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1.
Int J Parasitol Parasites Wildl ; 23: 100895, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38187443

RESUMO

Alpine swifts (Tachymarptis melba) are sub-Saharan migratory birds, which, in Switzerland, nest in colonies that have been continuously monitored for over 40 years. In the summer of 2022, despite favourable environmental conditions, an unexpectedly high number of sudden mortalities (30-80%) occurred in 20 to 45-day-old nestlings from several nesting sites, of which 3 were monitored in detail. Nestlings submitted for post-mortem analysis (n = 5) were in good body condition but exhibited extensive subcutaneous haematomas (n = 5), myocardial petechiae (n = 2) and stunted growth of primary feathers (n = 1). In all birds, 4-5 µm large, amastigote-like protozoans were identified in skeletal and cardiac muscle sections. These tissues tested positive in a PCR targeting the 18S-rRNA gene of Trypanosoma spp. Amplified sequences showed 99.63% identity with sequences of Trypanosoma corvi (JN006854 and AY461665) and Trypanosoma sp. (AJ620557, JN006841). 72 blood smears of 45-day-old nestlings from two colonies were assessed, of which 20 contained trypomastigote forms, some with high parasitaemia (highest average of 56.4 in 10 high power fields, 400x magnification). Trypomastigote morphometrics (n = 36; mean total length = 30.0 µm; length of free flagellum = 5.8 µm) were consistent with those of T. bouffardi. These findings suggest that an avian trypanosomiasis causing mass nestling mortality could be an emerging disease in Swiss Alpine swift populations.

2.
Public Health Action ; 13(4): 119-122, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38077728

RESUMO

Self-testing for COVID-19 using antigen-detecting rapid diagnostic tests (Ag-RDTs) shows high promise in the Philippines. Self-testing has the potential to provide broader access to testing, empowering individuals by bringing healthcare services closer to them. We conducted 15 semi-structured interviews with health officers and decision-makers in the Philippines. These interviews explored the experiences and perspectives on the acceptability and feasibility of self-test use and implementation. We found that self-testing is easy-to-use, provides rapid results and can facilitate early detection. However, -regulatory policies, linkages to care and effective health -education plans must be in place for successful implementation.

3.
Ultrasound Obstet Gynecol ; 62(1): 148-151, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36806323

RESUMO

Anti-Ro/SSA-antibody-mediated endocardial fibroelastosis (EFE) without atrioventricular (AV) block at presentation is a rare cardiac phenotype. We report on 11 fetuses with this rare type of anti-Ro/SSA-antibody-mediated cardiac involvement, presenting with a distinctive echocardiographic pattern of EFE. Eleven fetuses with isolated EFE at presentation were included from four cardiac centers, and experienced fetal cardiologists reached a consensus regarding EFE location on echocardiography at presentation. Interval changes to subsequent fetal and postnatal echocardiograms were assessed to evaluate response to therapy. Echocardiographic markers of cardiac performance, including diastolic function and AV conduction, were reviewed. Ten fetuses were found to have EFE of the aortic root, proximal aorta and/or left ventricular outflow tract. In the same 10 cases, EFE of the pulmonary root, pulmonary artery and/or right ventricular outflow tract was identified. Six cases had atrial EFE and six had EFE of the crux. Four cases were known to be positive for anti-Ro/SSA antibodies prior to diagnosis, whereas, in the remaining seven, echocardiographic findings prompted testing, which was positive in all cases. The AV interval at presentation was normal in all cases, but one fetus subsequently developed AV block. Nine patients were treated with transplacental dexamethasone, five of which also received intravenous immunoglobulin (IVIG), and one received IVIG only. Of the 10 treated cases, six had improvement in EFE as shown by serial imaging and, in four cases, the severity was unchanged. All patients were liveborn. In our cohort, EFE of the aortic and pulmonary arteries and outflow tracts was nearly universal, and involvement of the atria and the crux of the heart was also common. The high survival rate and low burden of AV block are also suggestive of a distinct phenotype of anti-Ro/SSA-antibody-mediated cardiac disease with a favorable prognosis. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Bloqueio Atrioventricular , Fibroelastose Endocárdica , Gravidez , Feminino , Humanos , Imunoglobulinas Intravenosas , Feto , Fibroelastose Endocárdica/diagnóstico por imagem , Ecocardiografia/métodos
4.
Food Chem ; 376: 131917, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34968913

RESUMO

Understanding the mechanisms leading to the multitude of newly-formed compounds generated during the thermal processing of food is important for the reasoned construction of quality. Thanks to a solid food model with a structure and technological history comparable to that of a real sponge cake and containing only known amounts of precursors (glucose with or without leucine), an adapted reaction scheme unravelling Maillard and caramelization reactions was built and then compared to experimental kinetic data measured on numerous reaction markers (precursors, α-dicarbonyl intermediates and furanic compounds). For caramelization, this study showed that glucose mainly formed 1,2-enediol and then fructose rather than glucosone and glyoxal. 5-hydroxymethylfurfural started to form when there were sufficient quantities of fructose, and 3,4-dideoxyoglucosone was not generated until after this step. Furfural was mainly formed via 3-deoxyglucosone. The involvement of leucine tended to accelerate the breakdown of sugars as more degradation pathways (via enaminols) were added.

