection of the trophoblasts resulted in the expression of pro-inflammatory cytokines in a dose-dependent manner similar to that observed with C. abortus in previous studies, suggesting similarities in the pathogenesis of infection between the two organisms.


Assuntos
Chlamydia/patogenicidade , Placenta/microbiologia , Trofoblastos/microbiologia , Animais , Bovinos , Chlamydia/genética , Feminino , Expressão Gênica , Interleucina-1beta/biossíntese , Interleucina-8/biossíntese , Microscopia Eletrônica , Placenta/patologia , Gravidez , Ovinos/microbiologia , Carneiro Doméstico/microbiologia , Trofoblastos/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
16.
Exp Neurol ; 261: 386-95, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24818543

RESUMO

Some psychiatric diseases in children and young adults are thought to originate from adverse exposures during foetal life, including hypoxia and hypoxia/reoxygenation. The mechanism is not understood. Several authors have emphasised that the placenta is likely to play an important role as the key interface between mother and foetus. Here we have explored whether a first trimester human placenta or model barrier of primary human cytotrophoblasts might secrete factors, in response to hypoxia or hypoxia/reoxygenation, that could damage neurones. We find that the secretions in conditioned media caused an increase of [Ca(2+)]i and mitochondrial free radicals and a decrease of dendritic lengths, branching complexity, spine density and synaptic activity in dissociated neurones from embryonic rat cerebral cortex. There was altered staining of glutamate and GABA receptors. We identify glutamate as an active factor within the conditioned media and demonstrate a specific release of glutamate from the placenta/cytotrophoblast barriers invitro after hypoxia or hypoxia/reoxygenation. Injection of conditioned media into developing brains of P4 rats reduced the numerical density of parvalbumin-containing neurones in cortex, hippocampus and reticular nucleus, reduced immunostaining of glutamate receptors and altered cellular turnover. These results show that the placenta is able to release factors, in response to altered oxygen, that can damage developing neurones under experimental conditions.


Assuntos
Encéfalo , Meios de Cultivo Condicionados/efeitos adversos , Hipóxia , Neurônios/efeitos dos fármacos , Oxigênio/farmacologia , Placenta/química , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Hipóxia Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Meios de Cultivo Condicionados/química , Dendritos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Feminino , Feto , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Hipóxia/tratamento farmacológico , Hipóxia/patologia , Hipóxia/fisiopatologia , Potenciais da Membrana/efeitos dos fármacos , Neurônios/citologia , Neurônios/fisiologia , Placenta/citologia , Gravidez , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Cultura de Tecidos
18.
Exerc Sport Sci Rev ; 36(4): 187-92, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18815487

RESUMO

In mice, targeted deletion of the basic helix-loop-helix transcription factor, nescient helix-loop-helix 2 (Nhlh2), leads to adult-onset obesity and reduced physical activity. We propose the novel hypothesis that transcriptional activity by Nhlh2 (NHLH2 in humans) controls either the ability or the motivation for exercise.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Atividade Motora/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Deleção de Genes , Ligação Genética , Humanos , Camundongos , Camundongos Knockout , Motivação , Obesidade/genética , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Physiol Behav ; 95(1-2): 168-75, 2008 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-18619628

RESUMO

The Tub gene was originally identified as a spontaneous mutation in C57Bl/6J mice, and associated with adult-onset obesity (Tub MUT mice). Although the original Tub MUT mouse was identified over 15 years ago, there have been few reports on the animal's food intake, body fat percentage or energy expenditure. In this study, we report food intake, body weight from 5-20 weeks, body fat, body temperature and three different measures of physical activity behavior. Tub MUT mice display reduced food intake, uncharacteristic of many obese mouse models, and reduced voluntary wheel running with normal home cage ambulatory behavior. We conclude that motivation for food and exercise is an underlying defect in TUB MUT mice.


Assuntos
Hiperfagia/fisiopatologia , Obesidade/genética , Obesidade/fisiopatologia , Proteínas/genética , Proteínas Adaptadoras de Transdução de Sinal , Fatores Etários , Análise de Variância , Animais , Comportamento Animal , Temperatura Corporal/genética , Peso Corporal/genética , Ingestão de Alimentos/genética , Gorduras/metabolismo , Comportamento Alimentar/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Atividade Motora/genética , Teste de Desempenho do Rota-Rod/métodos
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