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1.
Brain ; 145(3): 1001-1017, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35285474

RESUMO

Synucleinopathies encompass several neurodegenerative diseases, which include Parkinson's disease, dementia with Lewy bodies and multiple system atrophy. These diseases are characterized by the deposit of α-synuclein aggregates in intracellular inclusions in neurons and glial cells. Unlike Parkinson's disease and dementia with Lewy bodies, where aggregates are predominantly neuronal, multiple system atrophy is associated with α-synuclein cytoplasmic inclusions in oligodendrocytes. Glial cytoplasmic inclusions are the pathological hallmark of multiple system atrophy and are associated with neuroinflammation, modest demyelination and, ultimately, neurodegeneration. To evaluate the possible pathogenic role of glial cytoplasmic inclusions, we inoculated glial cytoplasmic inclusion-containing brain fractions obtained from multiple system atrophy patients into the striatum of non-human primates. After a 2-year in vivo phase, extensive histochemical and biochemical analyses were performed on the whole brain. We found loss of both nigral dopamine neurons and striatal medium spiny neurons, as well as loss of oligodendrocytes in the same regions, which are characteristics of multiple system atrophy. Furthermore, demyelination, neuroinflammation and α-synuclein pathology were also observed. These results show that the α-synuclein species in multiple system atrophy-derived glial cytoplasmic inclusions can induce a pathological process in non-human primates, including nigrostriatal and striatofugal neurodegeneration, oligodendroglial cell loss, synucleinopathy and gliosis. The present data pave the way for using this experimental model for MSA research and therapeutic development.


Assuntos
Doenças Desmielinizantes , Doença por Corpos de Lewy , Atrofia de Múltiplos Sistemas , Doença de Parkinson , Sinucleinopatias , Animais , Encéfalo/patologia , Doenças Desmielinizantes/patologia , Humanos , Corpos de Inclusão/metabolismo , Doença por Corpos de Lewy/patologia , Atrofia de Múltiplos Sistemas/patologia , Doença de Parkinson/patologia , alfa-Sinucleína/metabolismo
2.
Fish Shellfish Immunol ; 123: 431-441, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35337979

RESUMO

The current work aimed to carry out an in vivo study of the λ-carrageenin-induced inflammation in the skin of gilthead seabream (Sparus aurata). The fish were injected intramuscularly with phosphate-buffered saline (PBS, as control) or λ-carrageenin (1% in PBS), and the injection zone was evaluated by real-time ultrasonography (Vevo Lab, VisualSonics) at 1.5, 3, 6, 12, and 24 h post-injection (p.i.). Results demonstrated that the skin thickness was increased in fish injected with λ-carrageenin and sampled at 1.5, 3, and 6 h p.i. However, the skin thickness of the injected area decreased to the normal values in those fish sampled at 12 and 24 h p.i. In addition, fish injected with λ-carrageenin and analysed at 1.5, 3, and 6 h p.i. showed, in the underlying muscle at the injection place, several hyperechoic small foci surrounded by an anechoic area which were not observed in control fish. Furthermore, the fish were analysed by X-ray micro-computed tomography (micro-CT). The analysis of the micro-CT acquisitions revealed also a dark area in the place of the injection with λ-carrageenin at 1.5, 3, and 6 h. These areas were smaller in fish analysed at longer times (12 h p.i.) and were almost disappeared in fish sampled at 24 h p.i. These areas had an average density of -850 to -115 HU, which did not correspond with any tissue density of the rest of the body. Furthermore, similar dark areas at the injection zones were never observed in control fish. Present results support the use of both non-invasive techniques to study the inflammatory process in fish of commercial interest such as gilthead seabream.


Assuntos
Dourada , Animais , Carragenina , Músculos , Dourada/fisiologia , Ultrassonografia , Microtomografia por Raio-X
3.
Genet Med ; 23(11): 2067-2075, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34257421

