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1.
Medicina (Kaunas) ; 60(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39064518

RESUMO

Background and Objectives: Radiofrequency catheter ablation (RFCA) is a highly successful intervention. By comparing the lesion changes in prostate parenchymal and striated muscle tissues after RFCA with and without cooling, it was possible to assess the correlation between the shape regularity, area, and perimeter of the thermal lesion, and to predict the geometric shape changes of the lesions. Materials and Methods: A standard prostate and striated muscle RFCA procedure was performed on 13 non-purebred dogs in two sessions: no cooling and cooling with 0.1% NaCl solution. Microtome-cut 2-3 µm sections of tissue samples were stained with haematoxylin and eosin and further examined. The quotient formula was employed to evaluate the geometric shape of the damage zones at the ablation site. Results: The extent of injury following RFCA in striated muscle tissue was comparable to that in prostate parenchymal tissue. Regression analysis indicated a strong and positive relationship between area and perimeter in all experimental groups. In the experimental groups of parenchymal tissues with and without cooling, an increase in the area or perimeter of the damage zone corresponded to an increase in the quotient value. A similar tendency was observed in the striated muscle group with cooling. However, in the striated muscle group without cooling, an increase in lesion area or perimeter lowered the quotient value. Standardised regression coefficients demonstrated that in the striated muscle with cooling, the damage zone shape was more determined by area than perimeter. However, in the parenchymal tissue, the perimeter had a more substantial impact on the damage zone shape than the area. Conclusions: The damage area and perimeter have predictive power on the overall shape regularity of damage zone geometry in both striated muscles and parenchymal tissue. This approach is employed to achieve a balance between the need for tumour eradication and the minimisation of ablation-induced complications to healthy tissue.


Assuntos
Ablação por Cateter , Músculo Estriado , Animais , Masculino , Ablação por Cateter/métodos , Ablação por Cateter/efeitos adversos , Cães , Tecido Parenquimatoso , Próstata/cirurgia , Próstata/patologia , Músculo Esquelético/lesões
2.
Eur Radiol ; 33(9): 6204-6212, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37017702

RESUMO

OBJECTIVES: To investigate whether MRI-based measurements of fibro-glandular tissue volume, breast density (MRBD), and background parenchymal enhancement (BPE) could be used to stratify two cohorts of healthy women: BRCA carriers and women at population risk of breast cancer. METHODS: Pre-menopausal women aged 40-50 years old were scanned at 3 T, employing a standard breast protocol including a DCE-MRI (35 and 30 participants in high- and low-risk groups, respectively). The dynamic range of the DCE protocol was characterised and both breasts were masked and segmented with minimal user input to produce measurements of fibro-glandular tissue volume, MRBD, and voxelwise BPE. Statistical tests were performed to determine inter- and intra-user repeatability, evaluate the symmetry between metrics derived from left and right breasts, and investigate MRBD and BPE differences between the high- and low-risk cohorts. RESULTS: Intra- and inter-user reproducibility in estimates of fibro-glandular tissue volume, MRBD, and median BPE estimations were good, with coefficients of variation < 15%. Coefficients of variation between left and right breasts were also low (< 25%). There were no significant correlations between fibro-glandular tissue volume, MRBD, and BPE for either risk group. However, the high-risk group had higher BPE kurtosis, although linear regression analysis did not reveal significant associations between BPE kurtosis and breast cancer risk. CONCLUSIONS: This study found no significant differences or correlations in fibro-glandular tissue volume, MRBD, or BPE metrics between the two groups of women with different levels of breast cancer risk. However, the results support further investigation into the heterogeneity of parenchymal enhancement. KEY POINTS: • A semi-automated method enabled quantitative measurements of fibro-glandular tissue volume, breast density, and background parenchymal enhancement with minimal user intervention. • Background parenchymal enhancement was quantified over the entire parenchyma, segmented in pre-contrast images, thus avoiding region selection. • No significant differences and correlations in fibro-glandular tissue volume, breast density, and breast background parenchymal enhancement were found between two cohorts of women at high and low levels of breast cancer risk.


