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British Journal of Anaesthesia Oct 2022Peri-intubation oxygen administration to the pregnant patient during induction of general anaesthesia is critical to avoiding hypoxaemia and harm to the mother and...
Peri-intubation oxygen administration to the pregnant patient during induction of general anaesthesia is critical to avoiding hypoxaemia and harm to the mother and fetus. Recent modelling comparing low-flow with high-flow nasal oxygen in simulated term pregnant women of varying body habitus, taken together with previous work, suggests that face mask preoxygenation with the use of low-flow or high-flow nasal oxygen during the period of apnoea prolongs the safe apnoea period, with the benefit varying by body habitus. Low-flow compared with high-flow nasal oxygen may be easier to combine with face mask preoxygenation and is readily available in all operating theatres, although future improvements in high-flow nasal oxygen delivery systems may improve ease of use for this indication.
Topics: Apnea; Cesarean Section; Female; Humans; Hypoxia; Intubation, Intratracheal; Oxygen; Oxygen Inhalation Therapy; Pregnancy
PubMed: 35985842
DOI: 10.1016/j.bja.2022.07.014 -
Chinese Journal of Natural Medicines Jul 2023Natural products exhibit substantial impacts in the field of anti-hypoxic traetment. Hypoxia can cause altitude sickness and other negative effect on the body. Headache,... (Review)
Review
Natural products exhibit substantial impacts in the field of anti-hypoxic traetment. Hypoxia can cause altitude sickness and other negative effect on the body. Headache, coma, exhaustion, vomiting and, in severe cases, death are some of the clinical signs. Currently, hypoxia is no longer just a concern in plateau regions; it is also one of the issues that can not be ignored by urban residents. This review covered polysaccharides, alkaloids, saponins, flavonoids, peptides and traditional Chinese compound prescriptions as natural products to protect against hypoxia. The active ingredients, effectiveness and mechanisms were discussed. The related anti-hypoxic mechanisms involve increasing the hemoglobin (HB) content, glycogen content and adenosine triphosphate (ATP) content, removing excessive reactive oxygen species (ROS), reducing lipid peroxidation, regulating the levels of related enzymes in cells, protecting the structural and functional integrity of the mitochondria and regulating the expression of apoptosis-related genes. These comprehensive summaries are beneficial to anti-hypoxic research and provide useful information for the development of anti-hypoxic products.
Topics: Humans; Biological Products; Hypoxia; Reactive Oxygen Species; Adenosine Triphosphate; Alkaloids
PubMed: 37517818
DOI: 10.1016/S1875-5364(23)60410-8 -
Scientific Reports Oct 2022Osteosarcoma is a primary malignant tumor that often metastasizes in orthopedic diseases. Although multi-drug chemotherapy and surgical treatment have significantly...
Osteosarcoma is a primary malignant tumor that often metastasizes in orthopedic diseases. Although multi-drug chemotherapy and surgical treatment have significantly improved the survival and prognosis of patients with osteosarcoma, the survival rate is still very low due to frequent metastases in patients with osteosarcoma. In-depth exploration of the relationship between various influencing factors of osteosarcoma is very important for screening promising therapeutic targets. This study used multivariate COX regression analysis to select the hypoxia genes SLC2A1 and FBP1 in patients with osteosarcoma, and used the expression of these two genes to divide the patients with osteosarcoma into high-risk and low-risk groups. Then, we first constructed a prognostic model based on the patient's risk value and compared the survival difference between the high expression group and the low expression group. Second, in the high expression group and the low expression group, compare the differences in tumor invasion and inflammatory gene expression between the two groups of immune cells. Finally, the ferroptosis-related genes with differences between the high expression group and the low expression group were screened, and the correlation between these genes was analyzed. In the high-risk group, immune cells with higher tumor invasiveness, macrophages M0 and immune cells with lower invasiveness included: mast cell resting, regulatory T cells (Tregs) and monocytes. Finally, among genes related to ferroptosis, we found AKR1C2, AKR1C1 and ALOX15 that may be related to hypoxia. These ferroptosis-related genes were discovered for the first time in osteosarcoma. Among them, the hypoxia gene FBP1 is positively correlated with the ferroptosis genes AKR1C1 and ALOX15, and the hypoxia gene SLC2A1 is negatively correlated with the ferroptosis genes AKR1C2, AKR1C1 and ALOX15. This study constructed a prognostic model based on hypoxia-related genes SLC2A1 and FBP1 in patients with osteosarcoma, and explored their correlation with immune cells, inflammatory markers and ferroptosis-related genes. This indicates that SLC2A1 and FBP1 are promising targets for osteosarcoma research.
