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1.
Neural Regen Res ; 20(4): 1031-1041, 2025 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38845231

RESUMO

Astrocytes are the most abundant type of glial cell in the central nervous system. Upon injury and inflammation, astrocytes become reactive and undergo morphological and functional changes. Depending on their phenotypic classification as A1 or A2, reactive astrocytes contribute to both neurotoxic and neuroprotective responses, respectively. However, this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries. Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles, which emphasizes the heterogeneous nature of their reactivity. Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types, releasing cytokines, and influencing the immune response. The phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior, as evidenced by in silico , in vitro , and in vivo results. In astrocytes, inflammatory cues trigger a cascade of molecular events, where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses. Here, we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation. We highlight the involvement of various signaling pathways that regulate astrocyte reactivity, including the PI3K/AKT/mammalian target of rapamycin (mTOR), α v ß 3 integrin/PI3K/AKT/connexin 43, and Notch/PI3K/AKT pathways. While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage, evidence suggests that activating this pathway could also yield beneficial outcomes. This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation. The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior. The findings should then be validated using in vivo models to ensure real-life relevance. The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage, although further studies are required to fully comprehend its role due to varying factors such as different cell types, astrocyte responses to inflammation, and disease contexts. Specific strategies are clearly necessary to address these variables effectively.

2.
Obes Surg ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001982

RESUMO

INTRODUCTION: Metabolic and bariatric surgery (MBS) has experienced considerable growth, addressing the challenges of obesity and its complications. The lack of a comprehensive bibliometric analysis in Latin America motivates this study, highlighting the need to understand the evolution of research in this area and its impact on clinical decision-making and health policies. METHODOLOGY: A cross-sectional bibliometric study was carried out using the Scopus database. A structured search strategy was designed to identify articles related to bariatric surgery with authors affiliated with Latin American countries. Inclusion and exclusion criteria were applied, followed by a descriptive and bibliometric analysis of the scientific production found. RESULTS: A total of 3553 documents published between 1991 and 2024 were included. There was an annual growth of 11%, with an average age of documents of 7.5 years. A concentration was observed in some countries, notably Brazil, Mexico, and Chile. Although scientific output increased, the average number of citations per article showed a downward trend since 2003. DISCUSSION: Despite the growth in scientific production, the quality and relevance of research is questioned, especially given the decrease in the impact received. It highlights the lack of meaningful regional collaboration, which could limit the sharing of knowledge and resources. Questions are raised about gaps in research capacity and the economic and development implications are discussed. CONCLUSIONS: This study provides valuable information to strengthen future research in bariatric surgery in Latin America. It highlights the importance of promoting regional and international collaboration and improving research training in countries with less participation. Clinical intervention strategies can benefit from better understanding research trends and adopting evidence-based practices in a more informed manner.

3.
Cureus ; 16(6): e62149, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38993411

RESUMO

Spontaneous spinal epidural hematoma (SSEH) represents a rare clinical entity with an indeterminate etiology. Timely diagnosis and intervention are imperative due to the significant risk of permanent neurological deficits in the absence of appropriate treatment. This case report presents an instance of SSEH with no clear etiology. The patient arrived at the emergency department with paraplegia, urinary and fecal incontinence, and loss of pain and temperature sensation. She reported that these symptoms began abruptly after sneezing. The patient denied any pertinent medical history or family history. The patient initially experienced epigastric pain, which progressed to paresthesia. Magnetic resonance imaging confirmed an epidural hematoma extending from T2 to T8, necessitating immediate neurosurgical intervention. Although the patient was expected to recover within 72 hours postoperation, her symptoms persisted. Based on her clinical presentation, a diagnosis of anterior cord syndrome secondary to SSEH was confirmed.

