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OBJECTIVE: Assess the significance of enlarged lateral lymph nodes (LLN) for disease recurrence, metastasis, and organ preservation in patients with rectal cancer. BACKGROUND: Optimal treatment of rectal adenocarcinoma involving LLN is subject to debate. METHODS: A post hoc analysis of the OPRA trial, a multicenter study of patients with rectal cancer treated with total neoadjuvant therapy (TNT) followed by total mesorectal excision or watch-and-wait management. We analyzed the association of visible LLN (LLN+), LLN≥7 mm (short axis) on baseline MRI, and LLN≥4 mm on restaging MRI with recurrence, metastasis, and rectum preservation. RESULTS: At baseline, 57 out of 324 (18%) patients had LLN+. In 30 (53%) of 57 patients with LLN+ on baseline MRI, the LLN disappeared after TNT. Disease recurrence in LLN was rare (3.5% of patients with LLN+ and 0.4% of patients with LLN-). All patients with recurrence in LLN also had distant metastasis. The rate of organ preservation was significantly lower in patients with LLN≥4 mm on restaging MRI (P=0.013). We found no significant differences in rates of local recurrence or metastasis between patients with LLN+ vs. LLN- and in patients with LLN≥7 vs.<7 mm on baseline MRI. LLN dissection was performed in 3 patients; 2 of them died of distant metastasis. CONCLUSIONS: LLN involvement is not associated with disease recurrence or metastasis, but persistence of LLN≥4 mm after TNT is negatively associated with rectum preservation in patients with locally advanced rectal cancer treated with TNT. Dissection of lateral nodes likely benefits few patients.
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Systems medicine (SM) has emerged as a powerful tool for studying the human body at the systems level with the aim of improving our understanding, prevention and treatment of complex diseases. Being able to automatically extract relevant features needed for a given task from high-dimensional, heterogeneous data, deep learning (DL) holds great promise in this endeavour. This review paper addresses the main developments of DL algorithms and a set of general topics where DL is decisive, namely, within the SM landscape. It discusses how DL can be applied to SM with an emphasis on the applications to predictive, preventive and precision medicine. Several key challenges have been highlighted including delivering clinical impact and improving interpretability. We used some prototypical examples to highlight the relevance and significance of the adoption of DL in SM, one of them is involving the creation of a model for personalized Parkinson's disease. The review offers valuable insights and informs the research in DL and SM.
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Aprendizado Profundo , Análise de Sistemas , Algoritmos , Biomarcadores/metabolismo , Doença/classificação , Registros Eletrônicos de Saúde , Genômica , Humanos , Metabolômica , Redes Neurais de Computação , Medicina de Precisão/métodos , Proteômica , TranscriptomaRESUMO
In recent years, several key advances in the management of locally advanced rectal cancer have been made, including the implementation of total mesorectal excision as the standard surgical approach; use of neoadjuvant chemoradiotherapy in selected patients with a high risk of local recurrence, and finally, adoption of organ preservation strategies, through either local excision or nonoperative management in selected patients with clinical complete response following neoadjuvant chemoradiotherapy. This review aims to shed light on the role of rectal MRI in the assessment of treatment response after neoadjuvant therapy, which is especially important given the growing feasibility of nonoperative management. First, an overview of current neoadjuvant therapies and response assessment based on digital rectal examination, endoscopy, and MRI will be provided. Second, the use of a high-quality restaging rectal MRI protocol will be presented. Third, a step-by-step approach to assessing treatment response on restaging rectal MRI following neoadjuvant treatment will be outlined, acknowledging challenges faced by radiologists during MRI interpretation. Finally, research related to response assessment will be discussed. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.