RESUMO

PURPOSE: To evaluate the safety and efficacy of N-acetylmannosamine (ManNAc) in GNE myopathy, a genetic muscle disease caused by deficiency of the rate-limiting enzyme in N-acetylneuraminic acid (Neu5Ac) biosynthesis. METHODS: We conducted an open-label, phase 2, single-center (NIH, USA) study to evaluate oral ManNAc in 12 patients with GNE myopathy (ClinicalTrials.gov NCT02346461). Primary endpoints were safety and biochemical efficacy as determined by change in plasma Neu5Ac and sarcolemmal sialylation. Clinical efficacy was evaluated using secondary outcome measures as part of study extensions, and a disease progression model (GNE-DPM) was tested as an efficacy analysis method. RESULTS: Most drug-related adverse events were gastrointestinal, and there were no serious adverse events. Increased plasma Neu5Ac (+2,159 nmol/L, p < 0.0001) and sarcolemmal sialylation (p = 0.0090) were observed at day 90 compared to baseline. A slower rate of decline was observed for upper extremity strength (p = 0.0139), lower extremity strength (p = 0.0006), and the Adult Myopathy Assessment Tool (p = 0.0453), compared to natural history. Decreased disease progression was estimated at 12 (γ = 0.61 [95% CI: 0.09, 1.27]) and 18 months (γ = 0.55 [95% CI: 0.12, 1.02]) using the GNE-DPM. CONCLUSION: ManNAc showed long-term safety, biochemical efficacy consistent with the intended mechanism of action, and preliminary evidence clinical efficacy in patients with GNE myopathy.


Assuntos
Miopatias Distais , Doenças Musculares , Adulto , Hexosaminas , Humanos , Doenças Musculares/induzido quimicamente , Doenças Musculares/tratamento farmacológico , Doenças Musculares/genética , Ácido N-Acetilneuramínico
4.
Brain ; 143(5): 1462-1475, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32380543

RESUMO

In Parkinson's disease, synucleinopathy is hypothesized to spread from the enteric nervous system, via the vagus nerve, to the CNS. Here, we compare, in baboon monkeys, the pathological consequences of either intrastriatal or enteric injection of α-synuclein-containing Lewy body extracts from patients with Parkinson's disease. This study shows that patient-derived α-synuclein aggregates are able to induce nigrostriatal lesions and enteric nervous system pathology after either enteric or striatal injection in a non-human primate model. This finding suggests that the progression of α-synuclein pathology might be either caudo-rostral or rostro-caudal, varying between patients and disease subtypes. In addition, we report that α-synuclein pathological lesions were not found in the vagal nerve in our experimental setting. This study does not support the hypothesis of a transmission of α-synuclein pathology through the vagus nerve and the dorsal motor nucleus of the vagus. Instead, our results suggest a possible systemic mechanism in which the general circulation would act as a route for long-distance bidirectional transmission of endogenous α-synuclein between the enteric and the central nervous systems. Taken together, our study provides invaluable primate data exploring the role of the gut-brain axis in the initiation and propagation of Parkinson's disease pathology and should open the door to the development and testing of new therapeutic approaches aimed at interfering with the development of sporadic Parkinson's disease.


Assuntos
Encéfalo/patologia , Neuroimunomodulação/fisiologia , Doença de Parkinson/fisiopatologia , Nervo Vago/patologia , alfa-Sinucleína/toxicidade , Idoso , Animais , Sistema Nervoso Entérico/efeitos dos fármacos , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/patologia , Feminino , Humanos , Corpos de Lewy/metabolismo , Corpos de Lewy/patologia , Masculino , Papio , alfa-Sinucleína/administração & dosagem
5.
Oral Dis ; 27(6): 1580-1589, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33031620

RESUMO

OBJECTIVES: To use tissue engineering muscle repair (TEMR) for regenerating the lingual musculature of hemiglossectomized rats using neonatal myoblasts (NM) on porcine acellular urinary bladder matrix (AUBM). MATERIAL AND METHODS: The study used 80 male rats. A volumetric muscle loss (VML) injury was created on the left side of the tongue. The rats were randomized into four groups: Group 1 (AUBM + myoblasts); Group 2 (AUBM); Group 3 (myoblasts); and Group 4 (control). NM were obtained from neonatal rats. The animals were weighed on day 0 and just before euthanasia. Five rats in each group were euthanized at days 2, 14, 28, and 42; the tongues were prepared for morphometric analysis, postoperative left hemitongue weight, and immunohistochemical analysis (desmin, CD-31, and anti-neurofilament). RESULTS: The weight gain from greatest to least was as follows: AUBM + myoblasts > myoblasts > AUBM > control. The tongue dorsum occupied by VML, and difference in mg between control side and intervened side from least to great was as follows: AUBM + myoblasts < myoblasts < AUBM < control. The order from highest to lowest antibody positivity was as follows: AUBM + myoblasts > myoblasts > AUBM > control. CONCLUSION: The use of porcine AUBM and NM for the regeneration of lingual musculature was found to be an effective TEMR treatment for repairing tongue VML injury.