4.
PNAS Nexus ; 3(7): pgae239, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38966011

RESUMO

Patients are reluctant to use telemedicine health services, compared to its substitute in-person visits. One reason is that telemedicine can be accurately evaluated and compared to its substitute only after the product has been adopted and experienced. As such, an intervention that increases the probability of a first experience can have lasting effects. This article reports the results of a randomized field experiment conducted in collaboration with a health insurance company. During the intervention, half of the households out of 3,469 in the sample received periodic e-mails with information about the available services. It effectively increased the take-up and demand for telemedicine. Within the first 8 months of the experiment, patients assigned to the treatment group were 6 percentage points more likely to have used the service at least once (and had about five times the odds of using telemedicine compared to those in the control group). Eight months after the start of the intervention, the number of virtual consultations by the treatment group was six times larger than that of the control group. These results, even if limited by the sample and context in which the intervention took place, provide additional evidence about how information interventions can increase technological take-up within the health sector and could serve as the stepping stone for evaluating the impact of telemedicine on health outcomes causally.

5.
J Clin Exp Dent ; 16(5): e595-e601, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38988753

RESUMO

Background: Intracanal medication is considered an alternative after instrumentation in the case of pulp necrosis. However, the elimination of this medication plays an important role in the obturation process, which is why various chelating solutions have currently been studied for this purpose. Therefore, this study aimed to analyze the irrigant based on alendronic acid (AA), which contains in its chemical structure functional groups capable of forming complexes with Ca2+ ions. Material and Methods: 90 single-rooted teeth were crowned and standardized to a length of 13 mm. They were instrumented with a progressive K file (Dentsply Maillefer) from #15 to #30. Ca(OH)2 was placed as intracanal medication for 7 days. The roots were randomly divided into the following 4 experimental groups (n=13) according to the irrigant used: 2.25% NaClO, calcium suspension, 0.22% AA, and 10% citric acid; as well as negative (n=5; saline solution) and positive controls (n=5, 17% EDTA). The roots were divided longitudinally and the % of permeable dentinal tubules (% PDT) was determined by thirds (cervical, middle and apical), by analyzing the micrographs obtained by scanning electron microscope (SEM) and the imageJ program. The quantification of the remaining Ca2+ was determined using the Arsenazo III technique. Results: The Kruskal Wallis test was used for the % of permeable dentinal tubules where a significant difference was determined for the different thirds (p<0.005). In the apical third, citric acid and AA irrigants presented a median of 17.71 and 17.51 % PDT respectively. In relation to the quantification of the remaining total calcium, the lowest value was found with AA with a concentration of 4.83 mmol/L. Conclusions: The 0.22% AA solution has the same capacity to remove Ca(OH)2 from the root canal walls as 17% EDTA and 10% citric acid. Key words:Alendronic acid, calcium hydroxide, citric acid, EDTA, irrigant solution,root canal.

6.
Methods Mol Biol ; 2816: 139-144, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38977595

RESUMO

Phosphatidic acid (PA) is a key signaling lipid that plays a crucial role in regulating various cellular processes. Studies have shown that azobenzene-containing PA analogues can be used as an all-chemical strategy for light-mediated control of PA signaling. These photoswitchable lipids offer a solution to the limitations of traditional bulk dosing methods by allowing for light- and shape-dependent interactions with protein effectors and lipid-metabolizing enzymes. This chapter describes how to synthesize AzoPA and dAzoPA.


Assuntos
Compostos Azo , Ácidos Fosfatídicos , Transdução de Sinais , Ácidos Fosfatídicos/metabolismo , Ácidos Fosfatídicos/química , Compostos Azo/química , Humanos
7.
Methods Mol Biol ; 2816: 193-204, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38977600

RESUMO

With impaired retinal ganglion cell (RGC) function and eventual RGC death, there is a heightened risk of experiencing glaucoma-induced blindness or other optic neuropathies. Poor RGC efficiency leads to limited transmission of visual signals between the retina and the brain by RGC axons. Increased focus on studying lipid messengers found in neurons such as endocannabinoids (eCBs) has importance due to their potential axonal pathway regenerative properties. 2-Arachidonoylglycerol (2-AG), a common eCB, is synthesized from an sn-1 hydrolysis reaction between diacylglycerol (DAG) and diacylglycerol lipase (DAGL). Examination of DAG production allows for future downstream analysis in relation to DAGL functionality. Here, we describe protocol guidelines for extracting RGCs from mouse retinas and subsequent mass spectrometry analysis of the DAG content present within the RGCs.


