Oxygen Supply Research Articles

Rational Construction of Cyanide‐Functionalized D‐A‐π‐D Covalent Organic Framework for Highly Efficient Overall H2O2 Photosynthesis from Air and Water

Sacrificial‐agent‐free overall photosynthesis of H2O2 from water and air represents currently a promising route to reform the industrial anthraquinone production manner, but, still blocks by the requirement of pure O2 feedstock, due to the insufficient oxygen supply from water under air. Herein, we report a rational molecule design on COFs (covalent organic frameworks) equiped with cyanide‐functionalized D‐A‐π‐D system for highly efficient overall H2O2 production from air and water through photocatalytic oxygen reduction reactions (ORR) and water oxidation reaction (WOR). Without using any sacrificial agent, the as‐synthesized D‐A‐π‐D COF is found to enable a H2O2 production rate as high as 4742 μmol h‐1 g‐1 from water and air and an O2 utilization and conversion rate up to 88%, exceeding the other D‐A‐π‐A COF by respectively 1.9‐ and 1.3‐fold. Such high performance is attributed to the tuned electronic structure and prolonged charge lifetime facilitated by the unique D‐A‐π‐D structure and cyanide groups. This work highlights a fundamental molecule design on advanced photocatalytic COFs with complicated D‐A system for low‐cost and massive H2O2 production.

Study on the Spontaneous Combustion Law of Coal Body around a Borehole Induced by Pre-extraction of Coalbed Methane.

To address the challenges associated with the high gas content, high pressure, and low permeability coefficient in deep coal seams, strategies such as infilling boreholes and increasing the negative pressure of extraction are commonly implemented to alleviate issues related to coalbed methane extraction. However, long-term mining pressure can lead to the development of cracks in the coal seam near the borehole, thereby creating air leakage channels, which could potentially impact the oxygen supply during the extraction process. This leads to secondary disasters such as the spontaneous combustion of coal and gas explosions, considerably impacting the life and health of underground workers. To solve this issue, a thermal-fluid-solid coupling model for the working surface was constructed based on numerical simulation software, taking into account the multimechanism coupling effect of coal seam gas. The laws of coal oxidation and spontaneous combustion induced by coalbed methane extraction around boreholes were studied. The variation laws of the oxygen concentration, coal temperature, and oxidation heating zone around the borehole under different extraction conditions were simulated and analyzed. The findings demonstrate that the negative extraction pressure enables the gas to penetrate the fracture zone of the borehole, leading to an increase in the oxygen consumption rate and coal temperature around the borehole with an increase in negative extraction pressure. The coal gas leakage surrounding the borehole reduces as the sealing depth increases, and both the heating rate of coal and oxygen volume fraction show a downward trend. The fitting relationship between the negative pressure of drainage, depth of sealing, and temperature change in the coal body surrounding the boreholes was identified. It was determined that the negative pressure of 13 kPa for borehole drainage and a sealing depth >18 m are the optimal extraction parameters. The range of the oxidation zone and the position of the boundary line under this parameter were predicted, and the position function of the dangerous area of oxidation heating was defined. The research results have remarkable implications for the coordinated prevention and control of gas and coal spontaneous combustion in coalbed methane predrainage boreholes, as well as for efficient prevention and control of CO in on-site gas extraction boreholes, thus ensuring efficient and safe gas extraction.

Hypoglycaemia in screening oral glucose tolerance test in pregnancy with low birth weight fetus.

Maternal hypoglycemia, a condition characterized by lower than normal blood glucose levels in pregnant women, has been increasingly associated with adverse pregnancy outcomes, including low birth weight (LBW) in neonates. LBW, defined as a birth weight of less than 2500 g, can result from various factors, including maternal nutrition, health status, and metabolic conditions like hypoglycemia. Maternal hypoglycemia may affect fetal growth by altering the supply of essential nutrients and oxygen to the fetus, leading to restricted fetal development and growth. This condition poses significant risks not only during pregnancy but also for the long-term health of the child, increasing the likelihood of developmental delays, health issues, and chronic conditions later in life. Research in this area has focused on understanding the mechanisms through which maternal hypoglycemia influences fetal development, with studies suggesting that alterations in placental blood flow and nutrient transport, as well as direct effects on fetal insulin levels and metabolism, may play a role. Given the potential impact of maternal hypoglycemia on neonatal health outcomes, early detection and management are crucial to minimize risks for LBW and its associated complications. Further investigations are needed to fully elucidate the complex interactions between maternal glucose levels and fetal growth, as well as to develop targeted interventions to support the health of both mother and child. Understanding these relationships is vital for improving prenatal care and outcomes for pregnancies complicated by hypoglycemia.

