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1.
Analyst ; 148(2): 278-285, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36525038

RESUMEN

Urothelial bladder carcinoma (BC) is primarily diagnosed with a subjective examination of biopsies by histopathologists, but accurate diagnosis remains time-consuming and of low diagnostic accuracy, especially for low grade non-invasive BC. We propose a novel approach for high-throughput BC evaluation by combining infrared (IR) microscopy of bladder sections with machine learning (partial least squares-discriminant analysis) to provide an automated prediction of the presence of cancer, invasiveness and grade. Cystoscopic biopsies from 50 patients with clinical suspicion of BC were histologically examined to assign grades and stages. Adjacent tissue cross-sections were IR imaged to provide hyperspectral datasets and cluster analysis segregated IR images to extract the average spectra of epithelial and subepithelial tissues. Discriminant models, which were validated using repeated random sampling double cross-validation, showed sensitivities (AUROC) ca. 85% (0.85) for the identification of cancer in epithelium and subepithelium. The diagnosis of non-invasive and invasive cases showed sensitivity values around 80% (0.84-0.85) and 76% (0.73-0.80), respectively, while the identification of low and high grade BC showed higher sensitivity values 87-88% (0.91-0.92). Finally, models for the discrimination between cancers with different invasiveness and grades showed more modest AUROC values (0.67-0.72). This proves the high potential of IR imaging in the development of ancillary platforms to screen bladder biopsies.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Carcinoma de Células Transicionales/patología , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/patología , Vejiga Urinaria/patología , Aprendizaje Automático , Diagnóstico por Imagen , Invasividad Neoplásica
2.
Int J Mol Sci ; 24(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37894812

RESUMEN

The incidence of thyroid nodules (TNs) is estimated at 36.5% and 23% in females and males, respectively. A single thyroid nodule is usually detected during ultrasound assessment in patients with symptoms of thyroid dysfunction or neck mass. TNs are classified as benign tumours (non-malignant hyperplasia), benign neoplasms (e.g., adenoma, a non-invasive follicular tumour with papillary nuclear features) or malignant carcinomas (follicular cell-derived or C-cell derived). The differential diagnosis is based on fine-needle aspiration biopsies and cytological assessment (which is burdened with the bias of subjectivity). Raman spectroscopy (RS) is a laser-based, semiquantitative technique which shows for oscillations of many chemical groups in one label-free measurement. RS, through the assessment of chemical content, gives insight into tissue state which, in turn, allows for the differentiation of disease on the basis of spectral characteristics. The purpose of this study was to report if RS could be useful in the differential diagnosis of TN. The Web of Science, PubMed, and Scopus were searched from the beginning of the databases up to the end of June 2023. Two investigators independently screened key data using the terms "Raman spectroscopy" and "thyroid". From the 4046 records found initially, we identified 19 studies addressing the differential diagnosis of TNs applying the RS technique. The lasers used included 532, 633, 785, 830, and 1064 nm lines. The thyroid RS investigations were performed at the cellular and/or tissue level, as well as in serum samples. The accuracy of papillary thyroid carcinoma detection is approx. 90%. Furthermore, medullary, and follicular thyroid carcinoma can be detected with up to 100% accuracy. These results might be biased with low numbers of cases in some research and overfitting of models as well as the reference method. The main biochemical changes one can observe in malignancies are as follows: increase of protein, amino acids (like phenylalanine, tyrosine, and tryptophan), and nucleic acid content in comparison with non-malignant TNs. Herein, we present a review of the literature on the application of RS in the differential diagnosis of TNs. This technique seems to have powerful application potential in thyroid tumour diagnosis.


