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1.
Eur Radiol ; 33(10): 7178-7185, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37142867

RESUMO

PURPOSE: To study the association between ultrasound cortical thickness in reactive post-vaccination lymph nodes and the elicited humoral response and to evaluate the performance of cortical thickness as a predictor of vaccine effectiveness in patients with and without a previous history of COVID-19 infection. METHODS: A total of 156 healthy volunteers were recruited and followed prospectively after receiving two COVID-19 vaccination doses using different protocols. Within a week after receiving the second dose, an axillary ultrasound of the ipsilateral vaccinated arm was performed, and serial post-vaccination serologic tests (PVST) were collected. Maximum cortical thickness was chosen as a nodal feature to analyze association with humoral immunity. Total antibodies quantified during consecutive PVST in previously-infected patients and in coronavirus-naïve volunteers were compared (Mann-Whitney U test). The association between hyperplastic-reactive lymph nodes and effective humoral response was studied (odds ratio). The performance of cortical thickness in detecting vaccination effectiveness was evaluated (area under the ROC curve). RESULTS: Significantly higher values for total antibodies were observed in volunteers with a previous history of COVID-19 infection (p < 0.001). The odds ratio associating immunized coronavirus-naïve volunteers after 90 and 180 days of the second dose with a cortical thickness ≥ 3 mm was statistically significant (95% CI 1.52-6.97 and 95% CI 1.47-7.29, respectively). The best AUC result was obtained comparing antibody secretion of coronavirus-naïve volunteers at 180 days (0.738). CONCLUSIONS: Ultrasound cortical thickness of reactive lymph nodes in coronavirus-naïve patients may reflect antibody production and a long-term effective humoral response elicited by vaccination. CLINICAL RELEVANCE STATEMENT: In coronavirus-naïve patients, ultrasound cortical thickness of post-vaccination reactive lymphadenopathy shows a positive association with protective antibody titers against SARS-CoV-2, especially in the long term, providing new insights into previous publications. KEY POINTS: • Hyperplastic lymphadenopathy was frequently observed after COVID-19 vaccination. • Ultrasound cortical thickness of reactive post-vaccine lymph nodes may reflect a long-term effective humoral response in coronavirus-naïve patients.


Assuntos
COVID-19 , Linfadenopatia , Humanos , Vacinas contra COVID-19 , Voluntários Saudáveis , COVID-19/prevenção & controle , SARS-CoV-2 , Linfadenopatia/diagnóstico por imagem , Vacinação
2.
Eur Radiol ; 32(5): 3199-3206, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34655312

RESUMO

OBJECTIVES: This study was conducted in order to investigate COVID-19 vaccine influence on unilateral axillary lymph nodes, comparing nodal basal features with their characteristics after the first and second vaccination dose. METHODS: Ninety-one volunteer employees from our center who participated in the BNT162b2 (Pfizer-BioNTech) vaccination campaign were prospectively recruited. A total of three axillary ultrasound evaluations of the ipsilateral vaccinated arm were performed: before vaccination, the week after the first dose and the week after the second dose. The following findings were recorded: the total number of visible nodes, the maximum measurements of the diameter and cortex, Bedi's classification, and color Doppler evaluation. The collected data were compared using paired-sample Student's t-test for quantitative continuous variables and Wilcoxon rank-sum test for ordinal variables. Additional analyses were performed after classifying patients according to the previous history of COVID-19 disease. Differences among both groups were evaluated with the Mann-Whitney U test. Variables with a p value < 0.05 were considered statistically significant. RESULTS: Comparative analyses between the three US examinations showed a statistically significant augmentation of total visible nodes, maximum diameter, cortical thickness, grade of Bedi's classification, and Doppler signal (p < 0.001). Analyses between patients with and without previous COVID-19 infection showed a higher lymph node response in naïve patients compared to those who were previously infected. CONCLUSIONS: According to our results, both doses of COVID-19 vaccine induced an increase of all axillary lymph node parameters with statistically significant differences, especially in coronavirus-naïve patients. KEY POINTS: • Pfizer COVID-19 vaccine induces a high incidence of ipsilateral axillary lymphadenopathy. • US scan identified an increase of all lymph nodes parameters, especially in coronavirus-naïve patients.