Enhancing prediction of elemental composition through machine learning decision tree models for biomass gasification optimization

Abstract The worldwide transition to cleaner, sustainable energy sources, prompted by population growth and industrialization, responds to uncertain fossil fuel prices and environmental concerns, highlighting the substantial benefits of renewable energy in reducing greenhouse gas emissions and addressing climate change. Derived from non-fossilized organic materials, biomass emerges as a significant and sustainable contributor to renewable energy. Its diverse nature is complemented by a range of conversion technologies, encompassing combustion, pyrolysis, gasification, and liquefaction, providing versatile avenues for biomass energy transformation. Gasification, the transformative process of converting organic matter into combustible gases under controlled oxygen levels, is accomplished through direct oxygen supply or pyrolysis. This method yields a dependable gaseous fuel versatile for heating, industrial processes, power generation, and liquid fuel production. Machine learning employs advanced statistical techniques for modeling across diverse industries, showcasing particular efficacy in optimizing thermochemical processes by precisely identifying the optimal operating conditions required for achieving desired product properties. These models utilize proximate biomass data to predict the elemental compositions of N2 and H2. Assessment of both single and two hybrid models indicated that the introduced optimizers significantly enhanced the estimation of N2 and H2 when combined with Decision Tree (DT), with Decision Tree Coupled with Artificial Hummingbird Algorithm (DTAH) proving particularly effective. Notably, DTAH demonstrated outstanding performance with remarkable R 2 values of 0.990 for N2 and 0.992 for H2. Additionally, the minimal Root Mean Square Error (RMSE) values of 1.291 and 1.550 for N2 and H2 predictions respectively underscore the precision of DTAH, establishing it as a suitable choice for practical real-world applications.

Porous Organic Polymer-Based Nanocomposites for Hypoxia Relieving and Enhanced Chemotherapy in Hepatocellular Carcinoma.

Uncontrolled proliferation and altered metabolism of cancer cells result in an imbalance of nutrients and oxygen supply, and persuade hypoxia. Hypoxia, in turn, activates the transcription gene HIF-1α, which eventually upregulates the efflux transporter P-gp and induces multidrug resistance (MDR). Thus, hypoxia leads to the development of resistance to conventional therapies. Therefore, the fabrication of a nanoscale porous system enriched with upconversion nanoparticles to target cancer cells, evade hypoxia, and enhance anticancer therapy is the key goal of this article. Herein, upconversion nanoparticles are embedded in a nanoscale porous organic polymer (POP) and further conjugated with a targeting moiety and a catalase molecule. The nanoscale POP embedded in UCNPs is generated at room temperature. The targeting ligand, lactobionic acid, is attached after polymer coating, which effectively targets liver cancer cells. Then, catalase is grafted effectively to produce oxygen. Endogenously generated oxygen alleviates hypoxia in liver cancer cells. The drug- and catalase-loaded composite exhibit greater cytotoxicity in hypoxic liver cells than in normal cells by overcoming hypoxia and downregulating the hypoxia-inducible factors.

An Approximate Bayesian Computation Approach for Embryonic Astrocyte Migration Model Reduction.

