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4.
Can J Kidney Health Dis ; 8: 20543581211052185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733538

RESUMO

BACKGROUND: Acute kidney injury (AKI) is a potentially fatal complication of Coronavirus Disease-2019 (COVID-19). Binding of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, to its viral receptor, angiotensin converting enzyme 2 (ACE2), results in viral entry and may cause AKI. OBJECTIVES: We performed a systematic review and meta-analysis of the frequencies of AKI and renal replacement therapy (RRT) in critically ill COVID-19 patients and compared those frequencies with patients who were infected by respiratory viruses that bind or downregulate ACE2 (ACE2-associated viruses) and viruses that do not bind nor downregulate ACE2 (non-ACE2-associated viruses). DESIGN: Systematic review and meta-analysis. SETTING: Observational studies on COVID-19 and other respiratory viral infections reporting AKI and RRT were included. The exclusion criteria were non-English articles, non-peer-reviewed articles, review articles, studies that included patients under the age of 18, studies including fewer than 10 patients, and studies not reporting AKI and RRT rates. PATIENTS: Adult COVID-19, Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and influenza patients. MEASUREMENTS: We extracted the following data from the included studies: author, year, study location, age, sex, race, diabetes mellitus, hypertension, chronic kidney disease, shock, vasopressor use, mortality, intensive care unit (ICU) admission, ICU mortality, AKI, and RRT. METHODS: We systematically searched PubMed and EMBASE for articles reporting AKI or RRT. AKI was defined by authors of included studies. Critical illness was defined by ICU admission. We performed a random effects meta-analysis to calculate pooled estimates for the AKI and RRT rate within each virus group using a random intercept logistic regression model. RESULTS: Of 23 655 hospitalized, critically ill COVID-19 patients, AKI frequencies were not significantly different between COVID-19 patients (51%, 95% confidence interval [CI]: 44%-57%) and critically ill patients infected with ACE2-associated (56%, 95% CI: 37%-74%, P = .610) or non-ACE2-associated viruses (63%, 95% CI: 43%-79%, P = .255). Pooled RRT rates were also not significantly different between critically ill, hospitalized patients with COVID-19 (20%, 95% CI: 16%-24%) and ACE2-associated viruses (18%, 95% CI: 8%-33%, P = .747). RRT rates for both COVID-19 and ACE2-associated viruses were significantly different (P < .001 for both) from non-ACE2-associated viruses (49%, 95% CI: 44%-54%). After adjusting for shock or vasopressor use, AKI and RRT rates were not significantly different between groups. LIMITATIONS: Limitations of this study include the heterogeneity of definitions of AKI that were used across different virus studies. We could not match severity of infection or do propensity matching across studies. Most of the included studies were conducted in retrospective fashion. Last, we did not include non-English publications. CONCLUSIONS: Our findings suggest that viral ACE2 association does not significantly alter the rates of AKI and RRT among critically ill patients admitted to the ICU. However, the rate of RRT is lower in patients with COVID-19 or ACE2-associated viruses when compared with patients infected with non-ACE2-binding viruses, which might partly be due to the lower frequencies of shock and use of vasopressors in these two virus groups. Prospective studies are necessary to demonstrate whether modulation of the ACE2 axis with Renin-Angiotensin System inhibitors impacts the rates of AKI and whether they are beneficial or harmful in COVID-19 patients.