Assuntos
Neoplasias da Mama , Mama , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Densidade da Mama , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
3.
Am J Physiol Lung Cell Mol Physiol ; 322(6): L882-L889, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35537098

RESUMO

Lung resistance (RL) is determined by airway and parenchymal tissue resistance, as well as the degree of heterogeneity in airway constriction. Deep inspirations (DIs) are known to reverse experimentally induced increase in RL, but the mechanism is not entirely clear. The first step toward understanding the effect of DI is to determine how each of the resistance components is affected by DI. In the present study, we measured RL and apparent airway resistance (RAW, which combines the effects of airway resistance and airway heterogeneity) simultaneously before and after a DI in acetylcholine (ACh)-challenged ex vivo sheep lungs. We found that at normal breathing frequency (0.25 Hz) ACh-challenge led to a doubling of RL, 80.3% of that increase was caused by an increase in RAW; the increase in apparent tissue resistance (RT) was insignificant. 57.7% of the increase in RAW was abolished by a single DI. After subtracting RAW from RL, the remaining RT was mostly independent of ACh-challenge and its reduction after a DI came mostly from the change in the mechanical properties of lung parenchyma. We conclude that at normal breathing frequency, RL in an unchallenged lung is mostly composed of RT, and the increase in RL due to ACh-challenge stems mostly from the increase in RAW and that both RAW and RT can be greatly reduced by a DI, likely due to a reduction in true airway resistance and heterogeneity, as well as parenchymal tissue hysteresis post DI.


Assuntos
Resistência das Vias Respiratórias , Tecido Parenquimatoso , Animais , Inalação , Pulmão , Testes de Função Respiratória , Ovinos
4.
Acta Clin Croat ; 60(3): 467-475, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35282489

RESUMO

The aim of the study was to investigate morphological traits of hepatic parenchymal tissue repair in response to injury using the conventional technique (closure) and an innovation method (such as hemostatic medication swab packing and modified batching). The experimental study was carried out on laboratory rats of the Winzar breed using light microscopy, standard stains for micropreparations, and morphometry. Histopathologic examination of micropreparations stained by standard methods revealed pronounced dystrophic processes in hepatocytes located near the necrotic zone (albuminous and hydropic degeneration and chromatin fragmentation in the nuclei). Morphometric studies showed a significant decrease (p<0.001) in almost all indicators of the size of cells and nuclei both near necrosis and distant from it on day 28 of the experiment in the experimental group in comparison to the control group. The results obtained pointed to more intense repair processes when applying the innovation method.


Assuntos
Fígado , Tecido Parenquimatoso , Animais , Humanos , Necrose/patologia , Fenótipo , Ratos
5.
Eur Radiol ; 30(12): 6740-6748, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32691100

