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1.
Cells ; 12(24)2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38132170

RESUMO

Osteoarthritis (OA) most frequently affects the knee joint and is associated with an elevated expression of cytokines and extracellular cartilage matrix (ECM), degrading enzymes such as matrix metalloproteinases (MMPs). Differences in gene expression of the intra-articularly located infrapatellar fat pad (IPFP) and other fatty tissue suggest its autonomous function, yet its role in OA pathogenesis remains unknown. Human IPFPs and articular cartilage were collected from OA patients undergoing total knee arthroplasty, and biopsies from the IPFP of healthy patients harvested during knee arthroscopy served as controls (CO). Isolated chondrocytes were co-cultured with either osteoarthritic (OA) or CO-IPFPs in a transwell system. Chondrocyte expression of MMP1, -3, -13, type 1 and 2 collagens, interleukin IL1ß, IL6, IL10, and tumor necrosis factor TNFα was analyzed by RTD-PCR at day 0 and day 2, and TNFα secretion was analyzed by ELISA. The cytokine release in IPFPs was assessed by an array. Results: Both IPFPs (CO, OA) significantly reduced the expression of type 2 collagen and TNFα in chondrocytes. On the other hand, only CO-IPFP suppressed the expression of type 1 collagen and significantly induced the MMP13 expression. On the contrary, IL1ß and IL6 were significantly induced when exposed to OA-IPFP. Conclusions: The partial loss of the suppressive effect on type 1 collagen gene expression found for OA-IPFP shows the pathological remodeling and dedifferentiation potential of the OA-IPFP on the chondrocytes. However, the significant suppression of TNFα implies that the OA- and CO-IPFP could also exhibit a protective role in the knee joint, preventing the progress of inflammation.


Assuntos
Citocinas , Osteoartrite do Joelho , Humanos , Citocinas/metabolismo , Condrócitos/metabolismo , Osteoartrite do Joelho/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Colágeno Tipo I/metabolismo , Articulação do Joelho/patologia , Tecido Adiposo/metabolismo
2.
Nutrients ; 15(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37447201

RESUMO

Intervertebral disc (IVD) degeneration is a common cause of low back pain in diabetes mellitus type 2 (T2DM) patients. Its pathogenesis and the vitamin (vit.) K2 influence on this disease remain unclear. Lumbar motion segments of male Zucker Diabetes Fatty (ZDF) rats (non-diabetic [control] and diabetic; fed without or with vit. K2) were used. Femur lengths and vertebral epiphyseal cross-section areas were measured. IVDs were histopathologically examined. Protein synthesis and gene expression of isolated IVD fibrochondrocytes were analyzed. T2DM rats showed histopathological IVD degeneration. Femur lengths and epiphyseal areas were smaller in T2DM rats regardless of vit. K2 feeding. Fibrochondrocytes synthesized interleukin (IL)-24 and IL-10 with no major differences between groups. Alpha smooth muscle actin (αSMA) was strongly expressed, especially in cells of vit. K2-treated animals. Gene expression of aggrecan was low, and that of collagen type 2 was high in IVD cells of diabetic animals, whether treated with vit. K2 or not. Suppressor of cytokine signaling (Socs)3 and heme oxygenase (Hmox)1 gene expression was highest in the cells of diabetic animals treated with vit. K2. Vit. K2 influenced the expression of some stress-associated markers in IVD cells of diabetic rats, but not that of IL-10 and IL-24.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Degeneração do Disco Intervertebral , Disco Intervertebral , Ratos , Masculino , Animais , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Vitamina K 2/metabolismo , Interleucina-10/metabolismo , Diabetes Mellitus Experimental/metabolismo , Ratos Zucker , Diabetes Mellitus Tipo 2/metabolismo
3.
Histochem Cell Biol ; 159(3): 275-292, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36309635