5.
Z Rheumatol ; 80(9): 884-888, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-33885949

RESUMO

We report the case of a 73-year-old female patient with malignant melanoma who developed rapidly progressive dermatosclerosis of the arms and legs as well as myalgia and flexion contractures during treatment with the immune checkpoint inhibitor nivolumab. The diagnosis of a myofasciitis was confirmed by imaging and biopsy. Following consultation with the treating dermato-oncologists nivolumab treatment was paused and treatment with methotrexate and prednisolone was initiated. Immune checkpoint inhibitors can induce a variety of immune-mediated side effects and can also imitate symptoms of rheumatological diseases. The occurrence of myofasciitis under immune checkpoint inhibition has been reported in the literature only in a few cases. Further oncological and rheumatological treatment management should be carried out in close interdisciplinary coordination.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Melanoma , Miosite , Idoso , Feminino , Humanos , Melanoma/tratamento farmacológico , Mialgia , Miosite/induzido quimicamente , Miosite/diagnóstico , Nivolumabe/efeitos adversos
6.
J Virol ; 95(7)2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33441344

RESUMO

Boid inclusion body disease (BIBD) causes losses in captive snake populations globally. BIBD is associated with the formation of cytoplasmic inclusion bodies (IBs), which mainly comprise reptarenavirus nucleoprotein (NP). In 2017, BIBD was reproduced by cardiac injection of boas and pythons with reptarenaviruses, thus demonstrating a causative link between reptarenavirus infection and the disease. Here, we report experimental infections of Python regius (n = 16) and Boa constrictor (n = 16) with three reptarenavirus isolates. First, we used pythons (n = 8) to test two virus delivery routes: intraperitoneal injection and tracheal instillation. Viral RNAs but no IBs were detected in brains and lungs at 2 weeks postinoculation. Next, we inoculated pythons (n = 8) via the trachea. During the 4 months following infection, snakes showed transient central nervous system (CNS) signs but lacked detectable IBs at the time of euthanasia. One of the snakes developed severe CNS signs; we succeeded in reisolating the virus from the brain of this individual and could demonstrate viral antigen in neurons. In a third attempt, we tested cohousing, vaccination, and sequential infection with multiple reptarenavirus isolates on boas (n = 16). At 10 months postinoculation, all but one snake tested positive for viral RNA in lung, brain, and/or blood, but none exhibited the characteristic IBs. Three of the four vaccinated snakes seemed to sustain challenge with the same reptarenavirus; however, neither of the two snakes rechallenged with different reptarenaviruses remained uninfected. Comparison of the antibody responses in experimentally versus naturally reptarenavirus-infected animals indicated differences in the responses.IMPORTANCE In the present study, we experimentally infected pythons and boas with reptarenavirus via either intraperitoneal injection or tracheal instillation. The aims were to experimentally induce boid inclusion body disease (BIBD) and to develop an animal model for studying disease transmission and pathogenesis. Both virus delivery routes resulted in infection, and infection via the trachea could reflect the natural route of infection. In the experimentally infected snakes, we did not find evidence of inclusion body (IB) formation, characteristic of BIBD, in pythons or boas. Most of the boas (11/12) remained reptarenavirus infected after 10 months, which suggests that they developed a persistent infection that could eventually have led to BIBD. We demonstrated that vaccination using recombinant protein or an inactivated virus preparation prevented infection by a homologous virus in three of four snakes. Comparison of the antibody responses of experimentally and naturally reptarenavirus-infected snakes revealed differences that merit further studies.