MISE EN CONTEXTE: L'insuffisance rénale aiguë (IRA) est une complication potentiellement mortelle de la maladie à coronavirus-2019 (COVID-19). Obligatoire du Coronavirus 2 du Syndrome Respiratoire Aigu Sévère (SARS-CoV-2), le virus responsable du COVID-19, à son récepteur, l'enzyme de conversion de l'angiotensine 2 (ACE2), entraîne une entrée virale et peut provoquer une IRA. OBJECTIFS DE L'ÉTUDE: Nous avons effectué une revue systématique et une méta-analyse des fréquences de l'IRA et de la thérapie de remplacement renal (RRT) chez les patients COVID-19 gravement malades et a comparé ces fréquences avec les patients qui ont été infectés par des voies respiratoires virus qui lient ou régulent négativement l'ACE2 (virus associés à l'ACE2) et les virus qui ne régulent pas négativement ni ne lient l'ACE2 (virus non associés à l'ACE2). CADRE ET TYPE D'ÉTUDE: Revue systématique et méta-analyse. Des études d'observation sur le COVID-19 et d'autres infections virales respiratoires signalant une AKI et une RRT ont été incluses. Les critères d'exclusion étaient des articles non anglophones, des articles non évalués par des pairs, des articles de revue, des études incluant des patients moins de 18 ans, les études incluant moins de 10 patients et les études ne rapportant pas les taux d'IRA et de RRT. PATIENTS: Adultes COVID-19, syndrome respiratoire aigu sévère (SRAS), syndrome respiratoire du Moyen-Orient (MERS) et malades de la grippe. MESURES: Nous avons extrait les données suivantes des études incluses : auteur, année, lieu de l'étude, âge, sexe, race, diabète sucré, hypertension, maladie rénale chronique, état de choc, utilisation de vasopresseurs, mortalité, admission en unité de soins intensifs (USI), Mortalité en soins intensifs, AKI et RRT. MÉTHODOLOGIE: Nous avons systématiquement recherché dans PubMed et EMBASE les articles rapportant AKI ou RRT. AKI a été défini par les auteurs des études incluses. La maladie grave a été définie par l'admission aux soins intensifs. Nous avons effectué une méta-analyse à effets aléatoires pour calculer estimations regroupées pour le taux d'IRA et de RRT au sein de chaque groupe de virus à l'aide d'un modèle de régression logistique d'interception aléatoire. RÉSULTATS: Sur 23 655 patients hospitalisés et gravement malades COVID-19, les fréquences AKI n'étaient pas significativement différentes entre patients COVID-19 (51 %, intervalle de confiance à 95 % [IC] : 44 %-57 %) et patients gravement malades infectés par l'ACE2 associé (56 %, IC à 95 % : 37 % à 74 %, P = 0,610) ou des virus non associés à l'ACE2 (63 %, IC à 95 % : 43 % à 79 %, P = 0,255). Tarifs RRT groupés n'étaient pas non plus significativement différents entre les patients hospitalisés gravement malades atteints de COVID-19 (20 %, IC à 95 % : 16 % à 24 %) et virus associés à l'ACE2 (18 %, IC à 95 % : 8 % à 33 %, P = 0,747). Taux de RRT pour les virus associés au COVID-19 et à l'ACE2 étaient significativement différents (P < 0,001 pour les deux) des virus non associés à l'ACE2 (49 %, IC à 95 % : 44 % à 54 %). Après ajustement pour le choc ou l'utilisation de vasopresseurs, les taux d'IRA et de RRT n'étaient pas significativement différents entre les groupes. LIMITES DE L'ÉTUDE: Les limites de cette étude incluent l'hétérogénéité des définitions de l'IRA qui ont été utilisées pour différents virus études. Nous n'avons pas pu faire correspondre la gravité de l'infection ou faire une correspondance de propension entre les études. La plupart des études incluses ont été menées de manière rétrospective. Enfin, nous n'avons pas inclus les publications non anglophones. CONCLUSIONS: Nos résultats suggèrent que l'association virale ACE2 ne modifie pas de manière significative les taux d'IRA et de RRT parmi les patients gravement malades admis aux soins intensifs. Cependant, le taux de RRT est plus faible chez les patients atteints de COVID-19 ou associés à l'ACE2 virus par rapport aux patients infectés par des virus ne se liant pas à l'ACE2, ce qui pourrait être dû en partie à la plus faible fréquences de choc et utilisation de vasopresseurs dans ces deux groupes de virus. Des études prospectives sont nécessaires pour démontrer si la modulation de l'axe ACE2 avec les inhibiteurs du système rénine-angiotensine a un impact sur les taux d'IRA et si ells sont bénéfiques ou nocifs chez les patients COVID-19.