Assuntos
COVID-19 , Linfadenopatia , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Seguimentos , Humanos , Linfadenopatia/diagnóstico por imagem , Linfadenopatia/etiologia , SARS-CoV-2
3.
Eur Radiol ; 32(10): 6598-6607, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35554651

RESUMO

OBJECTIVES: To assess ultrasound characteristics of ipsilateral axillary lymph nodes after two doses of four different COVID-19 vaccination protocols, to determine whether these parameters differed with age, and to describe how they changed on follow-up imaging. METHODS: A total of 247 volunteer employees from our center who had received two doses of COVID-19 vaccination were recruited and followed prospectively. Axillary ultrasound of the ipsilateral vaccinated arm was performed the week after receiving the second dose to analyze lymph node features (number, long-axis, cortical thickness, morphology, and vascular imaging). Axillary lymphadenopathy resulting from four vaccination protocols-mRNA (BNT162b2, mRNA-1273), ChAdOx1-S, and mix-and-match-was compared. Analysis was conducted using the Kruskal-Wallis test and post hoc analysis with Bonferroni corrections. Nodal reactogenicity was evaluated for two age groups: young (< 45 years old) and middle-aged ( ≥ 45 years old). All parameters were compared between both groups using an unpaired-sample Student t test. A p value < 0.05 was considered statistically significant. RESULTS: Significantly higher values for total number of visible nodes, cortical thickness, Bedi's classification (p < 0.001), and vascularity (p < 0.05) were observed in mRNA vaccine recipients compared to full ChAdOx1-S protocol recipients. Moreover, mix-and-match protocol recipients showed greater nodal cortical thickness and higher Bedi's classification than full ChAdOx1-S recipients (p < 0.001). Analyses between age groups revealed greater cortical thickness, Bedi's classification, and color Doppler signal in younger patients (p < 0.05). CONCLUSIONS: Nodal parameters of Bedi's classification and cortical thickness were more often increased in mRNA and mix-and-match vaccine recipients when compared to ChAdOx1-S vaccine alone, especially in younger patients. KEY POINTS: • Hyperplastic lymphadenopathy was observed more frequently in mRNA and mix-and-match vaccine protocols compared to full vector-based vaccination. • Higher values for cortical thickness, Bedi's classification, and color Doppler signal parameters were identified in younger patients. • Observed lymph node findings normalized in greater than 80% of patients by the third month following vaccination.


Assuntos
COVID-19 , Linfadenopatia , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Linfonodos/diagnóstico por imagem , Linfadenopatia/diagnóstico por imagem , Pessoa de Meia-Idade , RNA Mensageiro , Tomografia Computadorizada por Raios X , Vacinas Sintéticas , Vacinas de mRNA
4.
World J Urol ; 39(7): 2447-2452, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33079251

RESUMO

PURPOSE: The goal of the current study was to evaluate the effect of a standardized prostate mpMRI reporting template on urologists' understanding and confidence in counselling a patient on the results of the MRI. To do this we performed a survey study to assess the understanding and confidence of urologists reviewing reports prior to (pre) and after (post) adoption of a standardized mpMRI template. METHODS: Six urologists reviewed ten pre- and post- mpMRI templated reports and completed a survey to assess the clarity of key elements and the confidence in counseling the patient. The urologists were blinded to the study objective. Nonparametric constrained permutation test for significance was performed to compare the results prior to and after implementation of the template. RESULTS: 29 pre- and 30 post-template mpMRI reports were reviewed. The average score for the post-template reports was significantly higher (10.7 ± 0.6 vs 7.5 ± 2.7 [ p< 0.001]) regardless of the reviewer. Urologists were also overall more confident in counselling patients when the standardized mpMRI reporting template had been used. CONCLUSION: Implementation of a standardized template for reporting of prostate mpMRI findings resulted in improved clarity and confidence in counselling patients. Radiologists should consider implementing a standardized reporting template to improve clinicians' understanding and confidence of the report.


Assuntos
Formulários como Assunto , Imageamento por Ressonância Magnética Multiparamétrica , Próstata/diagnóstico por imagem , Projetos de Pesquisa/normas , Humanos , Masculino , Melhoria de Qualidade
5.
Nanotechnology ; 31(19): 195707, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31995521

