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1.
Crit Care ; 28(1): 2, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166968

RESUMO

Surface electromyography (sEMG) can be used to measure the electrical activity of the respiratory muscles. The possible applications of sEMG span from patients suffering from acute respiratory failure to patients receiving chronic home mechanical ventilation, to evaluate muscle function, titrate ventilatory support and guide treatment. However, sEMG is mainly used as a monitoring tool for research and its use in clinical practice is still limited-in part due to a lack of standardization and transparent reporting. During this round table meeting, recommendations on data acquisition, processing, interpretation, and potential clinical applications of respiratory sEMG were discussed. This paper informs the clinical researcher interested in respiratory muscle monitoring about the current state of the art on sEMG, knowledge gaps and potential future applications for patients with respiratory failure.


Assuntos
Músculo Esquelético , Músculos Respiratórios , Humanos , Eletromiografia , Músculos Respiratórios/fisiologia , Músculo Esquelético/fisiologia
2.
ISME J ; 16(4): 1055-1064, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34819612

RESUMO

The filamentous diazotrophic cyanobacterium Trichodesmium is responsible for a significant fraction of marine di-nitrogen (N2) fixation. Growth and distribution of Trichodesmium and other diazotrophs in the vast oligotrophic subtropical gyres is influenced by iron (Fe) and phosphorus (P) availability, while reciprocally influencing the biogeochemistry of these nutrients. Here we use observations across natural inverse gradients in Fe and P in the North Atlantic subtropical gyre (NASG) to demonstrate how Trichodesmium acclimates in situ to resource availability. Transcriptomic analysis identified progressive upregulation of known iron-stress biomarker genes with decreasing Fe availability, and progressive upregulation of genes involved in the acquisition of diverse P sources with decreasing P availability, while genes involved in N2 fixation were upregulated at the intersection under moderate Fe and P availability. Enhanced N2 fixation within the Fe and P co-stressed transition region was also associated with a distinct, consistent metabolic profile, including the expression of alternative photosynthetic pathways that potentially facilitate ATP generation required for N2 fixation with reduced net oxygen production. The observed response of Trichodesmium to availability of both Fe and P supports suggestions that these biogeochemically significant organisms employ unique molecular, and thus physiological responses as adaptations to specifically exploit the Fe and P co-limited niche they construct.


Assuntos
Cianobactérias , Trichodesmium , Cianobactérias/genética , Cianobactérias/metabolismo , Ferro/metabolismo , Nitrogênio/metabolismo , Fixação de Nitrogênio/genética , Trichodesmium/genética , Trichodesmium/metabolismo
3.
Res Involv Engagem ; 7(1): 81, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789334

RESUMO

BACKGROUND: ReIMAGINE aims to improve the current prostate specific antigen (PSA)/biopsy risk stratification for prostate cancer (PCa) and develop a new image-based method (with biomarkers) for diagnosing high/low risk PCa in men. ReIMAGINE's varied patient and public involvement (PPI) and engagement (PE) strategy maximises the impact of its scientific output by informing and shaping the different stages of research. AIMS: Through including the voice of patients and the public, the ReIMAGINE Consortium aims to translate these different perspectives into the design and implementation process. This will improve the overall quality of the research by: reflecting the needs and priorities of patients and the public, ensuring methods and procedures are feasible and appropriate ensuring information is relevant and accessible to those being recruited to the study identifying dissemination channels relevant to patients/the public and developing outputs that are accessible to a lay audience With support from our patient/user groups, the ReIMAGINE Consortium aims to improve our ability to derive prognostic information and allocate men to the most appropriate and effective therapies, using a novel image-based risk stratification with investigation of non-imaging biomarkers. FINDINGS: We have been working with patients and the public from initiation of the project to ensure that the research is relevant to men and their families. Our PPI Sub-Committee, led by a PCa patient, has been involved in our dissemination strategy, outreach activities, and study design recommendations. For example, the sub-committee have developed a variety of informative videos relevant and accessible to those being recruited, and organised multiple online research engagement events that are accessible to a lay audience. As quoted by one of the study participants, "the more we present the benefits and opportunities to patients and the public, the more research commitment we obtain, and the sooner critical clinical questions such as PCa diagnostics will be addressed".


