Association of platelet-rich plasma and auto-crosslinked hyaluronic acid microparticles: approach for orthopedic application

Platelet-rich plasma (PRP) associated with high molecular weight hyaluronic acid (HA) has been clinically used for tissue regeneration in orthopedics. Despite the recognized beneficial clinical outcomes (e.g., early pain control, improvement of patients functional limitation and longer-term effectiveness compared to PRP and HA alone in mild and moderate osteoarthritis treatments), its use is still challenging and controversial due to lack of standardization of association practical protocols. Moreover, most studies neglect the matrix structure, that generates the ultimate properties of the association among platelets, fibrin network and the microparticles. In the present work, we aimed to analyze the influence of the PRP/HA association with a controlled matrix structure on the stability, rheological behavior, release of growth factors and in vitro proliferation of human adipose-derived mesenchymal cells (h-AdMSCs). The attenuation of the negative charge of HA was also evaluated. Pure PRP (P-PRP) (i.e., plasma enriched with platelets and poor in leukocytes) was prepared by centrifugation and activated with serum and calcium chloride (AP-PRP). Autocrosslinked hyaluronic acid (AHA) was prepared by organocatalyzed auto-esterification and structured in microparticles (MPAHA) by shearing. The attenuation of the negative charge of MPAHA was performed with chitosan (CHT) by polyelectrolyte complexation yielding MPAHA-CHT. The results showed that microparticles (MPs) have viscoelastic properties, extrusion force and swelling ratio appropriate for injectable applications. The association of AP-PRP with the controlled structure of MPAHA and MPAHA-CHT formed a matrix composed of platelets and of a fibrin network with fibers around 160 nm located preferably on the surface of the MPs with an average diameter of 250 m. Moreover, AP-PRP/MPAHA and AP-PRP/MPAHA-CHT associations were non-toxic and supported controlled growth factor (PDGF-AB and TGF-1) release and in vitro proliferation of h-AdMSC with a similar pattern to that of AP-PRP alone. The best h-AdMSC proliferation was obtained with the AP-PRP/MPAHA-CHT75:25 indicating that the charge attenuation improved the cell proliferation. Thus, the association of AP-PRP with the controlled structure of HA can be a valuable approach for orthopedic applications.This work was supported by the Research Financial Agency FAPESP (Brazil) [grant number 2014/27200-2, 2014] and by the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and co-financed by FEDER, under the Partnership Agreement PT2020 for the project M-ERA-NET/0004/2015-PAIRED and scholarship (SFRH/BD/130555/2017) to Ana Rita Fernandes.info:eu-repo/semantics/publishedVersio

Estudo sobre a contribuição da autópsia como método diagnóstico Study on the contribution of the autopsy as a diagnostic tool