5.
Heliyon ; 7(7): e07408, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34296002

RESUMO

Anodised titanium has a long history as a coating structure for implants due to its bioactive and ossified surface, which promotes rapid bone integration. In response to the growing literature on anodised titanium, this article is the first to revisit the evolution of anodised titanium as an implant coating. The review reports the process and mechanisms for the engineering of distinctive anodised titanium structures, the significant factors influencing the mechanisms of its formation, bioactivity, as well as recent pre- and post-surface treatments proposed to improve the performance of anodised titanium. The review then broadens the discussion to include future functional trends of anodised titanium, ranging from the provision of higher surface energy interactions in the design of biocomposite coatings (template stencil interface for mechanical interlock) to techniques for measuring the bone-to-implant contact (BIC), each with their own challenges. Overall, this paper provides up-to-date information on the impacts of the structure and function of anodised titanium as an implant coating in vitro and in/ex vivo tests, as well as the four key future challenges that are important for its clinical translations, namely (i) techniques to enhance the mechanical stability and (ii) testing techniques to measure the mechanical stability of anodised titanium, (iii) real-time/in-situ detection methods for surface reactions, and (iv) cost-effectiveness for anodised titanium and its safety as a bone implant coating.

6.
Heliyon ; 6(4): e03734, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32322726

RESUMO

Additive manufacturing has attracted increasing attention worldwide, especially in the healthcare, biomedical, aerospace, and construction industries. In Malaysia, insufficient acceptance of this technology by local industries has resulted in a call for government and local practitioners to promulgate the development of this technology for various industries, particularly for biomedical products. The current study intends to frame the challenges endured by biomedical industries who use 3D printing technology for their manufacturing processes. Qualitative methods, particularly in-depth interviews, were used to identify the challenges faced by manufacturing firms when producing 3D printed biomedical products. This work was able to identify twelve key challenges when deploying additive manufacturing in biomedical products and these include issues related to binder selection, poor mechanical properties, low-dimensional accuracy, high levels of powder agglomeration, nozzle size, distribution size, limited choice of materials, texture and colour, lifespan of materials, customization of fit and design, layer height, and, lastly, build-failure. Furthermore, there also are six challenges in the management of manufacturing biomedical products using 3D printing technology, and these include staff re-education, product pricing, limited guidelines, cyber-security issues, marketing, and patents and copyright. This study discusses the reality faced by 3D printing players when producing biomedical products in Malaysia, and presents a primary reference for practitioners in other developing countries.