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Terapia Neoadjuvante , Neoplasias Retais , Humanos , Terapia Neoadjuvante/métodos , Quimiorradioterapia/métodos , Estadiamento de Neoplasias , Reto/diagnóstico por imagem , Reto/patologia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Imageamento por Ressonância Magnética , Resultado do Tratamento , Recidiva Local de Neoplasia/diagnóstico por imagemRESUMO
BACKGROUND. Patients with nonmucinous rectal adenocarcinoma may develop mucinous changes after neoadjuvant chemoradiotherapy, which are described as mucinous degeneration. The finding's significance in earlier studies has varied. OBJECTIVE. The purpose of this study was to assess the frequency of mucinous degeneration on MRI after neoadjuvant therapy for rectal adenocarcinoma and to compare outcomes among patients with nonmucinous tumor, mucinous tumor, and mucinous degeneration on MRI. METHODS. This retrospective study included 201 patients (83 women, 118 men; mean age, 61.8 ± 2.2 [SD] years) with rectal adenocarcinoma who underwent neoadjuvant chemoradiotherapy followed by total mesorectal excision from October 2011 to November 2015, underwent baseline and restaging rectal MRI examinations, and had at least 2 years of follow-up. Two radiologists independently evaluated MRI examinations for mucin content, which was defined as T2 hyperintensity in the tumor or tumor bed, and resolved differences by consensus. Patients were classified into three groups on the basis of mucin status: those with nonmucinous tumor (≤ 50% mucin content on baseline and restaging examinations), those with mucinous tumor (> 50% mucin content on baseline and restaging examinations), and those with mucinous degeneration (≤ 50% mucin content on baseline examination and > 50% content on restaging examination). The three groups were compared. RESULTS. Interreader agreement for mucin content, expressed as a kappa coefficient, was 0.893 on baseline MRI and 0.890 on restaging MRI. Of the 201 patients, 156 (77.6%) had nonmucinous tumor, 34 (16.9%) had mucinous tumor, and 11 (5.5%) had mucinous degeneration. Mucin status was not significantly associated with complete pathologic response (p = .41) or local or distant recurrence (both p > .05). The death rate during follow-up was not significantly different (p = .21) between patients with nonmucinous tumor (23.1%), those with mucinous tumor (29.4%), and those with mucinous degeneration (9.1%). In adjusted Cox regression analysis, with mucinous degeneration used as reference, the HR for the overall survival rate for the mucinous tumor group was 4.7 (95% CI, 0.6-38.3; p = .14), and that for the nonmucinous tumor group was 8.0 (95% CI, 0.9-59.9; p = .06). On histopathologic assessment, all 11 patients with mucinous degeneration showed acellular mucin, yet 10 of 11 patients showed viable tumor (i.e., in nonmucinous portions of the tumors). CONCLUSION. Mucinous degeneration on MRI is not significantly associated with pathologic complete response, recurrence, or survival. CLINICAL IMPACT. Mucinous degeneration on MRI is uncommon and should not be deemed an indicator of pathologic complete response.
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Adenocarcinoma Mucinoso , Neoplasias Retais , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Resultado do Tratamento , Estudos Retrospectivos , Adenocarcinoma Mucinoso/diagnóstico por imagem , Adenocarcinoma Mucinoso/terapia , Quimiorradioterapia/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Imageamento por Ressonância Magnética , Mucinas , Estadiamento de NeoplasiasRESUMO
A linear electromagnetic energy harvesting device for underwater applications, fabricated with a simple manufacturing process, was developed to operate with movement frequencies from 0.1 to 0.4 Hz. The generator has two coils, and the effect of the combination of the two coils was investigated. The experimental study has shown that the energy capture system was able to supply energy to several ocean sensors, producing 7.77 mJ per second with wave movements at 0.4 Hz. This study shows that this energy is enough to restore the energy used by the battery or the capacitor and continue supplying energy to the sensors used in the experimental work. For an ocean wave frequency of 0.4 Hz, the generator can supply power to 8 sensors or 48 sensors, depending on the energy consumed and its optimization.
