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1.
BMJ Case Rep ; 15(11)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379624

RESUMO

We present an infant with persistent macrocephaly and developmental delay. There is a wide range of differential diagnoses for this presentation, including many rare genetic conditions. Here, a diagnosis of Malan syndrome was made-a rare overgrowth syndrome caused by haploinsufficiency of NFIX and features affecting the neurological and musculoskeletal systems. Improvements in genomic medicine technologies and clinical services have revolutionised the way clinicians diagnose rare diseases. We highlight the importance of early genetic testing, particularly if there are red flag features such as developmental delay, and the need for a coordinated strategy to improve the management of rare diseases like Malan syndrome.


Assuntos
Anormalidades Múltiplas , Deficiência Intelectual , Megalencefalia , Lactente , Humanos , Fatores de Transcrição NFI/genética , Doenças Raras , Megalencefalia/diagnóstico , Megalencefalia/genética , Anormalidades Múltiplas/diagnóstico , Deficiência Intelectual/genética , Diagnóstico Precoce
2.
Frontline Gastroenterol ; 13(e1): e22-e27, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812027

RESUMO

The global incidence and prevalence of paediatric inflammatory bowel disease (IBD) is increasing, with a notable emergence in developing countries with historically low rates. This suggests that environmental and epigenetic factors may play an important role in the pathogenesis and progression of IBD. Epigenetics refers to the study of biological mechanisms that result in a change of phenotype, without an change in the underlying DNA sequence. Epigenetic mechanisms drive many biological processes that occur in health, such as development and ageing, and are also implicated in disease, including cancer and other inflammatory diseases. Importantly, identification of cell-type-specific epigenetic mechanisms could lead to the identification of molecular disease subtypes allowing a personalised treatment approach. In this short review, we provide a summary of epigenetic mechanisms operative in mammals, and their potential involvement in IBD pathogenesis. Furthermore, we discuss key challenges associated with investigating epigenetics in IBD and provide potential strategies to overcome these, such as through the use of 'omics' and organoid technologies.

4.
Cureus ; 13(2): e13294, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33738148

RESUMO

We present the case of a 96-year-old patient treated for severe osteoarthritis with primary total knee arthroplasty (TKA) using a rotational prosthesis. The patient had significant medical comorbidities and her independence was limited due to her severe functional immobility. This case demonstrates that TKA can be a safe procedure with good outcomes in nonagenarians with severe osteoarthritis. Thorough discussion of treatment options is crucial for elderly patients with multiple medical comorbidities. TKA in the nonagenarian population can restore function and independence for patients which may reduce the burden on social care.

5.
Eur Heart J Case Rep ; 4(1): 1-4, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32128497

RESUMO

BACKGROUND: Taxus baccata, also known as English yew, is a poison that causes cardiac arrhythmias and can result in death from cardiogenic shock. CASE SUMMARY: A 49-year-old gentleman was admitted following yew ingestion with suicidal intent. He was bradycardic at 30 b.p.m. and hypotensive on arrival. Electrocardiography revealed complete heart block with broad complex ventricular escape rate of 30 b.p.m. Bedside echocardiography revealed severe global impairment of right and left ventricular systolic function. Urgent temporary transvenous pacing was instituted, and the patient was considered for veno-arterial extracorporeal membrane oxygenation. Unfortunately, he deteriorated rapidly and cardiorespiratory arrest ensued, and despite prolonged in-hospital resuscitation, the patient died. Post-mortem examination revealed small needle-shaped plant leaves together with seeds found in the stomach. Ante mortem serum sample analysis sent to the Royal Botanical Gardens and revealed the presence of taxine Type B alkaloids in the patient's blood. DISCUSSION: Yew poisoning is a rare occurrence, and there is currently no effective antidote. Treatment involves supportive management, comprising prolonged effective cardiopulmonary resuscitation, pacing, and mechanical cardiac support. This case illustrates the importance of prompt recognition of yew poisoning, alongside early consideration of pacing and mechanical cardiac support. Due to the rarity of this cause of heart block, and since patients may not always volunteer a history of yew ingestion, yew poisoning is something that physicians should be aware of and this should be considered in the differential diagnosis in patients with unexpected heart block. Serum analysis for taxine alkaloids can be used to confirm the diagnosis.

