90 research outputs found
High-flow nasal oxygen versus conventional oxygen therapy and noninvasive ventilation in COVID-19 respiratory failure: a systematic review and network meta-analysis of randomised controlled trials
Background:
Noninvasive methods of respiratory support, including noninvasive ventilation (NIV), continuous positive airway pressure (CPAP), and high-flow nasal oxygen (HFNO), are potential strategies to prevent progression to requirement for invasive mechanical ventilation in acute hypoxaemic respiratory failure. The COVID-19 pandemic provided an opportunity to understand the utility of noninvasive respiratory support among a homogeneous cohort of patients with contemporary management of acute respiratory distress syndrome. We performed a network meta-analysis of studies evaluating the efficacy of NIV (including CPAP) and HFNO, compared with conventional oxygen therapy (COT), in patients with COVID-19.
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Methods:
PubMed, Embase, and the Cochrane library were searched in May 2023. Standard random-effects meta-analysis was used first to estimate all direct pairwise associations and the results from all studies were combined using frequentist network meta-analysis. Primary outcome was treatment failure, defined as discontinuation of HFNO, NIV, or COT despite progressive disease. Secondary outcome was mortality.
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Results:
We included data from eight RCTs with 2302 patients, (756 [33%] assigned to COT, 371 [16%] to NIV, and 1175 [51%] to HFNO). The odds of treatment failure were similar for NIV (P=0.33) and HFNO (P=0.25), and both were similar to that for COT (reference category). The odds of mortality were similar for all three treatments (odds ratio for NIV vs COT: 1.06 [0.46–2.44] and HFNO vs COT: 0.97 [0.57–1.65]).
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Conclusions:
Noninvasive ventilation, high-flow nasal oxygen, and conventional oxygen therapy are comparable with regards to treatment failure and mortality in COVID-19-associated acute respiratory failure.
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Prospero registration:
CRD42023426495
Prediction of Complications and Prognostication in Perioperative Medicine: A Systematic Review and PROBAST Assessment of Machine Learning Tools
Background:
The utilization of artificial intelligence and machine learning as diagnostic and predictive tools in perioperative medicine holds great promise. Indeed, many studies have been performed in recent years to explore the potential. The purpose of this systematic review is to assess the current state of machine learning in perioperative medicine, its utility in prediction of complications and prognostication, and limitations related to bias and validation.
Methods:
A multidisciplinary team of clinicians and engineers conducted a systematic review using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocol. Multiple databases were searched, including Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Cochrane Library, PubMed, Medline, Embase, and Web of Science. The systematic review focused on study design, type of machine learning model used, validation techniques applied, and reported model performance on prediction of complications and prognostication. This review further classified outcomes and machine learning applications using an ad hoc classification system. The Prediction model Risk Of Bias Assessment Tool (PROBAST) was used to assess risk of bias and applicability of the studies.
Results:
A total of 103 studies were identified. The models reported in the literature were primarily based on single-center validations (75%), with only 13% being externally validated across multiple centers. Most of the mortality models demonstrated a limited ability to discriminate and classify effectively. The PROBAST assessment indicated a high risk of systematic errors in predicted outcomes and artificial intelligence or machine learning applications.
Conclusions:
The findings indicate that the development of this field is still in its early stages. This systematic review indicates that application of machine learning in perioperative medicine is still at an early stage. While many studies suggest potential utility, several key challenges must be first overcome before their introduction into clinical practice
Breast cancer cells treated with proton beam: Immunological features and gene signatures
The breast cancer (BC) disease is characterized by a wide heterogeneity at both clinical and molecular level, showing distinct subtypes with different clinical outcomes. Thus, the choice of the therapeutic plan, such as the type of radiotherapy (RT) need to take into account this complexity. Indeed, the proton therapy (PT) shows a medical benefit compared to conventional X-ray RT, as regards the localized delivery of the radiation dose sparing health tissues, but few data regarding proton-induced molecular changes are currently available. The aim of this study was therefore to investigate the production of immunological molecules and gene expression profiles induced by proton irradiation on BC cell lines. Clonogenic survival assay, luminex assay and cDNA microarray gene expression analyses were performed both in the non-tumorigenic MCF10A cell line and in two tumorigenic MCF7 and MDA-MB-231 cell lines, following irradiation with 0.5, 2 and 9 Gy of clinical proton beams. We found that proton irradiation induced gene expression changes useful to define a cell line and dose-dependent gene signatures. The lack of molecular data in the literature can be filled by data here presented that could represent a useful tool to better understand the molecular mechanisms elicited by protons predicting the treatment outcome
Evaluation of Proton-Induced Biomolecular Changes in MCF-10A Breast Cells by Means of FT-IR Microspectroscopy
Radiotherapy (RT) with accelerated beams of charged particles (protons and carbon ions),
also known as hadrontherapy, is a treatment modality that is increasingly being adopted thanks to the
several benefits that it grants compared to conventional radiotherapy (CRT) treatments performed
by means of high-energy photons/electrons. Hence, information about the biomolecular effects in
exposed cells caused by such particles is needed to better realize the underlying radiobiological
mechanisms and to improve this therapeutic strategy. To this end, Fourier transform infrared
microspectroscopy (-FT-IR) can be usefully employed, in addition to long-established radiobiological
techniques, since it is currently considered a helpful tool for examining radiation-induced cellular
changes. In the present study, MCF-10A breast cells were chosen to evaluate the effects of proton
exposure using -FT-IR. They were exposed to different proton doses and fixed at various times
after exposure to evaluate direct effects due to proton exposure and the kinetics of DNA damage
repair. Irradiated and control cells were examined in transflection mode using low-e substrates that
have been recently demonstrated to offer a fast and direct way to examine proton-exposed cells. The
acquired spectra were analyzed using a deconvolution procedure and a ratiometric approach, both of
which showed the different contributions of DNA, protein, lipid, and carbohydrate cell components.