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Fontes de Energia Elétrica , Movimento , Fenômenos FísicosRESUMO
BACKGROUND: It is known that drug shortages represent a major challenge for all stakeholders involved in the process, but there is little evidence regarding insights into patients' awareness and perspectives. This study aimed to investigate the patients-perceived drug shortages experience and their view on outcomes in different European hospital settings. Furthermore, we wanted to explore information preferences on drug shortages. METHODS: A retrospective, cross sectional, a mixed method study was conducted in six European hospital settings. One hospital (H) from each of this country agreed to participate: Bosnia and Herzegovina (H-BiH), Croatia (H-CR), Germany (H-GE), Greece (H-GR), Serbia (H-SE) and Poland (H-PO). Recruitment and data collection was conducted over 27 months from November 2017 until January 2020. Overall, we surveyed 607 patients which completed paper-based questionnaire. Questions related to: general information (demographic data), basic knowledge on drug shortages, drug shortages experienced during hospitalization and information preferences on drug shortage. Differences between hospital settings were analyzed using Chi-squared test or Fisher's exact test. For more complex contingency tables, Monte Carlo simulations (N = 2000) were applied for Fisher's test. Post-hoc hospital-wise analyses were performed using Fisher's exact tests. False discovery rate was controlled using the Bonferroni method. Analyses were performed using R: a language and environment for statistical computing (v 3.6.3). RESULTS: 6 % of patients reported experiences with drug shortages while hospitalized which led to a deterioration of their health. The majority of affected patients were hospitalized at hematology and/or oncology wards in H-BiH, H-PO and H-GE. H-BiH had the highest number of affected patients (18.1 %, N = 19/105, p < 0.001) while the fewest patients were in H-SE (1 %, N = 1/100, p = 0.001). In addition, 82.5 %, (N = 501/607) of respondents wanted to be informed of alternative treatment options if there was a drug shortage without a generic substitute available. Majority of these patients (66.4 %, N = 386/501) prefer to be informed by a healthcare professional. CONCLUSIONS: Although drug shortages led to serious medical consequences, our findings show that most of the patients did not perceive shortages as a problem. One possible interpretation is that good hospital management practices by healthcare professionals helped to mitigate the perceived impact of shortages. Our study highlights the importance of a good communication especially between patients and healthcare professionals in whom our patients have the greatest trust.
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Medicamentos Genéricos , Hospitais , Estudos Transversais , Alemanha , Grécia , Humanos , Polônia , Estudos RetrospectivosRESUMO
Intestinal mucositis, characterized by inflammatory and/or ulcerative processes in the gastrointestinal tract, occurs due to cellular and tissue damage following treatment with 5-fluorouracil (5-FU). Rutin (RUT), a natural flavonoid extracted from Dimorphandra gardneriana, exhibits antioxidant, anti-inflammatory, cytoprotective, and gastroprotective properties. However, the effect of RUT on inflammatory processes in the intestine, especially on mucositis promoted by antineoplastic agents, has not yet been reported. In this study, we investigated the role of RUT on 5-FU-induced experimental intestinal mucositis. Swiss mice were randomly divided into seven groups: Saline, 5-FU, RUT-50, RUT-100, RUT-200, Celecoxib (CLX), and CLX + RUT-200 groups. The mice were weighed daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis); malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH) concentrations; mast and goblet cell counts; and cyclooxygenase-2 (COX-2) activity, as well as to perform immunohistochemical analyses. RUT treatment (200 mg/kg) prevented 5-FU-induced histopathological changes and reduced oxidative stress by decreasing MDA concentrations and increasing GSH concentrations. RUT attenuated the inflammatory response by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. These results suggest that the COX-2 pathway is one of the underlying protective mechanisms of RUT against 5-FU-induced intestinal mucositis.
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Fluoruracila/efeitos adversos , Enteropatias , Mucosite , Estresse Oxidativo/efeitos dos fármacos , Rutina/farmacologia , Animais , Fluoruracila/farmacologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Enteropatias/induzido quimicamente , Enteropatias/tratamento farmacológico , Enteropatias/metabolismo , Enteropatias/patologia , Masculino , Camundongos , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/metabolismo , Mucosite/patologiaRESUMO
Marine biofouling has severe economic impacts and cyanobacteria play a significant role as early surface colonizers. Despite this fact, cyanobacterial biofilm formation studies in controlled hydrodynamic conditions are scarce. In this work, computational fluid dynamics was used to determine the shear rate field on coupons that were placed inside the wells of agitated 12-well microtiter plates. Biofilm formation by three different cyanobacterial strains was assessed at two different shear rates (4 and 40 s-1 ) which can be found in natural ecosystems and using different surfaces (glass and perspex). Biofilm formation was higher under low shear conditions, and differences obtained between surfaces were not always statistically significant. The hydrodynamic effect was more noticeable during the biofilm maturation phase rather than during initial cell adhesion and optical coherence tomography showed that different shear rates can affect biofilm architecture. This study is particularly relevant given the cosmopolitan distribution of these cyanobacterial strains and the biofouling potential of these organisms.