RESUMO

Polycyclic hydrocarbons constitute an important source of very dangerous pollutants. Different materials have been used as adsorbent for their removal, but they present difficulties in the separation process. The use of a material based on metal-organic framework (MOF) with large pores and high surface area and magnetic nanoparticles with superparamagnetic properties is an interesting strategy. In this work a magnetic composite based on MOF (MIL-101) and Fe3O4 magnetic nanoparticles (Fe3O4/MIL-101) was obtained by a simple synthesis method and used as adsorbent for the removal of anthracene. The composite was characterized by transmission electron microscopy, x-ray powder diffraction and vibrating sample magnetometer. The results showed that kinetic data followed a first-order model and equilibrium data were well fitted by the Langmuir model. The maximum adsorption capacity was 12.7 mg g-1 at pH 6 in 60 min of exposure. The composite was applied for the adsorption of anthracene in water samples reaching more than 95% of anthracene removal in 1 h of contact. The composite material was effectively separated using an external magnet, and no further centrifugation or filtration processes were needed. This composite is a great alternative to remove polycyclic hydrocarbons from water samples and has potential to extend to the removal of other contaminants.

6.
Acta Radiol ; 61(10): 1335-1342, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31979977

RESUMO

BACKGROUND: Recently, a new mammography system to perform contrast-enhanced mammography has become available in the market. For the high-energy acquisition, it uses a titanium filter instead of a copper one, reducing the tube load while maintaining image quality. PURPOSE: To retrospectively evaluate the accuracy of contrast-enhanced mammography with a titanium filter (TiCEM) in three readers with different grades of experience. MATERIAL AND METHODS: IRB-approved retrospective multicentric lesion by lesion study with 200 lesions, all of them initially classified as BI-RADS categories 0/3/4/5 on mammography and/or ultrasound and with pathological confirmation, in 135 patients. Three readers with different levels of experience (expert, resident, intermediate) blinded to the final diagnosis, retrospectively evaluated the low-energy (LE) images and the combination of LE and recombined (subtracted) images and classified the lesions according to the BI-RADS categories. Reader 1 also categorized the breast density. ROC curves were performed for each reader. RESULTS: Out of the 200 lesions, 82 were benign and 118 malignant (20 DCIS, 10 ILC, 88 IDC). The AUCs of LE versus TiCEM for were: Reader 1: 0.7 vs. 0.88, P < 0.001; Reader 2: 0.63 vs. 0.83, P < 0.001; and Reader 3: 0.63 vs. 0.84, P < 0.001. For the three readers, the AUCs of LE versus TiCEM were significantly superior in both dense and non-dense breasts (P < 0.001). Comparing the AUC of LE for Reader 1 (expert) versus the AUC of TiCEM for Reader 2 (resident) there were significant differences (0.7 vs. 0.83, P < 0.001). CONCLUSION: The accuracy of TiCEM was significantly better for all the readers, in both dense and non-dense breasts. The accuracy of a resident reading a TiCEM study was better than the accuracy of an expert radiologist reading LE images.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/instrumentação , Titânio/química , Idoso , Neoplasias da Mama/patologia , Meios de Contraste , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Sensors (Basel) ; 19(20)2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31635083

RESUMO

In this paper, we report the synthesis, characterization, and application of a new fluorescent nanosensor based on water-soluble CdTe quantum dots (QDs) coated with cysteamine (CA) for the determination of folic acid (FA). CdTe/CA QDs were characterized by high-resolution transmission electron microscopy, the zeta potential, and Fourier-transform infrared (FT-IR), UV-visible, and fluorescence spectroscopy. CdTe QDs coated with mercaptopropionic acid (MPA) and glutathione (GSH) were prepared for comparison purposes. The effect of FA on the photoluminescence intensity of the three thiol-capped QDs at pH 8 was studied. Only CdTe/CA QDs showed a notable fluorescence quenching in the presence of FA. Then, a nanosensor based on the fluorescence quenching of the CdTe QDs at pH 8 was explored. Under optimum conditions, the calibration curve showed a linear fluorescence quenching response in a concentration range of FA from 0.16 to 16.4 µM (R2 = 0.9944), with a detection limit of 0.048 µM. A probable mechanism of fluorescence quenching was proposed. The nanosensor showed good selectivity over other possible interferences. This method has been applied for FA quantification in orange beverage samples with excellent results (recoveries from 98.3 to 103.9%). The good selectivity, sensitivity, low cost, and rapidity make CdTe /CA QDs a suitable nanosensor for FA determination.