One in eight men will be diagnosed with prostate cancer (PCa). Most will not die of it, but our ability to identify those men whose cancer poses the greatest threat to life has, thus far, been poor. Some men are diagnosed with small cancers which will never cause them a problem, some will have treatment which is unnecessary, others will have their cancers missed, and others will be misclassified as either having low risk cancer and will therefore miss out on the appropriate treatment, or told their cancer is high risk and have unnecessary treatment. Nowhere else in modern medicine are these errors of over-diagnosis, over-treatment, missed-diagnoses, and poor risk-stratification more common. The ReIMAGINE Consortium has been developed to undertake discoveries that will correct these four key errors in the PCa diagnostic pathway. We will investigate how to best identify which men have, or will develop, aggressive prostate cancer using imaging combined with advanced biomarker analyses of blood and urine (i.e., OMICs technologies such as whole genome sequencing, targeted sequencing (e.g.: = , methylation). We will achieve this by building on established partnerships between patients, advocacy organisations, clinicians, imaging experts, molecular biologists, methodologists, and a broad range of industrial partners.The Patient and Public Involvement (PPI) sub-committee is an integral part of the study workflow, contributing to study design and recruitment, results analysis, and dissemination. The committee, led by a funded PPI co-ordinator and a patient chair, have given invaluable insight into the study modifications due to COVID-19 restrictions.

4.
Chem Commun (Camb) ; 57(88): 11705-11708, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34693408

RESUMO

A series of iridium hydride complexes featuring dihydrogen bonding are presented and shown to undergo rapid H+/H- exchange (1240 s-1 at 25 °C). We demonstrate that the H+/H- exchange rate can be modified by post-synthetic modification at a remote site using BH3, Zn(C6F5)2, and [Me3O][BF4]. This route provides a complementary strategy to traditional methods that rely on pre-metalation modifications to a metal's primary sphere.

5.
Prog Urol ; 30(16): 986-999, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33008718

RESUMO

BACKGROUND: Many guidelines now recommend multiparametric MRI (mpMRI) prior to an initial or repeat prostate biopsy. However, clinical decision making for men with a non-suspicious mpMRI (Likert or PIRADS score 1-2) varies. OBJECTIVES: To review the most recent literature to answer three questions. (1) Should we consider systematic biopsy if mpMRI is not suspicious? (2) Are there additional predictive factors that can help decide which patient should have a biopsy? (3) Can the low visibility of some cancers be explained and what are the implications? SOURCES: A narrative review was performed in Medline databases using two searches with the terms "MRI" and "prostate cancer" and ("diagnosis" or "biopsy") and ("non-suspicious" or "negative" or "invisible"); "prostate cancer MRI visible". References of the selected articles were screened for additional articles. STUDY SELECTION: Studies published in the last 5 years in English language were assessed for eligibility and selected if data was available to answer one of the three study questions. RESULTS: Considering clinically significant cancer as ISUP grade≥2, the negative predictive value (NPV) of mpMRI in various settings and populations ranges from 76% to 99%, depending on cancer prevalence and the type of confirmatory reference test used. NPV is higher among patients with prior negative biopsy (88-96%), and lower for active surveillance patients (85-90%). The PSA density (PSAd) with a threshold of PSAd<0.15ng/ml/ml was the most studied and relevant predictive factor used in combination with mpMRI to rule out clinically significant cancer. Finally, mpMRI-invisible tumours appear to differ from a histopathological and genetic point of view, conferring clinical advantage to invisibility. LIMITATIONS: Most published data come from expert centres and results may not be reproducible in all settings. CONCLUSION: mpMRI has high diagnostic accuracy and in cases of negative mpMRI, PSA density can be used to determine which patient should have a biopsy. Growing knowledge of the mechanisms and genetics underlying MRI visibility will help develop more accurate risk calculators and biomarkers.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Biópsia , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
6.
Sci Rep ; 10(1): 8212, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32427904