Topics: Female; Humans; Bone Neoplasms; Osteosarcoma; Prognosis; Neoplasm Invasiveness; Hypoxia; Fetal Hypoxia
PubMed: 36316355
DOI: 10.1038/s41598-022-17622-0 -
Journal of Cellular and Molecular... Aug 2021Major advances in the field of genomic technologies have led to an improvement in cancer diagnosis, classification and prognostication. However, many cancers remain... (Review)
Review
Major advances in the field of genomic technologies have led to an improvement in cancer diagnosis, classification and prognostication. However, many cancers remain incurable due to the development of drug resistance, minimal residual disease (MRD) and disease relapse, highlighting an incomplete understanding of the mechanisms underlying these processes. In recent years, the impact of non-genetic factors on neoplastic transformations has increasingly been acknowledged, and growing evidence suggests that low oxygen (O ) levels (ie hypoxia) in the tumour microenvironment play a critical role in the development and treatment of cancer. As a result, there is a growing need to develop research tools capable of reproducing physiologically relevant O conditions encountered by cancer cells in their natural environments in order to gain in-depth insight into tumour cell metabolism and function. In this review, the authors highlight the importance of hypoxia in the pathogenesis of malignant diseases and provide an overview of novel engineering tools that have the potential to further drive this evolving, yet technically challenging, field of cancer research.
Topics: Bioengineering; Humans; Hypoxia; Neoplasm, Residual; Neoplasms; Neoplastic Stem Cells; Tumor Microenvironment
PubMed: 34213838
DOI: 10.1111/jcmm.16759 -
Placenta Sep 2021Intrauterine hypoxia is a feature of pregnancy complications, both at high altitude and sea level. To understand the placental response to reduced oxygen availability,... (Review)
Review
Intrauterine hypoxia is a feature of pregnancy complications, both at high altitude and sea level. To understand the placental response to reduced oxygen availability, small animal models of maternal inhalation hypoxia (MIH) or reduced uterine perfusion pressure (RUPP) may be utilised. The aim of this review was to compare the findings of those studies to identify the role of oxygen availability in adapting placental structural and functional phenotypes in relation to fetal outcome. It also sought to explore the evidence for the involvement of particular genes and protein signalling pathways in the placenta in mediating hypoxia driven alterations. The data available demonstrate that both MIH and RUPP can induce placental hypoxia, which affects placental structure and vascularity, as well as glucose, amino acid, calcium and possibly lipid transport capacity. In addition, changes have been observed in HIF, VEGF, insulin/IGF2, AMPK, mTOR, PI3K and PPARγ signalling, which may be key in linking together observed phenotypes under conditions of placental hypoxia. Many different manipulations have been examined, with varied outcomes depending on the intensity, timing and duration of the insult. Some manipulations have detrimental effects on placental phenotype, viability and fetal growth, whereas in others, the placenta appears to adapt to uphold fetal growth despite the challenge of low oxygen. Together these data suggest a complex response of the placenta to reduced oxygen availability, which links to changes in fetal outcomes. However, further work is required to explore the role of fetal sex, altered maternal physiology and placental molecular mechanisms to fully understand placental responses to hypoxia and their relevance for pregnancy outcome.
Topics: Animals; Disease Models, Animal; Female; Fetal Development; Fetus; Humans; Hypoxia; Placenta; Pregnancy; Signal Transduction
PubMed: 34074553
DOI: 10.1016/j.placenta.2021.03.018 -
Respiratory Care Jul 2023Long-term oxygen therapy (LTOT) is a mainstay treatment for patients with severe resting hypoxemia secondary to chronic respiratory conditions including COPD. The...
Long-term oxygen therapy (LTOT) is a mainstay treatment for patients with severe resting hypoxemia secondary to chronic respiratory conditions including COPD. The evidence for LTOT is based on two trials that are now several decades old but have been insufficiently revisited. Therefore, many questions remain about precisely which patients experience the most benefit from LTOT, as well as how to define that benefit. Most studies have examined LTOT's effect on longevity rather than its impact on quality of life. In addition, many challenges exist in training both clinicians and patients on best practices for LTOT and associated equipment. Reimbursement policies have reduced the kinds of equipment available to the LTOT patient community, presenting additional challenges. This paper will review the current evidence for LTOT in COPD, the challenges involved with providing optimal therapy, and potential avenues of modernizing this essential intervention.
Topics: Humans; Pulmonary Disease, Chronic Obstructive; Quality of Life; Oxygen Inhalation Therapy; Hypoxia; Oxygen
PubMed: 37353334
DOI: 10.4187/respcare.10876 -
BMJ Case Reports May 2021Platypnoea-orthodeoxia syndrome (POS) is a rare entity characterised by respiratory distress and/or hypoxia developing in the sitting/upright posture, which is relieved...
Platypnoea-orthodeoxia syndrome (POS) is a rare entity characterised by respiratory distress and/or hypoxia developing in the sitting/upright posture, which is relieved in the supine posture. It is caused by cardiac, pulmonary and non-cardiopulmonary diseases. COVID-19 can have varying respiratory manifestations including acute respiratory distress syndrome (ARDS) and sequelae-like pulmonary fibrosis. POS has been rarely reported in patients with COVID-19. Here we report a case of POS in a patient recovering from severe COVID-19 ARDS. As he was gradually mobilised after his improvement, he had worsening dyspnoea in the sitting position with significant relief on assuming a supine posture. He was diagnosed with POS after ruling out other causes of POS. He was treated with oxygen support in upright posture and chest physiotherapy was continued, to which he showed improvement. POS is a rare manifestation of COVID-19 which needs awareness as it can be diagnosed easily and can respond to continued supportive care.
