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1.
Am J Physiol Endocrinol Metab ; 326(3): E366-E381, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38197792

RESUMO

Mammalian oocytes develop and mature in a mutually dependent relationship with surrounding cumulus cells. The oocyte actively regulates cumulus cell differentiation and function by secreting soluble paracrine oocyte-secreted factors (OSFs). We characterized the molecular mechanisms by which two model OSFs, cumulin and BMP15, regulate oocyte maturation and cumulus-oocyte cooperativity. Exposure to these OSFs during mouse oocyte maturation in vitro altered the proteomic and multispectral autofluorescence profiles of both the oocyte and cumulus cells. In oocytes, cumulin significantly upregulated proteins involved in nuclear function. In cumulus cells, both OSFs elicited marked upregulation of a variety of metabolic processes (mostly anabolic), including lipid, nucleotide, and carbohydrate metabolism, whereas mitochondrial metabolic processes were downregulated. The mitochondrial changes were validated by functional assays confirming altered mitochondrial morphology, respiration, and content while maintaining ATP homeostasis. Collectively, these data demonstrate that cumulin and BMP15 remodel cumulus cell metabolism, instructing them to upregulate their anabolic metabolic processes, while routine cellular functions are minimized in the oocyte during maturation, in preparation for ensuing embryonic development.NEW & NOTEWORTHY Oocyte-secreted factors (OSFs) promote oocyte and cumulus cell cooperativity by altering the molecular composition of both cell types. OSFs downregulate protein catabolic processes and upregulate processes associated with DNA binding, translation, and ribosome assembly in oocytes. In cumulus cells, OSFs alter mitochondrial number, morphology, and function, and enhance metabolic plasticity by upregulating anabolic pathways. Hence, the oocyte via OSFs, instructs cumulus cells to increase metabolic processes on its behalf, thereby subduing oocyte metabolism.


Assuntos
Células do Cúmulo , Proteômica , Gravidez , Feminino , Animais , Camundongos , Células do Cúmulo/metabolismo , Oócitos/metabolismo , Comunicação Celular , Desenvolvimento Embrionário , Técnicas de Maturação in Vitro de Oócitos , Mamíferos
2.
Int J Mol Sci ; 25(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38892017

RESUMO

The impact of age on mesenchymal stromal cell (MSC) characteristics has been well researched. However, increased age is concomitant with increased prevalence of polypharmacy. This adjustable factor may have further implications for the functionality of MSCs and the effectiveness of autologous MSC procedures. We applied hyperspectral microscopy of cell autofluorescence-a non-invasive imaging technique used to characterise cytometabolic heterogeneity-to identify changes in the autofluorescence signals of MSCs from (1) young mice, (2) old mice, (3) young mice randomised to receive polypharmacy (9-10 weeks of oral therapeutic doses of simvastatin, metoprolol, oxycodone, oxybutynin and citalopram), and (4) old mice randomised to receive polypharmacy. Principal Component Analysis and Logistic Regression Analysis were used to assess alterations in spectral and associated metabolic characteristics. Modelling demonstrated that cells from young mice receiving polypharmacy had less NAD(P)H and increased porphyrin relative to cells from old control mice, allowing for effective separation of the two groups (AUC of ROC curve > 0.94). Similarly, cells from old polypharmacy mice were accurately separated from those from young controls due to lower levels of NAD(P)H (p < 0.001) and higher porphyrin (p < 0.001), allowing for an extremely accurate logistic regression (AUC of ROC curve = 0.99). This polypharmacy regimen may have a more profound impact on MSCs than ageing, and can simultaneously reduce optical redox ratio (ORR) and increase porphyrin levels. This has implications for the use of autologous MSCs for older patients with chronic disease.


Assuntos
Envelhecimento , Células-Tronco Mesenquimais , Polimedicação , Animais , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos , Envelhecimento/metabolismo , Masculino , Imagem Óptica/métodos , NADP/metabolismo
3.
Biogerontology ; 23(2): 237-249, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35211812