Assuntos
Diglicerídeos , Células Ganglionares da Retina , Transdução de Sinais , Células Ganglionares da Retina/metabolismo , Animais , Camundongos , Diglicerídeos/metabolismo , Endocanabinoides/metabolismo , Glicerídeos/metabolismo , Lipase Lipoproteica/metabolismo , Ácidos Araquidônicos/metabolismo , Espectrometria de Massas/métodos , Retina/metabolismo
8.
Methods Mol Biol ; 2816: 175-191, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38977599

RESUMO

The trabecular meshwork (TM) from primary open-angle glaucoma (POAG) cases has been found to contain decreased levels of intracellular plasmalogens. Plasmalogens are a subset of lipids involved in diverse cellular processes such as intracellular signaling, membrane asymmetry, and protein regulation. Proper plasmalogen biosynthesis is regulated by rate-limiting enzyme fatty acyl-CoA reductase (Far1). ATPase phospholipid transporting 8B2 (ATP8B2) is a type IV P-type ATPase responsible for the asymmetric distribution of plasmalogens between the intracellular and extracellular leaflets of the plasma membranes. Here we describe the methodology for extraction and culturing of TM cells from corneal tissue and subsequent downregulation of ATP8B2 using siRNA transfection. Further quantification and downstream effects of ATP8B2 gene knockdown will be analyzed utilizing immunoblotting techniques.


Assuntos
Glaucoma de Ângulo Aberto , Plasmalogênios , Malha Trabecular , Malha Trabecular/metabolismo , Malha Trabecular/citologia , Humanos , Plasmalogênios/metabolismo , Glaucoma de Ângulo Aberto/metabolismo , Glaucoma de Ângulo Aberto/genética , Glaucoma de Ângulo Aberto/patologia , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/genética , RNA Interferente Pequeno/genética , Regulação para Baixo , Células Cultivadas , Técnicas de Silenciamento de Genes
9.
Artigo em Francês | MEDLINE | ID: mdl-38997090

RESUMO

OBJECTIVE: Breast cancer is the leading cancer in women in terms of incidence and mortality. The literature currently identifies several risk factors, some modifiable and others not. Because of its multifactorial nature, the combination of factors either increases or reduces the risk of cancer. Since 2004, the first commission's rapport of the French National Environmental Health Plan has recognized the significant impact of occupational exposure on the development of breast cancer. However, neither primary nor secondary preventive measures have yet been implemented in work environment. METHOD: Based on available literature, we reviewed current knowledge of breast cancer risk factors associated with occupational exposure. RESULTS: The risk factors identified were ionizing radiation, magnetic fields, certain endocrine disruptors, ethylene oxide and night shift work. CONCLUSION: Recognition of breast cancer as an occupational disease is complicated. In some cases, however, it may be possible, particularly in cases of multifactorial exposure. This work should help to raise awareness among employers and reinforce preventive measures in the workplace.