RESUMO

OBJECTIVES: To investigate whether contralateral parenchymal enhancement (CPE) on MRI during neoadjuvant endocrine therapy (NET) is associated with the preoperative endocrine prognostic index (PEPI) of ER+/HER2- breast cancer. METHODS: This retrospective observational cohort study included 40 unilateral ER+/HER2- breast cancer patients treated with NET. Patients received NET for 6 to 9 months with MRI response monitoring after 3 and/or 6 months. PEPI was used as endpoint. PEPI is based on surgery-derived pathology (pT- and pN-stage, Ki67, and ER-status) and stratifies patients in three groups with distinct prognoses. Mixed effects and ROC analysis were performed to investigate whether CPE was associated with PEPI and to assess discriminatory ability. RESULTS: The median patient age was 61 (interquartile interval: 52, 69). Twelve patients had PEPI-1 (good prognosis), 15 PEPI-2 (intermediate), and 13 PEPI-3 (poor). High pretreatment CPE was associated with PEPI-3: pretreatment CPE was 39.4% higher on average (95% CI = 1.3, 91.9%; p = .047) compared with PEPI-1. CPE decreased after 3 months in PEPI-2 and PEPI-3. The average reduction was 24.4% (95% CI = 2.6, 41.3%; p = .032) in PEPI-2 and 29.2% (95% CI = 7.8, 45.6%; p = .011) in PEPI-3 compared with baseline. Change in CPE was predictive of PEPI-1 vs PEPI-2+3 (AUC = 0.77; 95% CI = 0.57, 0.96). CONCLUSIONS: CPE during NET is associated with PEPI-group in ER+/HER2- breast cancer: a high pretreatment CPE and a decrease in CPE during NET were associated with a poor prognosis after NET on the basis of PEPI. KEY POINTS: • Change in contralateral breast parenchymal enhancement on MRI during neoadjuvant endocrine therapy distinguished between patients with a good and intermediate/poor prognosis at final pathology. • Patients with a poor prognosis at final pathology showed higher baseline parenchymal enhancement on average compared to patients with a good prognosis. • Patients with an intermediate/poor prognosis at final pathology showed a higher average reduction in parenchymal enhancement after 3 months of neoadjuvant endocrine therapy.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Adulto , Idoso , Mama/patologia , Sistema Endócrino , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos , Resultado do Tratamento
6.
Int Braz J Urol ; 45(1): 150-160, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30620156

RESUMO

OBJECTIVE: To evaluate the renal parenchymal area in human fetuses, providing a descriptive analysis on the renal area development by demographic factors during the second gestational trimester. MATERIAL AND METHODS: We analyzed 84 fetuses (44 males and 40 females), for a total of 168 renal units evaluated in terms of longitudinal length, superior pole width, inferior pole width and thickness. Renal volume was calculated by ellipsoid formula. After renal pelvis dissection, length and width were evaluated; as pelvis is free of urine, we considered thickness as 1mm. Renal pelvis volume was also calculated by ellipsoid formula. Renal parenchymal area was assessed by excluding the volume of the renal pelvis from the total renal volume. We performed the statistical analysis by simple linear regression assessing the association between the variables analyzed with the fetal age. RESULTS: Gestational age ranged from 12 to 23 weeks post conception. Mean renal parenchymal area of the right kidney was 666.22mm3 (45.86 to 2375.35mm3) and for the left kidney was 606.76mm3 (68.63 to 2402.57mm3). No statistical difference was observed between the sides (p-value = 0.3456) or genders (p-value = 0.07429). Linear regression between renal parenchymal volume and gestational age was positive for right kidney (y = 133.74x-1479.94 / r² = 0.4009) and left kidney (y = 149.53x-1761.59 / r² = 0.4591). CONCLUSIONS: The linear regression analysis indicated that renal parenchymal area correlated significantly and positively with fetal age, weight and crown-rump length with no statistical differences between gender or laterality. These growth curves provide a reference for functional volume of the kidney during fetal period.


Assuntos
Feto/anatomia & histologia , Rim/anatomia & histologia , Rim/embriologia , Feminino , Idade Gestacional , Humanos , Masculino , Tamanho do Órgão , Gravidez , Segundo Trimestre da Gravidez , Valores de Referência
7.
Eur Radiol ; 28(11): 4705-4716, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29736850