RESUMO

Bulk chemotherapy and drug release strategies for cancer treatment have been associated with lack of specificity and high drug concentrations that often result in toxic side effects. This work presents the results of an experimental study of cancer drugs (prodigiosin or paclitaxel) conjugated to Luteinizing Hormone-Releasing Hormone (LHRH) for the specific targeting and treatment of triple negative breast cancer (TNBC). Injections of LHRH-conjugated drugs (LHRH-prodigiosin or LHRH-paclitaxel) into groups of 4-week-old athymic female nude mice (induced with subcutaneous triple negative xenograft breast tumors) were found to specifically target, eliminate or shrink tumors at early, mid and late stages without any apparent cytotoxicity, as revealed by in vivo toxicity and ex vivo histopathological tests. Our results show that overexpressed LHRH receptors serve as binding sites on the breast cancer cells/tumor and the LHRH-conjugated drugs inhibited the growth of breast cells/tumor in in vitro and in vivo experiments. The inhibitions are attributed to the respective adhesive interactions between LHRH molecular recognition units on the prodigiosin (PGS) and paclitaxel (PTX) drugs and overexpressed LHRH receptors on the breast cancer cells and tumors. The implications of the results are discussed for the development of ligand-conjugated drugs for the specific targeting and treatment of TNBC.


Assuntos
Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Hormônio Liberador de Gonadotropina/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , RNA Interferente Pequeno/genética , Receptores LHRH/genética , Receptores LHRH/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Cancer Treat Rev ; 58: 14-21, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28609648

RESUMO

Although the incidence of prostate cancer is rising due to PSA screening and increased life expectancy, the metastatic potential of low-grade, organ-confined disease remains low. An increasing number of studies suggest that radical treatment in such cases confers little or no survival benefit at a significant cost to morbidity. Active surveillance is a promising management approach of such low-risk cancers: eligible patients are selected based on clinical and pathological findings at diagnosis and are regularly monitored with digital rectal examinations, PSA testing and biopsies. Treatment, however, is deferred until and unless there is evidence of disease progression. This is a key difference from watchful waiting, where treatment is avoided until and unless there are symptoms. The purpose of this work is to review the rationale and evidence behind active surveillance and to offer an overview of current active surveillance strategies and outcomes.


Assuntos
Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Conduta Expectante , Exame Retal Digital , Humanos , Imageamento por Ressonância Magnética , Masculino , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Fatores de Risco
8.
Nat Commun ; 8: 15465, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28524880

RESUMO

In certain regions of the predominantly nitrogen limited ocean, microbes can become co-limited by phosphorus. Within such regions, a proportion of the dissolved organic phosphorus pool can be accessed by microbes employing a variety of alkaline phosphatase (APase) enzymes. In contrast to the PhoA family of APases that utilize zinc as a cofactor, the recent discovery of iron as a cofactor in the more widespread PhoX and PhoD implies the potential for a biochemically dependant interplay between oceanic zinc, iron and phosphorus cycles. Here we demonstrate enhanced natural community APase activity following iron amendment within the low zinc and moderately low iron Western North Atlantic. In contrast we find no evidence for trace metal limitation of APase activity beneath the Saharan dust plume in the Eastern Atlantic. Such intermittent iron limitation of microbial phosphorus acquisition provides an additional facet in the argument for iron controlling the coupling between oceanic nitrogen and phosphorus cycles.


Assuntos
Cianobactérias/metabolismo , Ferro/química , Nitrogênio/química , Fósforo/química , África do Norte , Fosfatase Alcalina/metabolismo , Oceano Atlântico , Clorofila/química , Clorofila A , Citometria de Fluxo , Geografia , Fixação de Nitrogênio , Fotossíntese , Água do Mar , Clima Tropical , Microbiologia da Água
9.
Front Microbiol ; 8: 2683, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29387046

RESUMO

The marine cyanobacterium Trichodesmium sp. accounts for approximately half of the annual 'new' nitrogen introduced to the global ocean but its biogeography and activity is often limited by the availability of iron (Fe). A major source of Fe to the open ocean is Aeolian dust deposition in which Fe is largely comprised of particles with reduced bioavailability over soluble forms of Fe. We report that Trichodesmium erythraeum IMS101 has improved growth rate and photosynthetic physiology and down-regulates Fe-stress biomarker genes when cells are grown in the direct vicinity of, rather than physically separated from, Saharan dust particles as the sole source of Fe. These findings suggest that availability of non-soluble forms of dust-associated Fe may depend on cell contact. Transcriptomic analysis further reveals unique profiles of gene expression in all tested conditions, implying that Trichodesmium has distinct molecular signatures related to acquisition of Fe from different sources. Trichodesmium thus appears to be capable of employing specific mechanisms to access Fe from complex sources in oceanic systems, helping to explain its role as a key microbe in global biogeochemical cycles.