8.
Acta Radiol ; 59(6): 649-656, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28870087

RESUMO

Background In 2014, Siemens developed a new software-based scatter correction (Progressive Reconstruction Intelligently Minimizing Exposure [PRIME]), enabling grid-less digital mammography. Purpose To compare doses and image quality between PRIME (grid-less) and standard (with anti-scatter grid) modes. Material and Methods Contrast-to-noise ratio (CNR) was measured for various polymethylmethacrylate (PMMA) thicknesses and dose values provided by the mammograph were recorded. CDMAM phantom images were acquired for various PMMA thicknesses and inverse Image Quality Figure (IQFinv) was calculated. Values of incident entrance surface air kerma (ESAK) and average glandular dose (AGD) were obtained from the DICOM header for a total of 1088 pairs of clinical cases. Two experienced radiologists compared subjectively the image quality of a total of 149 pairs of clinical cases. Results CNR values were higher and doses were lower in PRIME mode for all thicknesses. IQFinv values in PRIME mode were lower for all thicknesses except for 40 mm of PMMA equivalent, in which IQFinv was slightly greater in PRIME mode. A mean reduction of 10% in ESAK and 12% in AGD in PRIME mode with respect to standard mode was obtained. The clinical image quality in PRIME and standard acquisitions resulted to be similar in most of the cases (84% for the first radiologist and 67% for the second one). Conclusion The use of PRIME software reduces, in average, the dose of radiation to the breast without affecting image quality. This reduction is greater for thinner and denser breasts.


Assuntos
Mama/diagnóstico por imagem , Mamografia/métodos , Intensificação de Imagem Radiográfica , Software , Densidade da Mama , Feminino , Humanos , Imagens de Fantasmas , Doses de Radiação , Estudos Retrospectivos
9.
Eur Radiol ; 27(8): 3190-3198, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28004161

RESUMO

OBJECTIVE: Our aim was to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) fused with prone 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in primary tumour staging of patients with breast cancer. METHODS: This retrospective study evaluated 45 women with 49 pathologically proven breast carcinomas. MRI and prone PET-CT scans with time-of-flight and point-spread-function reconstruction were performed with the same dedicated breast coil. The studies were assessed by a radiologist and a nuclear medicine physician, and evaluation of fused images was made by consensus. The final diagnosis was based on pathology (90 lesions) or follow-up ≥ 24 months (17 lesions). RESULTS: The study assessed 72 malignant and 35 benign lesions with a median size of 1.8 cm (range 0.3-8.4 cm): 31 focal, nine multifocal and nine multicentric cases. In lesion-by-lesion analysis, sensitivity, specificity, positive and negative predictive values were 97%, 80%, 91% and 93% for MRI, 96%, 71%, 87%, and 89% for prone PET, and 97%. 94%, 97% and 94% for MRI fused with PET. Areas under the curve (AUC) were 0.953, 0.850, and 0.983, respectively (p < 0.01). CONCLUSIONS: MRI fused with FDG-PET is more accurate than FDG-PET in primary tumour staging of breast cancer patients and increases the specificity of MRI. KEY POINTS: • FDG PET-CT may improve the specificity of MRI in breast cancer staging. • MRI fused with prone 2-[fluorine-18]-fluoro-2-deoxy-D-glucose PET-CT has better overall diagnostic performance than MRI. • The clinical role of fused PET-MRI has not yet been established.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18/administração & dosagem , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Tomografia por Emissão de Pósitrons/métodos , Valor Preditivo dos Testes , Decúbito Ventral , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
10.
Acta Radiol ; 58(6): 645-651, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28273729

RESUMO

Background Digital breast tomosynthesis (DBT) and ultrasound (US) can detect additional cancers after negative mammography. However, not all cancers are visible by both techniques. Purpose To study the role of the amount of peritumoral fat in the detection of additional cancers with DBT or US. Material and Methods One reader retrospectively reviewed 142 breast cancers in 109 women who underwent mammography, DBT, US, and magnetic resonance imaging (MRI). Two readers in consensus evaluated the additional cancers detected by US, DBT, or MRI, and classified them into four groups according to the amount of peritumoral adipose tissue: group I, >75% of peritumoral fat; group II, 50-74%; group III, 25-49%, and group IV, 0-24%. The detection of additional cancers by US and DBT with respect to the other imaging techniques was evaluated. Results Seventy-eight cancers were detected by mammography and the remaining 64 cancers were detected by DBT, US, or MRI. US and DBT detected 46 (71.8%) and 25 (39.06%) additional tumors, respectively. Statistical significance was only found in group IV ( P < 0.01). Conclusion US detected more tumors than DBT in lesions surrounded by a small amount of fat. No significant differences were found between US and DBT in the detection of additional cancers in the other groups.