7.
Eur J Neurol ; 28(2): 367-376, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33012040

RESUMO

BACKGROUND AND PURPOSE: Patients with chronic focal epilepsy may have atrophy of brain structures important for the generation and maintenance of seizures. However, little research has been conducted in patients with newly diagnosed focal epilepsy (NDfE), despite it being a crucial point in time for understanding the underlying biology of the disorder. We aimed to determine whether patients with NDfE show evidence of volumetric abnormalities of subcortical structures. METHODS: Eighty-two patients with NDfE and 40 healthy controls underwent magnetic resonance imaging scanning using a standard clinical protocol. Volume estimation of the left and right hippocampus, thalamus, caudate nucleus, putamen and cerebral hemisphere was performed for all participants and normalised to whole brain volume. Volumes lower than two standard deviations below the control mean were considered abnormal. Volumes were analysed with respect to patient clinical characteristics, including treatment outcome 12 months after diagnosis. RESULTS: Volume of the left hippocampus (p(FDR-corr)  = 0.04) and left (p(FDR-corr)  = 0.002) and right (p(FDR-corr)  = 0.04) thalamus was significantly smaller in patients relative to controls. Relative to the normal volume limits in controls, 11% patients had left hippocampal atrophy, 17% had left thalamic atrophy and 9% had right thalamic atrophy. We did not find evidence of a relationship between volumes and future seizure control or with other clinical characteristics of epilepsy. CONCLUSIONS: Volumetric abnormalities of structures known to be important for the generation and maintenance of focal seizures are established at the time of epilepsy diagnosis and are not necessarily a result of the chronicity of the disorder.


Assuntos
Epilepsias Parciais , Epilepsia do Lobo Temporal , Atrofia/patologia , Encéfalo/patologia , Epilepsias Parciais/complicações , Epilepsias Parciais/diagnóstico por imagem , Epilepsia do Lobo Temporal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Tálamo/diagnóstico por imagem , Tálamo/patologia
8.
Urologe A ; 60(4): 475-483, 2021 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-33201297

RESUMO

INTRODUCTION: The aim of residency is to acquire medical skills and abilities. One didactic model is "Peyton's four-step approach". The aim of the present study was to develop and evaluate a modified Peytonian approach for group interactions. The aim was to develop a course for the acquisition of practical skills and training assistants in suture techniques for urology. METHODS: A prospective study was conducted with a total of 38 participants and 6 tutors. In a modified four-step Peytonian approach, various suturing and knotting techniques were taught in a structured manner. Tutors evaluated the procedural activity using observation sheets. In addition, the learning method was evaluated by the participants and the tutors at the end of the course. In order to check the long-term learning success, a renewed survey of the participants was conducted after 6 months. RESULTS: 80% of the participants rated the modified teaching method as useful and 83% of the tutors rated the procedural implementation as good. Fluid movement sequences were difficult independent of the technique taught. After 6 months, the participants significantly improved their procedural skills in all techniques that were taught. CONCLUSION: This paper defines a four-step Peyton-based approach to teaching practical skills such as suturing and knotting used in urological training. The modified teaching method improved practical skills used in urology. This method should be considered in continuing education to promote self-confidence and increase the competence in surgical skills.


Assuntos
Educação de Graduação em Medicina , Internato e Residência , Urologia , Competência Clínica , Currículo , Humanos , Estudos Prospectivos
9.
Theriogenology ; 156: 162-170, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32750597

RESUMO

Primary uterine inertia (PUI) is the most common type of dystocia in dogs. We hypothesized that PUI develops because of lower than normal expression of the basic contractile elements in the uterus, i.e., smooth muscle (SM) α- and γ-actin and SM-myosin, and that the expression of these proteins is influenced by the number of fetuses present in utero. Full-thickness inter-placental uterine biopsies were collected during Cesarean sections from dogs with PUI (n = 11), and from bitches with obstructive dystocia (OD) still presenting strong labor contractions (designated as the control group, n = 7). Relative gene expression was determined by semi-quantitative real-time (TaqMan) PCR, and protein localization by immunohistochemistry. Gene expression between PUI and OD bitches, and between PUI bitches carrying small, large, or average number of fetuses according to their breed, were compared. Uterine SM-γ-actin and SM-myosin mRNA levels were significantly higher in PUI than in OD dogs, while SM-α-actin did not differ. PUI bitches carrying large litters had lower uterine SM-γ-actin gene expression than those with small litters (P = 0.008). Immunostaining for SM-actin isoforms and SM-myosin was present in the myometrium, and localization pattern and staining intensity appeared similar in the PUI and OD groups. All proteins stained in blood vessels, and SM-γ-actin was also present in endometrial luminal and glandular epithelium. In conclusion, higher uterine SM-γ-actin and SM-myosin gene expression in PUI bitches, compared with OD dogs, might be an indication of abnormal progression with labor. Whether this is the cause of PUI due to an intrinsic error of the myometrium not becoming committed to labor, or the consequence of inadequate endocrine or mechanical stimuli, is not clear. Litter size was previously shown to be one of the risk factors for the development of uterine inertia in dogs, and our findings suggest possible differing uterine pathophysiology of PUI with respect to litter size.