11.
Eur Spine J ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38987513

RESUMO

BACKGROUND: Clinical prediction models (CPM), such as the SCOAP-CERTAIN tool, can be utilized to enhance decision-making for lumbar spinal fusion surgery by providing quantitative estimates of outcomes, aiding surgeons in assessing potential benefits and risks for each individual patient. External validation is crucial in CPM to assess generalizability beyond the initial dataset. This ensures performance in diverse populations, reliability and real-world applicability of the results. Therefore, we externally validated the tool for predictability of improvement in oswestry disability index (ODI), back and leg pain (BP, LP). METHODS: Prospective and retrospective data from multicenter registry was obtained. As outcome measure minimum clinically important change was chosen for ODI with ≥ 15-point and ≥ 2-point reduction for numeric rating scales (NRS) for BP and LP 12 months after lumbar fusion for degenerative disease. We externally validate this tool by calculating discrimination and calibration metrics such as intercept, slope, Brier Score, expected/observed ratio, Hosmer-Lemeshow (HL), AUC, sensitivity and specificity. RESULTS: We included 1115 patients, average age 60.8 ± 12.5 years. For 12-month ODI, area-under-the-curve (AUC) was 0.70, the calibration intercept and slope were 1.01 and 0.84, respectively. For NRS BP, AUC was 0.72, with calibration intercept of 0.97 and slope of 0.87. For NRS LP, AUC was 0.70, with calibration intercept of 0.04 and slope of 0.72. Sensitivity ranged from 0.63 to 0.96, while specificity ranged from 0.15 to 0.68. Lack of fit was found for all three models based on HL testing. CONCLUSIONS: Utilizing data from a multinational registry, we externally validate the SCOAP-CERTAIN prediction tool. The model demonstrated fair discrimination and calibration of predicted probabilities, necessitating caution in applying it in clinical practice. We suggest that future CPMs focus on predicting longer-term prognosis for this patient population, emphasizing the significance of robust calibration and thorough reporting.

12.
Nutrition ; 125: 112505, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38981374

RESUMO

OBJECTIVES: Given the innovative nature of the method, our study aimed to assess the prognostic significance of body mass index (BMI)-adjusted calf circumference (CC) in older patients who are hospitalized. METHODS: This was a unique analysis as part of other cohorts comprising general hospitalized patients aged 60 years or older of both sexes. Only patients with excess weight (BMI ≥ 25 kg/m2) were included. CC was adjusted by reducing 3, 7, or 12 cm for BMI (in kg/m2) within 25-29.9, 30-39.9, and ≥40 kg/m2, respectively. CC was considered low if ≤ 34 cm for males and ≤ 33 cm for females. Clinical outcomes included prolonged length of hospital stay (LOS) and mortality. RESULTS: A total of 222 patients were included. After BMI adjustments, 72.1% of the patients were reclassified from a normal CC category to a low CC category. The frequency of low CC increased from 33.8% to 81.9% following BMI adjustments. Among those reclassified to the low CC, 11 died, compared to only 2 patients in the group that maintained a normal CC classification. BMI-adjusted CC was inversely associated with mortality (HR adjusted 0.84, 95% CI 0.73 to 0.95), but not with prolonged LOS. CONCLUSIONS: Our novel study highlights the prognostic value of BMI-adjusted CC. As an anthropometric marker of muscle mass, it proved to be a predictor of mortality in older patients with high BMI. This adjustment is further important because it may help to better detect low muscle mass in these patients where such conditions might be masked.