10.
Clin Exp Allergy ; 46(12): 1549-1563, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27513438

RESUMO

BACKGROUND: Rhinovirus (RV) infection in asthma induces varying degrees of airway inflammation (e.g. neutrophils), but the underlying mechanisms remain unclear. OBJECTIVE: The major goal was to determine the role of genetic variation [e.g. single nucleotide polymorphisms (SNPs)] of Toll-interacting protein (Tollip) in airway epithelial responses to RV in a type 2 cytokine milieu. METHODS: DNA from blood of asthmatic and normal subjects was genotyped for Tollip SNP rs5743899 AA, AG and GG genotypes. Human tracheobronchial epithelial (HTBE) cells from donors without lung disease were cultured to determine pro-inflammatory and antiviral responses to IL-13 and RV16. Tollip knockout and wild-type mice were challenged with house dust mite (HDM) and infected with RV1B to determine lung inflammation and antiviral response. RESULTS: Asthmatic subjects carrying the AG or GG genotype (AG/GG) compared with the AA genotype demonstrated greater airflow limitation. HTBE cells with AG/GG expressed less Tollip. Upon IL-13 and RV16 treatment, cells with AG/GG (vs. AA) produced more IL-8 and expressed less antiviral genes, which was coupled with increased NF-κB activity and decreased expression of LC3, a hallmark of the autophagic pathway. Tollip co-localized and interacted with LC3. Inhibition of autophagy decreased antiviral genes in IL-13- and RV16-treated cells. Upon HDM and RV1B, Tollip knockout (vs. wild-type) mice demonstrated higher levels of lung neutrophilic inflammation and viral load, but lower levels of antiviral gene expression. CONCLUSIONS AND CLINICAL RELEVANCE: Our data suggest that Tollip SNP rs5743899 may predict varying airway response to RV infection in asthma.


Assuntos
Alelos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Infecções por Picornaviridae/genética , Infecções por Picornaviridae/virologia , Polimorfismo de Nucleotídeo Único , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , Rhinovirus/imunologia , Adulto , Idoso , Animais , Autofagia , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Genótipo , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Infecções por Picornaviridae/imunologia , Infecções por Picornaviridae/patologia , Interferência de RNA , Testes de Função Respiratória , Carga Viral
11.
Prostate Cancer Prostatic Dis ; 19(3): 311-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27431499

RESUMO

BACKGROUND: Treatment options for radio-recurrent prostate cancer are either androgen-deprivation therapy or salvage prostatectomy. Whole-gland high-intensity focussed ultrasound (HIFU) might have a role in this setting. METHODS: An independent HIFU registry collated consecutive cases of HIFU. Between 2005 and 2012, we identified 50 men who underwent whole-gland HIFU following histological confirmation of localised disease following prior external beam radiotherapy (2005-2012). No upper threshold was applied for risk category, PSA or Gleason grade either at presentation or at the time of failure. Progression was defined as a composite with biochemical failure (Phoenix criteria (PSA>nadir+2 ng ml(-1))), start of systemic therapies or metastases. RESULTS: Median age (interquartile range (IQR)), pretreatment PSA (IQR) and Gleason score (range) were 68 years (64-72), 5.9 ng ml(-1) (2.2-11.3) and 7 (6-9), respectively. Median follow-up was 64 months (49-84). In all, 24/50 (48%) avoided androgen-deprivation therapies. Also, a total of 28/50 (56%) achieved a PSA nadir <0.5 ng ml(-1), 15/50 (30%) had a nadir ⩾0.5 ng ml(-1) and 7/50 (14%) did not nadir (PSA non-responders). Actuarial 1, 3 and 5-year progression-free survival (PFS) was 72, 40 and 31%, respectively. Actuarial 1, 3 and 5-year overall survival (OS) was 100, 94 and 87%, respectively. When comparing patients with PSA nadir <0.5 ng ml(-1), nadir ⩾0.5 and non-responders, a statistically significant difference in PFS was seen (P<0.0001). Three-year PFS in each group was 57, 20 and 0%, respectively. Five-year OS was 96, 100 and 38%, respectively. Early in the learning curve, between 2005 and 2007, 3/50 (6%) developed a fistula. Intervention for bladder outlet obstruction was needed in 27/50 (54%). Patient-reported outcome measure questionnaires showed incontinence (any pad-use) as 8/26 (31%). CONCLUSIONS: In our series of high-risk patients, in whom 30-50% may have micro-metastases, disease control rates were promising in PSA responders, however, with significant morbidity. Additionally, post-HIFU PSA nadir appears to be an important predictor for both progression and survival. Further research on focal salvage ablation in order to reduce toxicity while retaining disease control rates is required.