Assuntos
Doenças do Cão , Distocia , Inércia Uterina , Actinas/genética , Animais , Cães , Distocia/veterinária , Feminino , Músculo Liso , Miosinas , Placenta , Gravidez , Miosinas de Músculo Liso , Inércia Uterina/veterinária , Útero
10.
Sci Rep ; 10(1): 12099, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694529

RESUMO

Contactless electroreflectance studies coupled with numerical calculations are performed on in-situ SiNx capped N-polar III-nitride high electron mobility transistor (HEMT) structures with a scaled channel thickness in order to analyse the built-in electric field in the GaN channel layer. The experimentally obtained field values are compared with the calculated field versus channel thickness curves. Furthermore, the experimental and theoretical sheet carrier densities, ns, are evaluated. While a gradual decrease in carrier concentration with decreasing channel thickness is expected for N-polar structures, experimentally a sudden drop in the ns values is observed for samples with very thin channels. The additional loss in charge was associated with a change in the SiNx/AlGaN interface Fermi level at very thin channel thicknesses.

11.
Br J Dermatol ; 183(2): 231-241, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32316070

RESUMO

BACKGROUND: Plaque psoriasis affects children and adults, but treatment options for paediatric psoriasis are limited. OBJECTIVES: To evaluate the efficacy and safety of ixekizumab (IXE), a high-affinity monoclonal antibody that selectively targets interleukin-17A, for moderate-to-severe paediatric psoriasis. METHODS: In a randomized, double-blind, placebo-controlled, phase III study (IXORA-PEDS), patients aged 6 to < 18 years with moderate-to-severe plaque psoriasis were randomized 2 : 1 to weight-based dosing of IXE every 4 weeks (IXE Q4W, n = 115) or placebo (n = 56) through week 12, followed by open-label IXE Q4W. Coprimary endpoints were the proportions of patients at week 12 achieving ≥ 75% improvement in Psoriasis Area and Severity Index (PASI 75) and those achieving a static Physician's Global Assessment score of 0 or 1 (sPGA 0,1). RESULTS: IXE was superior (P < 0·001) to placebo for both coprimary endpoints of PASI 75 (IXE Q4W, 89%; placebo, 25%) and sPGA (0,1) (IXE Q4W, 81%; placebo, 11%). IXE was also superior for all gated secondary endpoints, including PASI 75 and sPGA (0,1) at week 4, improvement in itch, and complete skin clearance. IXE Q4W provided significant (P < 0·001) improvements vs. placebo in quality of life and clearance of scalp and genital psoriasis. Responses at week 12 were sustained or further improved through week 48. Through week 12, 45% (placebo) and 56% (IXE) of patients reported treatment-emergent adverse events. One serious adverse event was reported (IXE), one patient discontinued due to an adverse event (placebo) and no deaths were reported. CONCLUSIONS: IXE was superior to placebo in the treatment of moderate-to-severe paediatric psoriasis, and the safety profile was generally consistent with that observed in adults. What is already known about this topic? Paediatric psoriasis affects approximately 1% of children and can negatively impact health-related quality of life. Treatment options for paediatric psoriasis are typically limited to off-label treatments and approved systemic biologics. Ixekizumab, a high-affinity monoclonal antibody that selectively targets interleukin-17A, is approved for moderate-to-severe plaque psoriasis in adults and was recently approved by the US Food and Drug Administration for moderate-to-severe paediatric psoriasis. What does this study add? Ixekizumab resulted in rapid and statistically significant improvements over placebo in skin involvement, itch and health-related quality of life, which persisted through 48 weeks of treatment in paediatric patients with moderate-to-severe plaque psoriasis. The safety profile of ixekizumab was generally consistent with that seen in adults. Ixekizumab may be an additional potential therapeutic option and an additional class of biologic therapy (interleukin-17A antagonist) for the treatment of moderate-to-severe paediatric psoriasis. Plain language summary available online.


