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1.
Int J Obes (Lond) ; 46(3): 502-514, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34764426

RESUMO

OBJECTIVES: Lipedema, a poorly understood chronic disease of adipose hyper-deposition, is often mistaken for obesity and causes significant impairment to mobility and quality-of-life. To identify molecular mechanisms underpinning lipedema, we employed comprehensive omics-based comparative analyses of whole tissue, adipocyte precursors (adipose-derived stem cells (ADSCs)), and adipocytes from patients with or without lipedema. METHODS: We compared whole-tissues, ADSCs, and adipocytes from body mass index-matched lipedema (n = 14) and unaffected (n = 10) patients using comprehensive global lipidomic and metabolomic analyses, transcriptional profiling, and functional assays. RESULTS: Transcriptional profiling revealed >4400 significant differences in lipedema tissue, with altered levels of mRNAs involved in critical signaling and cell function-regulating pathways (e.g., lipid metabolism and cell-cycle/proliferation). Functional assays showed accelerated ADSC proliferation and differentiation in lipedema. Profiling lipedema adipocytes revealed >900 changes in lipid composition and >600 differentially altered metabolites. Transcriptional profiling of lipedema ADSCs and non-lipedema ADSCs revealed significant differential expression of >3400 genes including some involved in extracellular matrix and cell-cycle/proliferation signaling pathways. One upregulated gene in lipedema ADSCs, Bub1, encodes a cell-cycle regulator, central to the kinetochore complex, which regulates several histone proteins involved in cell proliferation. Downstream signaling analysis of lipedema ADSCs demonstrated enhanced activation of histone H2A, a key cell proliferation driver and Bub1 target. Critically, hyperproliferation exhibited by lipedema ADSCs was inhibited by the small molecule Bub1 inhibitor 2OH-BNPP1 and by CRISPR/Cas9-mediated Bub1 gene depletion. CONCLUSION: We found significant differences in gene expression, and lipid and metabolite profiles, in tissue, ADSCs, and adipocytes from lipedema patients compared to non-affected controls. Functional assays demonstrated that dysregulated Bub1 signaling drives increased proliferation of lipedema ADSCs, suggesting a potential mechanism for enhanced adipogenesis in lipedema. Importantly, our characterization of signaling networks driving lipedema identifies potential molecular targets, including Bub1, for novel lipedema therapeutics.


Assuntos
Lipedema , Adipócitos/metabolismo , Adipogenia/genética , Tecido Adiposo/metabolismo , Diferenciação Celular/fisiologia , Humanos , Lipedema/genética , Lipídeos
2.
Australas J Dermatol ; 59(3): 182-187, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28332194

RESUMO

BACKGROUND/OBJECTIVES: Sunlight is a major risk factor for cutaneous melanoma. However, its interaction with melanoma is complex. In particular, vitamin D is a UVB-derived hormone that has been shown to have anti-cancer effects. In this retrospective pilot study we sought to determine an association between the clinicopathological features of melanoma and the patients' corresponding serum vitamin D level. METHODS: In total, 109 primary melanomas diagnosed between 2001 and 2013 were retrospectively identified from our institutional database with a corresponding 25-hydroxyvitamin D3 level estimated within 6 months of diagnosis. Tumour, clinical (age, sex, tumour location) and pathological (thickness, mitosis, ulceration, Clark level, subtype, metastatic status) parameters were correlated with vitamin D. For statistical analysis, an unpaired Student's t-test and anova was used for categorical variables, and Spearman's correlation for continuous variables. RESULTS: Vitamin D level was inversely associated with Breslow thickness as a dichotomous, categorical and continuous variable. The association remained significant when controlled for patient's age and sex (P = 0.026). Vitamin D was higher in non-ulcerated tumours compared with ulcerated tumours (P = 0.006) and in tumours with mitotic rate <1/mm2 compared with ≥1/mm2 (P = 0.036). A significant association was found between vitamin D level and tumour histological subtype (P = 0.019). On subgroup analysis, significant associations were found between superficial spreading melanoma (SSM) and nodular melanoma (P = 0.026), and SSM and acral lentiginous melanoma (P = 0.007). CONCLUSION: A high vitamin D status may benefit prognosis in patients diagnosed with primary melanoma. A prospective cohort analysis with a large sample and controlled for other vitamin D confounders would validate these findings.