RESUMO

Although autografts represent the gold standard for anterior cruciate ligament (ACL) reconstruction, tissue-engineered ACLs provide a prospect to minimize donor site morbidity and limited graft availability. This study characterizes the ligamentogenesis in embroidered poly(L-lactide-co-ε-caprolactone) (P(LA-CL)) / polylactic acid (PLA) constructs using a dynamic nude mice xenograft model. (P(LA-CL))/PLA scaffolds remained either untreated (co) or were functionalized by gas fluorination (F), collagen foam cross-linked with hexamethylene diisocyanate (HMDI) (coll), or F combined with the foam (F + coll). Cell-free constructs or those seeded for 1 week with lapine ACL ligamentocytes were implanted into nude mice for 12 weeks. Following explantation, cell vitality and content, histo(patho)logy of scaffolds (including organs: liver, kidney, spleen), sulphated glycosaminoglycan (sGAG) contents and biomechanical properties were assessed.Scaffolds did not affect mice weight development and organs, indicating no organ toxicity. Moreover, scaffolds maintained their size and shape and reflected a high cell viability prior to and following implantation. Coll or F + coll scaffolds seeded with cells yielded superior macroscopic properties compared to the controls. Mild signs of inflammation (foreign-body giant cells and hyperemia) were limited to scaffolds without collagen. Microscopical score values and sGAG content did not differ significantly. Although remaining stable after explantation, elastic modulus, maximum force, tensile strength and strain at Fmax were significantly lower in explanted scaffolds compared to those before implantation, with no significant differences between scaffold subtypes, except for a higher maximum force in F + coll compared with F samples (in vivo). Scaffold functionalization with fluorinated collagen foam provides a promising approach for ACL tissue engineering. a Lapine anterior cruciate ligament (LACL): red arrow, posterior cruciate ligament: yellow arrow. Medial anterior meniscotibial ligament: black arrow. b Explant culture to isolate LACL fibroblasts. c Scaffold variants: co: controls; F: functionalization by gas-phase fluorination; coll: collagen foam cross-linked with hexamethylene diisocyanate (HMDI). c1-2 Embroidery pattern of the scaffolds. d Scaffolds were seeded with LACL fibroblasts using a dynamical culturing approach as depicted. e Scaffolds were implanted subnuchally into nude mice, fixed at the nuchal ligament and sacrospinal muscle tendons. f Two weeks after implantation. g Summary of analyses performed. Scale bars 1 cm (b, d), 0.5 cm (c). (sketches drawn by G.S.-T. using Krita 4.1.7 [Krita foundation, The Netherlands]).


Assuntos
Colágeno , Halogenação , Humanos , Camundongos , Animais , Camundongos Nus , Engenharia Tecidual/métodos , Poliésteres
4.
BMC Anesthesiol ; 21(1): 189, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246222

RESUMO

BACKGROUND: Cardiac output (CO) is a key measure of adequacy of organ and tissue perfusion, especially in critically ill or complex surgical patients. CO monitoring technology continues to evolve. Recently developed CO monitors rely on unique algorithms based on pulse contour analysis of an arterial blood pressure (ABP) waveform. The objective of this investigation was to compare the accuracy of two monitors using different methods of pulse contour analysis - the Retia Argos device and the Edwards Vigileo-FloTrac device - with pulmonary artery catheter (PAC)-thermodilution as a reference. METHODS: Fifty-eight patients undergoing off-pump coronary artery bypass surgery formed the study cohort. A total of 572 triplets of CO measurements from each device - Argos, Vigileo-FloTrac (third generation), and thermodilution - were available before and after interventions (e.g., vasopressors, fluids, and inotropes). Bland-Altman analysis accounting for repeated measurements per subject and concordance analysis were applied to assess the accuracy of the CO values and intervention-induced CO changes of each pulse contour device against thermodilution. Cluster bootstrapping was employed to statistically compare the root-mean-squared-errors (RMSE = √(µ2 + σ2), where µ and σ are the Bland-Altman bias and precision errors) and concordance rates of the two devices. RESULTS: The RMSE (mean (95% confidence intervals)) for CO values was 1.16 (1.00-1.32) L/min for the Argos device and 1.54 (1.33-1.77) L/min for the Vigileo-FloTrac device; the concordance rate for intervention-induced CO changes was 87 (82-92)% for the Argos device and 72 (65-78)% for the Vigileo-FloTrac device; and the RMSE for the CO changes was 17 (15-19)% for the Argos device and 21 (19-23)% for the Vigileo-FloTrac device (p < 0.0167 for all comparisons). CONCLUSIONS: In comparison with CO measured by the PAC, the Argos device proved to be more accurate than the Vigileo-FloTrac device in CO trending and absolute CO measurement in patients undergoing off-pump coronary artery bypass surgery.