Assuntos
Fármacos Dermatológicos , Psoríase , Adulto , Anticorpos Monoclonais Humanizados , Criança , Fármacos Dermatológicos/efeitos adversos , Método Duplo-Cego , Etanercepte , Humanos , Psoríase/tratamento farmacológico , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento
12.
Eur Radiol ; 30(5): 2830-2842, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31953666

RESUMO

OBJECTIVES: Diffusion tensor magnetic resonance imaging (DTI) and T2 mapping enable the detection of exercise-induced changes in the skeletal muscle microenvironment. This study prospectively quantified DTI metrics and T2 relaxation times of thigh muscles in competitive triathletes at rest and following a triathlon race in comparison with sedentary controls. METHODS: Twenty-two triathletes (males N = 16, females N = 6) and twenty-three controls (males N = 16, females N = 7) underwent magnetic resonance imaging (MRI) on a 3 T system at baseline (time point 1; 72 h at rest). Twelve triathletes (males N = 8, females N = 4) underwent a second scan (time point 2; 3 h of completing a triathlon race). The tensor eigenvalues (λ1, λ2, λ3), mean diffusivity (MD), fractional anisotropy (FA), and T2 times were compared between controls and triathletes at time point 1 and triathletes at time points 1 and 2 using independent and paired t tests. RESULTS: In comparison with the controls at time point 1, the T2 times of rectus femoris (RF, p < 0.02), adductor magnus (AM, p = 0.02), biceps femoris (BF, p < 0.001), semitendinosus (ST, p = 0.005), and semimembranosus (SM, p = 0.003) muscles were significantly increased in triathletes. At time point 2 in triathletes, the average tensor metrics (MD, λ3/ λ1) of BF, ST, and SM muscles increased (p < 0.05) and FA values in ST and SM muscles decreased (p < 0.03). T2 times were not significantly changed between both time points in triathletes. CONCLUSION: Our results indicate that this multiparametric MRI protocol allows detection and quantification of changes in the skeletal muscle microenvironment caused by endurance training and acute strenuous exercise. KEY POINTS: • Endurance training results in changes to the skeletal microstructure, which can be quantified using MRI-based diffusion tensor imaging. • The combined application of MRI diffusion tensor imaging and T2 mapping allows the differentiation of microstructural changes caused by active exercise or endurance training. • Environmental adaptations of the skeletal muscle caused by physical training are influenced by gender.


Assuntos
Atletas/estatística & dados numéricos , Imagem de Tensor de Difusão/métodos , Tolerância ao Exercício/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/anatomia & histologia , Coxa da Perna/anatomia & histologia , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos
13.
BJOG ; 127(2): 208-216, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31529767

RESUMO

OBJECTIVE: The objective of this study was to use high-throughput sequencing to describe the vaginal eukaryotic DNA virome in patients undergoing in vitro fertilisation (IVF) to examine associations between the vaginal virome, antibiotic exposure and IVF outcomes. DESIGN: Prospective exploratory study. SETTING: Single academic fertility centre. POPULATION: Subfertile women age 18-43 years undergoing their first IVF cycle with a fresh embryo transfer. METHODS: The primary exposure was prophylactic azithromycin or no azithromycin before IVF. A mid-vaginal swab was obtained at the time of embryo transfer for virome analysis. MAIN OUTCOME MEASURES: The primary outcomes compared between exposure groups were characteristics of vaginal virome and clinical pregnancy rates. Secondary outcomes were virome associations with number of oocytes retrieved, number of blastocysts and implantation rate. RESULTS: Twenty-six women contributed a vaginal swab before embryo transfer. There were no significant differences in IVF outcomes between azithromycin groups. There was no association between viral diversity and clinical pregnancy overall. A higher diversity of herpesviruses and α-papillomaviruses was observed in samples from the azithromycin-treated group compared with the no azithromycin group (P = 0.04). In women that received azithromycin, viral diversity was higher in the group that did not achieve clinical pregnancy compared with those who did (P = 0.06). CONCLUSIONS: We demonstrate that the vaginal eukaryotic virome in women undergoing IVF is associated with antibiotic exposure. Additionally, we demonstrate an inverse trend between viral diversity and pregnancy, with a higher number of viruses detected associated with failure to achieve clinical pregnancy in the azithromycin group. TWEETABLE ABSTRACT: Higher viral diversity is associated with prophylactic antibiotic exposure in subfertile women undergoing IVF.


Assuntos
Eucariotos/fisiologia , Fertilização in vitro , Infertilidade/terapia , Microbiota , Vagina/virologia , Adulto , Antibacterianos/uso terapêutico , DNA Viral/fisiologia , Transferência Embrionária , Feminino , Herpesviridae , Humanos , Microbiota/genética , Microbiota/imunologia , Papillomaviridae , Gravidez , Estudos Prospectivos , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/imunologia , Análise de Sequência de DNA , Vagina/microbiologia
14.
Acta Biomater ; 100: 292-305, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31568877