Assuntos
Calcifediol/sangue , Melanoma/sangue , Melanoma/patologia , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Melanoma/complicações , Pessoa de Meia-Idade , Índice Mitótico , Projetos Piloto , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/complicações , Úlcera Cutânea/etiologia
3.
Med J Aust ; 204(3): 114.e1-7, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26866551

RESUMO

OBJECTIVES: The incidence of animal bite injuries in Australia is high. There is currently no established method for reliably predicting whether a patient with a bite injury will require admission to hospital or surgery. DESIGN: A retrospective audit of mammalian bite injuries at seven major hospitals in Melbourne, Victoria, over a 2-year period. The associations between each predictor and outcome of interest were analysed with univariate and multiple regression analyses. SETTING: Seven major hospitals in Melbourne, Victoria: the Alfred Hospital, Austin Hospital, Frankston Hospital, Monash Medical Centre, Royal Melbourne Hospital, St Vincent's Hospital and Western Hospital. PARTICIPANTS: Patients presenting to emergency departments with mammalian bite injuries. MAIN OUTCOME MEASURES: Hospital admission, intravenous antibiotic therapy, surgery, reoperation, readmission. RESULTS: We identified 717 mammalian bite injuries. The mean age of the patients was 36.5 years (median, 34 years; range, 0-88 years), with an equal number of males and females. The overall rate of hospital admission was 50.8%, and the mean length of stay was 2.7 days. Intravenous antibiotics were administered in 46% of cases; surgery was undertaken in 43.1% of cases. The re-operation rate was 4.5%, the re-admission rate was 3%. CONCLUSIONS: Our study provides a detailed epidemiological analysis of animal bite injuries at seven major hospitals in Victoria. Risk factors for hospitalisation and surgery may assist in identifying patients who require admission and surgical intervention.


Assuntos
Mordeduras e Picadas/epidemiologia , Mordeduras e Picadas/cirurgia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Cães , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Vitória/epidemiologia
5.
Nature ; 456(7222): 643-7, 2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-18931657

RESUMO

The lymphatic system plays a key role in tissue fluid regulation and tumour metastasis, and lymphatic defects underlie many pathological states including lymphoedema, lymphangiectasia, lymphangioma and lymphatic dysplasia. However, the origins of the lymphatic system in the embryo, and the mechanisms that direct growth of the network of lymphatic vessels, remain unclear. Lymphatic vessels are thought to arise from endothelial precursor cells budding from the cardinal vein under the influence of the lymphatic hallmark gene Prox1 (prospero homeobox 1; ref. 4). Defects in the transcription factor gene SOX18 (SRY (sex determining region Y) box 18) cause lymphatic dysfunction in the human syndrome hypotrichosis-lymphoedema-telangiectasia, suggesting that Sox18 may also play a role in lymphatic development or function. Here we use molecular, cellular and genetic assays in mice to show that Sox18 acts as a molecular switch to induce differentiation of lymphatic endothelial cells. Sox18 is expressed in a subset of cardinal vein cells that later co-express Prox1 and migrate to form lymphatic vessels. Sox18 directly activates Prox1 transcription by binding to its proximal promoter. Overexpression of Sox18 in blood vascular endothelial cells induces them to express Prox1 and other lymphatic endothelial markers, while Sox18-null embryos show a complete blockade of lymphatic endothelial cell differentiation from the cardinal vein. Our findings demonstrate a critical role for Sox18 in developmental lymphangiogenesis, and suggest new avenues to investigate for therapeutic management of human lymphangiopathies.