Asunto(s)
Adenocarcinoma Folicular , Neoplasias de la Tiroides , Nódulo Tiroideo , Masculino , Femenino , Humanos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Espectrometría Raman , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Adenocarcinoma Folicular/patología
3.
Gynecol Endocrinol ; 36(5): 460-464, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32037914

RESUMEN

The article presents a case of a 28-year-old woman with so-called morulosis - a form of squamous metaplasia of the endometrium, which may mimic malignancy. The term 'morulosis' indicates extensive squamous mulberry-like metaplasia, which in a large part or nearly entirely affects endometrium, whereas in turn, benign squamous metaplasia or single morules, refers to a limited, usually small regional pathology of endometrium. Because the endometrial glands and stroma gradually undergo the process of squamous metaplasia, in a scanty biopsy material the picture may lead to overdiagnosis. In the epithelioid regions small inactive glands with an immunofenotype different from the remaining endometrium might be observed. So far 21 cases have been reported in English literature. The patients (age 19-45) had presented with abnormal bleeding, infertility or after hormonal therapy. The mechanism of the extensive squamous metaplasia of endometrium is still not clear. The prevailing view holds that morulosis appears to be a result of hormonal imbalance. To shed light on possible pathogenic background of morulosis, we present a case of particularly severe extensive squamous metaplasia of the endometrium (morulosis).


Asunto(s)
Endometrio/patología , Enfermedades Uterinas/patología , Adulto , Femenino , Humanos , Infertilidad Femenina/etiología , Metaplasia , Enfermedades Uterinas/complicaciones
4.
Molecules ; 25(1)2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31935974

RESUMEN

This work focused on a detailed assessment of lung tissue affected by metastasis of breast cancer. We used large-area chemical scanning implemented in Fourier transform infrared (FTIR) spectroscopic imaging supported with classical histological and morphological characterization. For the first time, we differentiated and defined biochemical changes due to metastasis observed in the lung parenchyma, atelectasis, fibrous, and muscle cells, as well as bronchi ciliate cells, in a qualitative and semi-quantitative manner based on spectral features. The results suggested that systematic extracellular matrix remodeling with the progress of the metastasis process evoked a decrease in the fraction of the total protein in atelectasis, fibrous, and muscle cells, as well as an increase of fibrillar proteins in the parenchyma. We also detected alterations in the secondary conformations of proteins in parenchyma and atelectasis and changes in the level of hydroxyproline residues and carbohydrate moieties in the parenchyma. The results indicate the usability of FTIR spectroscopy as a tool for the detection of extracellular matrix remodeling, thereby enabling the prediction of pre-metastatic niche formation.


Asunto(s)
Neoplasias de la Mama/patología , Matriz Extracelular , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Espectroscopía Infrarroja por Transformada de Fourier , Animales , Modelos Animales de Enfermedad , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Femenino , Humanos , Inmunohistoquímica , Ratones
5.
Children (Basel) ; 11(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38671620

RESUMEN

BACKGROUND: DICER1, a cancer predisposition syndrome (CPS), seems to escape timely diagnosis in pediatric patients. Case report 1: A 16-year-old female patient was referred to the endocrinology ward due to a large goiter. Her medical history indicated normal sexual maturation, with menarche occurring at 13.5 years. Over the past 2.5 years, she had developed pronounced androgenic symptoms, including a deepened male voice; facial, back, and neckline acne; hirsutism; and menstrual irregularities leading to secondary amenorrhea. A thyroid ultrasound identified a multinodular goiter (MNG) with cystic-solid lesions containing calcifications. An abdominal ultrasound identified a 5.7 × 6.9 cm solid mass in the right adnexal region, displacing the uterus to the left. Histopathological examination confirmed a Sertoli-Leydig cell tumor. The patient was subjected to a total thyroidectomy. Histopathology revealed benign follicular cell-derived neoplasms. Thyroid follicular nodular disease (TFND) was diagnosed bilaterally. DNA analysis using NGS, confirmed via the Sanger method, revealed a pathogenic heterozygotic variant c.2953C>T [p.Gln985*] in exon 18 of the DICER1 gene. Case report 2: A 12-year-old male patient was admitted to the pediatric surgery unit due to a 33 mL goiter. A month prior to his admission, the patient discovered a palpable nodule in his neck, accompanied by hoarseness. An ultrasound revealed MNG. Molecular analysis revealed a pathogenic heterozygotic variant c.2782C>T [p.Gln928*] in exon 17 of the DICER1 gene. Subsequently, a total thyroidectomy was performed, and histopathological examination revealed TFND bilaterally. CONCLUSIONS: Recent advances in genetic evaluation and in histological approaches indicate that MNG/TFND, although rare in the pediatric population, when accompanied by characteristic ultrasound and histopathological features, and by additional features such as androgenization, may warrant assessment also of the DICER1 gene within CPS molecular panel screening.