Assuntos
Débito Cardíaco/fisiologia , Ponte de Artéria Coronária sem Circulação Extracorpórea/métodos , Monitorização Intraoperatória/métodos , Termodiluição/métodos , Idoso , Pressão Arterial/fisiologia , Cateterismo de Swan-Ganz/métodos , Estudos de Coortes , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação
5.
J Clin Med Res ; 13(3): 184-190, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33854659

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) mortality has waned significantly over time; however, factors contributing towards this reduction largely remain unidentified. The purpose of this study was to evaluate the trend in mortality at our large tertiary academic health system and factors contributing to this trend. METHODS: This is a retrospective cohort study of intensive care unit (ICU) patients diagnosed with COVID-19 between March and August 2020 admitted across 14 hospitals in the Philadelphia area. Collected data included demographics, comorbidities, admission risk of mortality score, laboratory values, medical interventions, survival outcomes, hospital and ICU length of stay (LOS) and discharge disposition. Chi-square (χ2) test, Fisher exact test, Cochran-Mantel-Haenszel method, multinomial logistic regression models, independent sample t-test, Mann-Whitney U test and one-way analysis of variance (ANOVA) were used. RESULTS: A total of 1,204 patients were included. Overall mortality was 39%. Mortality declined significantly from 46% in March to 14% in August 2020 (P < 0.05). The most common underlying comorbidities were hypertension (60.2%), diabetes mellitus (44.7%), dyslipidemia (31.6%) and congestive heart failure (14.7%). Hydroxychloroquine (HCQ) use was more commonly associated with the patients who died, while the use of remdesivir, tocilizumab, steroids and duration of these medications were not significantly different. Peak values of ferritin, lactate dehydrogenase (LDH), C-reactive protein (CRP) and D-dimer levels were significantly higher in patients who died (P < 0.05). The mean hospital LOS was significantly longer in the patients who survived compared to the patients who died (18 vs. 12, P < 0.05). CONCLUSIONS: The mortality of patients admitted to our ICU system significantly decreased over time. Factors that may have contributed to this may be the result of a better understanding of COVID-19 pathophysiology and treatments. Further research is needed to elucidate the factors contributing to a reduction in the mortality rate for this patient population.

6.
Int J Mol Sci ; 22(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803624

RESUMO

A central part of the complement system, the anaphylatoxin C5a was investigated in this study to learn its effects on tenocytes in respect to understanding the potential expression of other crucial complement factors and pro-inflammatory mediators involved in tendinopathy. Human hamstring tendon-derived tenocytes were treated with recombinant C5a protein in concentrations of 25 ng/mL and 100 ng/mL for 0.5 h (early phase), 4 h (intermediate phase), and 24 h (late phase). Tenocytes survival was assessed after 24 h stimulation by live-dead assay. The gene expression of complement-related factors C5aR, the complement regulatory proteins (CRPs) CD46, CD55, CD59, and of the pro-inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 was monitored using qPCR. Tenocytes were immunolabeled for C5aR and CD55 proteins. TNFα production was monitored by ELISA. Tenocyte survival was not impaired through C5a stimulation. Interestingly, the gene expression of C5aR and that of the CRPs CD46 and CD59 was significantly reduced in the intermediate and late phase, and that of TNFα only in an early phase, compared to the control group. ELISA analysis indicated a concomitant not significant trend of impaired TNFα protein synthesis at 4 h. However, there was also an early significant induction of CD55 and CD59 mediated by 25 ng/mL anaphylatoxin C5a. Hence, exposure of tenocytes to C5a obviously evokes a time and concentration-dependent response in their expression of complement and pro-inflammatory factors. C5a, released in damaged tendons, might directly contribute to tenocyte activation and thereby be involved in tendon healing and tendinopathy.