During embryonic development of the retina of the eye, astrocytes, a type of glial cell, migrate over the retinal surface and form a dynamic mesh. This mesh then serves as scaffolding for blood vessels to form the retinal vasculature network that supplies oxygen and nutrients to the inner portion of the retina. Astrocyte spreading proceeds in a radially symmetric manner over the retinal surface. Additionally, astrocytes mature from astrocyte precursor cells (APCs) to immature perinatal astrocytes (IPAs) during this embryonic stage. We extend a previously-developed continuum model that describes tension-driven migration and oxygen and growth factor influenced proliferation and differentiation. Comparing numerical simulations to experimental data, we identify model equation components that can be removed via model reduction using approximate Bayesian computation (ABC). Our results verify experimental studies indicating that the choroid oxygen supply plays a negligible role in promoting differentiation of APCs into IPAs and in promoting IPA proliferation, and the hyaloid artery oxygen supply and APC apoptosis play negligible roles in astrocyte spreading and differentiation.

233 Exploring the impact of intrauterine growth restriction on fecal microbiota and metabolome in pigs

Abstract Intrauterine growth restriction (IUGR) poses a significant challenge in swine production, affecting approximately 20% of piglets and resulting in increased mortality rates, metabolic disturbances, compromised intestinal development, and altered microbial colonization. This phenomenon arises as the IUGR fetus adapts to limited oxygen and nutrient supply in utero by reallocating blood flow towards vital organs, particularly the brain, consequently leading to a greater brain-to-liver weight ratio (BrW/LW) at birth. Our study aimed to comprehensively investigate the repercussions of IUGR on fecal microbiota composition and plasma metabolome profiles in pigs from birth through to slaughter. To elucidate these effects, we conducted computed tomography scans on piglets within 24 h of birth to assess brain and liver weights accurately. Subsequently, we selected two groups of piglets based on the BrW/LW. Specifically, 12 piglets with the greatest BrW/LW (IUGR; BrW/LW: 1.00 ± 0.09) and 12 with the least BrW/LW (NORM; BrW/LW: 0.36 ± 0.04). From these piglets we collected fecal and blood samples at specific time points: during lactation (T1: d 16 ± 0.6), after the starter period (T2: d 63 ± 8.6), and at the onset (T3: d 119 ± 11.4) and conclusion (T4: d 162 ± 14.3) of the finisher period. Throughout the study, all pigs received identical diets to eliminate dietary confounders. In the lactation, starter and grower but not finisher period, IUGR piglets grew 47, 19 and 14% slower, respectively compared with their NORM littermates. Our findings revealed that fecal microbial α-diversity remained unaffected by IUGR across all time points examined, indicating a stable microbial richness within the gut microbiota of IUGR and NORM pigs. However, β-diversity, reflecting inter-group microbial community variation, exhibited significant differences at T1 (P = 0.002), T2 (P = 0.079), and T3 (P = 0.027), suggesting distinct microbial compositions between IUGR and NORM pigs at these stages. Specifically, IUGR pigs displayed a greater abundance of Clostridium sensu stricto 1 and Romboutsia at T1, Prevotellaceae NK3B31 group, Rikenellaceae RC9 gut group, and Alloprevotella at T2, and p-2534-18B5 gut group at T3. Conversely, the NORM group exhibited increased concentrations of Ruminococcus at T1, HT002 at T2, and Prevotella_9 at T3. Furthermore, while plasma metabolite analysis revealed no significant differences between IUGR and NORM pigs at T1, decreased arginine levels were observed in the IUGR group compared with NORM at T2 (P < 0.05). In conclusion, our study underscores the profound and persistent impact of IUGR on fecal microbiota composition in pigs from birth to the initial stages of the finisher period, while suggesting minimal alterations in the blood metabolome profile throughout various growth stages. These findings provide valuable insights into the long-term consequences of IUGR on swine health and production. This research received funding from the European Union’s Horizon 2020 research and innovation program under a Marie Sklodowska-Curie grant (agreement no. 955374).

Artificial Meshed Vessel-Induced Dimensional Breaking Growth of Human Brain Organoids and Multiregional Assembloids.