7.
Ultrasound Obstet Gynecol ; 55(1): 15-19, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503365

RESUMO

OBJECTIVE: To evaluate whether elective preterm delivery (ED) at 34 weeks is of postnatal benefit to infants with isolated gastroschisis compared with routine obstetric care (RC). METHODS: Between May 2013 and September 2015, all women with a sonographic diagnosis of fetal gastroschisis referred to a single tertiary center, before 34 weeks' gestation, were invited to participate in this study. Eligible patients were randomized to ED (induction of labor at 34 weeks) or RC (spontaneous labor or delivery by 37-38 weeks, based on standard obstetric indications). The primary outcome measure was length of time on total parenteral nutrition (TPN). Secondary outcomes were time to closure of gastroschisis and length of stay in hospital. Outcome variables were compared using appropriate statistical methods. Analysis was based on intention-to-treat. RESULTS: Twenty-five women were assessed for eligibility, of whom 21 (84%; 95% CI, 63.9-95.5%) agreed to participate in the study; of these, 10 were randomized to ED and 11 to RC. The trial was stopped at the first planned interim analysis due to patient safety concerns and for futility; thus, only 21 of the expected 86 patients (24.4%; 95% CI, 15.8-34.9%) were enrolled. Median gestational age at delivery was 34.3 (range, 34-36) weeks in the ED group and 36.7 (range, 27-38) weeks in the RC group. One patient in the ED group delivered at 36 weeks following unsuccessful induction at 34 weeks. Neonates of women who underwent ED, compared to those in the RC group, showed no difference in the median number of days on TPN (54 (range, 17-248) vs 21 (range, 9-465) days; P = 0.08), number of days to closure of gastroschisis (7 (range, 0-15) vs 5 (range, 0-8) days; P = 0.28) and length of stay in hospital (70.5 (range, 22-137) vs 31 (range, 19-186) days; P = 0.15). However, neonates in the ED group were significantly more likely to experience late-onset sepsis compared with those in the RC group (40% (95% CI, 12.2-73.8%) vs 0%; P = 0.03). CONCLUSION: This study demonstrates no benefit of ED of fetuses with gastroschisis when postnatal gastroschisis management is similar to that used in routine care. Rather, the data suggest that ED is detrimental to infants with gastroschisis. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Parto inducido a las 34 semanas versus atención obstétrica rutinaria en la gastrosquisis fetal: ensayo controlado aleatorizado OBJETIVO: Evaluar si el parto pretérmino inducido (PI) a las 34 semanas es beneficioso para los recién nacidos con gastrosquisis aislada en comparación con la atención obstétrica rutinaria (AR). MÉTODOS: Entre mayo de 2013 y septiembre de 2015, se invitó a participar en este estudio a todas las mujeres con diagnóstico ecográfico de gastrosquisis fetal remitidas a un mismo centro terciario, antes de las 34 semanas de gestación. Las pacientes elegibles fueron asignadas al azar al PI (inducción del parto a las 34 semanas) o a la AR (parto espontáneo a las 37-38 semanas, en función de los indicios obstétricos estándar). La medida de resultado primaria fue la duración de la nutrición parenteral total (NPT). Las medidas de resultado secundarias fueron el tiempo hasta el cierre de la gastrosquisis y la duración de la estancia hospitalaria. Las variables de resultado se compararon mediante métodos estadísticos apropiados. El análisis se basó en la intención de tratar. RESULTADOS: Se evaluó la elegibilidad de 25 mujeres, de las cuales 21 (84%; IC 95%, 63,9-95,5%) aceptaron participar en el estudio; de ellas, 10 fueron asignadas al azar al PI y 11 a la AR. El ensayo se detuvo después del primer análisis provisional planificado debido a preocupaciones sobre la seguridad de las pacientes y por su intrascendencia; por lo tanto, sólo se reclutaron 21 de las 86 pacientes esperadas (24,4%; IC 95%, 15,8-34,9%). La mediana de la edad gestacional en el momento del parto fue de 34,3 (rango: 34-36) semanas en el grupo de PI y 36,7 (rango: 27-38) semanas en el grupo de AR. Una paciente del grupo de PI tuvo un parto a las 36 semanas, después de una inducción infructuosa a las 34 semanas. Los neonatos de las mujeres que se sometieron a PI, comparados con los del grupo de AR, no mostraron diferencias en la mediana del número de días de NPT (54 (rango: 17-248) vs 21 (rango: 9-465) días; P=0,08), número de días hasta el cierre de la gastrosquisis (7 (rango: 0-15) vs 5 (rango: 0-8) días; P=0,28) y duración de la estancia hospitalaria (70,5 (rango: 22-137) vs 31 (rango: 19-186) días; P=0,15). Sin embargo, la probabilidad de experimentar sepsis de inicio tardío fue mayor en los neonatos del grupo de PI en comparación el grupo de AR (40% (IC 95%, 12,2-73,8%) vs 0%; P=0,03). CONCLUSIÓN: Este estudio demuestra que el PI no presenta ningún beneficio para los fetos con gastrosquisis cuando el tratamiento de la gastrosquisis postnatal es similar al utilizado en la atención rutinaria. Más bien, los datos sugieren que el PI es perjudicial para los lactantes con gastrosquisis.


Assuntos
Gastrosquise/diagnóstico , Cuidado Pré-Natal , Parto Obstétrico , Feminino , Gastrosquise/diagnóstico por imagem , Idade Gestacional , Humanos , Gravidez , Resultado do Tratamento , Ultrassonografia Pré-Natal , Adulto Jovem
8.
J Anat ; 236(4): 571-576, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31813164

RESUMO

The structure of the human body and its parts is of obvious relevance in medicine, but it has also played a role in art. Accurate observation of surface or external anatomy is essential in both disciplines, and its understanding has been enhanced by knowledge of what is found beneath the skin, the internal anatomy, usually based on dissection. The role of anatomy in art in general, and in academies of art in particular, is the theme of this paper. The revival of dissection in 14th-century Italy was, if not causative, at least coincidental with the Renaissance. In 1563, Vasari founded the Accademia del Disegno in Florence, with una Anatomia included in its regulations. As a liberal art taught by university graduates, anatomy helped raise the status of painters and sculptors from artisans to artists and from guild to academy. Anatomy teaching was required in subsequent academies in Rome (1593) and Paris (1648), where the pattern of drawing from drawings, from casts, and from life was established and a Professor of Anatomy appointed in 1777. Anatomy was central to two of the Academy's most important genres, history painting and portraiture. The Academy system, with its emphasis on anatomy, spread to other European cities and to the Caribbean and the Americas from the 17th to the 19th centuries. This paper is concerned with the role of anatomy in the founding of art academies in general, while its companion paper, 'A Tale of Two Cities', considers the cases of the academies in London and Dublin in particular.