Assuntos
Complemento C5a/metabolismo , Proteínas do Sistema Complemento/metabolismo , Tenócitos/metabolismo , Adulto , Antígenos CD55/metabolismo , Ativação do Complemento , Regulação da Expressão Gênica , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Receptor da Anafilatoxina C5a/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
Inflamm Res ; 70(4): 495-507, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33772629

RESUMO

INTRODUCTION: The present in vitro study was undertaken to learn about the effects of leukocytes on tenocytes in respect to complement regulation simulating an inflammatory scenario of the traumatized tissue. METHODS: Human hamstring tendon-derived tenocyte monolayers were co-cultured indirectly with human leukocytes (either Peripheral Blood Mononuclear Cells [PBMCs] or neutrophils) using a transwell system with/without (+ /wo) 10 ng/ml tumor necrosis factor α (TNFα) for 4 and 24 h. Tenocyte and leukocyte cell survival was assessed by live-dead assay. Tenocyte gene expression of TNFα, the anaphylatoxin receptor C5aR and the cytoprotective complement regulatory proteins (CRP) CD46, CD55 and CD59 was monitored using qPCR. TNFα was detected in the culture supernatants using ELISA. RESULTS: C5aR gene expression was significantly induced by TNFα after 4 h, but impaired in the presence of leukocytes + TNFα after 24 h. At 4 h, PBMCs activated by TNFα induced the CRP CD46 gene expression. However, CD55 was significantly suppressed after 24 h by neutrophils + /woTNFα. Leukocytes activated by TNFα decreased also significantly the gene expression of the more downstream acting CRP CD59 after 4 h. TNFα gene expression and ELISA analysis revealed an amplified TNFα expression/release in tenocyte co-cultures with PBMC + /woTNFα, probably contributing to complement regulation. CONCLUSION: TNFα might represent a crucial soluble mediator exerting diverse time-dependent effects on tenocyte complement regulation.


Assuntos
Antígenos CD/metabolismo , Leucócitos Mononucleares/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Tenócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Antígenos CD/genética , Células Cultivadas , Técnicas de Cocultura , Proteínas do Sistema Complemento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptor da Anafilatoxina C5a/genética , Fator de Necrose Tumoral alfa/genética
8.
Int J Mol Sci ; 21(12)2020 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-32545914

RESUMO

Tendinopathy is a rare but serious complication of quinolone therapy. Risk factors associated with quinolone-induced tendon disorders include chronic kidney disease accompanied by the accumulation of uremic toxins. Hence, the present study explored the effects of the representative uremic toxins phenylacetic acid (PAA) and quinolinic acid (QA), both alone and in combination with ciprofloxacin (CPX), on human tenocytes in vitro. Tenocytes incubated with uremic toxins +/- CPX were investigated for metabolic activity, vitality, expression of the dominant extracellular tendon matrix (ECM) protein type I collagen, cell-matrix receptor ß1-integrin, proinflammatory interleukin (IL)-1ß, and the ECM-degrading enzyme matrix metalloproteinase (MMP)-1. CPX, when administered at high concentrations (100 mM), suppressed tenocyte metabolism after 8 h exposure and at therapeutic concentrations after 72 h exposure. PAA reduced tenocyte metabolism only after 72 h exposure to very high doses and when combined with CPX. QA, when administered alone, led to scarcely any cytotoxic effect. Combinations of CPX with PAA or QA did not cause greater cytotoxicity than incubation with CPX alone. Gene expression of the pro-inflammatory cytokine IL-1ß was reduced by CPX but up-regulated by PAA and QA. Protein levels of type I collagen decreased in response to high CPX doses, whereas PAA and QA did not affect its synthesis significantly. MMP-1 mRNA levels were increased by CPX. This effect became more pronounced in the form of a synergism following exposure to a combination of CPX and PAA. CPX was more tenotoxic than the uremic toxins PAA and QA, which showed only distinct suppressive effects.


Assuntos
Ciprofloxacina/efeitos adversos , Interleucina-1beta/genética , Fenilacetatos/efeitos adversos , Ácido Quinolínico/efeitos adversos , Tenócitos/citologia , Adulto , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Metaloproteinase 1 da Matriz/genética , Tenócitos/efeitos dos fármacos , Tenócitos/metabolismo
9.
Int J Mol Sci ; 21(6)2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245213

