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1.
Oral Maxillofac Surg ; 28(2): 809-818, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38261079

RESUMO

PURPOSE: To evaluate the clinical and aesthetic outcome of percutaneous injection of sclerosant agents to treat head and neck cystic malformations (HNCM) and to assess their recurrence rate based on histology and site. METHODS: Fifty-four subjects (mean age 46 years) with HNCM treated by percutaneous injection of sclerosant agents between January and December 2017 were included. Imaging and clinical data before and after the procedure were collected. Quality of Life Index, Pain Visual Analogue Scale, and Aesthetic Scale scores were measured to assess clinical and aesthetic outcomes. A size reduction of ≥ 70% assessed through the visual scale was considered significant. RESULTS: Of the 54 HNCM, there were 26 (48%) lymphatic malformations (LM), 13 (24%) salivary epithelial duct cysts of the parotid gland, 12 (22%) salivary mucoceles, and 3 (5%) branchial cysts. A significant size reduction and a satisfactory clinical-aesthetic outcome were observed in all types of LM. The number of reinterventions was significantly associated with the number of lesions (p < 0.001). The lowest number of interventions was observed in macrocystic lymphatic malformations (average of 1.2 interventions). All salivary epithelial duct cysts showed a significant reduction in size, a satisfactory clinical-aesthetic outcome, and an average of 1.16 interventions per patient. Mucoceles had a worse response, with only 3/14 patients showing a satisfactory and long-lasting clinical outcome (average of 1.16 interventions). Treatment of branchial cysts showed the worst outcome with a limited clinical response (3/3). CONCLUSION: Percutaneous injection of sclerosant agents may be considered as a first-line treatment for LM and salivary epithelial duct cysts.


Assuntos
Cistos , Anormalidades Linfáticas , Soluções Esclerosantes , Humanos , Soluções Esclerosantes/uso terapêutico , Soluções Esclerosantes/administração & dosagem , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Adolescente , Cistos/tratamento farmacológico , Anormalidades Linfáticas/tratamento farmacológico , Anormalidades Linfáticas/terapia , Criança , Idoso , Adulto Jovem , Resultado do Tratamento , Pré-Escolar , Escleroterapia/métodos , Mucocele/tratamento farmacológico , Branquioma/tratamento farmacológico , Estética
3.
Arch. bronconeumol. (Ed. impr.) ; 59(7): 418-426, jul. 2023. tab, graf
Artigo em Inglês | IBECS | ID: ibc-223087

RESUMO

Introduction: This study aimed to evaluate a potential relationship between the diffusing capacity of the lung for carbon monoxide (DLCO) and the aggressiveness of lung adenocarcinoma (ADC). Methods: Patients who underwent radical surgery for lung ADC between 2001 and 2018 were retrospectively reviewed. DLCO values were dichotomized into DLCOlow (<80% of predicted) and DLCOnormal (≥80%). Relationships between DLCO and ADC histopathological features, clinical features, as well as with overall survival (OS), were evaluated. Results: Four-hundred and sixty patients were enrolled, of which 193 (42%) were included in the DLCOlow group. DLCOlow was associated with smoking status, low FEV1, micropapillary and solid ADC, tumour grade 3, high tumour lymphoid infiltrate and presence of tumour desmoplasia. In addition, DLCO values were higher in low-grade ADC and progressively decreased in intermediate and high-grade ADC (p=0.024). After adjusting for clinical variables, at multivariable logistic regression analysis, DLCOlow still showed a significant correlation with high lymphoid infiltrate (p=0.017), presence of desmoplasia (p=0.065), tumour grade 3 (p=0.062), micropapillary and solid ADC subtypes (p=0.008). To exclude the association between non-smokers and well-differentiated ADC, the relationship between DLCO and histopathological ADC patterns was confirmed in the subset of 377 former and current smokers (p=0.021). At univariate analysis, gender, DLCO, FEV1, ADC histotype, tumour grade, stage, pleural invasion, tumour necrosis, tumour desmoplasia, lymphatic and blood invasion were significantly related with OS. At multivariate analysis, only gender (p<0.001), tumour stage (p<0.001) and DLCO (p=0.050) were significantly related with the OS. Conclusions: We found a relationship between DLCO and ADC patterns as well as with tumour grade, tumour lymphoid infiltrate and desmoplasia, suggesting that lung damage may be associated with tumour aggressiveness. (AU)