13.
Front Immunol ; 15: 1423689, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040115

RESUMO

Purpose: Natural killer (NK) cells are traditionally identified by flow cytometry using a combination of markers (CD16/CD56/CD3), because a specific NK-cell marker is still missing. Here we investigated the utility of CD314, CD335 and NKp80, compared to CD16/CD56/CD3, for more robust identification of NK-cells in human blood, for diagnostic purposes. Methods: A total of 156 peripheral blood (PB) samples collected from healthy donors (HD) and patients with diseases frequently associated with loss/downregulation of classical NK-cell markers were immunophenotyped following EuroFlow protocols, aimed at comparing the staining profile of total blood NK-cells for CD314, CD335 and NKp80, and the performance of distinct marker combinations for their accurate identification. Results: NKp80 showed a superior performance (vs. CD314 and CD335) for the identification of NK-cells in HD blood. Besides, NKp80 improved the conventional CD16/CD56/CD3-based strategy to identify PB NK-cells in HD and reactive processes, particularly when combined with CD16 for further accurate NK-cell-subsetting. Although NKp80+CD16 improved the identification of clonal/tumor NK-cells, particularly among CD56- cases (53%), aberrant downregulation of NKp80 was observed in 25% of patients, in whom CD56 was useful as a complementary NK-cell marker. As NKp80 is also expressed on T-cells, we noted increased numbers of NKp80+ cytotoxic T-cells at the more advanced maturation stages, mostly in adults. Conclusion: Here we propose a new robust approach for the identification of PB NK-cells, based on the combination of NKp80 plus CD16. However, in chronic lymphoproliferative disorders of NK-cells, addition of CD56 is recommended to identify clonal NK-cells, due to their frequent aberrant NKp80- phenotype.


Assuntos
Imunofenotipagem , Células Matadoras Naturais , Humanos , Células Matadoras Naturais/imunologia , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Neoplasias/imunologia , Neoplasias/diagnóstico , Citometria de Fluxo/métodos , Adulto Jovem , Idoso , Biomarcadores , Adolescente , Proteínas Ligadas por GPI/sangue , Lectinas Tipo C , Receptores de Células Matadoras Naturais , Antígenos B7
14.
Artigo em Inglês | MEDLINE | ID: mdl-38953890

RESUMO

BACKGROUND: This study aimed to evaluate if combining low muscle mass with additional body composition abnormalities, such as myosteatosis or adiposity, could improve survival prediction accuracy in a large cohort of gastrointestinal and genitourinary malignancies. METHODS: In total, 2015 patients with surgically-treated gastrointestinal or genitourinary cancer were retrospectively analyzed. Skeletal muscle index, skeletal muscle radiodensity, and visceral/subcutaneous adipose tissue index were determined. The primary outcome was overall survival determined by hospital records. Multivariate Cox hazard models were used to identify independent predictors for poor survival. C-statistics were assessed to quantify the prognostic capability of the models with or without incorporating body composition parameters. RESULTS: Survival curves were significantly demarcated by all 4 measures. Skeletal muscle radiodensity was associated with non-cancer-related deaths but not with cancer-specific survival. The survival outcome of patients with low skeletal muscle index was poor (5-year OS; 65.2%), especially when present in combination with low skeletal muscle radiodensity (5-year overall survival; 50.2%). All examined body composition parameters were independent predictors of lower overall survival. The model for predicting overall survival without incorporating body composition parameters had a c-index of 0.68 but increased to 0.71 with the inclusion of low skeletal muscle index and 0.72 when incorporating both low skeletal muscle index and low skeletal muscle radiodensity/visceral adipose tissue index/subcutaneous adipose tissue index. CONCLUSION: Patients exhibiting both low skeletal muscle index and other body composition abnormalities, particularly low skeletal muscle radiodensity, had poorer overall survival. Models incorporating multiple body composition prove valuable for mortality prediction in oncology settings.

15.
Brain Inj ; : 1-9, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967329

RESUMO

OBJECTIVE: To estimate rates and time to reach emergence of consciousness from vegetative state/unresponsive wakefulness syndrome (VS/UWS), and explore factors associated with improved recovery in children and adolescents with disorders of consciousness (DoC) following severe traumatic and non-traumatic brain injury. METHODS: Analytical, retrospective, cohort study. Clinical records of consecutively referred patients admitted in VS/UWS to a neurological rehabilitation institute in Argentina, between 2005 and 2021 were reviewed. Seventy children and adolescents were included in the analysis. A specialized 12-week rehabilitation program was administered, and emergence was defined by scores ≥44 points on the Western Neuro Sensory Stimulation Profile (WNSSP), sustained for at least 3 weeks on consecutive weekly evaluations. RESULTS: Emergence from VS/UWS to consciousness occurred within 5.4 (SD 2.6) weeks in almost one-third of patients. Multivariate Cox regression analysis showed emergence was significantly lower in patients with hypoxic ischemic encephalopathy compared to patients with other non-traumatic etiologies [HRadj 0.23 (95% CI 0.06-0.89); p = 0.03)]. CONCLUSIONS: Our findings reinforce growing evidence on the impact of etiology on DoC recovery in pediatric populations, ultimately influencing treatment and family-related decisions in child neurorehabilitation.