RESUMO

Intervertebral disc (IVD) herniation and degeneration is a major source of back pain. In order to regenerate a herniated and degenerated disc, closure of the anulus fibrosus (AF) is of crucial importance. For molecular characterization of AF, genome-wide Affymetrix HG-U133plus2.0 microarrays of native AF and cultured cells were investigated. To evaluate if cells derived from degenerated AF are able to initiate gene expression of a regenerative pattern of extracellular matrix (ECM) molecules, cultivated cells were stimulated with bone morphogenetic protein 2 (BMP2), transforming growth factor ß1 (TGFß1) or tumor necrosis factor-α (TNFα) for 24 h. Comparative microarray analysis of native AF tissues showed 788 genes with a significantly different gene expression with 213 genes more highly expressed in mild and 575 genes in severe degenerated AF tissue. Mild degenerated native AF tissues showed a higher gene expression of common cartilage ECM genes, whereas severe degenerated AF tissues expressed genes known from degenerative processes, including matrix metalloproteinases (MMP) and bone associated genes. During monolayer cultivation, only 164 differentially expressed genes were found. The cells dedifferentiated and altered their gene expression profile. RTD-PCR analyses of BMP2- and TGFß1-stimulated cells from mild and severe degenerated AF tissue after 24 h showed an increased expression of cartilage associated genes. TNFα stimulation increased MMP1, 3, and 13 expression. Cells derived from mild and severe degenerated tissues could be stimulated to a comparable extent. These results give hope that regeneration of mildly but also strongly degenerated disc tissue is possible.


Assuntos
Anel Fibroso/metabolismo , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/genética , Degeneração do Disco Intervertebral/metabolismo , Deslocamento do Disco Intervertebral/metabolismo , Disco Intervertebral/metabolismo , Anel Fibroso/patologia , Proteína Morfogenética Óssea 2/farmacologia , Células Cultivadas , Matriz Extracelular/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/genética , Deslocamento do Disco Intervertebral/patologia , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Regeneração/efeitos dos fármacos , Regeneração/genética , Fator de Crescimento Transformador beta1/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
11.
Int J Mol Sci ; 21(2)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31963350

RESUMO

Cultured human primary cells have a limited lifespan undergoing dedifferentiation or senescence. Anterior cruciate ligaments (ACL) are hypocellular but tissue engineering (TE) requires high cell numbers. Simian virus (SV) 40 tumor (T) antigen expression could extend the lifespan of cells. This study aimed to identify cellular changes induced by SV40 expression in human ACL ligamentocytes by comparing them with non-transfected ligamentocytes and tissue of the same donor to assess their applicability as TE model. Human ACL ligamentocytes (40-year-old female donor after ACL rupture) were either transfected with a SV40 plasmid or remained non-transfected (control) before monitored for SV40 expression, survival, and DNA content. Protein expression of cultured ligamentocytes was compared with the donor tissue. Ligamentocyte spheroids were seeded on scaffolds embroidered either from polylactic acid (PLA) threads solely or combined PLA and poly (L-lactide-co-ε-caprolactone) (P(LA-CL)) threads. These scaffolds were further functionalized with fluorination and fibrillated collagen foam. Cell distribution and survival were monitored for up to five weeks. The transfected cells expressed the SV40 antigen throughout the entire observation time, but often exhibited random and incomplete cell divisions with significantly more dying cells, significantly more DNA and more numerous nucleoli than controls. The expression profile of non-transfected and SV40-positive ligamentocytes was similar. In contrast to controls, SV40-positive cells formed larger spheroids, produced less vimentin and focal adhesions and died on the scaffolds after 21 d. Functionalized scaffolds supported human ligamentocyte growth. SV40 antigen expressing ligamentocytes share many properties with their non-transfected counterparts suggesting them as a model, however, applicability for TE is limited.


Assuntos
Ligamento Cruzado Anterior/citologia , Ligamento Cruzado Anterior/metabolismo , Engenharia Tecidual/métodos , Humanos , Poliésteres/química , Alicerces Teciduais/química
12.
Am J Emerg Med ; 38(3): 692.e1-692.e3, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31785982