Assuntos
Engenharia Tecidual , Bexiga Urinária , Animais , Masculino , Mioblastos , Ratos , Regeneração , Suínos , Língua , Bexiga Urinária/cirurgia
6.
J Fish Dis ; 44(8): 1091-1100, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33760262

RESUMO

This work aimed to carry out an in vivo study of the skin healing process in gilthead seabream (Sparus aurata) after being experimentally wounded. Firstly, the structure of normal skin was studied by real-time ultrasonography (Vevo Lab, VisualSonics) and light microscopy. Besides this, experimental wounds were made on the left flank of each fish with a circular biopsy punch (8 mm diameter) below the lateral line. The healing process was assessed on live fish at 0, 6, 11 and 23 days post-wounding using the real-time ultrasonography in B-mode and Power Doppler mode (Vevo 3100 FUJIFILM, VisualSonics). Through the ultrasonography images, both the skin structure and the evolution of the changes that wounds originated in the surrounding tissues were studied in vivo over time. Concomitantly, the pattern of neovascularization in the wounded area was followed during the healing process and it was demonstrated that, although the neovascularization started very early after the skin damage, it was increased in wounded areas from day 11 post-wounding onwards. The results obtained proved the utility and power of using ultrasounds in fish to evaluate in vivo complex biological processes in real time, which are difficult to study by other methodologies. The present data shed some light on the reparation of external injuries in aquatic vertebrates.


Assuntos
Dourada/fisiologia , Pele/lesões , Cicatrização , Animais , Dourada/lesões , Ultrassonografia
7.
Biomed Chromatogr ; 34(2): e4735, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31691999

RESUMO

The biosynthesis of sialic acid (Neu5Ac) leads to the intracellular production of cytidine-5'-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac), the active sialic acid donor to nascent glycans (glycoproteins and glycolipids) in the Golgi. UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase myopathy is a rare autosomal recessive muscular disease characterized by progressive muscle weakness and atrophy. To quantify the intracellular levels of CMP-Neu5Ac as well as N-acetylmannosamine (ManNAc) and Neu5Ac in human leukocytes, we developed and validated robust liquid chromatography-tandem mass spectrometry methods. A fit-for-purpose approach was implemented for method validation. Hydrophilic interaction chromatography was used to retain three hydrophilic analytes. The human leukocyte pellets were lysed and extracted in a methanol-water mixture and the leukocyte extract was used for LC-MS/MS analysis. The lower limits of quantitation for ManNAc, Neu5Ac and CMP-Neu5Ac were 25.0, 25.0 and 10.0 ng/ml, respectively. These validated methods were applied to a clinical study.


Assuntos
Cromatografia Líquida/métodos , Monofosfato de Citidina/análogos & derivados , Leucócitos/química , Ácidos Siálicos/sangue , Espectrometria de Massas em Tandem/métodos , Monofosfato de Citidina/sangue , Estabilidade de Medicamentos , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
8.
J Fish Biol ; 97(5): 1440-1447, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32840010

RESUMO

In recent years, the increasing use of fish as new animal models in scientific research and the growth of fish farming (mainly for human consumption) have highlighted the need for advanced technology to deepen our knowledge of fish biology. Hence, the present study was carried out to radiologically analyse the whole body of gilthead seabream (Sparus aurata) specimens using X-ray computed tomography (CT). Images were acquired in an Albira SPECT/PET/CT tri-modal preclinical-scanner. Segmentation, measurements and three-dimensional reconstruction were made using the Carestream Molecular imaging Albira CT system in conjunction with Pmod, AMIDE and Amira software packages. The results showed that the density values of gilthead seabream are in the range -700 to +2500 HU for the whole body. We also determined the density ranges that topographically coincide with the swim bladder, soft tissues, fat, skin and skeleton. This work describes, validates and demonstrates the application of a fully automated image analysis technique to study and quantify fish body composition, whether segmented or as a whole. In addition, the basis for applying this image technique in other in vivo studies is established.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Dourada , Imagem Corporal Total/veterinária , Animais , Processamento de Imagem Assistida por Computador , Dourada/anatomia & histologia , Imagem Corporal Total/métodos
9.
Muscle Nerve ; 58(2): 286-292, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29603301