Brain organoids are widely used to model brain development and diseases. However, a major challenge in their application is the insufficient supply of oxygen and nutrients to the core region, restricting the size and maturation of the organoids. In order to vascularize brain organoids and enhance the nutritional supply to their core areas, two-photon polymerization (TPP) 3D printing is employed to fabricate high-resolution meshed vessels in this study. These vessels made of photoresist with densely distributed micropores with a diameter of 20 μm on the sidewall, are cocultured with brain organoids to facilitate the diffusion of culture medium into the organoids. The vascularized organoids exhibit dimensional breaking growth and enhanced proliferation, reduced hypoxia and apoptosis, suggesting that the 3D-printed meshed vessels partially mimic vascular function to promote the culture of organoids. Furthermore, cortical, striatal and medial ganglionic eminence (MGE) organoids are respectively differentiated to generate Cortico-Striatal-MGE assembloids by 3D-printed vessels. The enhanced migration, projection and excitatory signaling transduction are observed between different brain regional organoids in the assembloids. This study presents an approach using TPP 3D printing to construct vascularized brain organoids and assembloids for enhancing the development and assembly, offering a research model and platform for neurological diseases.

Maternal physical activity in healthy pregnancy: Effect on fetal oxygen supply.

We review evidence for effects of physical activity before and during gestation on the course of pregnancy and ask if there are circumstances where physical activity can stress the fetus due to competition for oxygen and energy substrates. We first summarize physiological responses to exercise in nonpregnant people and known physiological adaptations to pregnancy. Comparing the two, we conclude that physical activity prior to and continuing during gestation is beneficial to pregnancy outcome. The effect of starting an exercise regimen during pregnancy is less easy to assess as few studies have been undertaken. Results from animal models suggest that the effects of maternal exercise on the fetus are transient; the fetus can readily compensate for a short-term reduction in oxygen supply. In general, we conclude that physical activity before and during pregnancy is beneficial, and exercise started during pregnancy is unlikely to affect fetal development. We caution, however, that there are circumstances where this may not apply. They include the intensive exercise regimens of elite athletes and pregnancies at high altitudes where hypoxia occurs even in the resting state.

Impact of elevated IOP on lamina cribrosa oxygenation; A combined experimental-computational study on monkeys.

Our goal is to evaluate how lamina cribrosa (LC) oxygenation is affected by the tissue distortions resulting from elevated IOP. Experimental study on monkeys. Four healthy monkey eyes with OCT scans with IOP of 10 to 50 mmHg, and then with histological sections of LC. Since in-vivo LC oxygenation measurement is not yet possible, we used 3D eye-specific numerical models of the LC vasculature which we subjected to experimentally-derived tissue deformations. We reconstructed 3D models of the LC vessel networks of 4 healthy monkey eyes from histological sections. We also obtained in-vivo IOP-induced tissue deformations from a healthy monkey using OCT images and digital volume correlation analysis techniques. The extent that LC vessels distort under a given OCT-derived tissue strain remains unknown. We therefore evaluated two biomechanics-based mapping techniques: cross-sectional and isotropic. The hemodynamics and oxygenations of the four vessel networks were simulated for deformations at several IOPs up to 60mmHg. The results were used to determine the effects of IOP on LC oxygen supply, assorting the extent of tissue mild and severe hypoxia. IOP-induced deformation, vasculature structure, blood supply, and oxygen supply for LC region. IOP-induced deformations reduced LC oxygenation significantly. More than 20% of LC tissue suffered from mild hypoxia when IOP reached 30 mmHg. Extreme IOP(>50mmHg) led to large severe hypoxia regions (>30%) in the isotropic mapping cases. Our models predicted that moderately elevated IOP can lead to mild hypoxia in a substantial part of the LC, which, if sustained chronically, may contribute to neural tissue damage. For extreme IOP elevations, severe hypoxia was predicted, which would potentially cause more immediate damage. Our findings suggest that despite the remarkable LC vascular robustness, IOP-induced distortions can potentially contribute to glaucomatous neuropathy.