INTRODUÇÃO: As taxas hospitalares de autópsias vêm diminuindo mundialmente, atingindo níveis críticos no Hospital das Clínicas da Universidade Federal de Minas Gerais (HC-UFMG) no que concerne a autópsias não-perinatais. OBJETIVO: Verificar se houve diminuição da relevância da autópsia no HC-UFMG. METODOLOGIA: Realizou-se estudo comparativo entre diagnósticos clínicos e post mortem, estabelecendo taxas de discordância com impacto terapêutico ou prognóstico em duas amostras aleatórias de 80 autópsias realizadas no HC-UFMG nos anos 1970 e outras 80 nos anos 1990, incluindo procedimentos perinatais e não-perinatais. RESULTADOS: Autópsias não-perinatais (adultos e crianças) predominaram na década de 1970. As perinatais (natimortos e neomortos) predominaram na década de 1990, com discordâncias em 56% dos casos. Discordâncias parciais, com correta classificação de malformações congênitas pela autópsia, foram as mais frequentes. Não houve discordâncias na maioria das autópsias de crianças na década de 1970; entretanto, a maioria destas na amostra da década de 1990 revelou discordâncias. Em relação aos adultos, a frequência de erros diagnósticos não apresentou alterações significativas entre as décadas de 1970 (68%) e 1990 (57%). Infecções bacterianas e tromboembolismo pulmonar constituíram frequentes condições não diagnosticadas clinicamente na década de 1970; nos anos 90, os diagnósticos não formulados em vida formaram grupo heterogêneo de doenças. CONCLUSÃO: A autópsia permanece útil como método diagnóstico, apesar de restritamente utilizada na atualidade. É necessária elevação das taxas de autópsias não-perinatas para evitar os efeitos deletérios de sua ausência no ensino, na pesquisa e no controle de qualidade da assistência médica.BACKGROUND: Hospital autopsy rates have declined worldwide and non-perinatal autopsies have reached extremely low numbers at the University Hospital of Federal University of Minas Gerais (HC-UFMG). OBJECTIVES: To determine if there has been a decrease in the relevance of autopsy at HC-UFMG. METHODS: A comparative study between clinical diagnoses and autopsy findings was conducted, establishing discrepancy rates with therapeutic or prognostic impact on two random samples from 80 autopsies performed at HC-UFMG in the mid 1970’s and 80 autopsies in the 1990’s, both including perinatal and non-perinatal procedures. RESULTS: Non-perinatal (adult and pediatric) autopsies predominated in the 1970’s. Perinatal autopsies (stillbirth and neonatal mortality) predominated in the 1990’s, with a discrepancy rate of 56%. Partial discrepancies, with correct classification of congenital malformations by autopsy, were the most frequent. There were no discrepancies in most pediatric autopsies from the 1970’s. However, most pediatric autopsies from the 1990’s revealed discrepancies. As to the adults, the frequency of diagnostic errors did not change significantly from 1970’s (68%) to 1990’s (57%). Bacterial infections and pulmonary embolism were common conditions that were not clinically diagnosed in the 1970’s; in the 1990s, the post mortem diagnoses comprised a heterogeneous group of diseases. CONCLUSION: Autopsies remain as a useful diagnostic tool in spite of its restricted use currently. The rates of non-perinatal autopsies need urgent improving in order to avoid deleterious effects on medical education, research and quality control of medical care

Amnion nodosum and congenital ichthyosis

Made available in DSpace on 2011-11-01T16:37:04Z (GMT). No. of bitstreams: 2 license.txt: 1648 bytes, checksum: e095249ac7cacefbfe39684dfe45e706 (MD5) 1977 - Amnion nodosum na congenital ichthyosis..pdf: 3834427 bytes, checksum: 8c26d2aa1ea42584bb8a3036cf99d3f2 (MD5) Previous issue date: 1977Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Patologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Patologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Patologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Patologia. Rio de Janeiro, RJ, Brasil.Histologic characteristics of the placentas in four cases of amnion nodosum and congenital ichthyosis, a rare association, are presented. Two cases were missed abortions of a single multiparous woman, supporting the hypothesis that in congenital ichthyosis amnion and skin share an abnormal genetic trait. As the amnion showed no hyperkeratosis, it is likely that the amniotic lesions are related to an increased deposition of keratotic plugs on the amnion. Oligohydramnios was verified in two cases; urinary tract malformations were absent in all. The histologic characteristics of the placentas were similar. Noteworthy was the aspect of the chorionic vessels, whose lumens were reduced or obliterated. Perhaps this feature contributed to the poor nutrition of the amnion, a fact assumed by some authors to explain lesions of amnion nodosum. As these vascular alterations are common after fetal death, it is only in the placenta of the newborn that the vascular changes, compatible with rubella vasculitis, may have altered the nutrition of the amnion

Choque séptico puerperal por Streptococcus β-hemolítico e síndrome de Waterhouse-Friderichsen Puerperal septic shock due to β-hemolytic Streptococcus and Waterhouse-Friderichsen syndrome

É relatado caso excepcional de puérpera de 15 anos com choque séptico pelo Streptococcus beta-hemolítico do grupo A e síndrome de Waterhouse-Friderichsen, observado à necropsia. São revistos aspectos do diagnóstico, patogênese e evolução da infecção (sepse) puerperal associada à hemorragia e insuficiência das supra-renais.An exceptional case of a 15-year-old puerpera with septic shock caused by Group A β-hemolytic Streptococcus and Waterhouse-Friderichsen syndrome is reported. The findings were observed at the necropsy. The characteristics of the diagnosis, pathogenesis and evolution of this puerperal infection (sepsis), associated with adrenal hemorrhage and insufficiency are reviewed in this paper