RESUMO

Caffeine is the most commonly used central nervous system stimulant. While it has a high LD50 (150-200 mg/kg), when ingested in significant quantity, caffeine can lead to severe and even lethal side effects. Manifestation of toxicity include tachyarrhythmias, seizures, and metabolic derangements which can eventually lead to cardiovascular collapse and death. Studies have shown that lethal doses of caffeine (80-100 µg/mL) can be seen with the ingestion of approximately 10 g of caffeine. Due to the low number of reported cases, there is no consensus on the standard of care for treatment of suspected caffeine overdose. This case details a 39-year-old male who presented to the emergency department (ED) after having ingested 50 g of caffeine. Despite a high dose esmolol infusion, the patient exhibited worsening tachyarrhythmias. Hemodialysis was started empirically given the known amount ingested and ongoing hemodynamic perturbations. Initial pre-dialysis caffeine level was found to be 254 µg/ml. After treatment with two sessions of hemodialysis the patient's caffeine level decreased dramatically. We believe this is the first case report to demonstrate the success of preemptive hemodialysis, prior to cardiovascular collapse and/or renal failure, in a case of caffeine overdose and should be considered very early in patients presenting with recent toxic ingestion.


Assuntos
Cafeína/efeitos adversos , Overdose de Drogas/cirurgia , Diálise Renal/métodos , Tentativa de Suicídio , Doença Aguda , Adulto , Estimulantes do Sistema Nervoso Central/efeitos adversos , Overdose de Drogas/etiologia , Overdose de Drogas/terapia , Humanos , Masculino
13.
PeerJ ; 7: e7053, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367478

RESUMO

Muscle fibre cross-sectional area (CSA) is an important biomedical measure used to determine the structural composition of skeletal muscle, and it is relevant for tackling research questions in many different fields of research. To date, time consuming and tedious manual delineation of muscle fibres is often used to determine the CSA. Few methods are able to automatically detect muscle fibres in muscle fibre cross-sections to quantify CSA due to challenges posed by variation of brightness and noise in the staining images. In this paper, we introduce the supervised learning-computer vision combined pipeline (SLCV), a robust semi-automatic pipeline for muscle fibre detection, which combines supervised learning (SL) with computer vision (CV). SLCV is adaptable to different staining methods and is quickly and intuitively tunable by the user. We are the first to perform an error analysis with respect to cell count and area, based on which we compare SLCV to the best purely CV-based pipeline in order to identify the contribution of SL and CV steps to muscle fibre detection. Our results obtained on 27 fluorescence-stained cross-sectional images of varying staining quality suggest that combining SL and CV performs significantly better than both SL-based and CV-based methods with regards to both the cell separation- and the area reconstruction error. Furthermore, applying SLCV to our test set images yielded fibre detection results of very high quality, with average sensitivity values of 0.93 or higher on different cluster sizes and an average Dice similarity coefficient of 0.9778.

14.
PLoS One ; 14(4): e0213734, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973882

RESUMO

Osteoarthritis (OA) is the most common cause of disability in ageing societies, with no effective therapies available to date. Two preclinical models are widely used to validate novel OA interventions (MCL-MM and DMM). Our aim is to discern disease dynamics in these models to provide a clear timeline in which various pathological changes occur. OA was surgically induced in mice by destabilisation of the medial meniscus. Analysis of OA progression revealed that the intensity and duration of chondrocyte loss and cartilage lesion formation were significantly different in MCL-MM vs DMM. Firstly, apoptosis was seen prior to week two and was narrowly restricted to the weight bearing area. Four weeks post injury the magnitude of apoptosis led to a 40-60% reduction of chondrocytes in the non-calcified zone. Secondly, the progression of cell loss preceded the structural changes of the cartilage spatio-temporally. Lastly, while proteoglycan loss was similar in both models, collagen type II degradation only occurred more prominently in MCL-MM. Dynamics of chondrocyte loss and lesion formation in preclinical models has important implications for validating new therapeutic strategies. Our work could be helpful in assessing the feasibility and expected response of the DMM- and the MCL-MM models to chondrocyte mediated therapies.