RESUMO

Increasing age has a major detrimental impact on female fertility, which, with an ageing population, has major sociological implications. This impact is primarily mediated through deteriorating quality of the oocyte. Deteriorating oocyte quality with biological age is the greatest rate-limiting factor to female fertility. Here we have used label-free, non-invasive multi-spectral imaging to identify unique autofluorescence profiles of oocytes from young and aged animals. Discriminant analysis demonstrated that young oocytes have a distinct autofluorescent profile which accurately distinguishes them from aged oocytes. We recently showed that treatment with the nicotinamide adenine dinucleotide (NAD+) precursor nicotinamide mononucleotide (NMN) restored oocyte quality and fertility in aged animals, and when our analysis was applied to oocytes from aged animals treated with NMN, 85% of these oocytes were classified as having the autofluorescent signature of young animals. Spectral unmixing using the Robust Dependent Component Analysis (RoDECA) algorithm demonstrated that NMN treatment altered the metabolic profile of oocytes, increasing free NAD(P)H, protein bound NAD(P)H, redox ratio and the ratio of bound to free NAD(P)H. The frequency of oocytes with simultaneously high NAD(P)H and flavin content was also significantly increased in mice treated with NMN. Young and Aged + NMN oocytes had a smoother spectral distribution, with the distribution of NAD(P)H in young oocytes specifically differing from that of aged oocytes. Identifying the multispectral profile of oocyte autofluorescence during aging could have utility as a non-invasive and sensitive measure of oocyte quality.


Assuntos
NAD , Oócitos , Envelhecimento , Animais , Feminino , Fertilidade , Camundongos , NAD/metabolismo , Mononucleotídeo de Nicotinamida , Oócitos/metabolismo
4.
Hum Reprod ; 37(1): 14-29, 2021 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-34741175

RESUMO

STUDY QUESTION: Can label-free, non-invasive optical imaging by hyperspectral autofluorescence microscopy discern between euploid and aneuploid cells within the inner cell mass (ICM) of the mouse preimplantation embryo? SUMMARY ANSWER: Hyperspectral autofluorescence microscopy enables discrimination between euploid and aneuploid ICM in mouse embryos. WHAT IS KNOWN ALREADY: Euploid/aneuploid mosaicism affects up to 17.3% of human blastocyst embryos with trophectoderm biopsy or spent media currently utilized to diagnose aneuploidy and mosaicism in clinical in vitro fertilization. Based on their design, these approaches will fail to diagnose the presence or proportion of aneuploid cells within the foetal lineage ICM of some blastocyst embryos. STUDY DESIGN, SIZE, DURATION: The impact of aneuploidy on cellular autofluorescence and metabolism of primary human fibroblast cells and mouse embryos was assessed using a fluorescence microscope adapted for imaging with multiple spectral channels (hyperspectral imaging). Primary human fibroblast cells with known ploidy were subjected to hyperspectral imaging to record native cell fluorescence (4-6 independent replicates, euploid n = 467; aneuploid n = 969). For mouse embryos, blastomeres from the eight-cell stage (five independent replicates: control n = 39; reversine n = 44) and chimeric blastocysts (eight independent replicates: control n = 34; reversine n = 34; 1:1 (control:reversine) n = 30 and 1:3 (control:reversine) n = 37) were utilized for hyperspectral imaging. The ICM from control and reversine-treated embryos were mechanically dissected and their karyotype confirmed by whole genome sequencing (n = 13 euploid and n = 9 aneuploid). PARTICIPANTS/MATERIALS, SETTING, METHODS: Two models were employed: (i) primary human fibroblasts with known karyotype and (ii) a mouse model of embryo aneuploidy where mouse embryos were treated with reversine, a reversible spindle assembly checkpoint inhibitor, during the four- to eight-cell division. Individual blastomeres were dissociated from control and reversine-treated eight-cell embryos and either imaged directly or used to generate chimeric blastocysts with differing ratios of control:reversine-treated cells. Individual blastomeres and embryos were interrogated by hyperspectral imaging. Changes in cellular metabolism were determined by quantification of metabolic co-factors (inferred from their autofluorescence signature): NAD(P)H and flavins with the subsequent calculation of the optical redox ratio (ORR: flavins/[NAD(P)H + flavins]). Autofluorescence signals obtained from hyperspectral imaging were examined mathematically to extract features from each cell/blastomere/ICM. This was used to discriminate between different cell populations. MAIN RESULTS AND THE ROLE OF CHANCE: An increase in the relative abundance of NAD(P)H and decrease in flavins led to a significant reduction in the ORR for aneuploid cells in primary human fibroblasts and reversine-treated mouse blastomeres (P < 0.05). Mathematical analysis of endogenous cell autofluorescence achieved separation between (i) euploid and aneuploid primary human fibroblast cells, (ii) control and reversine-treated mouse blastomeres cells, (iii) control and reversine-treated chimeric blastocysts, (iv) 1:1 and 1:3 chimeric blastocysts and (v) confirmed euploid and aneuploid ICM from mouse blastocysts. The accuracy of these separations was supported by receiver operating characteristic curves with areas under the curve of 0.97, 0.99, 0.87, 0.88 and 0.93, respectively. We believe that the role of chance is low as mathematical features separated euploid from aneuploid in both human fibroblasts and ICM of mouse blastocysts. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Although we were able to discriminate between euploid and aneuploid ICM in mouse blastocysts, confirmation of this approach in human embryos is required. While we show this approach is safe in mouse, further validation is required in large animal species prior to implementation in a clinical setting. WIDER IMPLICATIONS OF THE FINDINGS: We have developed an original, accurate and non-invasive optical approach to assess aneuploidy within the ICM of mouse embryos in the absence of fluorescent tags. Hyperspectral autofluorescence imaging was able to discriminate between euploid and aneuploid human fibroblast and mouse blastocysts (ICM). This approach may potentially lead to a new diagnostic for embryo analysis. STUDY FUNDING/COMPETING INTEREST(S): K.R.D. is supported by a Mid-Career Fellowship from the Hospital Research Foundation (C-MCF-58-2019). This study was funded by the Australian Research Council Centre of Excellence for Nanoscale Biophotonics (CE140100003) and the National Health and Medical Research Council (APP2003786). The authors declare that there is no conflict of interest.