Assuntos
Anatomia/história , Corpo Humano , Medicina nas Artes/história , Dissecação/história , História do Século XVI , História do Século XVII , História do Século XVIII , Humanos , Itália
9.
J Anat ; 236(4): 577-587, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31835281

RESUMO

Anatomy played a significant role in the establishment of academies in art, initially in Italy and France, and then more widely in Europe and the Americas. This paper considers the role of anatomy in two such academies, the Royal Academy of Arts in London, and the Royal Hibernian Academy of Arts in Dublin. In both cases, anatomy teaching for art students was formalised by the appointment of a Professor of Anatomy, positions that continue to this day. The first Professor of Anatomy in the RA, William Hunter, set the standard by delivering lectures, carrying out dissections and producing écorchés. Some of his successors have published anatomy books specifically for artists, but their enthusiasm has varied. Unlike the continuity of the RA, the RHA has only had bespoke premises from 1826 to 1916, and from 1985 onwards, and its Schools or School have operated from 1826 to 1942, and from 2008 onwards. Anatomy teaching was a casualty of the decline of the formal art academy in the 20th century, but the fortunes of both are reviving in the early 21st century.


Assuntos
Anatomia/história , Corpo Humano , Medicina nas Artes/história , História do Século XIX , Humanos , Irlanda , Itália , Londres
10.
Ultrasound Obstet Gynecol ; 56(4): 532-540, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31709658

RESUMO

OBJECTIVES: We reported previously on an exteriorized-uterus fetoscopic repair for open neural tube defect (ONTD) using a single-layer closure (SLC) technique. However, because SLC was associated with a high rate of cerebrospinal fluid (CSF) leakage at birth, we developed a three-layer closure (3LC) technique comprising a bovine collagen patch, a myofascial layer and a skin layer. The aims of this study were to compare SLC and 3LC in terms of intraoperative, postoperative and obstetric outcomes, as well as short-term neonatal neurologic and non-neurologic outcomes. METHODS: This was a retrospective analysis of prospectively collected data, from 32 consecutive SLC controls and 18 consecutive 3LC cases, that underwent exteriorized-uterus two-port fetoscopic repair of ONTD at our center, between April 2014 and December 2018. All patients satisfied the Management of Myelomeningocele Study (MOMS) criteria. Obstetric, maternal, fetal and early neonatal outcomes were compared between the SLC and 3LC groups. RESULTS: Maternal demographics and mean gestational age (GA) at fetal surgery (25.0 ± 0.7 vs 25.0 ± 0.5 weeks' gestation; P = 0.96), and at delivery (36.5 ± 3.5 vs 37.6 ± 3.0 weeks; P = 0.14), were similar between the SLC and 3LC groups, respectively. The rate of preterm prelabor rupture of membranes (PPROM) < 37 weeks (28% vs 29%; P = 0.9), mean GA at PPROM (32.3 ± 3.4 vs 32.7 ± 1.9 weeks; P = 0.83) and rate of vaginal delivery (50% vs 47%; P = 0.84) were similar for the SLC vs 3LC groups, respectively. In pregnancies that had SLC compared with those that had 3LC, there was a significantly higher incidence of CSF leakage at birth (8/32 (25%) vs 0/17 (0%); P = 0.02) and a significantly lower rate of reversal of hindbrain herniation at 6 weeks postoperatively (18/30 (60%) vs 14/15 (93%); P = 0.02). The rate of infants that met the MOMS criteria for shunt placement or died before 12 months of age (23/31 (74%) vs 7/12 (58%); P = 0.31) and those that required treatment for hydrocephalus by 12 months (15/32 (47%) vs 4/12 (33%); P = 0.42) were similar between the SLC and 3LC groups, respectively. CONCLUSIONS: Compared to SLC, 3LC preserves the fetal and obstetric benefits of fetoscopic repair and shows improved rates of CSF leakage and reversal of hindbrain herniation at 6 weeks postoperatively. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Fetoscopia/métodos , Defeitos do Tubo Neural/cirurgia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/epidemiologia , Técnicas de Fechamento de Ferimentos , Adulto , Vazamento de Líquido Cefalorraquidiano/epidemiologia , Vazamento de Líquido Cefalorraquidiano/etiologia , Feminino , Fetoscopia/efeitos adversos , Humanos , Hidrocefalia/epidemiologia , Hidrocefalia/etiologia , Lactente , Recém-Nascido , Defeitos do Tubo Neural/embriologia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Técnicas de Fechamento de Ferimentos/efeitos adversos
11.
AJNR Am J Neuroradiol ; 40(11): 1954-1959, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31624121