Saturated dissolved oxygen-driven high-rate and ultrastable partial nitrification in municipal wastewater

Achieving stable and high-rate partial nitrification (PN) remains a worldwide technical conundrum in low-strength mainstream conditions. This study successfully achieved ultrarapid mainstream PN within 8 days under a saturated dissolved oxygen (DO) supply strategy, reaching a record-breaking PN rate of over 1.0 kg N m−3 d−1 treating municipal wastewater. Stable PN was maintained for over 200 days with an ultrahigh nitrite accumulation ratio of 98.5 ± 0.9 %, resilient to seasonal fluctuations in temperature (16.0–25.6 °C) and load (NH4+-N, 40–80 mg N/L). Kinetics revealed a remarkable 159.1-fold increase in the maximum activity ratio of ammonia-oxidizing bacteria (AOB) to nitrite-oxidizing bacteria (NOB). The faster response of AOB to saturated DO stimulated its highest activity difference with NOB, contributing to the AOB (Nitrosomonas oligotropha) boom and the elimination of NOB groups (−99.9 %). Our results highlight the importance of promoting AOB rather than solely focusing on NOB suppression for initiating and stabilizing high-rate mainstream PN.

Hypoxia and loss of GCM1 expression prevents differentiation and contact inhibition in human trophoblast stem cells.

The placenta develops alongside the embryo and nurtures fetal development to term. During the first stages of embryonic development, due to low blood circulation, the blood and ambient oxygen supply is very low (∼1-2% O 2 ) and gradually increases upon placental invasion. While a hypoxic environment is associated with stem cell self-renewal and proliferation, persistent hypoxia may have severe effects on differentiating cells and could be the underlying cause of placental disorders. We find that human trophoblast stem cells (hTSC) thrive in low oxygen, whereas differentiation of hTSC to trophoblast to syncytiotrophoblast (STB) and extravillous trophoblast (EVT) is negatively affected by hypoxic conditions. The pro-differentiation factor GCM1 (human Glial Cell Missing-1) is downregulated in low oxygen, and concordantly there is substantial reduction of GCM1-regulated genes in hypoxic conditions. Knockout of GCM1 in hTSC caused impaired EVT and STB formation and function, reduced expression of differentiation-responsive genes, and resulted in maintenance of self-renewal genes. Treatment with a PI3K inhibitor reported to reduce GCM1 protein levels likewise counteracts spontaneous or directed differentiation. Additionally, chromatin immunoprecipitation of GCM1 showed enrichment of GCM1-specific binding near key transcription factors upregulated upon differentiation including the contact inhibition factor CDKN1C. Loss of GCM1 resulted in downregulation of CDKN1C and corresponding loss of contact inhibition, implicating GCM1 in regulation of this critical process.

Ascorbic acid-containing compound efficacy in ischemic brain damage

Introduction: Ischemic brain injury remains one of the main causes of disability and mortality worldwide. Protection of cellular population, depriving from oxygen supply and nutrients, is of extreme importance for further both clinical and health outcomes of timely implemented intravascular intervention. The aim: to assess anti-ischemic activity of 3-hydroxypyridine ascorbate in the in vitro and in vivo models of brain cell and tissue response to ischemia and reoxygenation. Materials and Methods: 3-hydroxypyridine ascorbate (laboratory code 3-EA) was assessed as chemical substance (purity 99.8%) diluted in sterile phosphate-buffered saline. Intracellular Ca2+ response to glutamate excitotoxicity (GluTox), ischemia and reoxygenation as well as cellular viability was evaluated on NMRI murine fresh cortical neuro-glial cell culture incubated with 2-EA by registering intracellular Fura-2 and propidium iodide fluorescence respectively. Expression of apoptosis regulating genes BCL-2, STAT3, SOCS3, inflammation regulating genes TRAIL, MLKL, Cas-1, Cas-3, IL-1β и TNFα, and genes MAO-A and MAO-B was determined by real-time PCR. The substance neuroprotection was studied in male Sprague-Dawley rats with intraluminal middle cerebral artery (MCA) occlusion/reperfusion treated with 18 mg/kg of 2-EA along with neurological deficiency evaluation and morphological assessment of brain sections. Results: Preincubation of cortical cells with 10-100 μM of 3-EA leads to inhibition of [Ca2+]i in cytosol of neurons and astrocytes under GluTox and oxygen-glucose deprivation (OGD) conditions. Reducing [Ca2+]i inhibits necrotic cell death in an acute experiment. Incubation of cerebral cortex cells with 3-EA leads to an overexpression of anti-apoptotic genes BCL-2, STAT3, SOCS3, along with downregulation of genes TRAIL, MLKL, Cas-1, Cas-3, IL-1β and TNFα. Intraperitoneal administration of 3-EA reduces the volume of necrotic areas, perinecrotic edema, cell damage, and neurological deficits in rats with MCA occlusion. Conclusion: 3-EA dose-dependently suppresses the death of cerebral cortex cells under the excitotoxic effects of glutamate and ischemia/reoxygenation. Cell-protective effect of 3-EA involves changes in the basal and ischemia/reoxygenation-induced expression of genes encoding anti-apoptotic proteins and oxidative status proteins, which leads to inhibition of the late irreversible stages of apoptosis. A course administration of 3-hydroxypyridine ascorbate at a dose of 18 mg/kg per day reduces the severity of damage both by preserving the population of neurons in the penumbra zone and by limiting the local stress response.