Assuntos
Diagnóstico Pré-Implantação , Aneuploidia , Animais , Austrália , Blastocisto/metabolismo , Feminino , Fertilização in vitro/métodos , Camundongos , Gravidez , Diagnóstico Pré-Implantação/métodos
5.
BMC Cancer ; 19(1): 1242, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31864316

RESUMO

BACKGROUND: Cell cycle analysis is important for cancer research. However, available methodologies have drawbacks including limited categorisation and reliance on fixation, staining or transformation. Multispectral analysis of endogenous cell autofluorescence has been shown to be sensitive to changes in cell status and could be applied to the discrimination of cell cycle without these steps. METHODS: Cells from the MIA-PaCa-2, PANC-1, and HeLa cell lines were plated on gridded dishes and imaged using a multispectral fluorescence microscope. They were then stained for proliferating cell nuclear antigen (PCNA) and DNA intensity as a reference standard for their cell cycle position (G1, S, G2, M). The multispectral data was split into training and testing datasets and models were generated to discriminate between G1, S, and G2 + M phase cells. A standard decision tree classification approach was taken, and a two-step system was generated for each line. RESULTS: Across cancer cell lines accuracy ranged from 68.3% (MIA-PaCa-2) to 73.3% (HeLa) for distinguishing G1 from S and G2 + M, and 69.0% (MIA-PaCa-2) to 78.0% (PANC1) for distinguishing S from G2 + M. Unmixing the multispectral data showed that the autofluorophores NADH, FAD, and PPIX had significant differences between phases. Similarly, the redox ratio and the ratio of protein bound to free NADH were significantly affected. CONCLUSIONS: These results demonstrate that multispectral microscopy could be used for the non-destructive, label free discrimination of cell cycle phase in cancer cells. They provide novel information on the mechanisms of cell-cycle progression and control, and have practical implications for oncology research.


Assuntos
Ciclo Celular , Microscopia de Fluorescência/métodos , Neoplasias/patologia , Imagem Óptica/métodos , Linhagem Celular Tumoral , Células HeLa , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo
6.
J Med Internet Res ; 19(12): e406, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29233804