Assuntos
Cartilagem Articular/fisiopatologia , Condrócitos/patologia , Meniscos Tibiais/fisiopatologia , Osteoartrite/fisiopatologia , Animais , Apoptose/genética , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Modelos Animais de Doenças , Humanos , Meniscos Tibiais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoartrite/genética , Osteoartrite/cirurgia , Proteoglicanas/genética , Proteoglicanas/metabolismo , Proteólise , Suporte de Carga/fisiologia
15.
Int J Mol Sci ; 20(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013670

RESUMO

The iliotibial band (ITB) is a suitable scaffold for anterior cruciate ligament (ACL) reconstruction, providing a sufficient mechanical resistance to loading. Hence, ITB-derived fibroblasts attract interest for ligament tissue engineering but have so far not been characterized. This present study aimed at characterizing ITB fibroblasts before, during, and after emigration from cadaveric ITB explants to decipher the emigration behavior and to utilize their migratory capacity for seeding biomaterials. ITB and, for comparison, ACL tissues were assessed for the content of alpha smooth muscle actin (αSMA) expressing fibroblasts and degeneration. The cell survival and αSMA expression were monitored in explants used for cell isolation, monolayer, self-assembled ITB spheroids, and spheroids seeded in polyglycolic acid (PGA) scaffolds. The protein expression profile of targets typically expressed by ligamentocytes (collagen types I-III, elastin, lubricin, decorin, aggrecan, fibronectin, tenascin C, CD44, ß1-integrins, vimentin, F-actin, αSMA, and vascular endothelial growth factor A [VEGFA]) was compared between ITB and ACL fibroblasts. A donor- and age-dependent differing percentage of αSMA positive cells could be detected, which was similar in ITB and ACL tissues despite the grade of degeneration being significantly higher in the ACL due to harvesting them from OA knees. ITB fibroblasts survived for several months in an explant culture, continuously forming monolayers with VEGFA and an increased αSMA expression. They shared their expression profile with ACL fibroblasts. αSMA decreased during the monolayer to spheroid/scaffold transition. Using self-assembled spheroids, the migratory capacity of reversible myofibroblastic ITB cells can be utilized for colonizing biomaterials for ACL tissue engineering and to support ligament healing.


Assuntos
Diferenciação Celular , Fascia Lata/citologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Ligamentos Articulares , Miofibroblastos/citologia , Regeneração , Adolescente , Adulto , Idoso , Biomarcadores , Técnicas de Cultura de Células , Sobrevivência Celular , Células Cultivadas , Criança , Pré-Escolar , Matriz Extracelular , Fascia Lata/metabolismo , Feminino , Imunofluorescência , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Lactente , Ligamentos Articulares/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Int J Mol Sci ; 19(7)2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30011964

RESUMO

Cultivation of autologous human tenocytes in a cell-free xenogenic extracellular tendon matrix (xECM) could present an approach for tendon reconstruction. The aim of this study was to achieve tendon-like tissue formation by implanting decellularized porcine Achilles tendons recellularized with human hamstring tendon-derived tenocytes into nude mice. The structure of decellularized xECM was histologically monitored before being dynamically reseeded with human tenocytes. After 6⁻12 weeks in vivo, construct quality was monitored using macroscopical and histological scoring systems, vitality assay and quantitative DNA and glycosaminoglycan (GAG) assays. For comparison to tendon xECM, a synthetic polyglycolic acid (PGA) polymer was implanted in a similar manner. Despite decellularized xECM lost some GAGs and structure, it could be recellularized in vitro with human tenocytes, but the cell distribution remained inhomogeneous, with accumulations at the margins of the constructs. In vivo, the xECM constructs revealed in contrast to the PGA no altered size, no inflammation and encapsulation and a more homogeneous cell distribution. xECM reseeded with tenocytes showed superior histological quality than cell-free implanted constructs and contained surviving human cells. Their DNA content after six and 12 weeks in vivo resembled that of native tendon and xECM recellularized in vitro. Results suggest that reseeded decellularized xECM formed a tendon-like tissue in vivo.


Assuntos
Tendão do Calcâneo/metabolismo , Matriz Extracelular/transplante , Xenoenxertos/metabolismo , Tenócitos/transplante , Tendão do Calcâneo/citologia , Animais , Células Cultivadas , Glicosaminoglicanos/metabolismo , Xenoenxertos/citologia , Humanos , Camundongos Nus , Ácido Poliglicólico/metabolismo , Suínos , Traumatismos dos Tendões/cirurgia , Tenócitos/citologia , Engenharia Tecidual/métodos , Transplante Heterólogo
17.
Am J Emerg Med ; 36(2): 343.e5-343.e6, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29146420