6.
BMJ Case Rep ; 20182018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848517

RESUMO

We present a rare case of a 4-year-old boy with newly diagnosed Henöch-Schonlein purpura (HSP) affecting the scrotum and penis. The patient presented to the emergency department with palpable purpura symmetrically distributed over the lower limbs. This was associated with arthritis of the right knee, abdominal pain and scrotal swelling. These symptoms were preceded by an upper respiratory tract infection (URTI). The patient was initially treated with empirical oral antibiotics for epididymitis and was discharged. He subsequently re-presented 12 days later with penile swelling, erythema and tenderness. An ultrasound scan of the penis revealed grossly oedematous subcutaneous tissue with normal penile architecture. His symptoms resolved spontaneously and the patient remains under close follow-up by the paediatric team for further sequelae of HSP.


Assuntos
Doenças dos Genitais Masculinos/etiologia , Vasculite por IgA/complicações , Doenças do Pênis/etiologia , Escroto , Dor Abdominal/etiologia , Pré-Escolar , Diagnóstico Diferencial , Edema/etiologia , Doenças dos Genitais Masculinos/diagnóstico , Humanos , Vasculite por IgA/diagnóstico , Masculino , Doenças do Pênis/diagnóstico
7.
Adv Funct Mater ; 27(39)2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30853878

RESUMO

Unlocking the secrets of the brain is a task fraught with complexity and challenge - not least due to the intricacy of the circuits involved. With advancements in the scale and precision of scientific technologies, we are increasingly equipped to explore how these components interact to produce a vast range of outputs that constitute function and disease. Here, an insight is offered into key areas in which the marriage of neuroscience and nanotechnology has revolutionized the industry. The evolution of ever more sophisticated nanomaterials culminates in network-operant functionalized agents. In turn, these materials contribute to novel diagnostic and therapeutic strategies, including drug delivery, neuroprotection, neural regeneration, neuroimaging and neurosurgery. Further, the entrance of nanotechnology into future research arenas including optogenetics, molecular/ion sensing and monitoring, and piezoelectric effects is discussed. Finally, considerations in nanoneurotoxicity, the main barrier to clinical translation, are reviewed, and direction for future perspectives is provided.

8.
J Plast Reconstr Aesthet Surg ; 69(1): 1-13, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26422652

RESUMO

The rapid ascent of nanotechnology and regenerative therapeutics as applied to medicine and surgery has seen an exponential rise in the scale of research generated in this field. This is evidenced not only by the sheer volume of papers dedicated to nanotechnology but also in a large number of new journals dedicated to nanotechnology and regenerative therapeutics specifically to medicine and surgery. Aspects of nanotechnology that have already brought benefits to these areas include advanced drug delivery platforms, molecular imaging and materials engineering for surgical implants. Particular areas of interest include nerve regeneration, burns and wound care, artificial skin with nanoelectronic sensors and head and neck surgery. This study presents a review of nanotechnology and regenerative therapeutics, with focus on its applications and implications in plastic surgery.


Assuntos
Queimaduras/terapia , Procedimentos de Cirurgia Plástica/métodos , Cirurgia Plástica/métodos , Nanomedicina Teranóstica/métodos , Engenharia Tecidual/métodos , Humanos
9.
Mater Sci Eng C Mater Biol Appl ; 54: 225-38, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26046286

RESUMO

Vascularisation is often deemed the holy grail of tissue engineering because it is one of the key preconditions that determine the in vivo viability of tissue constructs. Given that a well-developed vascular network allows greater complexity in tissue design and helps regulate tissue metabolism, it appears that the overall outcome of engineered tissue implants depends on the success of microvessel formation, maturation and patterning. Current approaches to vascularising tissue include both in vivo and ex vivo techniques, where blood vessel formation is either spontaneous or guided by physical or biochemical factors. The success of these strategies can then be monitored and evaluated for clinical benefit through numerous standard and novel strategies. Despite the impressive progress in the field of tissue engineering in recent times, there are still numerous technical, immunological, surgical and ethical challenges to overcome. Future prospects in this field are likely to depend on the adoption of a wide-ranging approach incorporating a combination of salient themes such as genetic manipulation, modular assembly and bioreactor coupling. Where applicable, the potential contributions of nanobiotechnology to tissue vascularisation will be discussed as appropriate.