RESUMO

OBJECTIVES: To assess whether contralateral parenchymal enhancement reproduces as an independent biomarker for patient survival in an independent patient cohort from a different cancer institution. METHODS: This is a HIPAA-compliant IRB approved retrospective study. Patients with ER-positive/HER2-negative operable invasive ductal carcinoma and preoperative dynamic contrast-enhanced MRI were consecutively included between 2005 and 2009. The parenchyma of the breast contralateral to known cancer was segmented automatically on MRI and contralateral parenchymal enhancement (CPE) was calculated. CPE was split into tertiles and tested for association with invasive disease-free survival (IDFS) and overall survival (OS). Propensity score analysis with inverse probability weighting (IPW) was used to adjust CPE for patient and tumour characteristics as well as systemic therapy. RESULTS: Three hundred and two patients were included. The median age at diagnosis was 48 years (interquartile range, 42-57). Median follow-up was 88 months (interquartile range, 76-102); 15/302 (5%) patients died and 37/302 (13%) had a recurrence or died. In context of multivariable analysis, IPW-adjusted CPE was associated with IDFS [hazard ratio (HR) = 0.27, 95% confidence interval (CI) = 0.05-0.68, p = 0.004] and OS (HR = 0.22, 95% CI = 0.00-0.83, p = 0.032). CONCLUSIONS: Contralateral parenchymal enhancement on pre-treatment dynamic contrast-enhanced MRI as an independent biomarker of survival in patients with ER-positive/HER2-negative breast cancer has been upheld in this study. These findings are a promising next step towards a practical and inexpensive test for risk stratification of ER-positive/HER2-negative breast cancer. KEY POINTS: • High parenchymal-enhancement in the disease-free contralateral breast reproduces as biomarker for survival. • This is in patients with ER-positive/HER2-negative breast cancer from an independent cancer centre. • This is independent of patient and pathology parameters and systemic therapy.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Tecido Parenquimatoso/diagnóstico por imagem , Adulto , Idoso , Biomarcadores , Neoplasias da Mama/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Pontuação de Propensão , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida
8.
J Urol ; 197(3 Pt 1): 559-565, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27678298

RESUMO

PURPOSE: The aim of this study was to evaluate histological changes in the tumor-parenchymal interface in clear cell renal cell carcinoma after neoadjuvant axitinib treatment. MATERIALS AND METHODS: We obtained clinical and pathology materials from 23 patients with clear cell renal cell carcinoma treated with neoadjuvant axitinib in a phase II clinical trial and from 23 matched patients with clear cell renal cell carcinoma who underwent upfront surgery. Histology of the tumor pseudocapsule and the peritumor kidney parenchymal change was evaluated and compared between the 2 cohorts. RESULTS: A tumor pseudocapsule was noted in all 23 patients who received neoadjuvant axitinib and in all 23 control patients. Most pseudocapsules were noncontinuous and only partially covered the tumor, including in 17 of 23 axitinib cases (74%) and 19 of 23 controls (83%). In axitinib cases the median thickness of the intrarenal and extrarenal pseudocapsule was 1.4 and 2.4 mm, respectively, which was significantly thicker than in control cases (intrarenal p = 0.0008 and extrarenal p <0.0001). The thickness of the pseudocapsule in axitinib treated cases was more frequently irregular compared to that in controls (16 of 23 or 70% and 9 of 23 or 39%, respectively, p = 0.0746). Inflammation, nephrosclerosis, glomerulosclerosis and arteriosclerosis decreased with increasing distance from the tumor edge in the neoadjuvant axitinib and control groups. CONCLUSIONS: The tumor pseudocapsule becomes irregularly thick after neoadjuvant axitinib therapy. Although axitinib likely evokes a strong fibrous reaction in the tumor-parenchymal interface, it does not affect the frequency of infiltrative tumor invasion to the outside of the pseudocapsule or the degree of atrophic/inflammatory change in tissue surrounding the tumor. These findings support the notion that partial nephrectomy could be safely done in well selected patients after neoadjuvant axitinib.