Topics: COVID-19; Dyspnea; Foramen Ovale, Patent; Humans; Hypoxia; Male; SARS-CoV-2
PubMed: 33952573
DOI: 10.1136/bcr-2021-243016 -
British Journal of Pharmacology Nov 2023Pulmonary hypertension (PH) is a cardiovascular disease characterised by an increase in pulmonary arterial (PA) resistance leading to right ventricular (RV) failure....
BACKGROUND AND PURPOSE
Pulmonary hypertension (PH) is a cardiovascular disease characterised by an increase in pulmonary arterial (PA) resistance leading to right ventricular (RV) failure. Reactive oxygen species (ROS) play a major role in PH. OP2113 is a drug with beneficial effects on cardiac injuries that targets mitochondrial ROS. The aim of the study was to address the in vivo therapeutic effect of OP2113 in PH.
EXPERIMENTAL APPROACH
PH was induced by 3 weeks of chronic hypoxia (CH-PH) in rats treated with OP2113 or its vehicle via subcutaneous osmotic mini-pumps. Haemodynamic parameters and both PA and heart remodelling were assessed. Reactivity was quantified in PA rings and in RV or left ventricular (LV) cardiomyocytes. Oxidative stress was detected by electron paramagnetic resonance and western blotting. Mitochondrial mass and respiration were measured by western blotting and oxygraphy, respectively.
KEY RESULTS
In CH-PH rats, OP2113 reduced the mean PA pressure, PA remodelling, PA hyperreactivity in response to 5-HT, the contraction slowdown in RV and LV and increased the mitochondrial mass in RV. Interestingly, OP2113 had no effect on haemodynamic parameters, both PA and RV wall thickness and PA reactivity, in control rats. Whereas oxidative stress was evidenced by an increase in protein carbonylation in CH-PH, this was not affected by OP2113.
CONCLUSION AND IMPLICATIONS
Our study provides evidence for a selective protective effect of OP2113 in vivo on alterations in both PA and RV from CH-PH rats without side effects in control rats.
Topics: Rats; Animals; Hypertension, Pulmonary; Reactive Oxygen Species; Heart Ventricles; Pulmonary Artery; Heart Failure; Hypoxia; Ventricular Dysfunction, Right; Ventricular Function, Right; Disease Models, Animal
PubMed: 37351910
DOI: 10.1111/bph.16174 -
Brain : a Journal of Neurology Mar 2021Over the past 50 years, intense research effort has taught us a great deal about multiple sclerosis. We know that it is the most common neurological disease affecting... (Review)
Review
Over the past 50 years, intense research effort has taught us a great deal about multiple sclerosis. We know that it is the most common neurological disease affecting the young-middle aged, that it affects two to three times more females than males, and that it is characterized as an autoimmune disease, in which autoreactive T lymphocytes cross the blood-brain barrier, resulting in demyelinating lesions. But despite all the knowledge gained, a key question still remains; what is the initial event that triggers the inflammatory demyelinating process? While most research effort to date has focused on the immune system, more recently, another potential candidate has emerged: hypoxia. Specifically, a growing number of studies have described the presence of hypoxia (both 'virtual' and real) at an early stage of demyelinating lesions, and several groups, including our own, have begun to investigate how manipulation of inspired oxygen levels impacts disease progression. In this review we summarize the findings of these hypoxia studies, and in particular, address three main questions: (i) is the hypoxia found in demyelinating lesions 'virtual' or real; (ii) what causes this hypoxia; and (iii) how does manipulation of inspired oxygen impact disease progression?
Topics: Animals; Blood-Brain Barrier; Humans; Hypoxia; Mitochondria; Multiple Sclerosis
PubMed: 33351069
DOI: 10.1093/brain/awaa427 -
Revue Medicale Suisse Nov 2022Hypoxemia is defined as a decreased oxygen partial pressure in arterial blood. This frequent clinical phenomenon can lead to tissue hypoxia and requires a prompt...
Hypoxemia is defined as a decreased oxygen partial pressure in arterial blood. This frequent clinical phenomenon can lead to tissue hypoxia and requires a prompt diagnostic approach to guide its management. Five pathophysiological mechanisms should be assessed in the presence of hypoxemia: alveolar hypoventilation, ventilation/perfusion mismatches, diffusion disorders, true shunts and a decrease in the partial pressure of inspired oxygen. In this article, we synthesize the main etiologies of hypoxemia based on respiratory pathophysiology and suggest a diagnostic approach for its evaluation.
Topics: Humans; Hypoxia; Oxygen; Lung
PubMed: 36382976
DOI: 10.53738/REVMED.2022.18.804.2157