RESUMO

BACKGROUND: Chronic noncommunicable diseases (NCDs) such as asthma, diabetes, cancer, and persistent musculoskeletal pain impose an escalating and unsustainable burden on young people, their families, and society. Exploring how mobile health (mHealth) technologies can support management for young people with NCDs is imperative. OBJECTIVE: The aim of this study was to identify, appraise, and synthesize available qualitative evidence on users' experiences of mHealth technologies for NCD management in young people. We explored the perspectives of both end users (young people) and implementers (health policy makers, clinicians, and researchers). METHODS: A systematic review and meta-synthesis of qualitative studies. Eligibility criteria included full reports published in peer-reviewed journals from January 2007 to December 2016, searched across databases including EMBASE, MEDLINE (PubMed), Scopus, and PsycINFO. All qualitative studies that evaluated the use of mHealth technologies to support young people (in the age range of 15-24 years) in managing their chronic NCDs were considered. Two independent reviewers identified eligible reports and conducted critical appraisal (based on the Joanna Briggs Institute Qualitative Assessment and Review Instrument: JBI-QARI). Three reviewers independently, then collaboratively, synthesized and interpreted data through an inductive and iterative process to derive emergent themes across the included data. External validity checking was undertaken by an expert clinical researcher and for relevant content, a health policy expert. Themes were subsequently subjected to a meta-synthesis, with findings compared and contrasted between user groups and policy and practice recommendations derived. RESULTS: Twelve studies met our inclusion criteria. Among studies of end users (N=7), mHealth technologies supported the management of young people with diabetes, cancer, and asthma. Implementer studies (N=5) covered the management of cognitive and communicative disabilities, asthma, chronic self-harm, and attention deficit hyperactivity disorder. Quality ratings were higher for implementer compared with end user studies. Both complementary and unique user themes emerged. Themes derived for end users of mHealth included (1) Experiences of functionality that supported self-management, (2) Acceptance (technical usability and feasibility), (3) Importance of codesign, and (4) Perceptions of benefit (self-efficacy and empowerment). For implementers, derived themes included (1) Characteristics that supported self-management (functional, technical, and behavior change); (2) Implementation challenges (systems level, service delivery level, and clinical level); (3) Adoption considerations for specific populations (training end users; specific design requirements); and (4) Codesign and tailoring to facilitate uptake and person-centered care. CONCLUSIONS: Synthesizing available data revealed both complementary and unique user perspectives on enablers and barriers to designing, developing, and implementing mHealth technologies to support young people's management of their chronic NCDs. TRIAL REGISTRATION: PROSPERO CRD42017056317; http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD 42017056317 (Archived by WebCite at http://www.webcitation.org/6vZ5UkKLp).


Assuntos
Telemedicina/estatística & dados numéricos , Adolescente , Adulto , Doença Crônica , Humanos , Pesquisa Qualitativa , Adulto Jovem
7.
Reprod Biomed Online ; 31(5): 593-604, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26380863

RESUMO

This systematic review investigated the effect of paternal obesity on reproductive potential. Databases searched were Pubmed, Ovid, Web of Science, Scopus, Cinahl and Embase. Papers were critically appraised by two reviewers, and data were extracted using a standardized tool. Outcomes were: likelihood of infertility, embryo development, clinical pregnancy, live birth, pregnancy viability, infant development, sperm; concentration, morphology, motility, volume, DNA fragmentation, chromatin condensation, mitochondrial membrane potential (MMP), and seminal plasma factors. Thirty papers were included, with a total participant number of 115,158. Obese men were more likely to experience infertility (OR = 1.66, 95% CI 1.53-1.79), their rate of live birth per cycle of assisted reproduction technology (ART) was reduced (OR = 0.65, 95% CI 0.44-0.97) and they had a 10% absolute risk increase of pregnancy non-viability. Additionally, obese men had an increased percentage of sperm with low MMP, DNA fragmentation, and abnormal morphology. Clinically significant differences were not found for conventional semen parameters. From these findings it can be concluded that male obesity is associated with reduced reproductive potential. Furthermore, it may be informative to incorporate DNA fragmentation analysis and MMP assessment into semen testing, especially for obese men whose results suggest they should have normal fertility.


Assuntos
Fertilidade/fisiologia , Infertilidade Masculina/fisiopatologia , Obesidade/fisiopatologia , Técnicas de Reprodução Assistida , Espermatozoides/fisiologia , Fragmentação do DNA , Feminino , Humanos , Masculino , Gravidez , Análise do Sêmen , Motilidade dos Espermatozoides/fisiologia
8.
Worldviews Evid Based Nurs ; 12(6): 313-27, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26629973