Assuntos
Antineoplásicos/uso terapêutico , Axitinibe/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Testes de Função Renal , Neoplasias Renais/cirurgia , Masculino , Terapia Neoadjuvante , Resultado do Tratamento
9.
Polymers (Basel) ; 16(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000684

RESUMO

Bamboo is composed of thick-walled fibrous tissue and thin-walled parenchymal tissue. To compare the energy consumption of preparing lignocellulose nanofibrils (LCNF) from these bamboo tissues, the crystallinity, sol. viscosity, morphology and mechanical properties of LCNF at different preparation stages were characterized in detail. It required at least nine homogenization cycles for dissociating the fibrous tissue, but only six cycles for the parenchymal tissue. The average diameter of LCNF isolated from fibrous and parenchymal tissues was 45.1 nm and 36.2 nm, respectively. The tensile strength of the LCNF film prepared from parenchymal tissue reached 142.46 MPa, whereas the film from fibrous tissue reached only 122.82 MPa. Additionally, a metal organic framework (MOF) was used to produce MOF-LCNF film with enhanced UV protection and antibacterial properties. The results indicated that the energy consumption for preparing LCNF from parenchymal tissue is significantly lower than that for preparing LCNF from fibrous tissue. This study offers a low-cost and eco-friendly method for preparing LCNF, promoting the precise utilization of different tissues from bamboo based on their unique characteristics.

10.
Breast ; 60: 230-237, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34763270

RESUMO

PURPOSE: To assess whether contralateral parenchymal enhancement (CPE) on MRI is associated with gene expression pathways in ER+/HER2-breast cancer, and if so, whether such pathways are related to survival. METHODS: Preoperative breast MRIs were analyzed of early ER+/HER2-breast cancer patients eligible for breast-conserving surgery included in a prospective observational cohort study (MARGINS). The contralateral parenchyma was segmented and CPE was calculated as the average of the top-10% delayed enhancement. Total tumor RNA sequencing was performed and gene set enrichment analysis was used to reveal gene expression pathways associated with CPE (N = 226) and related to overall survival (OS) and invasive disease-free survival (IDFS) in multivariable survival analysis. The latter was also done for the METABRIC cohort (N = 1355). RESULTS: CPE was most strongly correlated with proteasome pathways (normalized enrichment statistic = 2.04, false discovery rate = .11). Patients with high CPE showed lower tumor proteasome gene expression. Proteasome gene expression had a hazard ratio (HR) of 1.40 (95% CI = 0.89, 2.16; P = .143) for OS in the MARGINS cohort and 1.53 (95% CI = 1.08, 2.14; P = .017) for IDFS, in METABRIC proteasome gene expression had an HR of 1.09 (95% CI = 1.01, 1.18; P = .020) for OS and 1.10 (95% CI = 1.02, 1.18; P = .012) for IDFS. CONCLUSION: CPE was negatively correlated with tumor proteasome gene expression in early ER+/HER2-breast cancer patients. Low tumor proteasome gene expression was associated with improved survival in the METABRIC data.


Assuntos
Neoplasias da Mama , Complexo de Endopeptidases do Proteassoma , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , Feminino , Expressão Gênica , Humanos , Imageamento por Ressonância Magnética , Prognóstico , Estudos Prospectivos , Complexo de Endopeptidases do Proteassoma/genética , Receptor ErbB-2/genética
11.
Radiol Bras ; 53(2): 95-104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32336824

RESUMO

OBJECTIVE: To evaluate background parenchymal enhancement (BPE) and its characteristics, as well as its behavior before and after neoadjuvant chemotherapy (NAC), in both breasts of patients with unilateral breast cancer. MATERIALS AND METHODS: This was a retrospective, cross-sectional observational study involving a consecutive sample of women with invasive breast cancer who underwent breast magnetic resonance imaging (MRI) between July 2007 and July 2017, as well as undergoing dynamic contrast-enhanced MRI before and after NAC. In both breasts, we evaluated the BPE in accordance with the Breast Imaging Reporting and Data System. We applied logistic regression analysis, and values of p < 0.05 were considered significant. RESULTS: We evaluated 150 women. The mean age was 45.2 years (range, 20-74 years). The variables correlating independently with a high pre-NAC BPE, in the affected and contralateral breasts, were being under 50 years of age (odds ratio [OR] = 6.55; 95% confidence interval [95% CI]: 2.32-18.46, for both breasts) and a post-NAC BPE reduction (OR = 17.75; 95% CI: 4.94-63.73 and OR = 18.47; 95% CI: 5.19-66.49, respectively). CONCLUSION: Patients with invasive unilateral breast cancer who have a high pre-NAC BPE in both breasts tend to be under 50 years of age and to show a post-NAC reduction in BPE.