Assuntos
Diferenciação Celular , Vasos Linfáticos/citologia , Vasos Linfáticos/embriologia , Fatores de Transcrição SOXF/metabolismo , Animais , Biomarcadores/análise , Movimento Celular , Células Cultivadas , Edema/genética , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Efrina-B2/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Hipotricose/genética , Linfangiogênese , Vasos Linfáticos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Regiões Promotoras Genéticas/genética , Fatores de Transcrição SOXF/deficiência , Fatores de Transcrição SOXF/genética , Telangiectasia/genética , Proteínas Supressoras de Tumor/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Veias/citologia
6.
Ann Plast Surg ; 73(3): 352-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23788141

RESUMO

BACKGROUND: Despite the widespread use of autologous fat grafting in both reconstructive and cosmetic surgery, volume retention remains a significant problem. We aimed to critically appraise the current body of literature in fat grafting to provide a framework to guide application and comparison. METHOD: Search of scientific databases and gray literature was conducted. Articles examining nonadipogenic applications of adipose tissue and those specific to breast reconstruction were excluded. RESULTS: One hundred three articles were included. These fell under the headings of donor site, effect of infiltration solution, harvest method, effect of centrifugation, reinjection method, supplementation, the role of adipose-derived stem cells, and scaffolding. CONCLUSIONS: Despite the significant research effort in this field, there remains no consensus as to the optimum technique. This stems from the vast array of research methods and short follow-up durations. Further, extrapolation of in vitro results to clinical settings has led to many conflicting practices.


Assuntos
Tecido Adiposo/transplante , Adipócitos , Humanos , Transplante Autólogo/métodos
7.
Plast Reconstr Surg Glob Open ; 12(1): e5547, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38268719

RESUMO

Background: Lymphedema is common after lymphatic damage in cancer treatment, with negative impacts on function and quality of life. Evidence suggests that blood vessel microvasculature is sensitive to irradiation and trauma; however, despite knowledge regarding dedicated mural blood supply to arteries and veins (vasa vasorum), equivalent blood vessels supplying lymphatics have not been characterized. We studied collecting lymphatics for dedicated mural blood vessels in our series of 500 lymphaticovenous anastomosis procedures for lymphedema, and equivalent controls. Methods: Microscopic images of lymphatics from lymphedema and control patients were analyzed for lymphatic wall vascular density. Collecting lymphatics from 20 patients with lymphedema and 10 control patients were sampled for more detailed analysis (podoplanin immunostaining, light/confocal microscopy, microcomputed tomography, and transmission electron microscopy) to assess lymphatic wall ultrastructure and blood supply. Results: Analysis revealed elaborate, dense blood microvessel networks associating with lymphatic walls in lymphedema patients and smaller equivalent vessels in controls. These vasa vasora or "arteria lymphatica" were supplied by regular axial blood vessels, parallel to lymphatic microperforators linking dermal and collecting lymphatics. Lymphatic walls were thicker in lymphedema patients than controls, with immunohistochemistry, computed tomography, transmission electron microscopy, and confocal microscopy characterizing abnormal blood vessels (altered appearance, thickened walls, elastin loss, narrow lumina, and fewer red blood cells) on these lymphatic walls. Conclusions: Dedicated blood vessels on lymphatics are significantly altered in lymphedema. A better understanding of the role of these vessels may reveal mechanistic clues into lymphedema pathophysiology and technical aspects of lymphedema microsurgery, and suggest potential novel therapeutic targets.