Assuntos
Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Idoso , Terapia Combinada , Progressão da Doença , Seguimentos , Ablação por Ultrassom Focalizado de Alta Intensidade , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Gradação de Tumores , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Radioterapia Adjuvante/métodos , Análise de Sobrevida , Resultado do Tratamento
12.
Urologe A ; 54(2): 202-9, 2015 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-25690574

RESUMO

Focal therapy is a treatment strategy for men with localized prostate cancer that may serve as an alternative option to radical therapy. A number of minimally invasive ablative technologies are available to deliver treatment, and the energies most commonly used include high-intensity focused ultrasound and cryotherapy. The benefit of a tissue-preserving approach is the limitation of damage to key structures such as the neurovascular bundles, external urinary sphincter, rectal mucosa and bladder neck. This in turn minimizes side effects typically associated with radical therapies whilst also aiming to maintain oncological control. Over 30 single-centre studies of focal therapy have been published to date reporting excellent continence rates, good potency rates and acceptable short-term oncological outcomes. However, there are a number of controversial aspects associated with focal therapy including the index lesion hypothesis, patient selection criteria, assessment of treatment effect and the lack of medium- and long-term oncological outcomes. In the process of the adoption of new technology, there is a limited window of opportunity to provide this evidence in well-designed prospective trials. Men should be allowed to benefit from the potential advantages of this novel treatment whilst under close surveillance. An English version of this article is available under dx.doi.org/10.1007/s00120-014-3734-7.


Assuntos
Criocirurgia/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Tratamentos com Preservação do Órgão/métodos , Neoplasias da Próstata/cirurgia , Medicina Baseada em Evidências , Alemanha , Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Resultado do Tratamento
13.
Schizophr Res ; 161(2-3): 202-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25480359

RESUMO

BACKGROUND: Superior temporal cortices include brain regions dedicated to auditory processing and several lines of evidence suggest structural and functional abnormalities in both schizophrenia and bipolar disorder within this brain region. However, possible glutamatergic dysfunction within this region has not been investigated in adult patients. METHODS: Thirty patients with schizophrenia (38.67±12.46years of age), 28 euthymic patients with bipolar I disorder (35.32±9.12years of age), and 30 age-, gender- and education-matched healthy controls were enrolled. Proton magnetic resonance spectroscopy data were acquired using a 3.0T Siemens MAGNETOM TIM Trio MR system and single voxel Point REsolved Spectroscopy Sequence (PRESS) in order to quantify brain metabolites within the left and right Heschl's gyrus and planum temporale of superior temporal cortices. RESULTS: There were significant abnormalities in glutamate (Glu) (F(2,78)=8.52, p<0.0001), N-acetyl aspartate (tNAA) (F(2,81)=5.73, p=0.005), creatine (tCr) (F(2,83)=5.91, p=0.004) and inositol (Ins) (F(2,82)=8.49, p<0.0001) concentrations in the left superior temporal cortex. In general, metabolite levels were lower for bipolar disorder patients when compared to healthy participants. Moreover, patients with bipolar disorder exhibited significantly lower tCr and Ins concentrations when compared to schizophrenia patients. In addition, we have found significant correlations between the superior temporal cortex metabolites and clinical measures. CONCLUSION: As the left auditory cortices are associated with language and speech, left hemisphere specific abnormalities may have clinical significance. Our findings are suggestive of shared glutamatergic abnormalities in schizophrenia and bipolar disorder.