OBJETIVO: Avaliar o realce de fundo do parênquima (RFP), suas características e seu comportamento pré- e pós-quimioterapia neoadjuvante (QTN) em ambas as mamas em pacientes com câncer de mama unilateral. MATERIAIS E MÉTODOS: Estudo observacional transversal retrospectivo realizado em um serviço acadêmico e um centro especializado em mamas, que incluiu mulheres com câncer de mama invasivo submetidas a QTN e que realizaram exames de ressonância magnética (RM) das mamas com contraste antes e depois da quimioterapia, entre julho de 2007 e julho de 2017. Os exames foram realizados de acordo com protocolo padronizado. O RFP foi avaliado em ambas as mamas de acordo com o ACR BI-RADS, 5ª edição. Foi aplicada análise de regressão logística. O nível de significância adotado para os testes estatísticos foi p < 0,05. RESULTADOS: Foram analisadas 150 mulheres. A idade média foi de 45,2 anos (20­74 anos). Na análise de regressão multivariada, apenas a idade inferior a 50 anos e redução do RFP correlacionaram-se independentemente com o nível alto de RFP em ambas as mamas: mamas afetadas (odds ratio [OR]: 6,55; intervalo de confiança 95% [IC 95%]: 2,32­18,46 e OR: 17,75; IC 95%: 4,94­63,73, respectivamente); mamas contralaterais (OR: 6,55; IC: 95% 2,32­18,46 e OR: 18,47; IC 95%: 5,19­66,49, respectivamente). CONCLUSÃO: Idade abaixo de 50 anos e redução do RFP pós-QTN correlacionaram-se independentemente com maior RFP pré-QTN em ambas as mamas em pacientes com câncer de mama invasivo unilateral submetidas a QTN.

12.
J Appl Physiol (1985) ; 123(1): 79-87, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28450548

RESUMO

As a normal part of mature aging, lung tissue undergoes microstructural changes such as alveolar air-space enlargement and redistribution of collagen and elastin away from the alveolar duct. The older lung also experiences an associated decrease in elastic recoil pressure and an increase in specific tissue elastic moduli, but how this relates mechanistically to microstructural remodeling is not well-understood. In this study, we use a structure-based mechanics analysis to elucidate the contributions of age-related air-space enlargement and redistribution of elastin and collagen to loss of lung elastic recoil pressure and increase in tissue elastic moduli. Our results show that age-related geometric changes can result in reduction of elastic recoil pressure and increase in shear and bulk moduli, which is consistent with published experimental data. All elastic moduli were sensitive to the distribution of stiffness (representing elastic fiber density) in the alveolar wall, with homogenous stiffness near the duct and through the septae resulting in a more compliant tissue. The preferential distribution of elastic proteins around the alveolar duct in the healthy young adult lung therefore provides for a more elastic tissue.NEW & NOTEWORTHY We use a structure-based mechanics analysis to correlate air-space enlargement and redistribution of elastin and collagen to age-related changes in the mechanical behavior of lung parenchyma. Our study highlights that both the cause (redistribution of elastin and collagen) and the structural effect (alveolar air-space enlargement) contribute to decline in lung tissue elastic recoil with age; these results are consistent with published data and provide a new avenue for understanding the mechanics of the older lung.