RESUMO

Acute Respiratory Distress Syndrome (ARDS) was first recognized during the 1960s. It is a distinct type of hypoxemic respiratory failure characterized by acute abnormality of both lungs. Extracorporeal membrane oxygenation (ECMO) is being increasingly used for patients with severe ARDS refractory to otherwise conventional management. A 29year old male arrived with Emergency Medical Services (EMS) status post presumed heroin overdose. He was administered Naloxone 2mg intravenously prior to arrival in the emergency department. The patient arrived in severe respiratory distress with a pulse oximetry level of 50% and was immediately intubated. The patient's pulse oximetry level remained in the seventies despite intubation and aggressive ventilator management. The Intensive Care Unit team in conjunction with cardiothoracic surgery initiated venovenous ECMO therapy in the emergency department itself. The patient was transferred to a tertiary center for venoarterial ECMO that was continued for 6 more days. After an extensive hospitalization, the patient was ultimately transferred to an acute medical rehabilitation center. With the current opioid crisis, emergency physicians and providers need to be aware that opioids can induce severe ARDS refractory to mechanical ventilation. ECMO as a treatment option can be used safely and successfully as described in this unique patient case report.


Assuntos
Analgésicos Opioides/intoxicação , Oxigenação por Membrana Extracorpórea/métodos , Unidades de Terapia Intensiva , Síndrome do Desconforto Respiratório/induzido quimicamente , Adulto , Humanos , Masculino , Síndrome do Desconforto Respiratório/terapia
18.
J Telemed Telecare ; 23(2): 360-364, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27365321

RESUMO

Introduction There is an increased demand for intensive care unit (ICU) beds. We sought to determine if we could create a safe surge capacity model to increase ICU capacity by treating ICU patients in the post-anaesthesia care unit (PACU) utilizing a collaborative model between an ICU service and a telemedicine service during peak ICU bed demand. Methods We evaluated patients managed by the surgical critical care service in the surgical intensive care unit (SICU) compared to patients managed in the virtual intensive care unit (VICU) located within the PACU. A retrospective review of all patients seen by the surgical critical care service from January 1st 2008 to July 31st 2011 was conducted at an urban, academic, tertiary centre and level 1 trauma centre. Results Compared to the SICU group ( n = 6652), patients in the VICU group ( n = 1037) were slightly older (median age 60 (IQR 47-69) versus 58 (IQR 44-70) years, p = 0.002) and had lower acute physiology and chronic health evaluation (APACHE) II scores (median 10 (IQR 7-14) versus 15 (IQR 11-21), p < 0.001). The average amount of time patients spent in the VICU was 13.7 + /-9.6 hours. In the VICU group, 750 (72%) of patients were able to be transferred directly to the floor; 287 (28%) required subsequent admission to the surgical intensive care unit. All patients in the VICU group were alive upon transfer out of the PACU while mortality in the surgical intensive unit cohort was 5.5%. Discussion A collaborative care model between a surgical critical care service and a telemedicine ICU service may safely provide surge capacity during peak periods of ICU bed demand. The specific patient populations for which this approach is most appropriate merits further investigation.


Assuntos
Unidades de Terapia Intensiva , Cuidados Pós-Operatórios/métodos , Telemedicina/métodos , Adulto , Idoso , Cuidados Críticos/métodos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Capacidade de Resposta ante Emergências
20.
Anesthesiol Clin ; 34(4): 659-668, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27816126

RESUMO

Patients with concomitant cardiac and hematologic disorders presenting for noncardiac surgery are challenging. Anemic patients with cardiac disease should be approached in a methodical fashion. Transfusion triggers and target should be based on underlying symptomatology. The approach to anticoagulation management in patients with artificial heart valves, cardiac devices, or severe heart failure in the operative setting must encompass a complete understanding of the rationale of a patient's therapy as well as calculate the risk of changing this regimen. This article focuses common disorders and discusses strategies to optimize care in patients with coexisting cardiac and hematologic disease.


Assuntos
Cardiopatias/complicações , Doenças Hematológicas/complicações , Anemia/complicações , Anemia Falciforme/complicações , Anticoagulantes/uso terapêutico , Transtornos Plaquetários/complicações , Insuficiência Cardíaca/complicações , Coração Auxiliar , Humanos
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