6.
Biochim Biophys Acta Mol Basis Dis ; 1869(8): 166840, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37558006

RESUMEN

The process of metastasis is complex and often impossible to be recognized in conventional clinical diagnosis. Lymph node metastasis (LNM) of bladder carcinoma (BC) is often associated with muscle-invasive tumors. To prevent and recognize LNM, the standard treatment includes radical cystectomy with lymph node dissection and histological examination. Here, we propose infrared (IR) microscopy as a tool for the prediction of LNM. For this purpose, IR images of bladder biopsies from patients with diagnosed non-metastatic early (E BC) and advanced (A BC), as well as metastatic advanced (M BC) bladder cancer were first collected. Furthermore, this dataset was complemented with images of the secondary tumors from the lymph nodes (M LN) of the M BC patients. Unsupervised clustering was used to extract tissue structures from IR images to create a data set comprising 382 IR spectra of non-metastatic bladder tumors and 241 metastatic ones. Based on that, we next established discrimination models using PLS-DA with repeated random sampling double cross-validation, and permutation test to perform the classification. The accuracy of BC metastasis prediction from IR bladder biopsies was 83 % and 78 % for early and advanced BC, respectively, herein demonstrating a proof-of-concept IR detection of BC metastasis. The analysis of spectral profiles additionally showed molecular composition similarity between metastatic bladder and lymph node tumors. We also determined spectral biomarkers of LNM that are associated with sugar metabolism, remodeling of extracellular matrix, and morphological features of cancer cells. Our approach can improve clinical decision-making in urological oncology.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Vejiga Urinaria/metabolismo , Carcinoma de Células Transicionales/metabolismo , Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/cirugía , Metástasis Linfática/patología , Análisis de Fourier , Neoplasias de la Vejiga Urinaria/patología
7.
Front Endocrinol (Lausanne) ; 14: 1172823, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124746

RESUMEN

Background: Follicular cell-derived thyroid carcinoma represents the vast majority of paediatric thyroid cancers (TCs). Papillary thyroid carcinoma (PTC) accounts for over 90% of all childhood TC cases, and its incidence in paediatric patients is increasing. The objective of this follow-up study was to present the outcome of ultrasound (US) and laboratory monitoring of paediatric patients with autoimmune thyroiditis (AIT) prior to the development of PTC. Patients and methods: This prospective study included 180 children and adolescents (132 females; 73.3%) with a suspicion of thyroid disorder referred to the Outpatient Endocrine Department. The patients were divided into four groups: 1) 28 patients with a mean age of 10.7 [standard deviation (SD), 3.1] y, in whom PTC was detected during the active surveillance of AIT [AIT(+), PTC(+) follow up (F)]; 2) 18 patients with a mean age of 12.8 (SD, 3.4) y, in whom PTC and AIT were detected upon admission (A) [AIT(+), PTC(+) A]; 3) 45 patients with a mean age of 13.0 (SD, 3.4) y, in whom PTC was detected upon admission and AIT was excluded [AIT(-), PTC(+) A]; and 4) an age- and sex-matched control group of 89 patients with AIT and with a mean age of 9.4 (SD, 3.0) y. The analysis included clinical, US, and laboratory assessment results of children on admission (groups 1-4) and during follow-up (groups 1 and 4) in the Paediatric Endocrine Outpatient Department. Results: Upon admission of those in group 1, the US evaluation revealed a hypoechogenic thyroid gland in 12 and an irregular normoechogenic gland in 16 patients. US monitoring revealed an increase in thyroid echogenicity and an increased irregularity of the thyroid structure during the follow-up period of all of the patients from group 1. Such changes were not noticed in group 4. PTC was diagnosed at the mean time of 3.6 y (3 mo-9 y) since AIT confirmation in group 1. The mean maximum PTC diameter as per the US was significantly smaller in group 1 than in groups 2 and 3 [13.2 (10.8) mm vs. 22.2 (12.8) and 22.05 (15.4) mm]. Fewer patients in group 1 were referred to 131I than in groups 2 and 3 (71.4% vs. 94.4 and 93.3%). Interestingly, significant differences were observed in the thyroglobulin antibody (TgAb)/thyroid peroxidase antibody (TPOAb) ratio between groups 2 and 3, as opposed to group 4, at the beginning of observation [15.3 (27.6) and 3.5 (8.8] vs. 0.77 (1.9)]. In group 1, after the follow-up, an increase in the TgAb/TPOAb ratio was observed [1.2 (9.8) to 5.2 (13.5)]. There were no significant differences between groups 1-3 in labeling index Ki67, lymph nodes metastasis, extrathyroidal extension, and angioinvasion. There were no associations between thyroid-stimulating hormone, TgAb, and the extent of the disease. Conclusion: The use of thyroid US focused on the search for developing tumours in the routine follow-up of patients with AIT may not only help in the early detection of thyroid malignancies that are not clinically apparent but may also influence the invasiveness of oncological therapy and reduce the future side effects of 131I therapy. We propose that the repeat evaluation of TPOAb and TgAb warrants further exploration as a strategy to determine TC susceptibility in paediatric patients with AIT in larger multicentre studies.