Assuntos
Envelhecimento/fisiologia , Elasticidade/fisiologia , Modelos Anatômicos , Alvéolos Pulmonares/anatomia & histologia , Alvéolos Pulmonares/fisiologia , Estresse Mecânico , Envelhecimento/patologia , Dilatação/efeitos adversos , Humanos , Pulmão/anatomia & histologia , Pulmão/patologia , Pulmão/fisiologia , Pessoa de Meia-Idade , Pressão/efeitos adversos , Alvéolos Pulmonares/patologia , Fenômenos Fisiológicos Respiratórios , Tensão Superficial , Adulto Jovem
13.
Healthc Technol Lett ; 4(5): 204-209, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29184666

RESUMO

In laparoscopic surgery, the surgeon must operate with a limited field of view and reduced depth perception. This makes spatial understanding of critical structures difficult, such as an endophytic tumour in a partial nephrectomy. Such tumours yield a high complication rate of 47%, and excising them increases the risk of cutting into the kidney's collecting system. To overcome these challenges, an augmented reality guidance system is proposed. Using intra-operative ultrasound, a single navigation aid, and surgical instrument tracking, four augmentations of guidance information are provided during tumour excision. Qualitative and quantitative system benefits are measured in simulated robot-assisted partial nephrectomies. Robot-to-camera calibration achieved a total registration error of 1.0 ± 0.4 mm while the total system error is 2.5 ± 0.5 mm. The system significantly reduced healthy tissue excised from an average (±standard deviation) of 30.6 ± 5.5 to 17.5 ± 2.4 cm3 (p < 0.05) and reduced the depth from the tumor underside to cut from an average (±standard deviation) of 10.2 ± 4.1 to 3.3 ± 2.3 mm (p < 0.05). Further evaluation is required in vivo, but the system has promising potential to reduce the amount of healthy parenchymal tissue excised.

14.
Front Plant Sci ; 7: 834, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27379127

RESUMO

Polyamines are small basic compounds present in all living organisms and act in a variety of biological processes. However, the mechanism of polyamine sensing, signaling and response in relation to other metabolic pathways remains to be fully addressed in plant cells. As one approach, we isolated Arabidopsis mutants that show increased resistance to spermine in terms of chlorosis. We show here that two of the mutants have a point mutation in a nitrate transporter gene of the NRT1/PTR family (NPF), NRT1.3 (AtNPF6.4). These mutants also exhibit increased resistance to putrescine and spermidine while loss-of-function mutants of the two closest homologs of NRT1.3, root-specific NRT1.1 (AtNPF6.3) and petiole-specific NRT1.4 (AtNPF6.2), were shown to have a normal sensitivity to polyamines. When the GUS reporter gene was expressed under the control of the NRT1.3 promoter, GUS staining was observed in leaf mesophyll cells and stem cortex cells but not in the epidermis, suggesting that NRT1.3 specifically functions in parenchymal tissues. We further found that the aerial part of the mutant seedling has normal levels of polyamines but shows reduced uptake of norspermidine compared with the wild type. These results suggest that polyamine transport or metabolism is associated with nitrate transport in the parenchymal tissue of the shoot.

15.
Radiol. bras ; 53(2): 95-104, Mar.-Apr. 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1098562

RESUMO

Abstract Objective: To evaluate background parenchymal enhancement (BPE) and its characteristics, as well as its behavior before and after neoadjuvant chemotherapy (NAC), in both breasts of patients with unilateral breast cancer. Materials and Methods: This was a retrospective, cross-sectional observational study involving a consecutive sample of women with invasive breast cancer who underwent breast magnetic resonance imaging (MRI) between July 2007 and July 2017, as well as undergoing dynamic contrast-enhanced MRI before and after NAC. In both breasts, we evaluated the BPE in accordance with the Breast Imaging Reporting and Data System. We applied logistic regression analysis, and values of p < 0.05 were considered significant. Results: We evaluated 150 women. The mean age was 45.2 years (range, 20-74 years). The variables correlating independently with a high pre-NAC BPE, in the affected and contralateral breasts, were being under 50 years of age (odds ratio [OR] = 6.55; 95% confidence interval [95% CI]: 2.32-18.46, for both breasts) and a post-NAC BPE reduction (OR = 17.75; 95% CI: 4.94-63.73 and OR = 18.47; 95% CI: 5.19-66.49, respectively). Conclusion: Patients with invasive unilateral breast cancer who have a high pre-NAC BPE in both breasts tend to be under 50 years of age and to show a post-NAC reduction in BPE.