RESUMO

OBJECTIVE: Clinicians and other healthcare professionals need access to summaries of evidence-based information in order to provide effective care to their patients at the point-of-care. Evidence-based practice (EBP) point-of-care resources have been developed and are available online to meet this need. This study aimed to develop a comprehensive list of available EBP point-of-care resources and evaluate their processes and policies for the development of content, in order to provide a critical analysis based upon rigor, transparency and measures of editorial quality to inform healthcare providers and promote quality improvement amongst publishers of EBP resources. DESIGN: A comprehensive and systematic search (Pubmed, CINAHL, and Cochrane Central) was undertaken to identify available EBP point-of-care resources, defined as "web-based medical compendia specifically designed to deliver predigested, rapidly accessible, comprehensive, periodically updated, and evidence-based information (and possibly also guidance) to clinicians." MAIN OUTCOME MEASURES: A pair of investigators independently extracted information on general characteristics, content presentation, editorial quality, evidence-based methodology, and breadth and volume. RESULTS: Twenty-seven summary resources were identified, of which 22 met the predefined inclusion criteria for EBP point-of-care resources, and 20 could be accessed for description and assessment. Overall, the upper quartile of EBP point-of-care providers was assessed to be UpToDate, Nursing Reference Centre, Mosby's Nursing Consult, BMJ Best Practice, and JBI COnNECT+. LINKING EVIDENCE TO ACTION: The choice of which EBP point-of-care resources are suitable for an organization is a decision that depends heavily on the unique requirements of that organization and the resources it has available. However, the results presented in this study should enable healthcare providers to make that assessment in a clear, evidence-based manner, and provide a comprehensive list of the available options.


Assuntos
Enfermagem Baseada em Evidências/métodos , Pessoal de Saúde/educação , Serviços de Informação/normas , Sistemas Automatizados de Assistência Junto ao Leito/normas , Bases de Dados Bibliográficas/normas , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos , Internet
9.
Adv Mater ; : e2403761, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775184

RESUMO

Autofluorophores are endogenous fluorescent compounds that naturally occur in the intra and extracellular spaces of all tissues and organs. Most have vital biological functions - like the metabolic cofactors NAD(P)H and FAD+, as well as the structural protein collagen. Others are considered to be waste products - like lipofuscin and advanced glycation end products - which accumulate with age and are associated with cellular dysfunction. Due to their natural fluorescence, these materials have great utility for enabling non-invasive, label-free assays with direct ties to biological function. Numerous technologies, with different advantages and drawbacks, are applied to their assessment, including fluorescence lifetime imaging microscopy, hyperspectral microscopy, and flow cytometry. Here, the applications of label-free autofluorophore assessment are reviewed for clinical and health-research applications, with specific attention to biomaterials, disease detection, surgical guidance, treatment monitoring, and tissue assessment - fields that greatly benefit from non-invasive methodologies capable of continuous, in vivo characterization.

10.
J Reprod Dev ; 59(2): 131-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23171593

RESUMO

Human embryos for hESC derivation are often donated at the cleavage stage and of reduced quality. Poor quality embryos have lower efficiency for hESC derivation. However, cleavage stage mouse embryos develop into higher quality expanded blastocysts if they are cultured with insulin, suggesting that this approach could be used to improve hESC derivation from poor quality cleavage stage embryos. The present study used a mouse model to examine this approach. In particular we examined the effect of insulin on the number of epiblast cells in blastocysts on days 4, 5 and 6 using Oct4 and Nanog co-expression. Second we examined the effect of insulin on the frequency with which outgrowths can be derived from these. Finally, we tested whether prior culture in the presence of insulin results in blastocysts with increased capacity to generate ESC colonies. Culture of cleavage stage embryos with insulin increased the number of Oct4 and Nanog positive cells in blastocysts at all time points examined. Prior culture with insulin had no effect on outgrowths generated from blastocysts plated on days 4 or 5. However, insulin treatment of blastocysts plated on day 6 resulted in increased numbers of outgrowths with larger epiblasts compared with controls. 13% of insulin treated day 6 blastocysts produced primary ESC colonies compared with 6% of controls. In conclusion, treatment with insulin can improve epiblast cell number in mice leading to an increase with which primary ESC colonies can be generated and may improve hESC isolation from reduced quality embryos donated at the cleavage stage.