Assuntos
Humanos , Adenocarcinoma de Pulmão , Neoplasias Pulmonares/cirurgia , Monóxido de Carbono , Capacidade de Difusão Pulmonar , Estudos Retrospectivos , Pulmão
4.
Arch Bronconeumol ; 59(7): 418-426, 2023 Jul.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37032196

RESUMO

INTRODUCTION: This study aimed to evaluate a potential relationship between the diffusing capacity of the lung for carbon monoxide (DLCO) and the aggressiveness of lung adenocarcinoma (ADC). METHODS: Patients who underwent radical surgery for lung ADC between 2001 and 2018 were retrospectively reviewed. DLCO values were dichotomized into DLCOlow (<80% of predicted) and DLCOnormal (≥80%). Relationships between DLCO and ADC histopathological features, clinical features, as well as with overall survival (OS), were evaluated. RESULTS: Four-hundred and sixty patients were enrolled, of which 193 (42%) were included in the DLCOlow group. DLCOlow was associated with smoking status, low FEV1, micropapillary and solid ADC, tumour grade 3, high tumour lymphoid infiltrate and presence of tumour desmoplasia. In addition, DLCO values were higher in low-grade ADC and progressively decreased in intermediate and high-grade ADC (p=0.024). After adjusting for clinical variables, at multivariable logistic regression analysis, DLCOlow still showed a significant correlation with high lymphoid infiltrate (p=0.017), presence of desmoplasia (p=0.065), tumour grade 3 (p=0.062), micropapillary and solid ADC subtypes (p=0.008). To exclude the association between non-smokers and well-differentiated ADC, the relationship between DLCO and histopathological ADC patterns was confirmed in the subset of 377 former and current smokers (p=0.021). At univariate analysis, gender, DLCO, FEV1, ADC histotype, tumour grade, stage, pleural invasion, tumour necrosis, tumour desmoplasia, lymphatic and blood invasion were significantly related with OS. At multivariate analysis, only gender (p<0.001), tumour stage (p<0.001) and DLCO (p=0.050) were significantly related with the OS. CONCLUSIONS: We found a relationship between DLCO and ADC patterns as well as with tumour grade, tumour lymphoid infiltrate and desmoplasia, suggesting that lung damage may be associated with tumour aggressiveness.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Monóxido de Carbono , Estudos Retrospectivos , Pulmão , Neoplasias Pulmonares/cirurgia , Capacidade de Difusão Pulmonar
5.
Sci Rep ; 13(1): 4462, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932122

RESUMO

Experimental in-vivo animal models are key tools to investigate the pathogenesis of lung disease and to discover new therapeutics. Histopathological and biochemical investigations of explanted lung tissue are currently considered the gold standard, but they provide space-localized information and are not amenable to longitudinal studies in individual animals. Here, we present an imaging procedure that uses micro-CT to extract morpho-functional indicators of lung pathology in a murine model of lung fibrosis. We quantified the decrease of lung ventilation and measured the antifibrotic effect of Nintedanib. A robust structure-function relationship was revealed by cumulative data correlating micro-CT with histomorphometric endpoints. The results highlight the potential of in-vivo micro-CT biomarkers as novel tools to monitor the progression of inflammatory and fibrotic lung disease and to shed light on the mechanism of action of candidate drugs. Our platform is also expected to streamline translation from preclinical studies to human patients.