RESUMO

BACKGROUND AND PURPOSE: MR imaging is not routinely used to image the extracranial facial nerve. The purpose of this study was to determine the extent to which this nerve can be visualized with a CISS sequence and to determine the feasibility of using that sequence for locating the nerve relative to tumor. MATERIALS AND METHODS: Thirty-two facial nerves in 16 healthy subjects and 4 facial nerves in 4 subjects with parotid gland tumors were imaged with an axial CISS sequence protocol that included 0.8-mm isotropic voxels on a 3T MR imaging system with a 64-channel head/neck coil. Four observers independently segmented the 32 healthy subject nerves. Segmentations were compared by calculating average Hausdorff distance values and Dice similarity coefficients. RESULTS: The primary bifurcation of the extracranial facial nerve into the superior temporofacial and inferior cervicofacial trunks was visible on all 128 segmentations. The mean of the average Hausdorff distances was 1.2 mm (range, 0.3-4.6 mm). Dice coefficients ranged from 0.40 to 0.82. The relative position of the facial nerve to the tumor could be inferred in all 4 tumor cases. CONCLUSIONS: The facial nerve can be seen on CISS images from the stylomastoid foramen to the temporofacial and cervicofacial trunks, proximal to the parotid plexus. Use of a CISS protocol is feasible in the clinical setting to determine the location of the facial nerve relative to tumor.


Assuntos
Nervo Facial/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Heliyon ; 5(5): e01588, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31080905

RESUMO

Waste materials from natural sources are important resources for extraction and recovery of valuable compounds. Transformation of these waste materials into valuable materials requires specific techniques and approaches. Hydroxyapatite (HAp) is a biomaterial that can be extracted from natural wastes. HAp has been widely used in biomedical applications owing to its excellent bioactivity, high biocompatibility, and excellent osteoconduction characteristics. Thus, HAp is gaining prominence for applications as orthopaedic implants and dental materials. This review summarizes some of the recent methods for extraction of HAp from natural sources including mammalian, aquatic or marine sources, shell sources, plants and algae, and from mineral sources. The extraction methods used to obtain hydroxyapatite are also described. The effect of extraction process and natural waste source on the critical properties of the HAp such as Ca/P ratio, crystallinity and phase assemblage, particle sizes, and morphology are discussed herein.

13.
J Anat ; 234(5): 577-582, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30856275

RESUMO

This paper arose from exhibitions in Oxford and Dublin and comprises three experiments which look at the relationship between anatomy and art. In the first experiment, a passport photograph, photographic portrait and portrait in oils, all of the same sitter, show how artistic input transforms anatomy from a mere likeness into works of art. In the second, the reverse is true, as computer techniques render idealized old master images anatomically accurate. The third experiment addresses the biomechanical consequences of anatomical variation and shows that vehicular design is based on mean body shapes, and so it is the average, rather than the idealized, form that is safer in a collision.