RESUMO

Cell-derived matrices (CDMs) provide an exogenous source of human extracellular matrix (ECM), with applications as cell delivery vehicles, substrate coatings for cell attachment and differentiation, and as biomaterial scaffolds. However, commercial application of CDMs has been hindered due to the prolonged culture time required for sufficient ECM accumulation. One approach to increasing matrix deposition in vitro is macromolecular crowding (MMC), which is a biophysical phenomenon that limits the diffusion of ECM precursor proteins, resulting in increased ECM accumulation at the cell layer. Hyaluronic acid (HA), a natural MMC highly expressed in vivo during fetal development, has been shown to play a role in ECM production, but has not been investigated as a macromolecule for increasing cell-mediated ECM deposition in vitro. In the current study, we hypothesized that HA can act as a MMC, and increase cell-mediated ECM production. Human dermal fibroblasts were cultured for 3, 7, or 14 days with 0%, 0.05%, or 0.5% high molecular weight HA. Ficoll 70/400 was used as a positive control. SDS-PAGE, Sircol, and hydroxyproline assays indicated that 0.05% HA-treated cultures had significantly higher mean collagen deposition at 14 days, whereas Ficoll 70/400-treated cultures had significantly lower collagen production compared to the HA and untreated controls. However, fluorescent immunostaining of ECM proteins and quantification of mean gray values did not indicate statistically significant differences in ECM production in HA or Ficoll 70/400-treated cultures compared to untreated controls. Raman imaging (a marker-free spectral imaging method) indicated that HA increased ECM deposition in human dermal fibroblasts. These results are consistent with decreases in CDM stiffness observed in Ficoll 70/400-treated cultures by atomic force microscopy. Overall, these results indicate that there are macromolecule- and cell type- dependent effects on matrix assembly, turnover, and stiffness in cell-derived matrices. STATEMENT OF SIGNIFICANCE: Cell-derived matrices (CDMs) are versatile biomaterials with many regenerative medicine applications, including as cell and drug delivery vehicles and scaffolds for wound healing and tissue regeneration. While CDMs have several advantages, their commercialization has been limited due to the prolonged culture time required to achieve CDM synthesis in vitro. In this study, we explored the use of hyaluronic acid (HA) as a macromolecular crowder in human fibroblast cell cultures to support production of CDM biomaterials. Successful application of macromolecular crowding will allow development of human cell-derived, xeno-free biomaterials that re-capitulate the native human tissue microenvironment.


Assuntos
Matriz Extracelular/metabolismo , Fibroblastos/citologia , Ácido Hialurônico/farmacologia , Substâncias Macromoleculares/química , Animais , Bovinos , Células Cultivadas , Colágeno/química , Matriz Extracelular/efeitos dos fármacos , Fibronectinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis/farmacologia , Recém-Nascido , Laminina/metabolismo , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Polímeros/farmacologia , Solubilidade , Análise Espectral Raman , Viscosidade
16.
Biochim Biophys Acta Biomembr ; 1861(6): 1123-1134, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902626

RESUMO

Influenza A virus is a pathogen responsible for severe seasonal epidemics threatening human and animal populations every year. One of the ten major proteins encoded by the viral genome, the matrix protein M1, is abundantly produced in infected cells and plays a structural role in determining the morphology of the virus. During assembly of new viral particles, M1 is recruited to the host cell membrane where it associates with lipids and other viral proteins. The structure of M1 is only partially known. In particular, structural details of M1 interactions with the cellular plasma membrane as well as M1-protein interactions and multimerization have not been clarified, yet. In this work, we employed a set of complementary experimental and theoretical tools to tackle these issues. Using raster image correlation, surface plasmon resonance and circular dichroism spectroscopies, we quantified membrane association and oligomerization of full-length M1 and of different genetically engineered M1 constructs (i.e., N- and C-terminally truncated constructs and a mutant of the polybasic region, residues 95-105). Furthermore, we report novel information on structural changes in M1 occurring upon binding to membranes. Our experimental results are corroborated by an all-atom model of the full-length M1 protein bound to a negatively charged lipid bilayer.


Assuntos
Lipídeos de Membrana/metabolismo , Proteínas da Matriz Viral/metabolismo , Lipídeos de Membrana/química , Ligação Proteica , Multimerização Proteica , Estrutura Secundária de Proteína , Proteínas da Matriz Viral/química
17.
Clin Radiol ; 74(1): 78.e1-78.e11, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30274684