Assuntos
Fibrose Pulmonar , Humanos , Animais , Camundongos , Fibrose Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologia , Microtomografia por Raio-X/métodos , Modelos Animais de Doenças , Pulmão/patologia , Biomarcadores , Fibrose
6.
Front Oncol ; 13: 1132564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36925919

RESUMO

Introduction: The Notch intracellular domain (NICD) and its ligands Jagged-1(Jag1), Delta-like ligand (DLL-3) and DLL4 play an important role in neoangiogenesis. Previous studies suggest a correlation between the tissue levels of NICD and response to therapy with bevacizumab in colorectal cancer (CRC). Another marker that may predict outcome in CRC is radiomics of liver metastases. The aim of this study was to investigate the expression of NICD and its ligands and the role of radiomics in the selection of treatment-naive metastatic CRC patients receiving bevacizumab. Methods: Immunohistochemistry (IHC) for NICD, Jag1 and E-cadherin was performed on the tissue microarrays (TMAs) of 111 patients with metastatic CRC treated with bevacizumab and chemotherapy. Both the intensity and the percentage of stained cells were evaluated. The absolute number of CD4+ and CD8+ lymphocytes was counted in three different high-power fields and the mean values obtained were used to determine the CD4/CD8 ratio. The positivity of tumor cells to DLL3 and DLL4 was studied. The microvascular density (MVD) was assessed in fifteen cases by counting the microvessels at 20x magnification and expressed as MVD score. Abdominal CT scans were retrieved and imported into a dedicated workstation for radiomic analysis. Manually drawn regions of interest (ROI) allowed the extraction of radiomic features (RFs) from the tumor. Results: A positive association was found between NICD and Jag1 expression (p < 0.001). Median PFS was significantly shorter in patients whose tumors expressed high NICD and Jag1 (6.43 months vs 11.53 months for negative cases; p = 0.001). Those with an MVD score ≥5 (CD31-high, NICD/Jag1 positive) experienced significantly poorer survival. The radiomic model developed to predict short and long-term survival and PFS yielded a ROC-AUC of 0.709; when integrated with clinical and histopathological data, the integrated model improved the predictive score (ROC-AUC of 0.823). Discussion: These results show that high NICD and Jag1 expression are associated with progressive disease and early disease progression to anti VEGF-based therapy; the preliminary radiomic analyses show that the integration of quantitative information with clinical and histological data display the highest performance in predicting the outcome of CRC patients.

7.
Am J Physiol Lung Cell Mol Physiol ; 324(2): L211-L227, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36625471

RESUMO

The development of new drugs for idiopathic pulmonary fibrosis strongly relies on preclinical experimentation, which requires the continuous improvement of animal models and integration with in vivo imaging data. Here, we investigated the lung distribution of bleomycin (BLM) associated with the indocyanine green (ICG) dye by fluorescence imaging. A long-lasting lung retention (up to 21 days) was observed upon oropharyngeal aspiration (OA) of either ICG or BLM + ICG, with significantly more severe pulmonary fibrosis, accompanied by the progressive appearance of emphysema-like features, uniquely associated with the latter combination. More severe and persistent lung fibrosis, together with a progressive air space enlargement uniquely associated with the BLM + ICG group, was confirmed by longitudinal micro-computed tomography (CT) and histological analyses. Multiple inflammation and fibrosis biomarkers were found to be increased in the bronchoalveolar lavage fluid of BLM- and BLM + ICG-treated animals, but with a clear trend toward a much stronger increase in the latter group. Similarly, in vitro assays performed on macrophage and epithelial cell lines revealed a significantly more marked cytotoxicity in the case of BLM + ICG-treated mice. Also unique to this group was the synergistic upregulation of apoptotic markers both in lung sections and cell lines. Although the exact mechanism underlying the more intense lung fibrosis phenotype with emphysema-like features induced by BLM + ICG remains to be elucidated, we believe that this combination treatment, whose overall effects more closely resemble the human disease, represents a valuable alternative model for studying fibrosis development and for the identification of new antifibrotic compounds.