Assuntos
Tecido Adiposo/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Mamografia , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias Primárias Múltiplas/patologia , Ultrassonografia Mamária , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Acta Radiol ; 57(1): 13-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25523063

RESUMO

BACKGROUND: Digital mammography (DM) is widespread used for the detection of breast cancer, but its sensitivity drops in dense breasts. It is well known that additional breast ultrasound (US) and digital breast tomosynthesis (DBT) increase the sensitivity of DM. However, to our knowledge, there are no articles comparing the role of both additional techniques. PURPOSE: To assess the diagnostic performance of DM and the different combinations of DM + additional DBT and DM + additional US in an enriched sample of patients. MATERIAL AND METHODS: Retrospective study in an enriched sample of 1042 patients. Out of them, 84 patients had histologically proven malignant lesions and 258 patients had benign lesions. Finally 700 patients with normal explorations or benign lesions without biopsy confirmation (but stable for at least 12 months) were included. All of them underwent DM, US, and DBT examinations that were retrospectively reviewed by one expert radiologist, blinded to the final diagnoses. The DBT examinations were performed using one single view with wide angle (50°). The reader categorized the cases as benign (BI-RADS 1 or 2) or malignant (BI-RADS 3-5) for DM and the different combination of techniques. The sensitivity (SE) and specificity (SP) were calculated with the PEPI software and the ROC curves of the different techniques and combinations were calculated by using the SPSS 15.0 software. RESULTS: The SE and SP of DM were 69.05% and 88.20%, respectively. Additional DBT significantly increased the AUC of DM as well as additional US or the combination DM + DBT + US (P < 0.05). However there were no significant differences between the AUC of DM + US and DM + DBT (P = 0.7). CONCLUSION: Additional US, DBT, or both, in combination with DM, significantly increased the AUC of DM. However, there were no significant differences between DM + DBT and DM + US.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador , Ultrassonografia Mamária/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Eur Radiol ; 25(12): 3669-78, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26002130

RESUMO

UNLABELLED: This paper summarizes information about breast MRI to be provided to women and referring physicians. After listing contraindications, procedure details are described, stressing the need for correct scheduling and not moving during the examination. The structured report including BI-RADS® categories and further actions after a breast MRI examination are discussed. Breast MRI is a very sensitive modality, significantly improving screening in high-risk women. It also has a role in clinical diagnosis, problem solving, and staging, impacting on patient management. However, it is not a perfect test, and occasionally breast cancers can be missed. Therefore, clinical and other imaging findings (from mammography/ultrasound) should also be considered. Conversely, MRI may detect lesions not visible on other imaging modalities turning out to be benign (false positives). These risks should be discussed with women before a breast MRI is requested/performed. Because breast MRI drawbacks depend upon the indication for the examination, basic information for the most important breast MRI indications is presented. Seventeen notes and five frequently asked questions formulated for use as direct communication to women are provided. The text was reviewed by Europa Donna-The European Breast Cancer Coalition to ensure that it can be easily understood by women undergoing MRI. KEY POINTS: • Information on breast MRI concerns advantages/disadvantages and preparation to the examination • Claustrophobia, implantable devices, allergic predisposition, and renal function should be checked • Before menopause, scheduling on day 7-14 of the cycle is preferred • During the examination, it is highly important that the patient keeps still • Availability of prior examinations improves accuracy of breast MRI interpretation.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/patologia , Imageamento por Ressonância Magnética/métodos , Guias de Prática Clínica como Assunto , Europa (Continente) , Feminino , Humanos
13.
Br J Clin Pharmacol ; 85(8): 1670-1683, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30933365