Assuntos
Técnicas de Cultura Embrionária/métodos , Células-Tronco Embrionárias/efeitos dos fármacos , Camadas Germinativas/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Animais , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Blastocisto/metabolismo , Contagem de Células , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Camadas Germinativas/citologia , Camadas Germinativas/metabolismo , Proteínas de Homeodomínio/metabolismo , Camundongos , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/metabolismo
11.
J Biophotonics ; 16(4): e202200264, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36602432

RESUMO

Hyperspectral and multispectral imaging of cell and tissue autofluorescence employs fluorescence imaging, without exogenous fluorophores, across multiple excitation/emission combinations (spectral channels). This produces an image stack where each pixel (matched by location) contains unique information about the sample's spectral properties. Analysis of this data enables access to a rich, molecularly specific data set from a broad range of cell-native fluorophores (autofluorophores) directly reflective of biochemical status, without use of fixation or stains. This non-invasive, non-destructive technology has great potential to spare the collection of biopsies from sensitive regions. As both staining and biopsy may be impossible, or undesirable, depending on the context, this technology great diagnostic potential for clinical decision making. The main research focus has been on the identification of neoplastic tissues. However, advances have been made in diverse applications-including ophthalmology, cardiovascular health, neurology, infection, assisted reproduction technology and organ transplantation.


Assuntos
Imageamento Hiperespectral , Imagem Óptica
12.
J Biophotonics ; 16(9): e202300105, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37272291

RESUMO

Hyperspectral and multispectral imaging of cell and tissue autofluorescence is an emerging technology in which fluorescence imaging is applied to biological materials across multiple spectral channels. This produces a stack of images where each matched pixel contains information about the sample's spectral properties at that location. This allows precise collection of molecularly specific data from a broad range of native fluorophores. Importantly, complex information, directly reflective of biological status, is collected without staining and tissues can be characterised in situ, without biopsy. For oncology, this can spare the collection of biopsies from sensitive regions and enable accurate tumour mapping. For in vivo tumour analysis, the greatest focus has been on oral cancer, whereas for ex vivo assessment head-and-neck cancers along with colon cancer have been the most studied, followed by oral and eye cancer. This review details the scope and progress of research undertaken towards clinical translation in oncology.


Assuntos
Neoplasias do Colo , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Imageamento Hiperespectral , Neoplasias Bucais/diagnóstico por imagem , Imagem Óptica
13.
Comput Struct Biotechnol J ; 21: 1851-1859, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36915378

RESUMO

Islets transplanted for type-1 diabetes have their viability reduced by warm ischemia, dimethyloxalylglycine (DMOG; hypoxia model), oxidative stress and cytokine injury. This results in frequent transplant failures and the major burden of patients having to undergo multiple rounds of treatment for insulin independence. Presently there is no reliable measure to assess islet preparation viability prior to clinical transplantation. We investigated deep morphological signatures (DMS) for detecting the exposure of islets to viability compromising insults from brightfield images. Accuracies ranged from 98 % to 68 % for; ROS damage, pro-inflammatory cytokines, warm ischemia and DMOG. When islets were disaggregated to single cells to enable higher throughput data collection, good accuracy was still obtained (83-71 %). Encapsulation of islets reduced accuracy for cytokine exposure, but it was still high (78 %). Unsupervised modelling of the DMS for islet preparations transplanted into a syngeneic mouse model was able to predict whether or not they would restore glucose control with 100 % accuracy. Our strategy for constructing DMS' is effective for the assessment of islet pre-transplant viability. If translated into the clinic, standard equipment could be used to prospectively identify non-functional islet preparations unable to contribute to the restoration of glucose control and reduce the burden of unsuccessful treatments.

14.
Cells ; 12(18)2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37759524

RESUMO

Islets prepared for transplantation into type 1 diabetes patients are exposed to compromising intrinsic and extrinsic factors that contribute to early graft failure, necessitating repeated islet infusions for clinical insulin independence. A lack of reliable pre-transplant measures to determine islet viability severely limits the success of islet transplantation and will limit future beta cell replacement strategies. We applied hyperspectral fluorescent microscopy to determine whether we could non-invasively detect islet damage induced by oxidative stress, hypoxia, cytokine injury, and warm ischaemia, and so predict transplant outcomes in a mouse model. In assessing islet spectral signals for NAD(P)H, flavins, collagen-I, and cytochrome-C in intact islets, we distinguished islets compromised by oxidative stress (ROS) (AUC = 1.00), hypoxia (AUC = 0.69), cytokine exposure (AUC = 0.94), and warm ischaemia (AUC = 0.94) compared to islets harvested from pristine anaesthetised heart-beating mouse donors. Significantly, with unsupervised assessment we defined an autofluorescent score for ischaemic islets that accurately predicted the restoration of glucose control in diabetic recipients following transplantation. Similar results were obtained for islet single cell suspensions, suggesting translational utility in the context of emerging beta cell replacement strategies. These data show that the pre-transplant hyperspectral imaging of islet autofluorescence has promise for predicting islet viability and transplant success.