Assuntos
Enfisema , Fibrose Pulmonar Idiopática , Enfisema Pulmonar , Humanos , Camundongos , Animais , Bleomicina , Microtomografia por Raio-X , Pulmão/diagnóstico por imagem , Pulmão/patologia , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/patologia , Líquido da Lavagem Broncoalveolar , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Fibrose Pulmonar Idiopática/patologia , Enfisema/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
8.
Eur Radiol ; 33(4): 2975-2984, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36512046

RESUMO

OBJECTIVES: To test reproducibility and predictive value of a simplified score for assessment of extraprostatic tumor extension (sEPE grade). METHODS: Sixty-five patients (mean age ± SD, 67 years ± 6.3) treated with radical prostatectomy for prostate cancer who underwent 1.5-Tesla multiparametric magnetic resonance imaging (mpMRI) 6 months before surgery were enrolled. sEPE grade was derived from mpMRI metrics: curvilinear contact length > 15 mm (CCL) and capsular bulging/irregularity. The diameter of the index lesion (dIL) was also measured. Evaluations were independently performed by seven radiologists, and inter-reader agreement was tested by weighted Cohen K coefficient. A nested (two levels) Monte Carlo cross-validation was used. The best cut-off value for dIL was selected by means of the Youden J index to classify values into a binary variable termed dIL*. Logistic regression models based on sEPE grade, dIL, and clinical scores were developed to predict pathologic EPE. Results on validation set were assessed by the main metrics of the receiver operating characteristics curve (ROC) and by decision curve analysis (DCA). Based on our findings, we defined and tested an alternative sEPE grade formulation. RESULTS: Pathologic EPE was found in 31/65 (48%) patients. Average κw was 0.65 (95% CI 0.51-0.79), 0.66 (95% CI 0.48-0.84), 0.67 (95% CI 0.50-0.84), and 0.43 (95% CI 0.22-0.63) for sEPE grading, CLL ≥ 15 mm, dIL*, and capsular bulging/irregularity, respectively. The highest diagnostic yield in predicting EPE was obtained by combining both sEPE grade and dIL*(ROC-AUC 0.81). CONCLUSIONS: sEPE grade is reproducible and when combined with the dIL* accurately predicts extraprostatic tumor extension. KEY POINTS: • Simple and reproducible mpMRI semi-quantitative scoring system for extraprostatic tumor extension. • sEPE grade accurately predicts extraprostatic tumor extension regardless of reader expertise. • Accurate pre-operative staging and risk stratification for optimized patient management.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Próstata/patologia , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Prostatectomia/métodos , Estudos Retrospectivos
9.
Respir Res ; 23(1): 308, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369209

RESUMO

Idiopathic pulmonary fibrosis, the archetype of pulmonary fibrosis (PF), is a chronic lung disease of a poor prognosis, characterized by progressively worsening of lung function. Although histology is still the gold standard for PF assessment in preclinical practice, histological data typically involve less than 1% of total lung volume and are not amenable to longitudinal studies. A miniaturized version of computed tomography (µCT) has been introduced to radiologically examine lung in preclinical murine models of PF. The linear relationship between X-ray attenuation and tissue density allows lung densitometry on total lung volume. However, the huge density changes caused by PF usually require manual segmentation by trained operators, limiting µCT deployment in preclinical routine. Deep learning approaches have achieved state-of-the-art performance in medical image segmentation. In this work, we propose a fully automated deep learning approach to segment right and left lung on µCT imaging and subsequently derive lung densitometry. Our pipeline first employs a convolutional network (CNN) for pre-processing at low-resolution and then a 2.5D CNN for higher-resolution segmentation, combining computational advantage of 2D and ability to address 3D spatial coherence without compromising accuracy. Finally, lungs are divided into compartments based on air content assessed by density. We validated this pipeline on 72 mice with different grades of PF, achieving a Dice score of 0.967 on test set. Our tests demonstrate that this automated tool allows for rapid and comprehensive analysis of µCT scans of PF murine models, thus laying the ground for its wider exploitation in preclinical settings.