RESUMO

AIMS: Immunotherapy is a rising alternative to traditional treatment in breast cancer (BC) patients in order to transform cold into hot immune enriched tumours and improve responses and outcome. A computational modelling approach was applied to quantify modulation effects of immunotherapy and chemotherapy response on tumour shrinkage and progression-free survival (PFS) in naïve BC patients. METHODS: Eighty-three Her2-negative BC patients were recruited for neoadjuvant chemotherapy with or without immunotherapy based on dendritic cell vaccination. Sequential tumour size measurements were modelled using nonlinear mixed effects modelling and linked to PFS. Data from another set of patients (n = 111) were used to validate the model. RESULTS: Tumour size profiles over time were linked to biomarker dynamics and PFS. The immunotherapy effect was related to tumour shrinkage (P < .05), with the shrinkage 17% (95% confidence interval: 2-23%) being higher in vaccinated patients, confirmed by the finding that pathological complete response rates in the breast were higher in the vaccinated compared to the control group (25.6% vs 13.6%; P = .04). The whole tumour shrinkage time profile was the major prognostic factor associated to PFS (P < .05), and therefore, immunotherapy influences indirectly on PFS, showing a trend in decreasing the probability of progression with increased vaccine effects. Tumour subtype was also associated with PFS (P < .05), showing that luminal A BC patients have better prognosis. CONCLUSIONS: Dendritic cell-based immunotherapy is effective in decreasing tumour size. The semi-mechanistic validated model presented allows the quantification of the immunotherapy treatment effects on tumour shrinkage and establishes the relationship between the dynamics of tumour size and PFS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Vacinas Anticâncer/administração & dosagem , Células Dendríticas/imunologia , Modelos Biológicos , Terapia Neoadjuvante/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/imunologia , Mama/patologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Vacinas Anticâncer/imunologia , Estudos de Casos e Controles , Quimioterapia Adjuvante , Estudos de Coortes , Simulação por Computador , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Carga Tumoral/imunologia
14.
ScientificWorldJournal ; 2014: 725981, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24511299

RESUMO

A regioselective synthesis has been developed for the preparation of a series of N,N'-disubstituted 4,4'-carbonylbis(carbamoylbenzoic) acids and N,N'-disubstituted bis(carbamoyl) terephthalic acids by treatment of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (1) and 1,2,4,5-benzenetetracarboxylic dianhydride (2) with arylalkyl primary amines (A-N). The carbamoylcarboxylic acid derivatives were synthesized with good yield and high purity. The specific reaction conditions were established to obtain carbamoyl and carboxylic acid functionalities over the thermodynamically most favored imide group. Products derived from both anhydrides 1 and 2 were isolated as pure regioisomeric compounds under innovative experimental conditions. The chemo- and regioselectivity of products derived from dianhydrides were determined by NMR spectroscopy and confirmed by density functional theory (DFT). All products were characterized by NMR, FTIR, and MS.


Assuntos
Anidridos/química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/síntese química , Técnicas de Química Sintética , Modelos Moleculares , Conformação Molecular
15.
Surg Obes Relat Dis ; 20(5): 462-466, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38155076

RESUMO

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) is the most common Bariatric procedure in the United States; however, the frequency of conversion to Roux-en-Y gastric bypass (RYGB) is unknown. OBJECTIVES: The primary aim was to determine the conversion rate over time from LSG to RYGB. The secondary objectives were to evaluate factors associated with conversion and postconversion weight loss outcomes. SETTING: Single Academic Institution, Center of Bariatric Excellence. METHODS: A retrospective analysis of all LSG from 2011 to 2020 was done. Kaplan-Meier analysis was utilized to estimate the conversion rate over time after LSG. Cox regression was utilized to identify predictors of future conversion. RESULTS: Of 875 LSGs, 46 were converted to RYGB from 2011 to 2020. Median follow-up was 2.6 years, and 7-year follow-up rate was 59.9%. The 1-year conversion rate was 1.4%, increasing to 3.8%, 9.0%, and 12.6% at 3, 5, and 7 years respectively. Female gender (hazard ratio [HR] = 4.2, P = .05) and age <55 (HR = 3.5, P = .04) were associated with greater chance of conversion. Preoperative asthma (HR = 1.7, P = .14) and gastroesophageal reflux disease (GERD) (HR = 1.5, P = .18) trended toward higher conversion but were not significant. Of those with body mass index (BMI) >35 at time of conversion, the mean total body weight loss (TBWL) was 13.0% at the time of conversion. This subgroup had additional 13.6% of TBWL 1-year after conversion. CONCLUSIONS: Conversion of LSG to RYGB increased with time to 12.6% conversion rate at 7-years. Patients with GERD prior to LSG had a nonsignificant trend toward conversion, while younger patients and females had significantly higher rates of conversion. There may be additional weight loss benefit for patients converted to RYGB.


