Photodynamic therapy for colorectal cancer: an update and a look to the future

This review provides an update on the current state of photodynamic therapy (PDT) for colorectal cancer (CRC) and explores potential future directions in this field. PDT has emerged as a promising minimally invasive treatment modality that utilizes photosensitizers and specific light wavelengths to induce cell death in targeted tumor tissues. In recent years, significant progress has been made in understanding the underlying mechanisms, optimizing treatment protocols, and improving the efficacy of PDT for CRC. This article highlights key advancements in PDT techniques, including novel photosensitizers, light sources, and delivery methods. Furthermore, it discusses ongoing research efforts and potential future directions, such as combination therapies and nanotechnology-based approaches. By elucidating the current landscape and providing insights into future directions, this review aims to guide researchers and clinicians in harnessing the full potential of PDT for the effective management of CRC.(PTDC/FIS-OTI/1259/2020

Assessing the Effect on Outcomes of Public or Private Provision of Prenatal Care in Portugal

To evaluate whether public and private prenatal care users experience similar outcomes, taking into consideration maternal pre-pregnancy social and clinical risk. We studied 7,325 women who delivered single newborns at five public maternity units in Porto, Portugal. Health behaviors and prenatal care were self-reported; pregnancy complications and delivery data were retrieved from medical files. The odds of inadequate weight gain, continuing to smoke, gestational hypertension, gestational diabetes, caesarean section, preterm birth, low birthweight, and small- and large-for-gestational-age were estimated for public and private providers using logistic regression, stratified by pre-pregnancy risk profile, adjusted for maternal characteristics. 38 % of women used private prenatal care. Among low-risk women, public care users were more likely to gain excessive weight (OR 1.26; 95 % CI 1.06–1.57) and be diagnosed with gestational diabetes (OR 1.37; 95 % CI 1.01–1.86). They were less likely to have a caesarean (OR 0.63; 95 % CI 0.51–0.78) and more likely to deliver small-for-gestational-age babies (OR 1.48; 95 % CI 1.19–1.83). Outcomes were similar in high-risk women although preterm and pre-labor caesarean were less frequent in public care users (OR 0.64 95 % CI 0.45–0.91; OR 0.69 95 % CI 0.49–0.97). The amount of care was not significantly related to risk profile in either case. Public care users experienced similar outcomes to those using private care, despite higher pre-pregnancy disadvantage. Low-risk women need further attention if narrowing inequalities in birth outcomes remains a priority

Non-contact optical analysis of the viscoelastic properties for food quality using Brillouin spectroscopy

Brillouin spectroscopy probes the viscoelastic properties of materials by observing the scattered light spectrum from a laser source incident on a given sample. The peak contained in the Brillouin scattering region of the spectrum can be directly correlated to the storage and loss modulus, providing a complex analysis of the physical properties of the study subject (Figure1a) [1]. For the food industry, where the traditional and contact-based rheological measurement techniques dominate the characterization of the physical characteristics of products from raw material to finished foods, Brillouin spectroscopy brings a new and relevant noncontact alternative [2]. Also, this technique is useful for measurement of products inside of sealed packages, allowing the characterization of samples through a transparent window without any violation of the package. In this study, we explored the potential of the Brillouin spectroscopy to infer changes in viscoelastic properties that occur in different food products when submitted to heating and cooling cycles, freezing and unfreezing cycles, and normal time-based decay [3]. The data was acquired using the setup described in Figure 1b. Significant changes were already observed in the viscoelastic properties of cow’s milk after every day of room temperature and fridge storage, and in cooking oil after consecutive cooling and heating cycles (170 ºC). We also obtained spectrums for meat and fish after every day of fridge storage and after freezing and unfreezing cycles. For non-uniform samples, the acquisition location affects the peak obtained, so different approaches to the acquisition method are still being investigated. These results hint at a future in which we can check if a product was handled with care and transported under the right conditions, if the frozen products have only been frozen once or if meat and fish are really fresh and safe to consume, without ever opening a package or touching/handling the product. This will increase consumer safety and confidence and provide the industry with the necessary tools to ensure and improve the quality of their products without waste.This work was supported by FCT with the project MPhotonBiopsy, PTDC/FIS-OTI/1259/2020. B. Esteves thanks to FCT for the Ph.D. grant with the reference 2021.07239.BD

Enhanced photodynamic therapy: a review of combined energy sources

Photodynamic therapy (PDT) has been used in recent years as a non-invasive treatment for cancer, due to the side effects of traditional treatments such as surgery, radiotherapy, and chemother apy. This therapeutic technique requires a photosensitizer, light energy, and oxygen to produce reactive oxygen species (ROS) which mediate cellular toxicity. PDT is a useful non-invasive therapy for cancer treatment, but it has some limitations that need to be overcome, such as low-light-penetration depths, non-targeting photosensitizers, and tumor hypoxia. This review focuses on the latest innovative strategies based on the synergistic use of other energy sources, such as non-visible radiation of the electromagnetic spectrum (microwaves, infrared, and X-rays), ultrasound, and electric/magnetic fields, to overcome PDT limitations and enhance the therapeutic effect of PDT. The main principles, mechanisms, and crucial elements of PDT are also addressedThis work was supported by project MME reference 105399; CMEMS-UMinho Strategic Project UIDB/04436/2020 and UIDP/04436/2020; Infrastructures Micro&NanoFabs@PT, NORTE-01-0145-FEDER-022090, Portugal 2020; and MPhotonBiopsy, PTDC/FIS-OTI/1259/202

Photodynamic therapy review: principles, photosensitizers, applications, and future directions