Assuntos
Ácido Aspártico/análogos & derivados , Córtex Auditivo/metabolismo , Transtorno Bipolar/patologia , Creatina/metabolismo , Esquizofrenia/patologia , Lobo Temporal/metabolismo , Adulto , Análise de Variância , Ácido Aspártico/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Espectroscopia de Prótons por Ressonância Magnética , Adulto Jovem
14.
Int Urogynecol J ; 25(1): 143-4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23749239

RESUMO

We report the inadvertent insertion of a urinary catheter into the upper moiety ureter of a duplex kidney, in a full-term pregnant woman prior to an emergency caesarean section. The patient complained of severe pain during inflation of the catheter balloon. All measures to deflate the balloon and remove the catheter failed. Retrograde ureteric contrast examination showed the placement of the catheter in the proximal part the right upper moiety ureter of a duplex ureter. The catheter was removed with ureteroscopic forceps. We concluded that congenital variation of the urinary tract can complicate a simple catheterisation.


Assuntos
Ureter/anormalidades , Cateterismo Urinário/efeitos adversos , Adulto , Feminino , Humanos , Gravidez
16.
Contemp Clin Trials ; 34(1): 80-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23085153

RESUMO

OBJECTIVE: To evaluate the percentage change in volume of prostate cancer, as assessed by T2-weighted MRI, following exposure to dutasteride (Avodart) 0.5mg daily for six months. PATIENTS AND METHODS: MRI in Primary Prostate cancer after Exposure to Dutasteride (MAPPED) is a double-blind, placebo-controlled trial, supported by GlaxoSmithKline (GSK). Men with prostate cancer suitable for active surveillance (low-intermediate risk prostate cancer on biopsy), and a visible lesion on T2-weighted MRI of at least 0.2 cc, were eligible for consideration. Forty-two men were randomised to 6 months of daily dutasteride 0.5mg or placebo. Multi-parametric MRI (mpMRI) scans were performed at baseline, 3 and 6 months. The percentage changes in cancer volume over time will be compared between the dutasteride and placebo groups. Planned analyses will examine the association between tumour volume and characteristics (perfusion and contrast washout) as seen on mpMRI, HistoScan ultrasound and biopsy histopathology in both groups. DISCUSSION: MAPPED is the first randomised controlled trial to use mpMRI to look at the effect of dutasteride on the volume of prostate cancer. If dutasteride is shown to reduce the volume of prostate cancer, it might be considered as an adjunct for men on active surveillance. Analysis of the placebo arm will allow us to comment on the short-term natural variability of the MR appearance in men who are not receiving any treatment. CONCLUSION: MAPPED will evaluate the short-term effect of dutasteride on prostate cancer volume, as assessed by mpMRI, in men undergoing active surveillance for low or intermediate risk prostate cancer. The study completed recruitment in January 2012.


Assuntos
Azasteroides/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Inibidores de 5-alfa Redutase/administração & dosagem , Adulto , Biópsia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dutasterida , Seguimentos , Humanos , Masculino , Tamanho do Órgão , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico , Fatores de Tempo , Resultado do Tratamento
17.
World J Urol ; 28(5): 571-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20454966

RESUMO

Although in early stages of clinical development, photodynamic therapy (PDT) shows promise in delivering focal treatment of both primary and post-radiotherapy prostate cancer. This article will review the mechanism of action of PDT, previous research using PDT for treating prostate cancer including the development of newer vascular-acting photosensitizers, and the potential advantages and disadvantages of PDT in delivering focal therapy.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Éter de Diematoporfirina/uso terapêutico , Humanos , Masculino , Mesoporfirinas/uso terapêutico , Metaloporfirinas/uso terapêutico , Fotoquimioterapia/efeitos adversos , Resultado do Tratamento
18.
Eur Respir J ; 34(2): 324-331, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19357152