RESUMO

INTRODUCTION: GNE myopathy is an adult-onset muscle disorder characterized by impaired sialylation of (muscle) glycans, detectable by lectin histochemistry. We describe a standardized method to quantify (lectin-) fluorescence in muscle sections, applicable for diagnosis and response to therapy for GNE myopathy. METHODS: Muscle sections were fluorescently labeled with the sialic acid-binding Sambucus nigra agglutinin (SNA) lectin and antibodies to sarcolemma residence protein caveolin-3 (CAV-3). Entire tissue sections were imaged in tiles and fluorescence was quantified. RESULTS: SNA fluorescence co-localizing with CAV-3 was ∼50% decreased in GNE myopathy biopsies compared with muscle-matched controls, confirming previous qualitative results. DISCUSSION: This quantitative fluorescence method can accurately determine sialylation status of GNE myopathy muscle biopsies. This method is adaptable for expression of other membrane-associated muscle proteins, and may be of benefit for disorders in which therapeutic changes in expression are subtle and difficult to assess by other methods. Muscle Nerve 58: 286-292, 2018.


Assuntos
Miopatias Distais/patologia , Lectinas , Músculo Esquelético/patologia , Adulto , Caveolina 3/genética , Miopatias Distais/genética , Feminino , Corantes Fluorescentes , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Lectinas de Plantas , Proteínas Inativadoras de Ribossomos , Sarcolema/patologia , Sarcolema/ultraestrutura
10.
Mol Genet Metab ; 122(1-2): 126-134, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28641925

RESUMO

GNE myopathy is a rare, autosomal recessive, inborn error of sialic acid metabolism, caused by mutations in GNE, the gene encoding UDP-N-acetyl-glucosamine-2-epimerase/N-acetylmannosamine kinase. The disease manifests as an adult-onset myopathy characterized by progressive skeletal muscle weakness and atrophy. There is no medical therapy available for this debilitating disease. Hyposialylation of muscle glycoproteins likely contributes to the pathophysiology of this disease. N-acetyl-D-mannosamine (ManNAc), an uncharged monosaccharide and the first committed precursor in the sialic acid biosynthetic pathway, is a therapeutic candidate that prevents muscle weakness in the mouse model of GNE myopathy. We conducted a first-in-human, randomized, placebo-controlled, double-blind, single-ascending dose study to evaluate safety and pharmacokinetics of ManNAc in GNE myopathy subjects. Single doses of 3 and 6g of oral ManNAc were safe and well tolerated; 10g was associated with diarrhea likely due to unabsorbed ManNAc. Oral ManNAc was absorbed rapidly and exhibited a short half-life (~2.4h). Following administration of a single dose of ManNAc, there was a significant and sustained increase in plasma unconjugated free sialic acid (Neu5Ac) (Tmax of 8-11h). Neu5Ac levels remained above baseline 48h post-dose in subjects who received a dose of 6 or 10g. Given that Neu5Ac is known to have a short half-life, the prolonged elevation of Neu5Ac after a single dose of ManNAc suggests that intracellular biosynthesis of sialic acid was restored in subjects with GNE myopathy, including those homozygous for mutations in the kinase domain. Simulated plasma concentration-time profiles support a dosing regimen of 6g twice daily for future clinical trials.


Assuntos
Miopatias Distais/tratamento farmacológico , Hexosaminas/efeitos adversos , Hexosaminas/farmacocinética , Ácido N-Acetilneuramínico/sangue , Administração Oral , Adulto , Idoso , Alelos , Animais , Miopatias Distais/genética , Miopatias Distais/fisiopatologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hexosaminas/administração & dosagem , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Músculos/efeitos dos fármacos , Músculos/metabolismo , Mutação , Ácido N-Acetilneuramínico/biossíntese , Fosfotransferases (Aceptor do Grupo Álcool)/genética
11.
Bioengineering (Basel) ; 10(6)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37370569

RESUMO

This study aimed to assess the bone regeneration of critical-size defects in rabbit calvaria filled with freshly crushed extracted teeth, comparing them with BTCP biomaterial and empty sites. Materials and methods: Twenty-one female New Zealand rabbits were used in this study. Two critical-size defects 6 mm in size were created in the skull bone, each with a 3 mm separation between them. Three experimental groups were evaluated: Group A (human sterilized crushed teeth granules alone), Group B (Bioner Bone, Bioner Sitemas Implantológicos), and Group C (unfilled defects). The animals were sacrificed at 4 and 8 weeks. Evaluation of the samples involved histological and histomorphometric analyses with radiographic evaluation. The histological evaluation showed a higher volume reduction in Group A compared with Group B (p < 0.05) and Control. Group A showed the highest values for cortical closure and bone formation around the particles, followed by Group B and Group C (p < 0.05). Within the limitations of this animal study, we can conclude that the use of human tooth particles leads to increased bone formation and reduced connective tissue in critical-size defects in rabbit calvaria when compared to BTCP biomaterial. The calvarial model is a robust base for the evaluation of different biomaterials.