Assuntos
Anatomia Artística , Anatomia , Imagem Corporal , Humanos , Fotografação , Retratos como Assunto
14.
Ultrasound Obstet Gynecol ; 54(6): 752-758, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30640410

RESUMO

OBJECTIVE: Fetal endoscopic tracheal occlusion (FETO) is associated with increased perinatal survival and reduced need for extracorporeal membrane oxygenation (ECMO) in fetuses with severe congenital diaphragmatic hernia (CDH). This study evaluates the impact of FETO on the resolution of pulmonary hypertension (PH) in fetuses with isolated CDH. METHODS: We reviewed retrospectively the medical records of all fetuses evaluated for CDH between January 2004 and July 2017 at a single institution. Fetuses with additional major structural or chromosomal abnormalities were excluded. CDH cases were classified retrospectively into mild, moderate and severe groups based on prenatal magnetic resonance imaging indices (observed-to-expected total fetal lung volume and percentage of intrathoracic liver herniation). Presence of PH was determined based on postnatal echocardiograms. Logistic regression analyses were performed to evaluate the relationship between FETO and resolution of PH by 1 year of age while controlling for side of the CDH, use of ECMO, gestational age at diagnosis, gestational age at delivery, fetal gender, sildenafil use at discharge and CDH severity. Resolution of PH by 1 year of age was compared between a cohort of fetuses with severe CDH that underwent FETO and a cohort that did not have the procedure (non-FETO). A subanalysis was performed restricting the analysis to isolated left CDH. Parametric and non-parametric tests were used for comparisons. RESULTS: Of 257 CDH cases evaluated, 72% (n = 184) had no major structural or chromosomal anomalies of which 58% (n = 107) met the study inclusion criteria. The FETO cohort consisted of 19 CDH cases and the non-FETO cohort (n = 88) consisted of 31 (35%) mild, 32 (36%) moderate and 25 (28%) severe CDH cases. All infants with severe CDH, regardless of whether they underwent FETO, had evidence of neonatal PH. FETO (OR, 3.57; 95% CI, 1.05-12.10; P = 0.041) and ECMO (OR, 5.01; 95% CI, 2.10-11.96; P < 0.001) were independent predictors of resolution of PH by 1 year of age. A higher proportion of infants with severe CDH that underwent FETO had resolution of PH by 1 year after birth compared with infants with severe CDH in the non-FETO cohort (69% (11/16) vs 28% (7/25); P = 0.017). Similar results were observed when the analysis was restricted to cases with left-sided CDH (PH resolution in 69% (11/16) vs 28% (5/18); P = 0.032). CONCLUSION: In infants with severe CDH, FETO and ECMO are independently associated with increased resolution of PH by 1 year of age. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Hérnias Diafragmáticas Congênitas/complicações , Hérnias Diafragmáticas Congênitas/cirurgia , Hipertensão Pulmonar/cirurgia , Traqueia/cirurgia , Ecocardiografia/métodos , Endoscopia/métodos , Oxigenação por Membrana Extracorpórea/normas , Feminino , Fetoscopia/métodos , Idade Gestacional , Hérnias Diafragmáticas Congênitas/classificação , Humanos , Hipertensão Pulmonar/prevenção & controle , Lactente , Fígado/patologia , Medidas de Volume Pulmonar/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Cuidado Pós-Natal/normas , Gravidez , Cuidado Pré-Natal/normas , Estudos Retrospectivos , Índice de Gravidade de Doença , Traqueia/diagnóstico por imagem , Traqueia/embriologia , Resultado do Tratamento
15.
AJNR Am J Neuroradiol ; 39(10): 1903-1906, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30139756

RESUMO

The pointwise encoding time reduction with radial acquisition (PETRA) ultrashort echo time MR imaging sequence at 3T enables visualization of the facial nerve from the brain stem, through the temporal bone, to the stylomastoid foramen without intravenous contrast. Use of the PETRA sequence, or other ultrashort echo time sequences, should be considered in the MR imaging evaluation of certain skull base tumors and perhaps other facial nerve and temporal bone pathologies.


Assuntos
Nervo Facial/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Osso Temporal/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
17.
Exp Eye Res ; 154: 177-189, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27867005