Associação entre a Incisura Diastólica das Artérias Uterinas e a Histologia do Leito Placentário em Grávidas com Pré-eclâmpsia Association between Diastolic Notch of Uterine Artery and the Histology of the Placental Bed in Pregnant Women with Preeclampsia

Objetivo: avaliar a associação entre a presença da incisura diastólica nas artérias uterinas maternas e as alterações histopatológicas dos vasos útero-placentários. Métodos: estudo transversal incluindo 144 pacientes com gestação única interrompida por via abdominal entre a 27ª e a 41ª semana. Destas, 84 gestações estavam associadas à pré-eclâmpsia e 60 não apresentaram intercorrências clínicas. Neste grupo realizou-se dopplerfluxometria de ambas as artérias uterinas e biópsia do leito placentário. Resultados: das 144 pacientes, 88 (61%) tiveram o fragmento da biópsia considerado representativo do leito placentário. A incisura diastólica estava presente em 40 (70%) dos casos de alterações fisiológicas inadequadas e ausente em 28 (90%) dos casos de alterações fisiológicas presentes (p=0,05). A dopplerfluxometria apresentou sensibilidade de 70%, especificidade de 90% e valores preditivos positivo e negativo de 44 e 97%, respectivamente. A associação entre a presença de incisura diastólica bilateral das artérias uterinas e arteriopatia decidual também foi significativa (dos 25 casos de arteriopatia decidual a incisura estava presente em 24, p=0,05). A sensibilidade da dopplerfluxometria foi de 96%, especificidade de 70% e valores preditivos positivo e negativo de 26 e 99%, respectivamente, ao passo que para a arteriolosclerose a dopplerfluxometria apresentou sensibilidade de 80%, especificidade de 55% e valores preditivos positivo e negativo de 17 e 96%, respectivamente. Conclusões: a incisura diastólica nas artérias uterinas maternas é indicador seguro de vasculopatia no leito placentário. A adequada invasão trofoblástica do leito placentário, revelada por histologia típica de alterações fisiológicas, resulta na ausência de incisura diastólica bilateral das artérias uterinas maternas.<br>Purpose: to evaluate the association between the presence of diastolic notch in the maternal uterine arteries, and the histopathological changes of the uteroplacental vessels. Methods: transversal study of 144 women with single pregnancy interrupted by cesarean section between 27 and 41 weeks. In this sample, 84 had pregnancies complicated by preeclampsia and the other 60 were normal. In this group, Doppler study of both uterine arteries and placental bed biopsy was performed. Results: of the total of 144 patients, 88 patients (61%) had a biopsy fragment that was considered representative of the placental bed. The diastolic notch was present in 40 patients (70%) of the total of cases with inadequate physiologic alterations and absent in 28 patients (90%) of the total of cases with physiologic alterations (p=0.0000). The Doppler study showed 70% sensitivity, 90% specificity, 44% positive predictive value and 97% negative predictive value. The association between bilateral diastolic notch of uterine arteries and acute atherosis in the placental bed was also significant (24 out of 25 cases -- p=0.000). The Doppler study showed 96% sensitivity, 70% specificity, 26% positive predictive value and 99% negative predictive value, while for arteriolosclerosis its results were 80% sensitivity, 55% specificity, 17% positive predictive value and 96% negative predictive value. Conclusions: the diastolic notch in the maternal uterine is a safe indicator of pathological vessel alteration in the placental bed. The adequate trophoblast migration into the myometrium, revealed by physiologic changes, results in the absence of bilateral diastolic notch of the maternal uterine arteries

Neonatal Listeriosis: The Importance of Placenta Histological Examination—A Case Report

Neonatal listeriosis is not a rare disease, but it is infrequently diagnosed and reported in the literature. Herein we report a case of listeria lethal sepsis, followed by increased cytokines levels in the cord blood, in which diagnosis was made possible by histological examination of the placenta