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Biofilmes , Cianobactérias/fisiologia , HidrodinâmicaRESUMO
BACKGROUND: There is a need to find an effective treatment against reperfusion injury. The aim of the present study was to evaluate the capacity of the ischemic postconditioning and statin to prevent renal reperfusion injury. DESIGN AND SETTING: An experimental study developed at Universidade Anhanguera-Uniderp. METHODS: A total of 41 Wistar rats were distributed into 5 groups: ischemia and reperfusion (I/R), ischemic postconditioning (IPC), postconditioning + statin (IPC + S), statin (S), and sham. In the sham group, the infrarenal abdominal aorta was dissected and isolated; all others were submitted to aortic clamping for 70 min (ischemia) and posterior removal of the clamp (reperfusion, 70 min). In the IPC and IPC + S groups, postconditioning was performed in ischemia and reperfusion phases by 4 cycles of reperfusion and ischemia lasting 30 sec each. In the IPC + S and S groups, preceding the surgical procedure, atorvastatin was administered 3.4 mg/day for 7 days by gavage. After the procedure, the left kidney was removed for histological study. RESULTS: The mean renal lesion was 4 in the I/R group, 2.44 in the IPC group, 1.22 in the IPC + S group, 1.11 in the S group, and 1 in the sham group. The I/R group had a higher degree of tissue injury when compared to the others (P < 0.001) and the IPC + S and S groups improved protection against IPC alone (P < 0.05). CONCLUSIONS: Ischemic postconditioning and atorvastatin can minimize renal remote reperfusion injury.
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Aorta Abdominal/cirurgia , Atorvastatina/farmacologia , Pós-Condicionamento Isquêmico/métodos , Nefropatias/prevenção & controle , Rim/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Terapia Combinada , Citoproteção , Modelos Animais de Doenças , Rim/patologia , Nefropatias/patologia , Masculino , Ratos Wistar , Fluxo Sanguíneo Regional , Traumatismo por Reperfusão/patologia , Fatores de TempoRESUMO
BACKGROUND: Biomechanical gait changes are proposed as adaptations to medial knee osteoarthritis (OA), and little is known about which parameters can be modified early by high tibial osteotomy (HTO) surgery. The aim of this study was to identify early gait changes in a postoperative period of 6 months as compared to a control group, in three different spatial planes. METHODS: Twenty-one patients with OA were submitted to three-dimensional gait analysis preoperatively and 6 months after HTO surgery. Sixteen healthy individuals were selected for the control group. RESULTS: Compared to the control group, OA patients walked more slowly, with a shorter stride length, and with a higher knee varus and flexion angles. The gait changes detected in the postoperative of 6 months were a significant reduction in knee varus angle and adductor moment in coronal plane; an important reduction in knee extension and an increased extensor moment in sagittal plane; also an increased foot external rotation angle in axial plane was observed. Flexion angle peak in swing phase, adductor and flexor moments were the gait parameters with postoperatively results that were closer to those of the control group. CONCLUSIONS: Even in a short follow-up of 6 months, HTO determines positive results in biomechanical gait, not only in the coronal plane but also in the sagittal and axial planes and should be taken into account during the rehabilitation process.
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Análise da Marcha , Osteoartrite do Joelho/fisiopatologia , Osteotomia , Tíbia/fisiopatologia , Adulto , Fenômenos Biomecânicos , Seguimentos , Marcha , Humanos , Articulação do Joelho/fisiologia , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Tíbia/cirurgiaRESUMO
Peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) is a highly specific molecular method widely used for microbial identification. Nonetheless, and due to the detection limit of this technique, a time-consuming pre-enrichment step is typically required before identification. In here we have developed a lab-on-a-chip device to concentrate cell suspensions and speed up the identification process in yeasts. The PNA-FISH protocol was optimized to target Saccharomyces cerevisiae, a common yeast that is very relevant for several types of food industries. Then, several coin-sized microfluidic devices with different geometries were developed. Using Computational fluid dynamics (CFD), we modeled the hydrodynamics inside the microchannels and selected the most promising options. SU-8 structures were fabricated based on the selected designs and used to produce polydimethylsiloxane-based microchips by soft lithography. As a result, an integrated approach combining microfluidics and PNA-FISH for the rapid identification of S. cerevisiae was achieved. To improve fluid flow inside microchannels and the PNA-FISH labeling, oxygen plasma treatment was applied to the microfluidic devices and a new methodology to introduce the cell suspension and solutions into the microchannels was devised. A strong PNA-FISH signal was observed in cells trapped inside the microchannels, proving that the proposed methodology works as intended. The microfluidic designs and PNA-FISH procedure described in here should be easily adaptable for detection of other microorganisms of similar size.