RESUMO

Human retinal ganglion cells (RGCs) derived from pluripotent stem cells (PSCs) have anticipated value for human disease study, drug screening, and therapeutic applications; however, their full potential remains underdeveloped. To characterize RGCs in human embryonic stem cell (hESC) derived retinal organoids we examined RGC markers and surface antigen expression and made comparisons to human fetal retina. RGCs in both tissues exhibited CD184 and CD171 expression and distinct expression patterns of the RGC markers BRN3 and RBPMS. The retinal progenitor cells (RPCs) of retinal organoids expressed CD184, consistent with its expression in the neuroblastic layer in fetal retina. In retinal organoids CD184 expression was enhanced in RGC competent RPCs and high CD184 expression was retained on post-mitotic RGC precursors; CD171 was detected on maturing RGCs. The differential expression timing of CD184 and CD171 permits identification and enrichment of RGCs from retinal organoids at differing maturation states from committed progenitors to differentiating neurons. These observations will facilitate molecular characterization of PSC-derived RGCs during differentiation, critical knowledge for establishing the veracity of these in vitro produced cells. Furthermore, observations made in the retinal organoid model closely parallel those in human fetal retina further validating use of retinal organoid to model early retinal development.


Assuntos
Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Molécula L1 de Adesão de Célula Nervosa/genética , RNA/genética , Receptores CXCR4/genética , Retina/embriologia , Células Ganglionares da Retina/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Células-Tronco Embrionárias/citologia , Humanos , Camundongos , Molécula L1 de Adesão de Célula Nervosa/biossíntese , Organoides/embriologia , Organoides/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/biossíntese , Retina/metabolismo , Células Ganglionares da Retina/citologia , Transdução de Sinais
18.
Ann Oncol ; 27(12): 2275-2283, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27827301

RESUMO

BACKGROUND: Previously, we showed cancer cells rely on the MTH1 protein to prevent incorporation of otherwise deadly oxidised nucleotides into DNA and we developed MTH1 inhibitors which selectively kill cancer cells. Recently, several new and potent inhibitors of MTH1 were demonstrated to be non-toxic to cancer cells, challenging the utility of MTH1 inhibition as a target for cancer treatment. MATERIAL AND METHODS: Human cancer cell lines were exposed in vitro to MTH1 inhibitors or depleted of MTH1 by siRNA or shRNA. 8-oxodG was measured by immunostaining and modified comet assay. Thermal Proteome profiling, proteomics, cellular thermal shift assays, kinase and CEREP panel were used for target engagement, mode of action and selectivity investigations of MTH1 inhibitors. Effect of MTH1 inhibition on tumour growth was explored in BRAF V600E-mutated malignant melanoma patient derived xenograft and human colon cancer SW480 and HCT116 xenograft models. RESULTS: Here, we demonstrate that recently described MTH1 inhibitors, which fail to kill cancer cells, also fail to introduce the toxic oxidized nucleotides into DNA. We also describe a new MTH1 inhibitor TH1579, (Karonudib), an analogue of TH588, which is a potent, selective MTH1 inhibitor with good oral availability and demonstrates excellent pharmacokinetic and anti-cancer properties in vivo. CONCLUSION: We demonstrate that in order to kill cancer cells MTH1 inhibitors must also introduce oxidized nucleotides into DNA. Furthermore, we describe TH1579 as a best-in-class MTH1 inhibitor, which we expect to be useful in order to further validate the MTH1 inhibitor concept.


Assuntos
Enzimas Reparadoras do DNA/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Neoplasias/tratamento farmacológico , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Pirimidinas/administração & dosagem , 8-Hidroxi-2'-Desoxiguanosina , Animais , Linhagem Celular Tumoral , DNA/genética , DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/isolamento & purificação , Desoxiguanosina/metabolismo , Humanos , Camundongos , Neoplasias/genética , Neoplasias/patologia , Nucleotídeos/metabolismo , Oxirredução , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , RNA Interferente Pequeno/genética , Ensaios Antitumorais Modelo de Xenoenxerto
19.
AJNR Am J Neuroradiol ; 37(12): 2396-2399, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27609619

RESUMO

We report percutaneous cryoablation of spine tumors in 7 consecutive patients (5 men, 2 women [mean age, 47 years; range, 17-68 years]) by using intraprocedural image monitoring of ice ball margins to protect adjacent neural elements. Complete tumor ablation was achieved in all patients without neurologic complication. Pain relief was achieved in 4 of 5 (80%) patients; the patient with persistent pain was later found to have enlarging metastases at other sites.


Assuntos
Criocirurgia/métodos , Imagem Multimodal/métodos , Neoplasias da Coluna Vertebral/cirurgia , Adolescente , Adulto , Idoso , Criocirurgia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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