17.
Sci Rep ; 14(1): 15741, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977822

RESUMO

Rhythmic entrainment is a fundamental aspect of musical behavior, but the skills required to accurately synchronize movement to the beat seem to develop over many years. Motion capture studies of corporeal synchronization have shown immature abilities to lock in to the beat in children before age 5, and reliable synchronization ability in adults without musical training; yet there is a lack of data on full-body synchronization skills between early childhood and adulthood. To document typical rhythmic synchronization during middle childhood, we used a wireless motion capture device to measure period- and phase-locking of full body movement to rhythm and metronome stimuli in 6 to 11 year-old children in comparison with adult data. Results show a gradual improvement with age; however children's performance did not reach adult levels by age 12, suggesting that these skills continue to develop during adolescence. Our results suggest that in the absence of specific music training, full-body rhythmic entrainment skills improve gradually during middle childhood, and provide metrics for examining the continued maturation of these skills during adolescence.


Assuntos
Música , Humanos , Criança , Masculino , Feminino , Desenvolvimento Infantil/fisiologia , Periodicidade , Adulto , Movimento/fisiologia , Adolescente
18.
Nutrients ; 16(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38999845

RESUMO

BACKGROUND: Childhood overweight and obesity is a global concern and has increased in Spain over the last decades. Combinations of lifestyle behaviors (i.e., diet, sleep, and sedentarism) are highly related to weight status. Therefore, this study aimed to identify lifestyle patterns among children from Madrid City, and analyze associations with the prevalence of overweight, obesity, and abdominal obesity, considering socio-economic factors. METHODS: A cross-sectional analysis was conducted on 4545 children from the ENPIMAD study with data on diet, sleep, anthropometric, and socio-economic variables. K-means cluster analysis was used to identify lifestyle clusters, and logistic regressions were used to examine the associations between socio-economic indicators and cluster membership, and between clusters and weight status. RESULTS: Findings show three lifestyle clusters (healthy, mixed, and unhealthy), with boys and older children more represented in the unhealthy cluster. Food insecurity and low socio-economic status were associated with unhealthier clusters in boys and girls. Children in unhealthier clusters were more likely to have obesity and abdominal obesity. However, these associations disappeared in girls after controlling for food insecurity. CONCLUSION: These results provide insight into the combination of behaviors and socio-economic factors associated with childhood obesity that may aid in the design of future interventions.


Assuntos
Dieta , Estilo de Vida , Obesidade Infantil , Tempo de Tela , Sono , Humanos , Masculino , Feminino , Espanha/epidemiologia , Criança , Obesidade Infantil/epidemiologia , Estudos Transversais , Dieta/estatística & dados numéricos , Fatores Socioeconômicos , Análise por Conglomerados , Peso Corporal , Obesidade Abdominal/epidemiologia , Prevalência , Insegurança Alimentar , Sobrepeso/epidemiologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-39005728