Asunto(s)
Adenocarcinoma Folicular , Enfermedad de Hashimoto , Neoplasias de la Tiroides , Tiroiditis Autoinmune , Femenino , Adolescente , Humanos , Niño , Tiroiditis Autoinmune/complicaciones , Estudios de Seguimiento , Radioisótopos de Yodo , Cáncer Papilar Tiroideo/diagnóstico por imagen , Cáncer Papilar Tiroideo/complicaciones , Estudios Prospectivos , Neoplasias de la Tiroides/patología , Enfermedad de Hashimoto/complicaciones , Ultrasonografía/efectos adversos
8.
Front Endocrinol (Lausanne) ; 14: 1170971, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37274328

RESUMEN

Background: Papillary thyroid carcinoma (PTC) often coincides with autoimmune thyroiditis (AIT); whether this association is incidental or causal remains debated. Objective: To evaluate the ultrasonographic, laboratory, and histopathological features of PTC in paediatric patients with and without AIT and its relationship to puberty. Design: A retrospective cohort study. Patients and methods: A retrospective analysis of medical records of 90 patients (69; 76.7% females). The mean age at PTC diagnosis was 13.8 years [range 6-18]. All patients were evaluated ultrasonographically before thyroid surgery. Thyroid nodules were categorised using the European Thyroid Imaging Reporting and Data System (EU-TIRADS PL), and cytopathology was assessed using Bethesda criteria. Neck ultrasound results and thyroid and autoimmune status were correlated with histopathological PTC assessment. Results: The coexistence of PTC and AIT was found in 48.9% (44/90) of patients. The percentage of AIT was increasing with age; AIT was present only in 1/3 of prepubertal, close to 50% in pubertal, and over 60% in adolescent patients. The youngest patients (aged <10 years old) presented more often with goitre and lymphadenopathy and less often with AIT than adolescents (15-18 years of age). There were no differences in TPOAb, TgAb, and TSH levels between the age subgroups. Presurgical TgAb levels were higher than those of TPOAb in the youngest patients. Histopathological analysis revealed that the solid subtype was observed more often in prepubertal children and diffuse sclerosing in children below 14 years of age, whereas the classic subtype dominated in late pubertal. Univariate and multivariate analyses revealed that lymph nodes metastases (LNM) were associated with PTC diameter and fT4 level, whereas extrathyroidal extension with age and angioinvasion with PTC diameter and age. The correlations between age and fibrosis, and the presence of psammoma bodies in malignant tissues were close to significant. We did not observe an association between TSH levels and the presence of autoimmunity and PTC variables. Conclusions: In paediatric patients the natural course of PTC may be less aggressive in adolescent patients than in younger children (especially < 10 years of age). We suggest that pre-operative evaluation of paediatric patients with thyroid nodules could include apart from assessment of thyroid hormones, evaluation of TPOAb, TgAb, and TRAb together with comprehensive neck ultrasonography.