RESUMO

AIM: To evaluate whether a dedicated epilepsy research protocol with expert image re-evaluation can increase identification of patients with lesions and to attempt to ascertain the potential reasons why lesions were not identified previously on earlier clinical magnetic resonance imaging (MRI). MATERIALS AND METHODS: Forty-three patients (26 female) with focal refractory epilepsy who had failed at least two trials of anti-epileptic drug treatments were studied. Patients were recruited prospectively into the study if previous clinical MRI was deemed to be "non-lesional" by the clinicians involved in the initial assessment. Three-dimensional (3D) T1-weighted (T1W), T2-weighted (T2W), T2 fluid-attenuated inversion recovery (T2-FLAIR) sequences, and two-dimensional (2D) coronal T1-/T2W FLAIR were assessed by a neuroradiologist, including the previous clinical MRI of individual patients. RESULTS: Twenty-nine or 43 (67%) patients remained MRI-negative after scanning with the epilepsy-dedicated protocol and image reappraisal by expert consultant neuroradiologists; however, 14/43 (33%) patients were found to have potentially epileptogenic brain lesions. The lesion that most frequently escaped the attention of clinicians was hippocampal sclerosis (nine cases, of which two had an additional focal cortical dysplasia, FCD), followed by single FCDs (two cases), and others including gliosis, encephalocoele, and amygdala enlargement (one case each). Eleven of the 14 (79%) previously "non-lesional" patients had electroencephalogram (EEG) imaging-concordant localisation features, rendering them potential candidates for resective surgery. CONCLUSIONS: The primary factors explaining the newly identified lesions were the choice of MRI sequences, imaging parameters, data quality, lesion not reported (human factor), and loss of information through incomplete documentation. It is important for all clinicians to proceed meticulously in the detailed assessment of epilepsy-dedicated in-vivo MRI and discuss difficult patient cases in multidisciplinary team meetings.


Assuntos
Encéfalo/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsias Parciais/diagnóstico por imagem , Neuroimagem , Adolescente , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Encéfalo/patologia , Protocolos Clínicos , Epilepsia Resistente a Medicamentos/patologia , Eletroencefalografia , Epilepsias Parciais/patologia , Feminino , Gliose/diagnóstico por imagem , Gliose/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose/diagnóstico por imagem , Esclerose/patologia , Adulto Jovem
18.
Clin Microbiol Infect ; 25(7): 857-864, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30395932

RESUMO

OBJECTIVES: Parapneumonic pleural effusions/empyema (PPE/PE) are severe complications of community-acquired pneumonia. We investigated the bacterial aetiology and incidence of paediatric PPE/PE in Germany after the introduction of universal pneumococcal conjugate vaccine (PCV) immunization for infants. METHODS: Children <18 years of age hospitalized with pneumonia-associated PPE/PE necessitating pleural drainage or persisting >7 days were reported to the German Surveillance Unit for Rare Diseases in Childhood between October 2010 and June 2017. All bacteria detected in blood or pleural fluid (by culture/PCR) were included, with serotyping for Streptococcus pneumoniae. RESULTS: The median age of all 1447 PPE/PE patients was 5 years (interquartile range 3-10). In 488 of the 1447 children with PPE/PE (34%), 541 bacteria (>40 species) were detected. Aerobic gram-positive cocci accounted for 469 of 541 bacteria detected (87%); these were most frequently Streptococcus pneumoniae (41%), Streptococcus pyogenes (19%) and Staphylococcus aureus (6%). Serotype 3 accounted for 45% of 78 serotyped S. pneumoniae strains. Annual PPE/PE incidence varied between 14 (95%CI 12-16) and 18 (95%CI 16-21) PPE/PE per million children. Incidence of S. pneumoniae PPE/PE decreased from 3.5 (95%CI 2.5-4.6) per million children in 2010/11 to 1.5 (95%CI 0.9-2.4) in 2013/14 (p 0.002), followed by a re-increase to 2.2 (95%CI 1.5-3.2) by 2016/17 (p 0.205). CONCLUSIONS: In the era of widespread PCV immunization, cases of paediatric PPE/PE were still caused mainly by S. pneumoniae and, increasingly, by S. pyogenes. The re-increase in the incidence of PPE/PE overall and in S. pneumoniae-associated PPE/PE indicates ongoing changes in the bacterial aetiology and requires further surveillance.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Empiema Pleural/epidemiologia , Derrame Pleural/epidemiologia , Pneumonia Bacteriana/epidemiologia , Adolescente , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/complicações , Empiema Pleural/microbiologia , Monitoramento Epidemiológico , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Lactente , Masculino , Derrame Pleural/microbiologia , Vacinas Pneumocócicas/administração & dosagem , Pneumonia Bacteriana/complicações , Reação em Cadeia da Polimerase , Estudos Prospectivos , Sorotipagem , Staphylococcus aureus/isolamento & purificação , Streptococcus/isolamento & purificação , Vacinação/estatística & dados numéricos , Vacinas Conjugadas/administração & dosagem
19.
Clin Neuroradiol ; 29(2): 231-242, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29392347