8.
Lymphat Res Biol ; 22(2): 106-111, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38407896

RESUMO

Background: Lipedema is a progressive condition involving excessive deposition of subcutaneous adipose tissue, predominantly in the lower limbs, which severely compromises quality of life. Despite the impact of lipedema, its molecular and genetic bases are poorly understood, making diagnosis and treatment difficult. Historical evaluation of individuals with lipedema indicates a positive family history in 60%-80% of cases; however, genetic investigation of larger family cohorts is required. Here, we report the largest family-based sequencing study to date, aimed at identifying genetic changes that contribute to lipedema. Methods and Results: DNA samples from 31 individuals from 9 lipedema families were analyzed to reveal genetic variants predicted to alter protein function, yielding candidate variants in 469 genes. We did not identify any individual genes that contained likely disease-causing variants across all participating families. However, gene ontology analysis highlighted vasopressin receptor activity, microfibril binding, and patched binding as statistically significantly overrepresented categories for the set of candidate variants. Conclusions: Our study suggests that lipedema is not caused by a single exomic genetic factor, providing support for the hypothesis of genetic heterogeneity in the etiology of lipedema. As the largest study of its kind in the lipedema field, the results advance our understanding of the disease and provide a roadmap for future research aimed at improving the lives of those affected by lipedema.


Assuntos
Lipedema , Humanos , Lipedema/diagnóstico , Qualidade de Vida , Gordura Subcutânea , Diagnóstico Diferencial
9.
Plast Reconstr Surg ; 152(3): 669-680, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36790779

RESUMO

BACKGROUND: Serendipitously, a dead giraffe provided opportunity to study its vascular anatomy. Comparative animal studies have revealed important information for designing new flaps and new microsurgical techniques. So, do giraffe's patches support a thermal window concept, do animals with similar markings and habitat have a similar thermoregulatory role, and could results offer new insight into human thermoregulation and free tissue transfer? METHODS: Previously described lead-oxide arterial-only injection studies, of a single giraffe, zebra, Africa wild dog, and spotted jaguar, all with wire-encircled pigmented patches; and archival human, pig, dog, cat, and rabbit studies, were compared. RESULTS: Each giraffe patch was supplied by just a single artery (angiosome) averaging 0.9 mm diameter, that divided near its center and sent dense, long, parallel, radiating spoke-wheel branches averaging 0.62 mm diameter to the patch margin, continuing as reduced-caliber choke anastomoses averaging 0.8 mm to link adjacent patch angiosomes. Uniquely arranged large veins, with an average of 1.66 mm, encircled the patches in the pale skin paralleled by arteriae comitantes averaging 0.22 mm. These arteries, connected to patch angiosomes, filled the veins intermittently by means of arteriovenous (A-V) shunts averaging 0.12 mm in diameter of magnitude never seen before in any species studied. None of the other three animals had angiosome territories matching their pigmented fur, or significant A-V filling. CONCLUSIONS: This study supports the "thermostatic" concept of the giraffe skin patches, with A-V shunts playing a major role. It affirms the need for further studies of these shunts in human thermoregulation and other flow regulations in physiology, pathology, and free tissue transfer.


Assuntos
Girafas , Humanos , Animais , Suínos , Coelhos , Regulação da Temperatura Corporal , Retalhos Cirúrgicos , Veias
10.
Front Pharmacol ; 14: 1152314, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37188266

RESUMO

Introduction: Surgery and radiotherapy are key cancer treatments and the leading causes of damage to the lymphatics, a vascular network critical to fluid homeostasis and immunity. The clinical manifestation of this damage constitutes a devastating side-effect of cancer treatment, known as lymphoedema. Lymphoedema is a chronic condition evolving from the accumulation of interstitial fluid due to impaired drainage via the lymphatics and is recognised to contribute significant morbidity to patients who survive their cancer. Nevertheless, the molecular mechanisms underlying the damage inflicted on lymphatic vessels, and particularly the lymphatic endothelial cells (LEC) that constitute them, by these treatment modalities, remain poorly understood. Methods: We used a combination of cell based assays, biochemistry and animal models of lymphatic injury to examine the molecular mechanisms behind LEC injury and the subsequent effects on lymphatic vessels, particularly the role of the VEGF-C/VEGF-D/VEGFR-3 lymphangiogenic signalling pathway, in lymphatic injury underpinning the development of lymphoedema. Results: We demonstrate that radiotherapy selectively impairs key LEC functions needed for new lymphatic vessel growth (lymphangiogenesis). This effect is mediated by attenuation of VEGFR-3 signalling and downstream signalling cascades. VEGFR-3 protein levels were downregulated in LEC that were exposed to radiation, and LEC were therefore selectively less responsive to VEGF-C and VEGF-D. These findings were validated in our animal models of radiation and surgical injury. Discussion: Our data provide mechanistic insight into injury sustained by LEC and lymphatics during surgical and radiotherapy cancer treatments and underscore the need for alternative non-VEGF-C/VEGFR-3-based therapies to treat lymphoedema.