Asunto(s)
Carcinoma Papilar , Enfermedad de Hashimoto , Neoplasias de la Tiroides , Nódulo Tiroideo , Tiroiditis Autoinmune , Femenino , Adolescente , Humanos , Niño , Masculino , Cáncer Papilar Tiroideo/diagnóstico , Cáncer Papilar Tiroideo/complicaciones , Estudios Retrospectivos , Nódulo Tiroideo/complicaciones , Estudios de Seguimiento , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/complicaciones , Carcinoma Papilar/diagnóstico por imagen , Carcinoma Papilar/complicaciones , Tiroiditis Autoinmune/complicaciones , Enfermedad de Hashimoto/complicaciones , Ultrasonografía/efectos adversos , Tirotropina
9.
Cancers (Basel) ; 13(1)2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33401726

RESUMEN

Markers of bladder cancer cells remain elusive, which is a major cause of the low recognition of this malignant neoplasm and its recurrence. This implies an urgent need for additional diagnostic tools which are based on the identification of the chemism of bladder cancer. In this study, we employed label-free techniques of molecular imaging-Fourier Transform Infrared and Raman spectroscopic imaging-to investigate bladder cancer cell lines of various invasiveness (T24a, T24p, HT-1376, and J82). The urothelial HCV-29 cell line was the healthy control. Specific biomolecules discriminated spatial distribution of the nucleus and cytoplasm and indicated the presence of lipid bodies and graininess in some cell lines. The most prominent discriminators are the total content of lipids and sugar moieties as well as the presence of glycogen and other carbohydrates, un/saturated lipids, cytochromes, and a level of S-S bridges in proteins. The combination of the obtained hyperspectral database and chemometric methods showed a clear differentiation of each cell line at the level of the nuclei and cytoplasm and pointed out spectral signals which differentiated bladder cancer cells. Registered spectral markers correlated with biochemical composition changes can be associated with pathogenesis and potentially used for the diagnosis of bladder cancer and response to experimental therapies.

10.
Cancers (Basel) ; 13(22)2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34830887

RESUMEN

Bladder urothelial carcinoma (BC) is a common, recurrent, life-threatening, and unpredictable disease which is difficult to diagnose. These features make it one of the costliest malignancies. Although many possible diagnostic methods are available, molecular heterogeneity and difficulties in cytological or histological examination induce an urgent need to improve diagnostic techniques. Herein, we applied Fourier transform infrared spectroscopy in imaging mode (FTIR) to investigate patients' cytology samples assigned to normal (N), low-grade (LG) and high-grade (HG) BC. With unsupervised hierarchical cluster analysis (UHCA) and hematoxylin-eosin (HE) staining, we observed a correlation between N cell types and morphology. High-glycogen superficial (umbrella) and low-glycogen piriform urothelial cells, both with normal morphology, were observed. Based on the spectra derived from UHCA, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were performed, indicating a variation of protein content between the patient groups. Moreover, BC spectral cytology identified a low number of high-glycogen cells for which a shift of the carbohydrate/phosphate bands was also observed. Despite high cellular heterogeneity, PLS-DA was able to classify the spectra obtained. The voided urine FTIR cytology is one of the options that might be helpful in BC diagnosis, as high sensitivity and specificity up to 97% were determined.

11.
Cancers (Basel) ; 13(2)2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33418894

RESUMEN

The current understanding of mechanisms underlying the formation of metastatic tumors has required multi-parametric methods. The tissue micro-environment in secondary organs is not easily evaluated due to complex interpretation with existing tools. Here, we demonstrate the detection of structural modifications in proteins using emerging Fourier Transform Infrared (FTIR) imaging combined with light polarization. We investigated lungs affected by breast cancer metastasis in the orthotopic murine model from the pre-metastatic phase, through early micro-metastasis, up to an advanced phase, in which solid tumors are developed in lung parenchyma. The two IR-light polarization techniques revealed, for the first time, the orientational ordering of proteins upon the progression of pulmonary metastasis of breast cancer. Their distribution was complemented by detailed histological examination. Polarized contrast imaging recognised tissue structures of lungs and showed deformations in protein scaffolds induced by inflammatory infiltration, fibrosis, and tumor growth. This effect was recognised by not only changes in absorbance of the spectral bands but also by the band shifts and the appearance of new signals. Therefore, we proposed this approach as a useful tool for evaluation of progressive and irreversible molecular changes that occur sequentially in the metastatic process.