Resumo Objetivo: Avaliar o realce de fundo do parênquima (RFP), suas características e seu comportamento pré- e pós-quimioterapia neoadjuvante (QTN) em ambas as mamas em pacientes com câncer de mama unilateral. Materiais e Métodos: Estudo observacional transversal retrospectivo realizado em um serviço acadêmico e um centro especializado em mamas, que incluiu mulheres com câncer de mama invasivo submetidas a QTN e que realizaram exames de ressonância magnética (RM) das mamas com contraste antes e depois da quimioterapia, entre julho de 2007 e julho de 2017. Os exames foram realizados de acordo com protocolo padronizado. O RFP foi avaliado em ambas as mamas de acordo com o ACR BI-RADS, 5ª edição. Foi aplicada análise de regressão logística. O nível de significância adotado para os testes estatísticos foi p < 0,05. Resultados: Foram analisadas 150 mulheres. A idade média foi de 45,2 anos (20-74 anos). Na análise de regressão multivariada, apenas a idade inferior a 50 anos e redução do RFP correlacionaram-se independentemente com o nível alto de RFP em ambas as mamas: mamas afetadas (odds ratio [OR]: 6,55; intervalo de confiança 95% [IC 95%]: 2,32-18,46 e OR: 17,75; IC 95%: 4,94-63,73, respectivamente); mamas contralaterais (OR: 6,55; IC: 95% 2,32-18,46 e OR: 18,47; IC 95%: 5,19-66,49, respectivamente). Conclusão: Idade abaixo de 50 anos e redução do RFP pós-QTN correlacionaram-se independentemente com maior RFP pré-QTN em ambas as mamas em pacientes com câncer de mama invasivo unilateral submetidas a QTN.

16.
Int. braz. j. urol ; 45(1): 150-160, Jan.-Feb. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989962

RESUMO

ABSTRACT Objective: To evaluate the renal parenchymal area in human fetuses, providing a descriptive analysis on the renal area development by demographic factors during the second gestational trimester. Material and Methods: We analyzed 84 fetuses (44 males and 40 females), for a total of 168 renal units evaluated in terms of longitudinal length, superior pole width, inferior pole width and thickness. Renal volume was calculated by ellipsoid formula. After renal pelvis dissection, length and width were evaluated; as pelvis is free of urine, we considered thickness as 1mm. Renal pelvis volume was also calculated by ellipsoid formula. Renal parenchymal area was assessed by excluding the volume of the renal pelvis from the total renal volume. We performed the statistical analysis by simple linear regression assessing the association between the variables analyzed with the fetal age. Results: Gestational age ranged from 12 to 23 weeks post conception. Mean renal parenchymal area of the right kidney was 666.22mm3 (45.86 to 2375.35mm3) and for the left kidney was 606.76mm3 (68.63 to 2402.57mm3). No statistical difference was observed between the sides (p-value = 0.3456) or genders (p-value = 0.07429). Linear regression between renal parenchymal volume and gestational age was positive for right kidney (y = 133.74x-1479.94 / r2 = 0.4009) and left kidney (y = 149.53x-1761.59 / r2 = 0.4591). Conclusions: The linear regression analysis indicated that renal parenchymal area correlated significantly and positively with fetal age, weight and crown-rump length with no statistical differences between gender or laterality. These growth curves provide a reference for functional volume of the kidney during fetal period.


Assuntos
Humanos , Masculino , Feminino , Feto/anatomia & histologia , Rim/anatomia & histologia , Rim/embriologia , Tamanho do Órgão , Segundo Trimestre da Gravidez , Valores de Referência , Idade Gestacional
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