Exploring the Thioredoxin System as a Therapeutic Target in Cancer: Mechanisms and Implications.

Cells constantly face the challenge of managing oxidants. In aerobic organisms, oxygen (O2) is used for energy production, generating reactive oxygen species (ROS) as byproducts of enzymatic reactions. To protect against oxidative damage, cells possess an intricate system of redox scavengers and antioxidant enzymes, collectively forming the antioxidant defense system. This system maintains the redox equilibrium and enables the generation of localized oxidative signals that regulate essential cellular functions. One key component of this defense is the thioredoxin (Trx) system, which includes Trx, thioredoxin reductase (TrxR), and NADPH. The Trx system reverses oxidation of macromolecules and indirectly neutralizes ROS via peroxiredoxin (Prx). This dual function protects cells from damage accumulation and supports physiological cell signaling. However, the Trx system also shields tumors from oxidative damage, aiding their survival. Due to elevated ROS levels from their metabolism, tumors often rely on the Trx system. In addition, the Trx system regulates critical pathways such as proliferation and neoangiogenesis, which tumors exploit to enhance growth and optimize nutrient and oxygen supply. Consequently, the Trx system is a potential target for cancer therapy. The challenge lies in selectively targeting malignant cells without disrupting the redox equilibrium in healthy cells. The aim of this review article is threefold: first, to elucidate the function of the Trx system; second, to discuss the Trx system as a potential target for cancer therapies; and third, to present the possibilities for inhibiting key components of the Trx system, along with an overview of the latest clinical studies on these inhibitors.

Unexpected Grave’s-induced acute myocardial infarction in a young female, a literature review based on a case report

IntroductionMyocardial ischemia can occur due to several causes, which result in an imbalance between the supply and demand of oxygen to cardiac muscles. One potential reason for this condition is the overwork of the heart due to hyperstimulated thyroid function.Case presentationThe patient was a 36-year-old woman who presented with left-sided chest pain, dyspnea, palpitation, and tremor. The initial evaluation showed evidence of myocardial ischemia (positive high-sensitivity troponin) caused by a hyperactive thyroid gland. The treatment for myocardial infarction, along with anti-thyroid medications, improved the patient’s condition and subsided the symptoms. The coronary angiography revealed no pathologic finding, and the hypokinetic left ventricle, observed in the first echocardiogram, was resolved. The patient was discharged with an excellent clinical condition, and after the 4-month taking of a calcium channel blocker and tapering carbimazole, the thyroid function became normal, and her symptoms resolved completely.ConclusionPatients without evident risk factors for ischemic heart disease, such as non-diabetic, nonsmoker, and young individuals who presented with acute coronary syndrome, should be evaluated for a potential background reason for the imbalance between the oxygen demand and supply of the myocardium. The presence of palpitation, weight loss, tremors, insomnia, and anxiousness, along with ischemic signs, should make the physician think about the probability of the hyperthyroid-induced cardiovascular disorder.Clinical key pointThe initial presentation of hyperthyroidism might be accompanied by severe cardiac symptoms. When the demographic features are not aligned with usual ischemic heart disease, other probable symptoms and signs should be investigated, and thyroid function should be checked. The control of thyroid hyperactivity would result in the resolution of both cardiac and non-cardiac symptoms.