Assuntos
Aprendizado Profundo , Fibrose Pulmonar , Animais , Camundongos , Fibrose Pulmonar/diagnóstico por imagem , Microtomografia por Raio-X , Modelos Animais de Doenças , Densitometria
10.
Sci Rep ; 12(1): 9695, 2022 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690601

RESUMO

Micro-computed tomography (CT) imaging provides densitometric and functional assessment of lung diseases in animal models, playing a key role either in understanding disease progression or in drug discovery studies. The generation of reliable and reproducible experimental data is strictly dependent on a system's stability. Quality controls (QC) are essential to monitor micro-CT performance but, although QC procedures are standardized and routinely employed in clinical practice, detailed guidelines for preclinical imaging are lacking. In this work, we propose a routine QC protocol for in vivo micro-CT, based on three commercial phantoms. To investigate the impact of a detected scanner drift on image post-processing, a retrospective analysis using twenty-two healthy mice was performed and lung density histograms used to compare the area under curve (AUC), the skewness and the kurtosis before and after the drift. As expected, statistically significant differences were found for all the selected parameters [AUC 532 ± 31 vs. 420 ± 38 (p < 0.001); skewness 2.3 ± 0.1 vs. 2.5 ± 0.1 (p < 0.001) and kurtosis 4.2 ± 0.3 vs. 5.1 ± 0.5 (p < 0.001)], confirming the importance of the designed QC procedure to obtain a reliable longitudinal quantification of disease progression and drug efficacy evaluation.


Assuntos
Pneumopatias , Pulmão , Animais , Progressão da Doença , Pulmão/diagnóstico por imagem , Camundongos , Controle de Qualidade , Estudos Retrospectivos , Microtomografia por Raio-X/métodos
11.
PLoS One ; 17(6): e0270005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35704641

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with no curative pharmacological treatment. The most used animal model of IPF for anti-fibrotic drug screening is bleomycin (BLM)-induced lung fibrosis. However, several issues have been reported: the balance among disease resolution, an appropriate time window for therapeutic intervention and animal welfare remain critical aspects yet to be fully elucidated. In this study, C57Bl/6 male mice were treated with BLM via oropharyngeal aspiration (OA) following either double or triple administration. The fibrosis progression was longitudinally assessed by micro-CT every 7 days for 4 weeks after BLM administration. Quantitative micro-CT measurements highlighted that triple BLM administration was the ideal dose regimen to provoke sustained lung fibrosis up to 28 days. These results were corroborated with lung histology and Bronchoalveolar Lavage Fluid cells. We have developed a mouse model with prolonged lung fibrosis enabling three weeks of a curative therapeutic window for the screening of putative anti-fibrotic drugs. Moreover, we have demonstrated the pivotal role of longitudinal micro-CT imaging in reducing the number of animals required per experiment in which each animal can be its own control. This approach permits a valuable decrease in costs and time to develop disease animal models.


Assuntos
Bleomicina , Fibrose Pulmonar Idiopática , Animais , Bleomicina/farmacologia , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tecnologia , Microtomografia por Raio-X
12.
Insights Imaging ; 13(1): 6, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35032230

RESUMO

Interstitial lung abnormalities (ILAs) represent radiologic abnormalities incidentally detected on chest computed tomography (CT) examination, potentially related to interstitial lung diseases (ILD). Numerous studies have demonstrated that ILAs are associated with increased risk of progression toward pulmonary fibrosis and mortality. Some radiological patterns have been proven to be at a higher risk of progression. In this setting, the role of radiologists in reporting these interstitial abnormalities is critical. This review aims to discuss the most recent advancements in understanding this radiological entity and the open issues that still prevent the translation from theory to practice, emphasizing the importance of ILA recognition and adequately reporting in clinical practice.