11.
Histopathology ; 61(4): 702-10, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22734806

RESUMO

AIMS: Important prognostic factors in patients with cutaneous melanoma include primary tumour thickness/depth of invasion, ulceration and mitotic rate, and the presence of tumour cells in regional lymph nodes. More recently, features of stromal components, such as blood and lymphatic vessel density, have been suggested as additional indicators of metastatic potential. Our aim was to investigate the relationship between tumour lymphatic vessels and lymph node metastasis. METHODS AND RESULTS: Metastasizing (n = 11) and non-metastasizing (n = 11) primary melanoma samples matched for depth/thickness, mitotic rate and ulceration were examined for lymphatic vessel density (LVD) in the primary tumour, using an antibody to podoplanin. Significant differences were found between LVD (vessels/unit area) in the peripheral (5.73 ± 0.67) versus central (1.72 ± 0.42) regions of the metastasizing tumour group (P < 0.001), and between LVD in the peripheral areas of metastasizing (5.73 ± 0.67) versus non-metastasizing (4.21 ± 0.37) tumours (P < 0.01). No overall difference was found between total average LVD in the two tumour groups or between their vessel morphology. CONCLUSION: Our results show that LVD is associated with risk of lymph node metastasis. Furthermore, the ratio of peripheral LVD:central LVD is a useful marker of primary melanomas that are likely to metastasize to lymph nodes.


Assuntos
Linfangiogênese/fisiologia , Vasos Linfáticos/patologia , Melanoma/patologia , Invasividade Neoplásica/patologia , Neoplasias Cutâneas/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Biópsia de Linfonodo Sentinela
12.
Front Public Health ; 10: 789456, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493355

RESUMO

Health assessment data assists the well-being and patient care teams' process in drawing up a care and assistance plan and comprehending the requirements of the patient. Comprehensive and precise data about the Quality of Life of cancer patients play a significant part in the development and organization of cancer patient care. Quality of Life has been used to mean a variety of various things, such as health situation, physical function, symptoms, psychosocial modification, well-being, enjoyment of life, and happiness. Chronic diseases such as cancer are among the disorders that severely affect people's health and consequently their Quality of Life. Cancer patients experience a range of symptoms, including pain and various physical and mental conditions that negatively affect their Quality of Life. In this article, we examined cancer and the impact that this disease can have on the Quality of Life of cancer patients. The cancers examined in this article include head and neck, prostate, breast, lung, and skin cancers. We also discussed health assessment and the importance and purpose of studying patients' Quality of Life, especially cancer patients. The various signs and symptoms of the disease that affect the Quality of Life of patients were also reviewed.


Assuntos
Qualidade de Vida , Neoplasias Cutâneas , Adulto , Doença Crônica , Humanos , Pulmão , Masculino , Próstata
13.
Am J Clin Exp Immunol ; 11(1): 1-27, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35350450