Assuntos
Células Secretoras de Insulina , Ilhotas Pancreáticas , Humanos , Animais , Camundongos , Imageamento Hiperespectral , Ilhotas Pancreáticas/diagnóstico por imagem , Citocinas , Hipóxia
15.
Nutrients ; 14(15)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35956406

RESUMO

The preservation of cognitive ability by increasing nicotinamide adenine dinucleotide (NAD+) levels through supplementation with NAD+ precursors has been identified as a promising treatment strategy for a number of conditions; principally, age-related cognitive decline (including Alzheimer's disease and vascular dementia), but also diabetes, stroke, and traumatic brain injury. Candidate factors have included NAD+ itself, its reduced form NADH, nicotinamide (NAM), nicotinamide mononucleotide (NMN), nicotinamide riboside (NR), and niacin (or nicotinic acid). This review summarises the research findings for each source of cognitive impairment for which NAD+ precursor supplementation has been investigated as a therapy. The findings are mostly positive but have been made primarily in animal models, with some reports of null or adverse effects. Given the increasing popularity and availability of these factors as nutritional supplements, further properly controlled clinical research is needed to provide definitive answers regarding this strategy's likely impact on human cognitive health when used to address different sources of impairment.


Assuntos
Disfunção Cognitiva , Niacina , Animais , Disfunção Cognitiva/prevenção & controle , Suplementos Nutricionais , Humanos , NAD , Niacinamida , Mononucleotídeo de Nicotinamida
16.
Biomedicines ; 10(7)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35884850

RESUMO

The purpose of this study is to develop a deep radiomic signature based on an artificial intelligence (AI) model. This radiomic signature identifies oocyte morphological changes corresponding to reproductive aging in bright field images captured by optical light microscopy. Oocytes were collected from three mice groups: young (4- to 5-week-old) C57BL/6J female mice, aged (12-month-old) mice, and aged mice treated with the NAD+ precursor nicotinamide mononucleotide (NMN), a treatment recently shown to rejuvenate aspects of fertility in aged mice. We applied deep learning, swarm intelligence, and discriminative analysis to images of mouse oocytes taken by bright field microscopy to identify a highly informative deep radiomic signature (DRS) of oocyte morphology. Predictive DRS accuracy was determined by evaluating sensitivity, specificity, and cross-validation, and was visualized using scatter plots of the data associated with three groups: Young, old and Old + NMN. DRS could successfully distinguish morphological changes in oocytes associated with maternal age with 92% accuracy (AUC~1), reflecting this decline in oocyte quality. We then employed the DRS to evaluate the impact of the treatment of reproductively aged mice with NMN. The DRS signature classified 60% of oocytes from NMN-treated aged mice as having a 'young' morphology. In conclusion, the DRS signature developed in this study was successfully able to detect aging-related oocyte morphological changes. The significance of our approach is that DRS applied to bright field oocyte images will allow us to distinguish and select oocytes originally affected by reproductive aging and whose quality has been successfully restored by the NMN therapy.

17.
Geroscience ; 43(2): 859-868, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32789662

RESUMO

Stem cell exhaustion plays a major role in the ageing of different tissues. Similarly, in vitro cell ageing during expansion prior to their use in regenerative medicine can severely compromise stem cell quality through progressive declines in differentiation and growth capacity. We utilized non-destructive multispectral assessment of native cell autofluorescence to investigate the metabolic mechanisms of in vitro mesenchymal stem cell (MSC) ageing in human bone marrow MSCs over serial passages (P2-P10). The spectral signals for NAD(P)H, flavins and protein-bound NAD(P)H were successfully isolated using Robust Dependent Component Analysis (RoDECA). NAD(P)H decreased over the course of hMSC ageing in absolute terms as well as relative to flavins (optical redox ratio). Relative changes in other fluorophore levels (flavins, protein-bound NAD(P)H) suggested that this reduction was due to nicotinamide adenine dinucleotide depletion rather than a metabolic shift from glycolysis to oxidative phosphorylation. Using multispectral features, which are determined without cell fixation or fluorescent labelling, we developed and externally validated a reliable, linear model which could accurately categorize the age of culture-expanded hMSCs. The largest shift in spectral characteristics occurs early in hMSC ageing. These findings demonstrate the feasibility of applying multispectral technology for the non-invasive monitoring of MSC health in vitro.