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Hibridização in Situ Fluorescente/instrumentação , Dispositivos Lab-On-A-Chip , Ácidos Nucleicos Peptídicos/metabolismo , Saccharomyces cerevisiae/isolamento & purificação , Desenho de Equipamento , Oxigênio/química , Gases em Plasma/química , Saccharomyces cerevisiae/metabolismoRESUMO
Gas embolisms can hinder blood flow and lead to occlusion of the vessels and ischemia. Bubbles in microvessels circulate as tubular bubbles (Taylor bubbles) and can be trapped, blocking the normal flow of blood. To understand how Taylor bubbles flow in microcirculation, in particular, how bubbles disturb the blood flow at the scale of blood cells, experiments were performed in microchannels at a low Capillary number. Bubbles moving with a stream of in vitro blood were filmed with the help of a high-speed camera. Cell-free layers (CFLs) were observed downstream of the bubble, near the microchannel walls and along the centerline, and their thicknesses were quantified. Upstream to the bubble, the cell concentration is higher and CFLs are less clear. While just upstream of the bubble the maximum RBC concentration happens at positions closest to the wall, downstream the maximum is in an intermediate region between the centerline and the wall. Bubbles within microchannels promote complex spatio-temporal variations of the CFL thickness along the microchannel with significant relevance for local rheology and transport processes. The phenomenon is explained by the flow pattern characteristic of low Capillary number flows. Spatio-temporal variations of blood rheology may have an important role in bubble trapping and dislodging.
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Dispositivos Lab-On-A-Chip , Microbolhas , ReologiaRESUMO
Cell therapy is a promising approach to improve cartilage healing. Adipose tissue is an abundant and readily accessible cell source. Previous studies have demonstrated good cartilage repair results with adipose tissue mesenchymal stem cells in small animal experiments. This study aimed to examine these cells in a large animal model. Thirty knees of adult sheep were randomly allocated to three treatment groups: CELLS (scaffold seeded with human adipose tissue mesenchymal stem cells), SCAFFOLD (scaffold without cells), or EMPTY (untreated lesions). A partial thickness defect was created in the medial femoral condyle. After six months, the knees were examined according to an adaptation of the International Cartilage Repair Society (ICRS 1) score, in addition to a new Partial Thickness Model scale and the ICRS macroscopic score. All of the animals completed the follow-up period. The CELLS group presented with the highest ICRS 1 score (8.3 ± 3.1), followed by the SCAFFOLD group (5.6 ± 2.2) and the EMPTY group (5.2 ± 2.4) (p = 0.033). Other scores were not significantly different. These results suggest that human adipose tissue mesenchymal stem cells promoted satisfactory cartilage repair in the ovine model.
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Tecido Adiposo/citologia , Condrócitos/citologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Regeneração/fisiologia , Tecido Adiposo/imunologia , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Cartilagem Articular/lesões , Cartilagem Articular/cirurgia , Diferenciação Celular , Condrócitos/imunologia , Feminino , Expressão Gênica , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Humanos , Células-Tronco Mesenquimais/imunologia , Ovinos , Joelho de Quadrúpedes/lesões , Joelho de Quadrúpedes/cirurgia , Engenharia Tecidual , Alicerces Teciduais , Transplante Heterólogo , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the efficacy and safety of sliding osteotomy of the lateral epicondyle in correcting rigid valgus deformity in knee arthroplasty. METHODS: A retrospective study of patients undergoing total knee arthroplasty with lateral epicondyle sliding osteotomy between 2006 and 2018. The main outcome was the incidence of complications and adverse events. Secondary outcomes were Visual Analog Scale for Pain, varus stress test, and varus knee thrust during gait. RESULTS: 19 knees (19 participants) were included in the study. The mean follow-up was 4.2 years. There were no cases of infection or reoperation due to instability. Two participants (10.5%) had mild or moderate knee pain (VAS pain = 4.6 ± 1.9). Two arthroplasties (10.5%) had mild varus stress. No participant presented varus thrust. CONCLUSION: Sliding osteotomy of the lateral epicondyle allows fast and safe ligament balance of knee valgus deformities. Level of Evidence I, Case series.