RESUMO

Breast cancer is the most frequently happening cancer and the most typical cancer death among females. Despite the crucial progress in breast cancer therapy by using Chemotherapeutic agents, most anti-tumor drugs are insufficient to destroy exactly the breast cancer cells. The noble method of drug delivery using nanoparticles presents a great promise in treating breast cancer most sufficiently and with the least harm to the patient. Nanoparticles, with their spectacular characteristics, help overcome problems of this kind. Unique features of nanoparticles such as biocompatibility, bioavailability, biodegradability, sustained release, and, most importantly, site-specific targeting enables the Chemotherapeutic agents loaded in nanocarriers to differentiate between healthy tissue and cancer cells, leading to low toxicity and fewer side effects. This review focuses on evaluating and comprehending nanoparticles utilized in breast cancer treatment, including the most recent data related to the drugs they can carry. Also, this review covers all information related to each nanocarrier, such as their significant characteristics, subtypes, advantages, disadvantages, and chemical modification methods with recently published studies. This article discusses over 21 nanoparticles used in breast cancer treatment with possible chemical ligands such as monoclonal antibodies and chemotherapeutic agents binding to these carriers. These different nanoparticles and the unique features of each nanocarrier give the researchers all the data and insight to develop and use the brand-new drug delivery system.

15.
Data Brief ; 41: 107828, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35127999

RESUMO

Radiotherapy injury to cells of the skin and subcutaneous tissue is an inevitable consequence of external beam radiation for treatment of cancer. This sublethal injury to normal tissues plays a significant role in the development of fibrosis, lymphedema, impaired wound healing, and recurrent infections. To elucidate the transcriptional changes that occur in cells of the skin and soft tissues after radiotherapy injury, we performed genome-wide RNA-sequencing comparing irradiated cells (10Gy) with non-irradiated (0Gy) controls in normal human dermal fibroblasts, normal human keratinocytes, human microvascular endothelial cells, human dermal lymphatic endothelial cells, pericytes and adipose derived stem cell populations. These data are publicly available from the Gene Expression Omnibus database (accession number GSE184119). Further insights can be gained by comparing the mRNA signatures arising from radiation injury derived from these data to publicly available signatures from other studies involving similar or different tissue types. These global targets hold potential for manipulation to mitigate radiotherapy soft tissue injury.

16.
ANZ J Surg ; 91(12): 2624-2636, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33825306

RESUMO

BACKGROUND: Lymphoedema is an incurable and progressive disease that affects not only physical function but overall quality of life. Surgical treatment options for the management of lymphoedema are being increasingly performed. This study aims to review post-operative health-related quality of life (HRQOL) following surgical treatment of lymphoedema. METHODS: A systematic search of the PubMed and Medline databases was performed from the date of their inception until September 2018 to evaluate HRQOL following different surgical options for the treatment of lymphoedema. RESULTS: One hundred and thirteen articles were identified. Twenty-one articles were included in the final review, comprising a total of 736 patients. HRQOL improvements appear to be sustained for at least 6-12 months post-operatively. In particular, major benefits were noted in the domains based around physical functioning. Patient satisfaction similarly mirrors HRQOL improvements, following an initial dip in the immediate post-operative period. CONCLUSION: All surgical treatment modalities for the management of lymphoedema confer significant HRQOL improvements across a diverse range of health domains, with this critical outcome of surgery an important pre-operative consideration. Recommendations for ongoing research are suggested.


Assuntos
Linfedema , Qualidade de Vida , Humanos , Linfedema/etiologia , Linfedema/cirurgia
18.
Radiol Res Pract ; 2020: 1403957, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32373363

RESUMO

CT and its comprehensive usage have become one of the most indispensable components in medical field especially in the diagnosis of several diseases. SECT and DECT have developed CT diagnostic potentials in several means. In this review article we have discussed the basic principles of single-energy and dual-energy computed tomography and their important physical differences which can cause better diagnostic evaluation. Moreover, different organs diagnostic evaluations through single-energy and dual-energy computed tomography have been discussed. Conventional or single-energy CT (SECT) uses a single polychromatic X-ray beam (ranging from 70 to 140 kVp with a standard of 120 kVp) emitted from a single source and received by a single detector. The concept of dual-energy computed tomography (DECT) is almost as old as the CT technology itself; DECT initially required substantially higher radiation doses (nearly two times higher than those employed in single-energy CT) and presented problems associated with spatial misregistration of the two different kV image datasets between the two separate acquisitions. The basic principles of single-energy and dual-energy computed tomography and their important physical differences can cause better diagnostic evaluation. Moreover, different organs diagnostic evaluations through single-energy and dual-energy computed tomography have been discussed. According to diverse data and statistics it is controversial to definitely indicate the accurate comparison of image quality and dose amount.