13.
Arch Biochem Biophys ; 714: 109079, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34748734

RESUMO

Collagen dehydration is an unavoidable damaging process that causes the lack of fibers' physical properties and it is usually irreversible. However, the identification of low hydration conditions that permit a recovering of initial collagen features after a rehydration treatment is particularly of interest. Monitoring structural changes by means of MD simulations, we investigated the hydration-dehydration-rehydration cycle of two microfibril models built on different fragments of the sequence of rat tail collagen type I. The microfibrils have different hydropathic features, to investigate the influence of amino acid composition on the whole process. We showed that with low hydration at a level corresponding to the first shell, microfibril gains in compactness and tubularity. Crucially, some water molecules remain trapped inside the fibrils, allowing, by rehydrating, a recovery of the initial collagen structural features. Water rearranges in cluster around the protein, and its first layer is more anchored to the surface. However, these changes in distribution and mobility in low hydration conditions get back with rehydration.


Assuntos
Colágeno/química , Água/química , Sequência de Aminoácidos , Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação Proteica
14.
Am J Physiol Lung Cell Mol Physiol ; 321(6): L1206-L1214, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34786984

RESUMO

Micro-computed tomography (micro-CT) imaging is an emerging technology with many applications in small animals, for example, the study of pulmonary diseases, although clear guidelines and critical mass of evidence are still missing in the preclinical literature. The neonatal rabbit is a valuable model for studying pulmonary development. However, the longitudinal monitoring of lung function by micro-CT can be challenging. Distinctive datasets corresponding to the end-inspiration and end-expiration phases need to be generated and analyzed to derive lung-functional parameters. The quality of CT scans and the reliability of parameters obtained remain highly dependent on the anesthesia protocol used. Three different anesthetic protocols were tested. The combination of dexmedetomidine 0.25 mg/kg injected intraperitoneally followed by 1% isoflurane was found to facilitate CT imaging at 4 and 11 days after birth. Contrarily, isoflurane and ketamine-xylazine were found unsuitable and thus not investigated further. Total lung volumes significantly increased at day 11 compared with baseline in both respiratory phases, whereas lung tissue remained constant. As expected, functional residual capacity, air-to-tissue ratio, and minute ventilation were significantly increased at day 11 in each animal. Those parameters were correlated with inspiratory capacity, compliance, elastance, and resistance of both respiratory system and tissue component, as measured by flexiVent. Lung development was also evaluated by histomorphometric analyses. In conclusion, we have identified a safe and suitable anesthesia protocol for micro-CT imaging in neonatal rabbits. Moreover, the possibility to longitudinally measure lung function in the same subject dramatically reduced the intraexperimental variability.


Assuntos
Anestesia/métodos , Anestésicos/farmacologia , Pulmão/fisiologia , Microtomografia por Raio-X/métodos , Animais , Animais Recém-Nascidos , Capacidade Residual Funcional , Pulmão/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Coelhos , Testes de Função Respiratória
15.
Biophys Chem ; 253: 106224, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31351390

RESUMO

Self-assembly of rat tail collagen type I was investigated by means of turbidity measurements and molecular dynamics simulations. Turbidity curves collected at different pH values show that the rate of aggregation was not linear in dependence from pH, with the fastest kinetics at pH 5.0 and the lowest at neutral pH. MD simulations were carried out on two regions with different hydropathicity, monitoring the aggregation of up to four staggered tropocollagen fragments at different ionic strength. At physiological conditions, association of lowly charged regions occurs more easily than for highly charged ones, the latter seeming to aggregate in a sequential way. The first contacts indicate for both regions that the driving force is hydrophobic, the electrostatic contribution becoming relevant at short distance. The direct inter-tropocollagen H-bonds confirm that fibrillogenesis is driven by loss of surface water from the monomers and involves in large percentage hydroxyproline residues. Low ionic strength dynamics leads to the formation of incorrect assemblies, driven by not shielded pairwise charge interactions.


Assuntos
Colágeno Tipo I/síntese química , Simulação de Dinâmica Molecular , Animais , Colágeno Tipo I/química , Ligação de Hidrogênio , Ratos , Espectrofotometria Ultravioleta , Cauda/química
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