Assuntos
Envelhecimento , Células-Tronco Mesenquimais , NADP , Diferenciação Celular , Humanos , Células-Tronco Mesenquimais/metabolismo , Fosforilação Oxidativa
18.
Sci Rep ; 11(1): 10655, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34017033

RESUMO

Optimally preserved urinary exfoliated renal proximal tubule cells were assessed by multispectral imaging of cell autofluorescence. We demonstrated different multispectral autofluorescence signals in such cells extracted from the urine of patients with healthy or diseased kidneys. Using up to 10 features, we were able to differentiate cells from individuals with heathy kidneys and impaired renal function (indicated by estimated glomerular filtration rate (eGFR) values) with the receiver operating characteristic area under the curve (AUC) of 0.99. Using the same method, we were also able to discriminate such urine cells from patients with and without renal fibrosis on biopsy, where significant differences in multispectral autofluorescence signals (AUC = 0.90) were demonstrated between healthy and diseased patients (p < 0.05). These findings show that multispectral assessment of the cell autofluorescence in urine exfoliated proximal tubule kidney cells has the potential to be developed as a sensitive, non-invasive diagnostic method for CKD.


Assuntos
Rim/citologia , Rim/diagnóstico por imagem , Urina/citologia , Antígenos CD13/metabolismo , Diferenciação Celular , Linhagem Celular , Sobrevivência Celular , Taxa de Filtração Glomerular , Humanos , Rim/patologia , Túbulos Renais Proximais/citologia , Transportador 2 de Glucose-Sódio/metabolismo , Espectrometria de Fluorescência
19.
Adv Sci (Weinh) ; 7(24): 2003584, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33344143

RESUMO

Engineered nanomaterials that produce reactive oxygen species on exposure to X- and gamma-rays used in radiation therapy offer promise of novel cancer treatment strategies. Similar to photodynamic therapy but suitable for large and deep tumors, this new approach where nanomaterials acting as sensitizing agents are combined with clinical radiation can be effective at well-tolerated low radiation doses. Suitably engineered nanomaterials can enhance cancer radiotherapy by increasing the tumor selectivity and decreasing side effects. Additionally, the nanomaterial platform offers therapeutically valuable functionalities, including molecular targeting, drug/gene delivery, and adaptive responses to trigger drug release. The potential of such nanomaterials to be combined with radiotherapy is widely recognized. In order for further breakthroughs to be made, and to facilitate clinical translation, the applicable principles and fundamentals should be articulated. This review focuses on mechanisms underpinning rational nanomaterial design to enhance radiation therapy, the understanding of which will enable novel ways to optimize its therapeutic efficacy. A roadmap for designing nanomaterials with optimized anticancer performance is also shown and the potential clinical significance and future translation are discussed.

20.
Pathol Oncol Res ; 26(3): 1367-1375, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30875031

RESUMO

The ISUP (Internal Society of Urologic Pathology) recently adopted a five-tiered prognostication system. There is evidence to suggest that the ISUP grade group 4 is a heterogeneous entity regarding prognosis. Our aim was to systematically examine the existing evidence to determine if outcome differences exist within the ISUP grade group 4. A systematic search of the literature for all studies examining the heterogeneity of the ISUP grade group 4 was conducted. Available studies were combined with meta-analysis to evaluate prognostic differences within the ISUP grade group 4 measured by all-cause mortality (ACM) and the prostate cancer-specific mortality (PCSM). Eight studies were identified and utilised a variety of outcome measures to answer the question of heterogeneity within the ISUP grade group 4. Four of these studies examined prognosis using both ACM and PCSM. These were combined into a meta-analysis. The combined group of 5 + 3/3 + 5 had statistically significant higher ACM (hazard ratio [HR] 1.23, 95% confidence internal [Cl] 1.08-1.41) when compared to the 4 + 4 group. There was no difference in the PCSM between the two groups (HR 1.34, 95% CI 0.89-2.01). However, heterogeneity was high for this analysis secondary to a range of methodological differences. Our meta-analysis showed that Gleason grade 3 + 5/5 + 3 had higher ACM than Gleason grade group 4 + 4. Measures of PCSM were statistically insignificant, although heterogeneity was high. Evidence suggests that heterogeneity is likely, although inconclusive. Further studies with consistent methodologies are required to answer this question.


Assuntos
Gradação de Tumores , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Humanos , Masculino , Prognóstico
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