RESUMO

PURPOSE: To compare the influence of two different regions of interest (ROIs) on diffusion tensor metrics in dystrophic thigh muscles using a custom-made (whole muscle) ROI including and a selective ROI excluding areas of fatty replacement. METHODS: Diffusion tensor imaging (DTI) and chemical-shift-encoded water-fat magnetic resonance imaging (MRI) of the thigh was conducted on a 3-Tesla system in 15 cases with muscular dystrophy and controls. The ROIs were chosen according to patterns of fatty replacement on co-registered axial DTI and gradient echo sequence (GRE) images. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), fiber track length (FTL), and muscle fat fractions (MFF) were compared between both ROI segmentations. These comparisons, muscle-specific correlation coefficients, and the influence of ROI localization on tensor metrics were derived based on linear mixed effects regression models. RESULTS: In the cases a high correlation was observed for ADC and FA with MFF using a custom ROI. The correlation was weaker but still significant with a selective ROI method. Using the custom ROI, FTL correlated significantly with MFF in 3 out of 4 muscles (r ≤ -0.51). A correlation was not found for the selective ROI method. Interaction analysis revealed that the association of ADC and FA with MFF was not significantly influenced by the ROI localization. For FTL the ROI localization significantly reduced the negative association with MFF. CONCLUSION: The DTI metrics and FTL of custom ROI segmentation are significantly influenced by MFF. Contrary to ADC and FA, the effect of MFF on FTL is significantly reduced when applying selective ROI segmentation, which could therefore be a better option for MR tractography.


Assuntos
Músculo Esquelético/patologia , Distrofias Musculares/patologia , Tecido Adiposo/patologia , Adulto , Idoso , Água Corporal , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Coxa da Perna , Adulto Jovem
20.
Eur Radiol ; 29(2): 818-828, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30014204

RESUMO

PURPOSE: To assess the diagnostic value of multiparametric magnetic resonance imaging (MRI) including dynamic Gd-EOB-DTPA-enhanced (DCE) and diffusion-weighted (DW) imaging for diagnosis and staging of hepatic fibrosis in primary sclerosing cholangitis (PSC) using transient elastography as a standard reference. MATERIAL AND METHODS: Multiparametric MRI was prospectively performed on a 3.0-Tesla scanner in 47 patients (age 43.9±14.3 years). Transient elastography derived liver stiffness measurements (LSM), DCE-MRI derived parameters (hepatocellular uptake rate (Ki), arterial (Fa), portal venous (Fv) and total (Ft) blood flow, mean transit time (MTT), and extracellular volume (Ve)) and the apparent diffusion coefficient (ADC) were calculated. Correlation and univariate analysis of variance with post hoc pairwise comparison were applied to test for differences between LSM derived fibrosis stages (F0/F1, F2/3, F4). ROC curve analysis was used as a performance measure. RESULTS: Both ADC and Ki correlated significantly with LSM (r= -0.614; p<0.001 and r= -0.368; p=0.01). The ADC significantly discriminated fibrosis stages F0/1 from F2/3 and F4 (p<0.001). Discrimination of F0/1 from F2/3 and F4 reached a sensitivity/specificity of 0.917/0.821 and 0.8/0.929, respectively. Despite significant inter-subject effect for classification of fibrosis stages, post hoc pairwise comparison was not significant for Ki (p>0.096 for F0/1 from F2/3 and F4). LSM, ADC and Ki were significantly associated with serum-based liver functional tests, disease duration and spleen volume. CONCLUSION: DW-MRI provides a higher diagnostic performance for detection of hepatic fibrosis and cirrhosis in PSC patients in comparison to Gd-EOB-DTPA-enhanced DCE-MRI. KEY POINTS: • Both ADC and hepatocellular uptake rate (Ki) correlate significantly with liver stiffness (r= -0.614; p<0.001 and r= -0.368; p=0.01). • The DCE-imaging derived quantitative parameter hepatocellular uptake rate (Ki) fails to discriminate pairwise intergroup differences of hepatic fibrosis (p>0.09). • DWI is preferable to DCE-imaging for discrimination of fibrosis stages F0/1 to F2/3 (p<0.001) and F4 (p<0.001).


Assuntos
Colangite Esclerosante/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Colangite Esclerosante/complicações , Meios de Contraste , Estudos Transversais , Imagem de Difusão por Ressonância Magnética/métodos , Técnicas de Imagem por Elasticidade/métodos , Feminino , Gadolínio DTPA , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Veia Porta/diagnóstico por imagem , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Baço/diagnóstico por imagem , Baço/patologia
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