Photodynamic therapy (PDT) is a minimally invasive therapeutic modality that has gained great attention in the past years as a new therapy for cancer treatment. PDT uses photosensitizers that, after being excited by light at a specific wavelength, react with the molecular oxygen to create reactive oxygen species in the target tissue, resulting in cell death. Compared to conventional therapeutic modalities, PDT presents greater selectivity against tumor cells, due to the use of photosensitizers that are preferably localized in tumor lesions, and the precise light irradiation of these lesions. This paper presents a review of the principles, mechanisms, photosensitizers, and current applications of PDT. Moreover, the future path on the research of new photosensitizers with enhanced tumor selectivity, featuring the improvement of PDT effectiveness, has also been addressed. Finally, new applications of PDT have been covered.This work was supported by FCT with project OpticalBrain reference PTDC/CTMREF/28406/2017, operation code POCI-01-0145-FEDER-028406, through the COMPETE 2020; CMEMSUMinho Strategic Project UIDB/04436/2020; Infrastructures Micro&NanoFabs@PT, operation code NORTE 01-0145-FEDER-022090, POR Norte, Portugal 2020; and MPhotonBiopsy, PTDC/FIS-OTI/1259/2020. The authors thank Biolitec research GmbH (Jena, Germany) for providing the photosensitizer Foscan®.The APC was funded by Chongqing Technology and Business University (CTBU)

Critical evaluation of national vital statistics: the case of preterm birth trends in Portugal

INTRODUCTION: Using vital statistics, the Portuguese National Health Plan predicts that 14% of live births will be preterm in 2016. The prediction was based on a preterm birth rise from 5.9% in 2000 to 8.8% in 2009. However, the same source showed an actual decline from 2010 onwards. To assess the plausibility of national preterm birth trends, we aimed to compare the evolution of preterm birth and low birthweight rates between vital statistics and a hospital database. MATERIAL AND METHODS: A time-trend analysis (2004-2011) of preterm birth (<37 gestational weeks) and low birthweight (<2500 g) rates was conducted using data on singleton births from the national birth certificates (n = 801,783) and an electronic maternity unit database (n = 21,392). Annual prevalence estimates, ratios of preterm birth:low birthweight and adjusted prevalence ratios were estimated to compare data sources. RESULTS: Although the national prevalence of preterm birth increased from 2004 (5.4%), particularly between 2006 and 2009 (highest rate was 7.5% in 2007), and decreased after 2009 (5.7% in 2011), the prevalence at the maternity unit remained constant. Between 2006 and 2009, preterm birth was almost 1.4 times higher in the national statistics (using the national or the catchment region samples) than in the maternity unit, but no differences were found for low birthweight. CONCLUSION: Portuguese preterm birth prevalence seems biased between 2006 and 2009, suggesting that early term babies were misclassified as preterm. As civil registration systems are important to support public health decisions, monitoring strategies should be taken to assure good quality data

Silicon nitride thin-films deposited by radiofrequency reactive sputtering: refractive index optimization with substrate cooling in a nitrogen-rich atmosphere

Silicon nitride (SiN) is widely used as a core material in optical waveguides due to its optical properties. The deposition of SiN thin-films by radiofrequency (RF) reactive sputtering is commonly used in low-temperature processes, where the thin-films optical properties can be optimized by controlling the deposition parameters (sputtering power, gases ratio, etc.). This work presents the deposition of several SiN thin-films by RF reactive sputtering with different sputtering powers (ranging from 180 W to 300 W), with a nitrogen-argon ratio of 16:4, and performing substrate cooling in a nitrogen-rich atmosphere immediately after deposition, consisting in keeping the substrate under 16 sccm of nitrogen until it reaches 25 ◦C. The refractive indices of the SiN thin-films were assessed through ellipsometry, obtaining a maximum refractive index of 1.906 at 400 nm. SiN thin-films were also analyzed by energy-dispersive spectroscopy (EDS) and atomic force microscopy (AFM).This work is supported by: MPhotonBiopsy, PTDC/FISOTI/1259/2020, http://doi.org/10.54499/PTDC/FIS-OTI/1259/2020; and CMEMS-UMinho Strategic Project UIDB/04436/2020 and UIDP/ 04436/2020. João R. Freitas thanks FCT (Fundação para a Ciência e a Tecnologia) for the Ph.D. grant, 2020.07708.BD. Sara Pimenta thanks FCT for the grant 2022.00101.CEECIND/CP1718/CT0008, https://doi.org/10.54499/2022.00101.CEECIND/CP1718/CT0008

Pectus Excavatum postsurgical outcome based on preoperative soft body dynamics simulation

Pectus excavatum is the most common congenital deformity of the anterior chest wall, in which an abnormal formation of the rib cage gives the chest a caved-in or sunken appearance. Today, the surgical correction of this deformity is carried out in children and adults through Nuss technic, which consists in the placement of a prosthetic bar under the sternum and over the ribs. Alth ough this technique has been shown to be safe and reliable, not all patients have achieved adequate cosmetic outcome. This often leads to psyc hological problems and social stress, before and after the surgical correction. This paper targets this particular problem by presenting a method to predict the patient surgical outcome based on pre-surgical imagiologic information and chest skin dynamic modulation. The proposed approach uses the patient pre-surgical thoracic CT scan and anatomical-surg ical references to perform a 3D segmentation of the left ribs, right ribs, sternum and skin. The technique encompasses three steps: a) approximation of the cartilages, between the ribs and the sternum, trough b-spline interpolation; b) a volu metric mass spring model that connects two layers - inner skin layer based on the outer pleura contour and the outer su rface skin; and c) displacement of the sternum according to the prosthetic bar position. A dynamic model of the skin around the chest wall region was generated, capable of simulating the effect of the movement of the prosthetic bar along the sternum. The results were compared and validated with patient postsurgical skin surface acquired with Polhemus FastSCAN system.Fundação para a Ciência e Tecnologi