Assuntos
Gastrectomia , Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Redução de Peso , Humanos , Feminino , Masculino , Estudos Retrospectivos , Redução de Peso/fisiologia , Derivação Gástrica/métodos , Derivação Gástrica/estatística & dados numéricos , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Gastrectomia/métodos , Gastrectomia/estatística & dados numéricos , Adulto , Resultado do Tratamento
16.
PLoS One ; 19(9): e0310009, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39240987

RESUMO

Traditional pastures in temperate regions face limitations such as reduced growth and nutritional quality during the summer season. Plantain (P. lanceolata L.) offers advantages like increased yield and decreased nitrogen losses from grazing ruminants. Effective grazing management is essential for pasture health, and defoliation frequency and intensity play a pivotal role. This study aimed to evaluate plantain's regrowth, yield, and morpho-physiological and chemical responses under different defoliation frequencies and intensities, with the goal of enhancing its management in pastures. The study was conducted in pots within a controlled-environment growth chamber, examining the impact of three defoliation frequencies (based on extended leaf length: 15, 25 and 35 cm) and two defoliation intensities (5 and 8 cm of residual heights) with four replicates (24 pots as experimental units). The variables of interest were morphological characteristics, dry matter (DM) accumulation, herbage chemical composition, growth rate traits, and photosynthetic parameters. Defoliation frequency affected plantain's growth and nutritional composition. More frequent cuts (15 cm) resulted in lower DM yield per cut and lower stem content, while less frequent cuts (35 cm) produced higher values. Defoliation intensity influenced the proportion of leaves and stems in the total DM, with 5 cm cuts favoring leaves. Nutrient content was also affected by defoliation frequency, with less frequent cuts (35 cm) showing lower crude protein concentration and metabolizable energy content but higher neutral detergent fiber and water-soluble carbohydrate concentration. Plantain's growth rate variables were mainly influenced by defoliation frequency, with less frequent cuts promoting faster leaf appearance and growth of new leaves. The basal fluorescence variables and chlorophyll content were affected by cutting frequency, being highest when cut less frequently (35 cm), while no differences were found in the actual quantum efficiency among different defoliation frequencies and intensities. The fraction of light dedicated to non-photochemical quenching was highest when cut less frequently and more intensively. Overall, defoliation at 25 cm of extended leaf length balanced plantain forage quality and regrowth capacity.


Assuntos
Folhas de Planta , Plantago , Plantago/crescimento & desenvolvimento , Plantago/fisiologia , Plantago/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Fotossíntese , Estações do Ano
17.
Surg Obes Relat Dis ; 19(6): 626-631, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36646542

RESUMO

BACKGROUND: Gastrogastric fistula (GGF) is a rare complication from Roux-en-Y gastric bypass (RYGB). It is a known risk factor associated with weight recidivism and an indication for Bariatric Revisional Surgery (BRS). OBJECTIVES: The primary outcome of this study is to evaluate perioperative outcomes and the long-term total body weight loss (TBWL) outcomes following revision. SETTING: Single Academic Institution, Center of Bariatric Excellence. METHODS: We selected patients who had primary bariatric surgery and BRS from 2003 to 2020, followed by BRS for GGF. Patients' demographics, perioperative outcomes, and TBWL were analyzed. RESULTS: One hundred five patients underwent BRS for GGF. Mean body mass index (BMI) at index operation and revision was 51.6 ± 10.1, and 42.4 ± 11.2 respectively. Ninety percent of patients had open primary RYGB, and 69% had open revisional surgery. The median length of stay after BRS was 3 days. The 30-day reintervention rate was 19%. The 30-day readmission rate was 34%. Of the 77 patients included for weight loss analysis, the mean %TBWL after primary RYGB was 34% ± 14. The total mean %TBWL at the time of revision was 18.8%, translating into a weight regain of 13.6% ± 9.5. The total mean %TBWL after revision was 37.6% ± 11.4, translating into TBWL of 18.8% ± 9.4 after revision when compared to TBWL at revision time. CONCLUSIONS: Our results demonstrate that revision for GGF can be safely performed, however is associated with higher morbidity than primary bariatric surgery. Revision for GGF results in significant long-term weight loss.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Fístula Gástrica , Laparoscopia , Obesidade Mórbida , Humanos , Derivação Gástrica/efeitos adversos , Derivação Gástrica/métodos , Obesidade Mórbida/cirurgia , Obesidade Mórbida/complicações , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Cirurgia Bariátrica/efeitos adversos , Fístula Gástrica/etiologia , Fístula Gástrica/cirurgia , Redução de Peso , Reoperação/métodos , Estudos Retrospectivos , Resultado do Tratamento
18.
Am Surg ; 89(12): 5801-5805, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37167426