Assuntos
Neovascularização Fisiológica , Medicina Regenerativa/métodos , Bioimpressão/métodos , Reatores Biológicos , Técnicas Biossensoriais/instrumentação , Vasos Sanguíneos/fisiologia , Humanos , Nanotecnologia , Próteses e Implantes , Esferoides Celulares/metabolismo , Engenharia Tecidual/métodos , Alicerces Teciduais
10.
Expert Opin Biol Ther ; 15(2): 231-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25427995

RESUMO

INTRODUCTION: Cardiovascular diseases such as coronary heart disease often necessitate the surgical repair using conduits. Although autografts still remain the gold standard, the inconvenience of harvesting and/or insufficient availability in patients with atherosclerotic disease has given impetus to look into alternative sources for vascular grafts. AREAS COVERED: There are four main techniques to produce tissue-engineered vascular grafts (TEVGs): i) biodegradable synthetic scaffolds; ii) gel-based scaffolds; iii) decellularised scaffolds and iv) self-assembled cell-sheet-based techniques. The first three techniques can be grouped together as scaffold-guided approach as it involves the use of a construct to function as a supportive framework for the vascular graft. The most significant advantages of TEVGs are that it possesses the ability to grow, remodel and respond to environmental factors. Cell sources for TEVGs include mature somatic cells, stem cells, adult progenitor cells and pluripotent stem cells. EXPERT OPINION: TEVG holds great promise with advances in nanotechnology, coupled with important refinements in tissue engineering and decellularisation techniques. This will undoubtedly be an important milestone for cardiovascular medicine when it is eventually translated to clinical use.


Assuntos
Prótese Vascular/tendências , Engenharia Tecidual , Implantes Absorvíveis , Animais , Bioprótese/tendências , Doenças Cardiovasculares/terapia , Regeneração Tecidual Guiada/instrumentação , Regeneração Tecidual Guiada/métodos , Humanos , Polímeros/química , Polímeros/uso terapêutico , Células-Tronco/citologia , Células-Tronco/fisiologia , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências , Alicerces Teciduais , Transplante Autólogo
11.
Transl Oncol ; 7(6): 657-64, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25500073

RESUMO

With greater technological advancements and understanding of pathophysiology, "personalized medicine" has become a more realistic goal. In the field of cancer, personalized medicine is the ultimate objective, as each cancer is unique and each tumor is heterogeneous. For many decades, researchers have relied upon studying the histopathology of tumors in the hope that it would provide clues to understanding the pathophysiology of cancer. Current preclinical research relies heavily upon two-dimensional culture models. However, these models have had limited success in recreating the complex interactions between cancer cells and the stroma environment in vivo. Thus, there is increasing impetus to shift to three-dimensional models, which more accurately reflect this phenomenon. With a more accurate in vitro tumor model, drug sensitivity can be tested to determine the best treatment option based on the tumor characteristics. Many methods have been developed to create tumor models or "tumoroids," each with its advantages and limitations. One significant problem faced is the replication of angiogenesis that is characteristic of tumors in vivo. Nonetheless, if three-dimensional models could be standardized and implemented as a preclinical research tool for therapeutic testing, we would be taking a step towards making personalized cancer medicine a reality.

12.
PLoS One ; 8(10): e77112, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24116210

RESUMO

In situ endothelialization of cardiovascular implants has emerged in recent years as an attractive means of targeting the persistent problems of thrombosis and intimal hyperplasia. This study aimed to investigate the efficacy of immobilizing anti-CD34 antibodies onto a POSS-PCU nanocomposite polymer surface to sequester endothelial progenitor cells (EPCs) from human blood, and to characterize the surface properties and hemocompatibility of this surface. Amine-functionalized fumed silica was used to covalently conjugate anti-CD34 to the polymer surface. Water contact angle, fluorescence microscopy, and scanning electron microscopy were used for surface characterization. Peripheral blood mononuclear cells (PBMCs) were seeded on modified and pristine POSS-PCU polymer films. After 7 days, adhered cells were immunostained for the expression of EPC and endothelial cell markers, and assessed for the formation of EPC colonies. Hemocompatibility was assessed by thromboelastography, and platelet activation and adhesion assays. The number of EPC colonies formed on anti-CD34-coated POSS-PCU surfaces was not significantly higher than that of POSS-PCU (5.0±1.0 vs. 1.7±0.6, p>0.05). However, antibody conjugation significantly improved hemocompatibility, as seen from the prolonged reaction and clotting times, decreased angle and maximum amplitude (p<0.05), as well as decreased platelet adhesion (76.8±7.8 vs. 8.4±0.7, p<0.05) and activation. Here, we demonstrate that POSS-PCU surface immobilized anti-CD34 antibodies selectively captured CD34+ cells from peripheral blood, although only a minority of these were EPCs. Nevertheless, antibody conjugation significantly improves the hemocompatibility of POSS-PCU, and should therefore continue to be explored in combination with other strategies to improve the specificity of EPC capture to promote in situ endothelialization.