These changes were particularly significant for cells fixed 48 and 72 h after exposure. Lipid changes
were related to variations in membrane fluidity, and evidence of DNA damage was highlighted.
The analysis of the Amide III band also indicated changes that could be related to different enzyme
contributions in DNA repair
Early Monitoring Response to Therapy in Patients with Brain Lesions Using the Cumulative SUV Histogram
Featured Application The study proposes a methodology to evaluate the response of patients with brain lesions to Gamma Knife treatments through the use of Positron Emission Tomography imaging. Gamma Knife treatment is an alternative to traditional brain surgery and whole-brain radiation therapy for treating cancers that are inaccessible via conventional treatments. To assess the effectiveness of Gamma Knife treatments, functional imaging can play a crucial role. The aim of this study is to evaluate new prognostic indices to perform an early assessment of treatment response to therapy using positron emission tomography imaging. The parameters currently used in nuclear medicine assessments can be affected by statistical fluctuation errors and/or cannot provide information on tumor extension and heterogeneity. To overcome these limitations, the Cumulative standardized uptake value (SUV) Histogram (CSH) and Area Under the Curve (AUC) indices were evaluated to obtain additional information on treatment response. For this purpose, the absolute level of [11C]-Methionine (MET) uptake was measured and its heterogeneity distribution within lesions was evaluated by calculating the CSH and AUC indices. CSH and AUC parameters show good agreement with patient outcomes after Gamma Knife treatments. Furthermore, no relevant correlations were found between CSH and AUC indices and those usually used in the nuclear medicine environment. CSH and AUC indices could be a useful tool for assessing patient responses to therapy
FT-IR Transflection Micro-Spectroscopy Study on Normal Human Breast Cells after Exposure to a Proton Beam
Fourier transform infrared micro-spectroscopy (mu-FT-IR) is nowadays considered a valuable tool for investigating the changes occurring in human cells after exposure to ionizing radiation. Recently, considerable attention has been devoted to the use of this optical technique in the study of cells exposed to proton beams, that are being increasingly adopted in cancer therapy. Different experimental configurations are used for proton irradiation and subsequent spectra acquisition. To facilitate the use of mu-FT-IR, it may be useful to investigate new experimental approaches capable of speeding up and simplifying the irradiation and measurements phases. Here, we propose the use of low-e-substrates slides for cell culture, allowing the irradiation and spectra acquisition in transflection mode in a fast and direct way. In recent years, there has been a wide debate about the validity of these supports, but many researchers agree that the artifacts due to the presence of the electromagnetic standing wave effects are negligible in many practical cases. We investigated human normal breast cells (MCF-10 cell line) fixed immediately after the irradiation with graded proton radiation doses (0, 0.5, 2, and 4 Gy). The spectra obtained in transflection geometry showed characteristics very similar to those present in the spectra acquired in transmission geometry and confirm the validity of the chosen approach. The analysis of spectra indicates the occurrence of significant changes in DNA and lipids components of cells. Modifications in protein secondary structure are also evidenced
Transcriptional modulations induced by proton irradiation in mice skin in function of adsorbed dose and distance
Hadron therapy by proton beams represents an advanced anti-cancer strategy due to its highly localized dose deposition allowing a greater sparing of normal tissue and/or organs at risk compared to photon/electron radiotherapy. However, it is not clear to what extent non-targeted effects such as transcriptional modulations produced along the beamline may diffuse and impact the surrounding tissue. In this work, we analyze the transcriptome of proton-irradiated mouse skin and choose two biomarker genes to trace their modulation at different distances from the beam's target and at different doses and times from irradiation to understand to what extent and how far it may propagate, using RNA-Seq and quantitative RT-PCR. In parallel, assessment of lipids alteration is performed by FTIR spectroscopy as a measure of tissue damage. Despite the observed high individual variability of expression, we can show evidence of transcriptional modulation of two biomarker genes at considerable distance from the beam's target where a simulation system predicts a significantly lower adsorbed dose. The results are compatible with a model involving diffusion of transcripts or regulatory molecules from high dose irradiated cells to distant tissue's portions adsorbing a much lower fraction of radiation
Proton-irradiated breast cells: molecular points of view
Breast cancer (BC) is the most common cancer in women, highly heterogeneous at both the clinical and molecular level. Radiation therapy (RT) represents an efficient modality to treat localized tumor in BC care, although the choice of a unique treatment plan for all BC patients, including RT, may not be the best option. Technological advances in RT are evolving with the use of charged particle beams (i.e. protons) which, due to a more localized delivery of the radiation dose, reduce the dose administered to the heart compared with conventional RT. However, few data regarding proton-induced molecular changes are currently available. The aim of this study was to investigate and describe the production of immunological molecules and gene expression profiles induced by proton irradiation. We performed Luminex assay and cDNA microarray analyses to study the biological processes activated following irradiation with proton beams, both in the non-tumorigenic MCF10A cell line and in two tumorigenic BC cell lines, MCF7 and MDA-MB-231. The immunological signatures were dose dependent in MCF10A and MCF7 cell lines, whereas MDA-MB-231 cells show a strong pro-inflammatory profile regardless of the dose delivered. Clonogenic assay revealed different surviving fractions according to the breast cell lines analyzed. We found the involvement of genes related to cell response to proton irradiation and reported specific cell line- and dose-dependent gene signatures, able to drive cell fate after radiation exposure. Our data could represent a useful tool to better understand the molecular mechanisms elicited by proton irradiation and to predict treatment outcome
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