RESUMO

INTRODUCTION: The rate of marginal ulcer (MU) following primary Roux-en-Y Gastric Bypass (RYGB) is approximately .6-16%. Few studies have evaluated recurrence rates following surgical revision for MU. The primary aim of this study was to determine the rate of MU recurrence following revision. The secondary aim was to evaluate the impact of truncal vagotomy (TV) on the recurrence rates and analyze potential risk factors associated with the recurrence of MU after revision. METHODS: We conducted a retrospective cohort study examining data at a single tertiary academic medical center. Adult patients with a history of RYGB who underwent gastrojejunostomy revision for recurrent MU between the years of 2003-2020 were included. We sought to determine our overall rate of MU following revision, with and without TV. Additionally, we examined the association of risk factors with MU recurrence. Fisher's exact test was used to determine the statistical significance of recurrence rates between the groups. RESULTS: We included 90 patients in the study. The overall recurrence rate for MU was 16.7%. Of the 90 patients, 35 (35.4%) patients underwent TV at the time of revision. The recurrence rate of MU after GJ revision with TV was 14.3% in comparison to those without TV, 18.2% (P = .775). Smoking, steroid, alcohol use, history of cardiac surgery/intervention, and helicobacter pylori were not significantly associated with recurrent MU following revision. CONCLUSIONS: The rate of recurrence after revision for MU is high. Adding TV trended towards decreased MU recurrence after revisional surgery, however not significant. Larger studies are needed to evaluate risk factors associated with recurrent MU after revision.


Assuntos
Derivação Gástrica , Úlcera Péptica , Adulto , Humanos , Derivação Gástrica/efeitos adversos , Estudos Retrospectivos , Úlcera Péptica/epidemiologia , Úlcera Péptica/cirurgia , Vagotomia Troncular , Reoperação/efeitos adversos
19.
Invest Clin ; 53(3): 289-300, 2012 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-23248972

RESUMO

Cardiac tumors are rare entities in clinical practice, with an incidence of 0.05%. Approximately 75% are benign and 25% malignant. Among these, Lymphomas are uncommon, representing about 0.25%. The non-Hodgkin lymphomas can occur in extranodal tissues in 20% of the cases and 80% of these non-Hodgkin lymphomas are composed of diffuse B cells. The extranodal presentation is most frequent in young adults, with a high degree of malignancy and rapid growth. It can present with primary infiltration of various organs; cardiac involvement occurs in 20 to 28% of cases, usually located in the right chambers and with nonspecific symptoms, depending on the location and extent of the tumor. The diagnostic test in these cases is undoubtedly the biopsy of the lymph node or the affected tissue. We present the case of non-Hodgkin disease of diffuse large cells, with right intra-atrial involvement in a 23-year-old-female patient, who presented with progressive dyspnea. A transesophageal echocardiography was performed and an intra-atrial tumor mass was detected. A biopsy was performed, by femoral venous catheterization, allowing the establishment of the histopathological diagnosis and treatment. At a one year follow up, the patient shows complete remission.


Assuntos
Átrios do Coração , Neoplasias Cardíacas/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Feminino , Humanos , Adulto Jovem
20.
Polymers (Basel) ; 14(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35808698

RESUMO

The manufacturing process in thermoset-based carbon fiber-reinforced polymers (CFRPs) usually requires a curing stage where the material is transformed from a gel state to a monolithic solid state. During the curing process, micro-residual stresses are developed in the material due to the different chemical-thermal-mechanical properties of the fiber and of the polymer, reducing the mechanical performance of the composite material compared to the nominal performance. In this study, computational micromechanics is used to analyze the micro-residual stresses development and to predict its influence on the mechanical performance of a pre-impregnated unidirectional CFRP made of T700-fibers and an aeronautical grade epoxy. The numerical model of a representative volume element (RVE) was developed in the commercial software Abaqus® and user-subroutines are used to simulate the thermo-curing process coupled with the mechanical constitutive model. Experimental characterization of the bulk resin properties and curing behavior was made to setup the models. The higher micro-residual stresses occur at the thinner fiber gaps, acting as triggers to failure propagation during mechanical loading. These micro-residual stresses achieve peak values above the yield stress of the resin 55 MPa, but without achieving damage. These micro-residual stresses reduce the transverse strength by at least 10%, while the elastic properties remain almost unaffected. The numerical results of the effective properties show a good agreement with the macro-scale experimentally measured properties at coupon level, including transverse tensile, longitudinal shear and transverse shear moduli and strengths, and minor in-plane and transverse Poisson's ratios. A sensitivity analysis was performed on the thermal expansion coefficient, chemical shrinkage, resin elastic modulus and cure temperature. All these parameters change the micro-residual stress levels and reduce the strength properties.

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