12.
Eur J Pharm Biopharm ; 91: 111-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25681746

RESUMEN

Two cationic derivatives of γ-cyclodextrin (GCD) were synthesized by functionalization with glycidyltrimethylammonium chloride (GTMAC) and ethylenediamine (EDA). Both these derivatives (GCD-GTMAC and GCD-EDA) have been shown to interact strongly with anionic biopolymers, unfractionated heparin (UFH) and mucin, the latter showing their mucoadhesive properties. They form inclusion complexes with daidzein (DAI), an isoflavone displaying a multitude of physiological effects, much more efficiently than the unmodified GCD. It was also shown that the complexes of these GCD derivatives with DAI and Nile Red penetrate human fibroblasts and murine hippocampal neuronal cells indicating that cationic GCD derivatives can be considered as potential delivery systems for isoflavones and other poorly water soluble compounds. Moreover, it was found that DAI delivered in cationic GCD complexes decreased the level of the cellular glycosaminoglycans (GAGs) in normal fibroblasts suggesting their possible application in the control of GAGs in mucopolysaccharidoses, lysosomal storage diseases caused by pathological accumulation of GAGs in the cells.


Asunto(s)
Sistemas de Liberación de Medicamentos , Glicosaminoglicanos/antagonistas & inhibidores , Hipocampo/metabolismo , Isoflavonas/metabolismo , Neuronas/metabolismo , Fitoestrógenos/metabolismo , gamma-Ciclodextrinas/química , Absorción Fisiológica , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Sistemas de Liberación de Medicamentos/efectos adversos , Compuestos Epoxi/química , Etilenodiaminas/química , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Glicosaminoglicanos/metabolismo , Hipocampo/citología , Hipocampo/efectos de los fármacos , Humanos , Indicadores y Reactivos/química , Isoflavonas/administración & dosificación , Isoflavonas/farmacología , Isoflavonas/uso terapéutico , Enfermedades por Almacenamiento Lisosomal/tratamiento farmacológico , Enfermedades por Almacenamiento Lisosomal/metabolismo , Ratones , Mucopolisacaridosis/tratamiento farmacológico , Mucopolisacaridosis/metabolismo , Neuronas/citología , Neuronas/efectos de los fármacos , Fitoestrógenos/administración & dosificación , Fitoestrógenos/farmacología , Fitoestrógenos/uso terapéutico , Compuestos de Amonio Cuaternario/química , Solubilidad , gamma-Ciclodextrinas/efectos adversos
13.
PLoS One ; 10(3): e0119486, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25781030

RESUMEN

Protamine, the only registered antidote of unfractionated heparin (UFH), may produce a number of adverse effects, such as anaphylactic shock or serious hypotension. We aimed to develop an alternative UFH antidote as efficient as protamine, but safer and easier to produce. As a starting material, we have chosen generally non-toxic, biocompatible, widely available, inexpensive, and easy to functionalize polysaccharides. Our approach was to synthesize, purify and characterize cationic derivatives of dextran, hydroxypropylcellulose, pullulan and γ-cyclodextrin, then to screen them for potential heparin-reversal activity using an in vitro assay and finally examine efficacy and safety of the most active polymers in Wistar rat and BALB/c mouse models of experimentally induced arterial and venous thrombosis. Efficacy studies included the measurement of thrombus formation, activated partial thromboplastin time, bleeding time, and anti-factor Xa activity; safety studies included the measurement of hemodynamic, hematologic and immunologic parameters. Linear, high molecular weight dextran substituted with glycidyltrimethylammonium chloride groups at a ratio of 0.65 per glucose unit (Dex40-GTMAC3) is the most potent and the safest UFH inhibitor showing activity comparable to that of protamine while possessing lower immunogenicity. Cationic polysaccharides of various structures neutralize UFH. Dex40-GTMAC3 is a promising and potentially better UFH antidote than protamine.


Asunto(s)
Antídotos/farmacología , Cationes/química , Antagonistas de Heparina/farmacología , Heparina/química , Polímeros/farmacología , Trombosis/tratamiento farmacológico , Trombosis/inmunología , Animales , Presión Sanguínea/efectos de los fármacos , Femenino , Heparina/metabolismo , Inmunización , Masculino , Ratones , Ratones Endogámicos BALB C , Tiempo de Tromboplastina Parcial , Polímeros/química , Polisacáridos/química , Protaminas/metabolismo , Ratas , Ratas Wistar , Trombosis/metabolismo
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