12.
NPJ Parkinsons Dis ; 9(1): 135, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726343

RESUMO

Aggregation of α-synuclein (α-syn) is the cornerstone of neurodegenerative diseases termed synucleinopathies, which include Parkinson's Disease (PD), Dementia with Lewy Bodies (DLB), and Multiple System Atrophy (MSA). These synucleinopathies are characterized by the deposit of aggregated α-syn in intracellular inclusions observable in neurons and glial cells. In PD and DLB, these aggregates, predominantly located in neurons, are called Lewy Bodies (LBs). These LBs are one of the pathological hallmarks of PD and DLB, alongside dopaminergic neuron loss in the substantia nigra. Previous studies have demonstrated the ability of PD patient-derived LB fractions to induce nigrostriatal neurodegeneration and α-syn pathology when injected into the striatum or the enteric nervous system of non-human primates. Here, we report the pathological consequences of injecting these LB fractions into the cortex of non-human primates. To this end, we inoculated mesencephalic PD patient-derived LB fractions into the prefrontal cortex of baboon monkeys terminated one year later. Extensive analyses were performed to evaluate pathological markers known to be affected in LB pathologies. We first assessed the hypothesized presence of phosphorylated α-syn at S129 (pSyn) in the prefrontal cortices. Second, we quantified the neuronal, microglial, and astrocytic cell survival in the same cortices. Third, we characterized these cortical LB injections' putative impact on the integrity of the nigrostriatal system. Overall, we observed pSyn accumulation around the injection site in the dorsal prefrontal cortex, in connected cortical regions, and further towards the striatum, suggesting α-syn pathological propagation. The pathology was also accompanied by neuronal loss in these prefrontal cortical regions and the caudate nucleus, without, however, loss of nigral dopamine neurons. In conclusion, this pilot study provides novel data demonstrating the toxicity of patient-derived extracts, their potential to propagate from the cortex to the striatum in non-human primates, and a possible primate model of DLB.

13.
Photobiomodul Photomed Laser Surg ; 40(5): 325-333, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35559716

RESUMO

Background and objective: Laser applied at low power (400-1100 nm), currently named photobiomodulation (PBM), is a noninvasive therapy to speed up wound healing. The purpose of this study was whether two different laser PBM delivery protocols would impact the skin wound healing in a mouse model. Materials and methods: A total of 24 SKH-1 mice were divided into three groups: Group 1 (control: untreated ulcers), Group 2 (a single postsurgical laser application), and Group 3 (laser each other day for 10 days; total five applications). Laser parameters were 940 nm, 0.4 W, 10 mm spot size, 0.008 J/cm2, 300 sec/wound. Each animal received two skin wounds which were photographed on days 0, 5, and 10 to determine wound closure (ImageJ). Half of the animals in each group were sacrificed on day 5 and the other half on day 10. Samples were routinely processed for histological analysis (re-epithelization, angiogenesis, granulation tissue formation, inflammation, and collagen deposition). Results: The closure of the wounds at the end of the experiment in the animals photobiostimulated each other day was more advanced than in the controls and in those treated only once, in both the macroscopic and microscopic studies. Angiogenesis was higher in both treated groups than in the control in the first study time (day 5). However, inflammation, maturation of the granulation tissue, and collagen deposition only improved when the laser was applied each other day. Conclusions: In our study, with the parameters used, PBM improved the healing of skin wounds when applied every other day and not in a single dose.


Assuntos
Terapia com Luz de Baixa Intensidade , Animais , Colágeno , Modelos Animais de Doenças , Inflamação , Terapia com Luz de Baixa Intensidade/métodos , Camundongos , Cicatrização
14.
Drugs R D ; 21(2): 189-202, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33893973