Randomized crossover trial of a demand oxygen delivery system in nocturnal hypoxemia

The newly developed portable oxygen concentrator with an auto-demand oxygen delivery system (auto-DODS) automatically switches between 3 sensitivities according to the negative pressure gradient of inhalation and supplies oxygen only during inhalation. The aim of this study was to verify the effectiveness and safety of auto-demand devices compared with a continuous flow oxygen concentrator, during sleep, in a randomized crossover noninferiority trial. We alternatively used an auto-DODS or a continuous-flow oxygen concentrator, all night on separate days for HOT (Home Oxygen Therapy) patients with nocturnal hypoxemic symptoms. The primary endpoints were the mean value of oxygen saturation (SpO2) over the total sleep time. The secondary endpoints included the efficacy endpoints and the safety endpoints. Regarding the primary endpoint, the difference in SpO2 between the auto-DODS and continuous flow was 0.835%. Since the upper limit of this difference did not exceed 2.8, which was set as the noninferiority margin, it was shown that the auto-DODS did not reduce SpO2 by at least 2.8% on average compared to continuous flow. No equipment failure or exacerbation of disease was observed, confirming the safety of the auto-DODS during the night.

B<sub>12</sub> deficiency: vital aspects and valid clinical applicability of succinate containing cyanocobalamin

The aim of the research is to review the vital pathological processes in B12 insufficiency and the clinical justification for the use of succinate to potentiate the biological activity of cyanocobalamin. It has been shown that one of the possible reasons for the low clinical efficacy of cyanocobalamin is energy deficiency. The energy deficit is caused by a malfunction of the energy metabolism occurring in conditions of low oxygen supply. In the course of clinical studies, it was found that the double injection of succinate containing cyanocobalamin to cows in the highest possible single doses provided rapid normalization of the reserve alkalinity index and ketone bodies. This effect indicated a qualitative improvement in the processes of energy metabolism occurring in the liver. This was also indicated by a decrease in the physiological values of protein and transamination enzymes AlAT and AsAT. On the contrary, the use of pharmacopoeial cyanocobalamin had no significant effect. Thus, there is every reason to believe that the inclusion of sodium succinate in cyanocobalamin is justified, since it allows to qualitatively improve the biological activity of the drug.

Improving effective coverage of medical-oxygen services for neonates and children in health facilities in Uganda: a before–after intervention study

Medical oxygen services are essential for the care of acutely unwell patients. We aimed to assess the effects of a multilevel, multicomponent health-system intervention on hypoxaemia detection, oxygen therapy, and mortality among neonates and children attending level IV health centres and hospitals in Uganda. For this before-after intervention study, we included children who attended paediatric or neonatal wards of 24 level IV health centres and seven general or regional referral hospitals in the Busoga and North Buganda regions of Uganda between June 1, 2020, and June 30, 2022. All neonates younger than 1 month and children aged 1 month to 14 years were eligible for inclusion. We excluded neonates who were not sick but stayed in the maternity ward for routine postnatal care. The intervention involved clinical training, mentorship, and supportive supervision; provision of pulse oximeters and cylinder-based oxygen sources; biomedical-capacity support; and support to develop and disseminate oxygen supply strategies, oxygen therapy guidelines, and lists of essential oxygen supplies. Trained research assistants extracted individual patient data from case notes using a standardised electronic data collection form. Data were collected on health-facility details, age, sex, clinical signs and symptoms, admission diagnoses, pulse oximetry readings, oxygen therapy details, and final patient outcome. The primary outcome was the proportion of admitted neonates and children with a pulse oximetry oxygen saturation reading documented in their patient case notes on day 1 of health-facility admission (ie, pulse oximetry coverage). We used mixed-effects logistic regression to evaluate the effect of the intervention. We obtained data on 71 997 eligible neonates and children admitted to 31 participating health facilities; the primary analysis included 10 001 patients in the pre-intervention period (ie, June 1 to Oct 30, 2020) and 51 329 patients in the post-intervention period (ie, March 1, 2021, to June 30, 2022). Because 1356 patients had missing data for sex, 4365 (46·7%) of 9347 in the pre-intervention group and 22 831 (46·2%) of 49 410 in the post-intervention group were female; 4982 (53·3%) in the pre-intervention group and 26 579 (53·8%) in the post-intervention group were male. The proportion of neonates and children with pulse oximetry at admission increased from 2365 (23·7%) of 10 001 in the pre-intervention period to 45 029 (87·7%) of 51 328 in the post-intervention period. Adjusted analysis indicated greater likelihood of a patient receiving pulse oximetry during the post-intervention period compared with the pre-intervention period (adjusted odds ratio 40·10, 95% CI 37·38-42·93; p<0·0001). Large-scale improvements in hospital oxygen services are achievable and have the potential to improve clinical outcomes. Governments should be encouraged to develop national oxygen plans and focus investment on interventions that have been shown to be effective, including the introduction of pulse oximetry into routine hospital care and clinical and biomedical mentoring and support. Bill & Melinda Gates Foundation and ELMA Philanthropies. For the Luganda and Lusoga translations of the abstract see Supplementary Materials section.