Assuntos
Anticorpos Imobilizados/imunologia , Antígenos CD34/imunologia , Materiais Revestidos Biocompatíveis/química , Nanocompostos/química , Compostos de Organossilício/química , Poliuretanos/química , Stents , Anticorpos Imobilizados/química , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/imunologia , Humanos , Teste de Materiais , Ativação Plaquetária , Adesividade Plaquetária , Células-Tronco/citologia , Células-Tronco/imunologia
13.
N Biotechnol ; 30(5): 461-74, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23664865

RESUMO

The advent of optogenetics provides a new direction for the field of neuroscience and biotechnology, serving both as a refined investigative tool and as potential cure for many medical conditions via genetic manipulation. Although still in its infancy, recent advances in optogenetics has made it possible to remotely manipulate in vivo cellular functions using light. Coined Nature Methods' 'Method of the Year' in 2010, the optogenetic toolbox has the potential to control cell, tissue and even animal behaviour. This optogenetic toolbox consists of light-sensitive proteins that are able to modulate membrane potential in response to light. Channelrhodopsins (ChR) are light-gated microbial ion channels, which were first described in green algae. ChR2 (a subset of ChR) is a seven transmembrane α helix protein, which evokes membrane depolarization and mediates an action potential upon photostimulation with blue (470 nm) light. By contrast to other seven-transmembrane proteins that require second messengers to open ion channels, ChR2 form ion channels themselves, allowing ultrafast depolarization (within 50 milliseconds of illumination). It has been shown that integration of ChR2 into various tissues of mice can activate neural circuits, control heart muscle contractions, and even restore breathing after spinal cord injury. More compellingly, a plethora of evidence has indicated that artificial expression of ChR2 in retinal ganglion cells can reinstate visual perception in mice with retinal degeneration.


Assuntos
Potenciais da Membrana , Regeneração , Degeneração Retiniana/terapia , Células Ganglionares da Retina/metabolismo , Transmissão Sináptica , Visão Ocular , Animais , Channelrhodopsins , Humanos , Luz , Camundongos , Camundongos Transgênicos , Contração Miocárdica/genética , Miocárdio/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células Ganglionares da Retina/patologia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
14.
Biointerphases ; 8(1): 23, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24706135

RESUMO

An unmet need exists for the development of next-generation multifunctional nanocomposite materials for biomedical applications, particularly in the field of cardiovascular regenerative biology. Herein, we describe the preparation and characterization of a novel polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer with covalently attached anti-CD34 antibodies to enhance capture of circulating endothelial progenitor cells (EPC). This material may be used as a new coating for bare metal stents used after balloon angioplasty to improve re-endothelialization. Biophysical characterization techniques were used to assess POSS-PCU and its subsequent functionalization with anti-CD34 antibodies. Results indicated successful covalent attachment of anti-CD34 antibodies on the surface of POSS-PCU leading to an increased propensity for EPC capture, whilst maintaining in vitro biocompatibility and hemocompatibility. POSS-PCU has already been used in 3 first-in-man studies, as a bypass graft, lacrimal duct and a bioartificial trachea. We therefore postulate that its superior biocompatibility and unique biophysical properties would render it an ideal candidate for coating medical devices, with stents as a prime example. Taken together, anti-CD34 functionalized POSS-PCU could form the basis of a nano-inspired polymer platform for the next generation stent coatings.


Assuntos
Células Progenitoras Endoteliais/fisiologia , Nanocompostos/química , Compostos de Organossilício/química , Polímeros/química , Poliuretanos/química , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Polímeros/farmacologia
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