RESUMO

BACKGROUND: GNE myopathy is a rare genetic muscle disease resulting from deficiency in an enzyme critical for the biosynthesis of N-acetylneuraminic acid (Neu5Ac, sialic acid). The uncharged Neu5Ac precursor, N-acetylmannosamine (ManNAc), is under development as an orphan drug for treating GNE myopathy. METHODS: A semi-mechanistic population pharmacokinetic model was developed to simultaneously characterize plasma ManNAc and its metabolite Neu5Ac following oral administration of ManNAc to subjects with GNE myopathy. Plasma ManNAc and Neu5Ac pharmacokinetic data were obtained from two clinical studies (ClinicalTrials.gov identifiers NCT01634750, NCT02346461) and were simultaneously modeled using NONMEM. RESULTS: ManNAc and Neu5Ac plasma concentrations were obtained from 34 subjects with GNE myopathy (16 male, 18 female, median age 39.5 years). The model parameter estimates included oral absorption rate (ka) = 0.256 h-1, relative bioavailability relationship with dose (F-Dose) slope = -0.405 (where F = 1 for 6-g dose), apparent clearance (CLM/F) = 631 L/h, volume of distribution (VM/F) = 506 L, Neu5Ac elimination rate constant (kout) = 0.283 h-1, initial ManNAc to Neu5Ac conversion (SLP0) = 0.000619 (ng/mL)-1 and at steady-state (SLPSS) = 0.00334 (ng/mL)-1, with a rate-constant of increase (kinc) = 0.0287 h-1. Goodness-of-fit plots demonstrated an acceptable and unbiased fit to the plasma ManNAc and Neu5Ac concentration data. Visual predictive checks demonstrated reasonable agreement between the 5th, 50th, and 95th percentiles of the observed and simulated data. CONCLUSIONS: This population pharmacokinetic model can be used to evaluate ManNAc dosing regimens and to calculate Neu5Ac production and exposure following oral administration of ManNAc in subjects with GNE myopathy.


Assuntos
Miopatias Distais , Doenças Musculares , Adulto , Feminino , Hexosaminas , Humanos , Masculino , Ácido N-Acetilneuramínico
15.
Neurology ; 96(5): e798-e808, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33219145

RESUMO

OBJECTIVE: To characterize muscle involvement and evaluate disease severity in patients with GNE myopathy using skeletal muscle MRI and proton magnetic resonance spectroscopy (1H-MRS). METHODS: Skeletal muscle imaging of the lower extremities was performed in 31 patients with genetically confirmed GNE myopathy, including T1-weighted and short tau inversion recovery (STIR) images, T1 and T2 mapping, and 1H-MRS. Measures evaluated included longitudinal relaxation time (T1), transverse relaxation time (T2), and 1H-MRS fat fraction (FF). Thigh muscle volume was correlated with relevant measures of strength, function, and patient-reported outcomes. RESULTS: The cohort was representative of a wide range of disease progression. Contractile thigh muscle volume ranged from 5.51% to 62.95% and correlated with thigh strength (r = 0.91), the 6-minute walk test (r = 0.82), the adult myopathy assessment tool (r = 0.83), the activities-specific balance confidence scale (r = 0.65), and the inclusion body myositis functional rating scale (r = 0.62). Four stages of muscle involvement were distinguished by qualitative (T1W and STIR images) and quantitative methods: stage I: unaffected muscle (T1 = 1,033 ± 74.2 ms, T2 = 40.0 ± 1.9 ms, FF = 7.4 ± 3.5%); stage II: STIR hyperintense muscle with minimal or no fat infiltration (T1 = 1,305 ± 147 ms, T2 = 50.2 ± 3.5 ms, FF = 27.6 ± 12.7%); stage III: fat infiltration and STIR hyperintensity (T1 = 1,209 ± 348 ms, T2 = 73.3 ± 12.6 ms, FF = 57.5 ± 10.6%); and stage IV: complete fat replacement (T1 = 318 ± 39.9 ms, T2 = 114 ± 21.2 ms, FF = 85.6 ± 4.2%). 1H-MRS showed a significant decrease in intramyocellular lipid and trimethylamines between stage I and II, suggesting altered muscle metabolism at early stages. CONCLUSION: MRI biomarkers can monitor muscle involvement and determine disease severity noninvasively in patients with GNE myopathy. CLINICALTRIALSGOV IDENTIFIER: NCT01417533.