Heterogeneous corrosion of carbon steel used for casing in deep geological radioactive waste repository in contact with claystone

The corrosion of C-steel in contact with the Cox claystone was studied under aerated conditions at 50°C, for 7 years, in a simplified laboratory experiment. A multi-scale and multi-technique approach, including SEM-EDX, Raman spectroscopy and STXM, was used to determine the nature and structure of the corrosion products and to better understand the mechanisms involved in the observed degradation. The effects of temperature, oxygen supply and the local influence of the composition and density of the claystone were examined here.

Association of COVID with Mycosis in General.

The COVID-19 pandemic caused by SARS-CoV-2 is a respiratory disease which created havoc worldwide, was accompanied by another peculiar, otherwise rare, secondary fungal infection Mucormycosis which was observed at exceptionally high incidence in India during the second wave of COVID-19. The article explores possible links between the two infectious diseases to understand a higher-than-normal occurrence of Mucormycosis in COVID-19 patients. Coronavirus enters the patients through ACE-2 and many other receptors like- NRP-1, TfR, CD-126, and CD-26. Virus bind to cells possessing these receptors and affect their proper functioning, disturbing homeostatic metabolism and resulting in conditions like hyperglycemia, Diabetic Ketoacidosis (DKA), low serum pH, iron overload, anemia, hypoxia, and immunosuppression as explained in the article. All these outcomes provide a very supportive environment for the attack and spread of Mucormycosis fungi. The major receptor for Mucormycosis in humans is the GRP-78. Its expression is upregulated by coronavirus entry and by hyperferritinemia, hyperglycemia, and acidic conditions prevalent in COVID patients, thus providing an easy entry for the fungal species. Upregulation of GRP-78 furthermore damages pancreatic β-cells and intensifies hyperglycemia, showing quite a synergic relationship. Inordinate rise of Mucormycosis cases in India might be explained by facts like- India possessing a large proportion of diabetic patients, emergence of a very deadly strain of coronavirus- Delta strain, higher doses of steroids and antibodies used to treat patients against this strain, overburdened health care services, sudden much higher need of oxygen supply and use of industrial oxygen could explain the Mucormycosis outbreak observed in India during the second wave of COVID-19. The present review discusses the functional interdependence between COVID-19 and Mucormycosis and summarizes the possible synergic links between COVID and Mucormycosis. The receptors and metabolic pathways affected by COVID-19 result in severe physiological conditions- hyperglycemia, DKA, anemia, iron overload, immunosuppression, and hypoxia. All these conditions not only increase the expression of GRP-78, the major receptor for entry of fungi but also play a crucial role in providing quality media for Mucormycosis fungus to establish and grow. Hence explains the fungal epidemic observed in India during the second wave of COVID-19 in India.