RESUMO

Purpose: Early detection and diagnosis of cancer is critical for achieving positive therapeutic outcomes. Biomarkers that can provide clinicians with clues to the outcome of a given therapeutic course are highly desired. Oxygen is a small molecule that is nearly universally present in biological tissues and plays a critical role in the effectiveness of radiotherapies by reacting with DNA radicals and subsequently impairing cellular repair of double strand breaks.Techniques for measuring oxygen in biological tissues often use blood oxygen saturation to approximate the oxygen partial pressure in surrounding tissues despite the complex, nonlinear, and dynamic relationship between these two separate oxygen populations. Methods and materials: We combined a directly oxygen-sensitive, tumor-targeted, chemical contrast nanoelement with the photoacoustic lifetime-based (PALT) oxygen imaging technique to obtain image maps of oxygen in breast cancer tumors in vivo. The oxygen levels of patient-derived xenografts in a mouse model were characterized before and after a course of radiotherapy. Results: We show that, independent of tumor size, radiotherapy induced an increase in the overall oxygenation levels of the tumor. Further, this increase in the oxygenation of the tumor significantly correlated with a positive response to radiotherapy, as demonstrated by a reduction in tumor volume over the twenty-day monitoring period following therapy and histological staining. Conclusion: Our PALT imaging presented here is simple, fast, and non-invasive. Facilized by the PALT approach, imaging of tumor reoxygenation may be utilized as a simple, early indicator for evaluating cancer response to radiotherapy. Further characterization of the reoxygenation degree, temporal onset, and possible theragnostic implications are warranted.

20.
BMJ Open ; 14(7): e084849, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019641

RESUMO

INTRODUCTION: Oxygen is frequently prescribed in neurocritical care units. Avoiding hypoxaemia is a key objective in patients with acute brain injury (ABI). However, several studies suggest that hyperoxaemia may also be related to higher mortality and poor neurological outcomes in these patients. The evidence in this direction is still controversial due to the limited number of prospective studies, the lack of a common definition for hyperoxaemia, the heterogeneity in experimental designs and the different causes of ABI. To explore the correlation between hyperoxaemia and poor neurological outcomes and mortality in hospitalised adult patients with ABI, we will conduct a systematic review and meta-analysis of observational studies and RCTs. METHODS AND ANALYSIS: The systematic review methods have been defined according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and follow the PRISMA-Protocols structure. Studies published until June 2024 will be identified in the electronic databases MEDLINE, Embase, Scopus, Web of Science, The Cochrane Library, Cumulative Index to Nursing and Allied Health Literature and ClinicalTrials.gov. Retrieved records will be independently screened by four authors working in pairs, and the selected variables will be extracted from studies reporting data on the effect of 'hyperoxaemia' versus 'no hyperoxaemia on neurological outcomes and mortality in hospitalised patients with ABI. We will use covariate-adjusted ORs as outcome measures when reported since they account for potential cofounders and provide a more accurate estimate of the association between hyperoxaemia and outcomes; when not available, we will use univariate ORs. If the study presents the results as relative risks, it will be considered equivalent to the OR as long as the prevalence of the condition is close to 10%. Pooled estimates of both outcomes will be calculated applying random-effects meta-analysis. Interstudy heterogeneity will be assessed using the I2 statistic; risk of bias will be assessed through Risk Of Bias In Non-Randomised Studies of Interventions, Newcastle-Ottawa or RoB2 tools. Depending on data availability, we plan to conduct subgroup analyses by ABI type (traumatic brain injury, postcardiac arrest, subarachnoid haemorrhage, intracerebral haemorrhage and ischaemic stroke), arterial partial pressure of oxygen values, study quality, study time, neurological scores and other selected clinical variables of interest. ETHICS AND DISSEMINATION: Specific ethics approval consent is not required as this is a review of previously published anonymised data. Results of the study will be shared with the scientific community via publication in a peer-reviewed journal and presentation at relevant conferences and workshops. It will also be shared key stakeholders, such as national or international health authorities, healthcare professionals and the general population, via scientific outreach journals and research institutes' newsletters.


Assuntos
Lesões Encefálicas , Metanálise como Assunto , Revisões Sistemáticas como Assunto , Humanos , Lesões Encefálicas/mortalidade , Lesões Encefálicas/complicações , Hiperóxia/etiologia , Hiperóxia/mortalidade , Projetos de Pesquisa
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