Avaliar a eficácia e a segurança da osteotomia de deslizamento do epicôndilo lateral na correção da deformidade em valgo rígida na artroplastia de joelho. Métodos: Estudo retrospectivo de pacientes submetidos à artroplastia total do joelho com osteotomia de deslizamento do epicôndilo lateral entre 2006 e 2018. O principal desfecho foi a incidência de complicações e eventos adversos. Os desfechos secundários foram escala visual analógica para dor, teste de estresse em varo e flambagem em varo do joelho durante a marcha. Resultados: Foram incluídos no estudo 19 joelhos (19 participantes). O seguimento médio foi de 4,2 anos. Não houve nenhum caso de infecção ou reoperação devido à instabilidade. Dois participantes (10,5%) apresentaram algum tipo de dor leve ou moderada no joelho (EVA = 4,6 ± 1,9). Duas artroplastias (10,5%) apresentaram estresse em varo leve. Nenhum participante apresentou flambagem em varo. Conclusão: A osteotomia de deslizamento do epicôndilo lateral possibilitou o balanço ligamentar das deformidades em valgo do joelho de forma rápida e segura. Nível de Evidência IV, Série de Casos.
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This comprehensive review explores a wide range of imaging findings associated with the gallbladder (GB), from anatomic variants to rare diseases. Through an in-depth review of diagnostic modalities including ultrasound, magnetic resonance cholangiopancreatography, CT, and MRI, we aim to highlight the crucial role of imaging techniques in diagnosing GB disorders, as congenital anomalies, inflammatory diseases, neoplasms, and surgical complications. Employing a detailed analysis and comparison of imaging findings across various modalities, this review seeks to improve diagnostic accuracy for GB-related pathologies, facilitating optimal patient management.
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In vitro platforms capable of mimicking the hydrodynamic conditions prevailing in natural aquatic environments have been previously validated and used to predict the fouling behavior on different surfaces. Computational Fluid Dynamics (CFD) has been used to predict the shear forces occurring in these platforms. In general, these predictions are made for the initial stages of biofilm formation, where the amount of biofilm does not affect the flow behavior, enabling the estimation of the shear forces that initial adhering organisms have to withstand. In this work, we go a step further in understanding the flow behavior when a mature biofilm is present in such platforms to better understand the shear rate distribution affecting marine biofilms. Using 3D images obtained by Optical Coherence Tomography, a mesh was produced and used in CFD simulations. Biofilms of two different marine cyanobacteria were developed in agitated microtiter plates incubated at two different shaking frequencies for 7 weeks. The biofilm-flow interactions were characterized in terms of the velocity field and shear rate distribution. Results show that global hydrodynamics imposed by the different shaking frequencies affect biofilm architecture and also that this architecture affects local hydrodynamics, causing a large heterogeneity in the shear rate field. Biofilm cells located in the streamers of the biofilm are subjected to much higher shear values than those located on the bottom of the streamers and this dispersion in shear rate values increases at lower bulk fluid velocities. This heterogeneity in the shear force field may be a contributing factor for the heterogeneous behavior in metabolic activity, growth status, gene expression pattern, and antibiotic resistance often associated with nutrient availability within the biofilm.
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Organotropism has been known since 1889, yet this vital component of metastasis has predominantly stayed elusive. This mini-review gives an overview of the current understanding of the underlying mechanisms of organotropism and metastases development by focusing on the formation of the pre-metastatic niche, immune defenses against metastases, and genomic alterations associated with organotropism. The particular case of brain metastases is also addressed, as well as the impact of organotropism in cancer therapy. The limited comprehension of the factors behind organotropism underscores the necessity for efficient strategies and treatments to manage metastases.
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Colorectal cancer is the third most common cancer and the second leading cause of cancer-related death. Rectal cancer accounts for approximately one-third of new colorectal cancer cases, with adenocarcinoma as the predominant subtype. Despite an overall decline in colorectal cancer incidence and mortality, due to advancements in screening, early diagnosis, and treatment options, there is a concerning increase in incidence rates among young patients. Recent significant advances in managing locally advanced rectal cancer, such as the establishment of different surgical approaches, neoadjuvant treatment using different protocols for high-risk cases, and the adoption of organ-preservation strategies, have increased the importance of the role played by radiologists in locoregional assessment on magnetic resonance imaging at baseline, at restaging, and during active surveillance of patients with rectal cancer. In this article, we review the role of restaging rectal magnetic resonance imaging after neoadjuvant therapy, providing radiologists with a practical, step-by-step guide for assessing treatment response.