Assuntos
Miopatias Distais/diagnóstico por imagem , Metabolismo dos Lipídeos , Força Muscular , Músculo Esquelético/diagnóstico por imagem , Adulto , Idoso , Progressão da Doença , Miopatias Distais/metabolismo , Miopatias Distais/patologia , Miopatias Distais/fisiopatologia , Feminino , Músculos Isquiossurais/diagnóstico por imagem , Músculos Isquiossurais/metabolismo , Músculos Isquiossurais/patologia , Músculos Isquiossurais/fisiopatologia , Humanos , Perna (Membro) , Lipídeos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complexos Multienzimáticos/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Tamanho do Órgão , Medidas de Resultados Relatados pelo Paciente , Espectroscopia de Prótons por Ressonância Magnética , Músculo Quadríceps/diagnóstico por imagem , Músculo Quadríceps/metabolismo , Músculo Quadríceps/patologia , Índice de Gravidade de Doença , Coxa da Perna , Teste de Caminhada , Adulto Jovem
16.
Animals (Basel) ; 11(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567775

RESUMO

Our goal was to analyze the main anatomical structures of the dolphin external nose and nasal cavity from fetal developmental stages to adult. Endoscopy was used to study the common development of the external nose and the melon, and nasal mucosa. Magnetic resonance imaging (MRI) and anatomical sections were correlated with anatomical sections. Computed tomography (CT) was used to generate 3D reconstructions of the nasal bones and nasal cavities to study its development. Dissections, histological and pathological studies were carried out on the nasal mucosa to understand its function. These results were compared with the horse. Endoscopy showed an external nose with two lips and the upper lip is divided by a groove due to the nasal septum and an obstruction of right nasal cavity was diagnosed in a newborn. Two diverticula (air sacs) were found in the nasal vestibule and an incisive recess (premaxillary sac) in the nasal cavity. These findings were corroborated by 3D reconstructions of the nasal cavities, MRI, anatomical sections and dissections. The presphenoid and ethmoid bones were fused at early stages of fetal development. The ethmoid is the last bone to ossify in the nasal cavity.

17.
PLoS One ; 16(12): e0261447, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34919595

RESUMO

BACKGROUND: Defining reference intervals in experimental animal models plays a crucial role in pre-clinical studies. The hepatic parameters in healthy animals provide useful information about type and extension of hepatic damage. However, in the majority of the cases, to obtain them require an invasive techniques. Our study combines these determinations with dynamic functional test and imaging techniques to implement a non-invasive protocol for liver evaluation. The aim of the study was to determine reference intervals for hepatic function, perfusion and parenchyma attenuation with analytical and biochemical blood parameters, indocyanine green, ultrasound and computed tomography in six healthy SD rats. METHODS: Six males healthy SD rats were followed for 4 weeks. To determine hepatic function, perfusion and parenchyma attenuation analytical and biochemical blood parameters, indocyanine green, ultrasound and computed tomography were studied. Results were expressed as Means ± standard error of mean (SEM). The significance of differences was calculated by using student t-test, p < 0.05 was considered statistically significant. RESULTS: Indocyanine green clearance 5 and 10 minutes after its injection was 80.12% and 96.59%, respectively. Approximate rate of decay during the first 5 minutes after injection was 38% per minute. Hepatic perfusion evaluation with the high-frequency ultrasound was related to cardiovascular hemodynamic and renal perfusion. Portal area, hepatic artery resistance index, hepatic artery and portal peak systolic velocity and average between hepatic artery and porta was 3.41 ± 0.62 mm2, 0.57 ± 0.04 mm2/s, 693.24±102.53 mm2/s, 150.72 ± 17.80 mm2/s and 4.82 ± 0.96 mm2/s, respectively. Heart rate, cardiac output, left renal artery diammetre and renal blood flow were 331.01 ± 22.22 bpm, 75.58 ± 8.72 mL/min, 0.88 ± 0.04 mm2 and 13.65 ± 1.95 mm2/s. CT-scan hepatic average volume for each rat were 21.08±3.32, 17.57±2.76, 14.87±2.83 and 13.67±2.45 cm3 with an average attenuation coefficient of 113.51±18.08, 129,19±7.18, 141,47±1.95 y 151,67±1.2 HU. CONCLUSION: Indocyanine green and high-frequency ultrasound could be used in rats as a suitable marker of liver function. Computed tomography, through the study of raw data, help to characterize liver parenchyma, and could be a potential tool for early detection of liver parenchymal alterations and linear follow-up of patients. Further studies in rats with liver disease are necessary to verify the usefulness of these parameters.