RESUMO

Alveolar elastic fibres are key targets of proteases during the pathogenesis of chronic obstructive pulmonary disease (COPD). In the current study, we hypothesised that a response to injury leads to enhanced alveolar elastin gene expression in very severe COPD. Lung samples obtained from 43 patients, including 11 with very severe COPD (stage 4), 10 donors, 10 with moderate/severe COPD (stage 2-3) and 12 non-COPD subjects, were analysed for elastin mRNA expression by real-time RT-PCR and in situ hybridisation. Alveolar elastic fibres were visualised using Hart's staining of sections of frozen inflated lungs obtained from 11 COPD stage 4 patients and three donor lungs. Compared with donors, non-COPD and stage 2-3 COPD, elastin mRNA expression was significantly increased in very severe COPD lungs (12-fold change), and localised in situ hybridisation induced elastin expression to alveolar walls. Compared with donors, alveolar elastic fibres also comprised a greater volume fraction of total lung tissue in very severe COPD lungs (p<0.01), but elastic fibre content was not increased per lung volume, and desmosine content was not increased. The present study demonstrates enhanced alveolar elastin expression in very severe COPD. The efficiency of this potential repair mechanism and its regulation remain to be demonstrated.


Assuntos
Elastina/biossíntese , Regulação da Expressão Gênica , Alvéolos Pulmonares/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Adulto , Idoso , Feminino , Humanos , Hibridização In Situ , Transplante de Pulmão , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fumar
19.
Science ; 320(5878): 893-7, 2008 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-18487184

RESUMO

Increasing quantities of atmospheric anthropogenic fixed nitrogen entering the open ocean could account for up to about a third of the ocean's external (nonrecycled) nitrogen supply and up to approximately 3% of the annual new marine biological production, approximately 0.3 petagram of carbon per year. This input could account for the production of up to approximately 1.6 teragrams of nitrous oxide (N2O) per year. Although approximately 10% of the ocean's drawdown of atmospheric anthropogenic carbon dioxide may result from this atmospheric nitrogen fertilization, leading to a decrease in radiative forcing, up to about two-thirds of this amount may be offset by the increase in N2O emissions. The effects of increasing atmospheric nitrogen deposition are expected to continue to grow in the future.


Assuntos
Atmosfera , Atividades Humanas , Nitrogênio , Espécies Reativas de Nitrogênio , Água do Mar , Carbono , Dióxido de Carbono/metabolismo , Ecossistema , Humanos , Nitrogênio/metabolismo , Fixação de Nitrogênio , Oceanos e Mares , Espécies Reativas de Nitrogênio/metabolismo
20.
Lasers Surg Med ; 38(5): 356-63, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16392142

RESUMO

BACKGROUND AND OBJECTIVES: Prostate cancer is increasing in incidence, but current treatments including surgery and radiotherapy have significant side effects. This pilot study was designed to assess the potential of photodynamic therapy (PDT) using meso tetra hydroxy phenyl chlorin (mTHPC) for organ confined prostate cancer. STUDY DESIGN/PATIENTS AND METHODS: Six men with organ confined prostate cancer were photosensitised with mTHPC (0.15 mg/kg). Between 2 and 5 days later, red light (652 nm) was delivered to areas of biopsy proven cancer via fibres inserted through transperineal needles (50-100 J per site). RESULTS: After 8 of 10 PDT sessions, the prostate specific antigen (PSA) fell by up to 67%. Early MRI scans showed oedema and patchy necrosis, which resolved over 2 months. Biopsies of treated areas revealed necrosis and fibrosis at 1-2 months. CONCLUSIONS: PDT for primary prostate cancer appears safe and can reduce PSA levels. As this was a phase I study, no attempt was made to treat the whole prostate; this or targeted tumour ablation could be attempted in a phase II study with an increased number of fibres. This technique merits further investigation in early prostate cancer.


Assuntos
Mesoporfirinas/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Biópsia , Fibrose/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Necrose/etiologia , Projetos Piloto , Próstata/patologia , Antígeno Prostático Específico/sangue , Resultado do Tratamento
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