19.
Front Pharmacol ; 11: 158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194404

RESUMO

Fat grafting is a well-established surgical technique used in plastic surgery to restore deficient tissue, and more recently, for its putative regenerative properties. Despite more frequent use of fat grafting, however, a scientific understanding of the mechanisms underlying either survival or remedial benefits of grafted fat remain lacking. Clinical use of fat grafts for breast reconstruction in tissues damaged by radiotherapy first provided clues regarding the clinical potential of stem cells to drive tissue regeneration. Healthy fat introduced into irradiated tissues appeared to reverse radiation injury (fibrosis, scarring, contracture and pain) clinically; a phenomenon since validated in several animal studies. In the quest to explain and enhance these therapeutic effects, adipose-derived stem cells (ADSCs) were suggested as playing a key role and techniques to enrich ADSCs in fat, in turn, followed. Stem cells - the body's rapid response 'road repair crew' - are on standby to combat tissue insults. ADSCs may exert influences either by releasing paracrine-signalling factors alone or as cell-free extracellular vesicles (EVs, exosomes). Alternatively, ADSCs may augment vital immune/inflammatory processes; or themselves differentiate into mature adipose cells to provide the 'building-blocks' for engineered tissue. Regardless, adipose tissue constitutes an ideal source for mesenchymal stem cells for therapeutic application, due to ease of harvest and processing; and a relative abundance of adipose tissue in most patients. Here, we review the clinical applications of fat grafting, ADSC-enhanced fat graft, fat stem cell therapy; and the latest evolution of EVs and nanoparticles in healing, cancer and neurodegenerative and multiorgan disease.

20.
Plast Reconstr Surg Glob Open ; 8(3): e2706, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32537359

RESUMO

Cancer patients often require radiotherapy (RTx) to enhance their survival. Unfortunately, RTx also damages nearby healthy non-cancer tissues, leading to progressive fibrotic soft-tissue injury, consisting of pain, contracture, tissue-breakdown, infection, and lymphoedema. Mechanisms underlying the clinically observed ability of fat grafting to ameliorate some of these effects, however, are poorly understood. It was hypothesized that RTx significantly alters fibroblast cell function and the paracrine secretome of adipose-derived stem cells (ADSC) may mitigate these changes. METHODS: To investigate cellular changes resulting in the fibrotic side-effects of RTx, cultured normal human dermal fibroblasts (NHDF) were irradiated (10Gy), then studied using functional assays that reflect key fibroblast functions, and compared with unirradiated controls. RNA-Seq and targeted microarrays (with specific examination of TGFß) were performed to elucidate altered gene pathways. Finally, conditioned-media from ADSC was used to treat irradiated fibroblasts and model fat graft surgery. RESULTS: RTx altered NHDF morphology, with cellular functional changes reflecting transition into a more invasive phenotype: increased migration, adhesion, contractility, and disordered invasion. Changes in genes regulating collagen and MMP homeostasis and cell-cycle progression were also detected. However, TGFß was not identified as a key intracellular regulator of the fibroblast response. Finally, treatment with ADSC-conditioned media reversed the RTx-induced hypermigratory state of NHDF. CONCLUSIONS: Our findings regarding cellular and molecular changes in irradiated fibroblasts help explain clinical manifestations of debilitating RTx-induced fibrosis. ADSC-secretome-mediated reversal indicated that these constituents may be used to combat the devastating side-effects of excessive unwanted fibrosis in RTx and other human fibrotic diseases.

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