Assuntos
Verde de Indocianina/metabolismo , Testes de Função Hepática/métodos , Fígado/metabolismo , Tecido Parenquimatoso/metabolismo , Animais , Masculino , Modelos Animais , Ratos , Ratos Sprague-Dawley , Valores de Referência , Tomografia Computadorizada por Raios X , Ultrassonografia
18.
Adv Mater ; 33(30): e2100077, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34117667

RESUMO

Deliberate and local increase of the temperature within solid tumors represents an effective therapeutic approach. Thermal therapies embrace this concept leveraging the capability of some species to convert the absorbed energy into heat. To that end, magnetic hyperthermia (MHT) uses magnetic nanoparticles (MNPs) that can effectively dissipate the energy absorbed under alternating magnetic fields. However, MNPs fail to provide real-time thermal feedback with the risk of unwanted overheating and impeding on-the-fly adjustment of the therapeutic parameters. Localization of MNPs within a tissue in an accurate, rapid, and cost-effective way represents another challenge for increasing the efficacy of MHT. In this work, MNPs are combined with state-of-the-art infrared luminescent nanothermometers (LNTh; Ag2 S nanoparticles) in a nanocapsule that simultaneously overcomes these limitations. The novel optomagnetic nanocapsule acts as multimodal contrast agents for different imaging techniques (magnetic resonance, photoacoustic and near-infrared fluorescence imaging, optical and X-ray computed tomography). Most crucially, these nanocapsules provide accurate (0.2 °C resolution) and real-time subcutaneous thermal feedback during in vivo MHT, also enabling the attainment of thermal maps of the area of interest. These findings are a milestone on the road toward controlled magnetothermal therapies with minimal side effects.


Assuntos
Meios de Contraste/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Nanocápsulas/química , Animais , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Temperatura Alta , Humanos , Hipertermia Induzida , Raios Infravermelhos , Campos Magnéticos , Magnetismo , Camundongos , Imagem Óptica , Terapia Fototérmica , Compostos de Prata/química
19.
Sci Rep ; 10(1): 10527, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601390

RESUMO

In fish, the fat content contributes to promoting the nutritional and organoleptic characteristics of the flesh, which is crucial for consumer acceptance. Methods to predict the fat in fish are important in nutritional and physiological research, where body content is traditionally determined by dissection followed by chemical analysis. However, X-ray micro-computed tomography (micro-CT) provides three-dimensional information in a non-destructive way. This work aims to characterize radiologically the fat, in situ, in a widely cultivated marine species, gilthead seabream (Sparus aurata). To validate the method changes in fat content in a control group (fed) and another group (unfed for 60 days) were assessed. Fish images were acquired on an Albira SPECT/PET/CT preclinical-scanner. Image analysis and measurements were performed using the Carestream Molecular Imaging Albira CT system in conjunction with Pmod and Amide packages. By micro-CT analysis the density values were determined for the whole fish body (- 1,000 to + 2,500 HU, Hounsfield units), and density ranges for the fat in S. aurata were established from - 115 to + 50 HU. As expected, significant differences were found between fed and starved groups at 60 days. The present study confirms the usefulness of high-resolution morphological analysis for evaluating the presence and distribution of fat in this important fish species.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Privação de Alimentos/fisiologia , Dourada , Animais , Aquicultura , Masculino , Microtomografia por Raio-X
20.
Kidney Int Rep ; 4(10): 1454-1462, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31701055

RESUMO

INTRODUCTION: Sialic acids are important contributors to the polyanionic component of the glomerular filtration barrier, which regulates permeability selectivity. Pathologic glomerular hyposialylation, associated with podocyte effacement, has been implicated in human and mouse glomerulopathies. Oral treatment with N-acetylmannosamine (ManNAc), the uncharged precursor of sialic acid, ameliorates glomerular pathology in different models of glomerular disease. METHODS: Here we explore the sialylation status of kidney biopsies obtained from 27 subjects with various glomerular diseases using lectin histochemistry. RESULTS: We identified severe glomerular hyposialylation in 26% of the biopsies. These preliminary findings suggest that this condition may occur relatively frequently and may be a novel target for therapy. We describe the background, rationale, and design of a phase 1 study to test safety, tolerability, and pharmacokinetics of ManNAc in subjects with primary podocyte diseases. CONCLUSION: We recently demonstrated that ManNAc was safe and well tolerated in a first-in-human phase 1 study in subjects with UDP-N-acetylglucosamine (GlcNAc) 2-epimerase/ManNAc kinase (GNE) myopathy, a disorder of impaired sialic acid synthesis. Using previous preclinical and clinical data, we propose to test ManNAc therapy for subjects with primary glomerular diseases. Even though the exact mechanisms, affected cell types, and pathologic consequences of glomerular hyposialylation need further study, treatment with this physiological monosaccharide could potentially replace or supplement existing glomerular diseases therapies.

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