O câncer colorretal é o terceiro câncer mais comum e a segunda principal causa de morte relacionada ao câncer. O câncer retal representa aproximadamente um terço dos novos casos de câncer colorretal, sendo o adenocarcinoma o subtipo predominante. Apesar de uma diminuição geral na incidência e mortalidade, impulsionada por avanços na prevenção do câncer, diagnóstico precoce e opções de tratamento aprimoradas, há uma preocupante elevação nas taxas entre os pacientes jovens. Avanços recentes significativos no manejo do câncer retal localmente avançado, como abordagens cirúrgicas, o uso de diferentes protocolos de tratamento neoadjuvante para casos de alto risco e a adoção de estratégias de preservação de órgãos, aumentaram o papel dos radiologistas na avaliação locorregional por meio da ressonância magnética na avaliação inicial, reestadiamento e vigilância ativa de pacientes com câncer retal. Este manuscrito tem como objetivo revisar o papel da ressonância magnética retal no reestadiamento após terapia neoadjuvante, fornecendo aos radiologistas um guia prático para revisar exames nesse contexto.
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Chloraluminium phthalocyanine (ClAlPc) has potential therapeutic effect for the treatment of cancer; however, the molecule is lipophilic and may present self-aggregation which limits its clinical success. Thus, nanocarriers like liposomes can improve ClAlPc solubility, reduce off-site toxicity and increase circulation time. For this purpose, developing suitable liposomes requires the evaluation of different lipid compositions. Herein, we aimed to develop liposomes containing soy phosphatidylcholine (SPC), 1,2-distearoyl-sn-glycero- 3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPEPEG2000), cholesterol and oleic acid loaded with ClAlPc using the surface response methodology and the Box-Behnken design. Liposomes with particle size from 110.93 to 374.97 nm and PdI from 0.265 to 0.468 were obtained. The optimized formulation resulted in 69.09 % of ClAlPc encapsulated, with particle size and polydispersity index, respectively, at 153.20 nm and 0.309, providing stability and aggregation control. Atomic force microscopy revealed vesicles in a spherical or almost spherical shape, while the analyzes by Differential Scanning Calorimetry (DSC), Powder X-ray Diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) suggested that the drug was adequately incorporated into the lipid bilayer of liposomes, in its amorphous state or molecularly dispersed. In vitro studies conducted in breast cancer cells (4T1) showed that liposome improved phototoxicity compared to the ClAlPc solution. ClAlPc-loaded liposomes also enhanced the production of ROS 3-fold compared to the ClAlPc solution. Finally, confocal microscopy and flow cytometry demonstrated the ability of the liposomes to enter cells and deliver the fluorescent ClAlPc photosensitizer with dose and time-dependent effects. Thus, this work showed that Box-Behnken factorial design was an effective strategy for optimizing formulation development. The obtained ClAlPc liposomes can be applied for photodynamic therapy in breast cancer cells.
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Pancreatic leaks occur when a disruption in the pancreatic ductal system results in the leakage of pancreatic enzymes such as amylase, lipase, and proteases into the abdominal cavity. While often associated with pancreatic surgical procedures, trauma and necrotizing pancreatitis are also common culprits. Cross-sectional imaging, particularly computed tomography, plays a crucial role in assessing postoperative conditions and identifying both early and late complications, including pancreatic leaks. The presence of fluid accumulation or hemorrhage near an anastomotic site strongly indicates a pancreatic fistula, particularly if the fluid is connected to the pancreatic duct or anastomotic suture line. Pancreatic fistulas are a type of pancreatic leak that carries a high morbidity rate. Early diagnosis and assessment of pancreatic leaks require vigilance and an understanding of its imaging hallmarks to facilitate prompt treatment and improve patient outcomes. Radiologists must maintain vigilance and understand the imaging patterns of pancreatic leaks to enhance diagnostic accuracy. Ongoing improvements in surgical techniques and diagnostic approaches are promising for minimizing the prevalence and adverse effects of pancreatic fistulas. In this pictorial review, our aim is to facilitate for radiologists the comprehension of pancreatic leaks and their essential imaging patterns.