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In the field of electrical engineering, complex coding and signal processing techniques are the norm. Thus, it is refreshing to consider the amount of planetary science that can be done simply by using a high-quality radio. The radio, usually located on an exploring spacecraft, transmits a simple, single-frequency, sinusoidal tone that sweeps through a planet's atmosphere. After the electromagnetic energy passes through the atmosphere, it is received on the other side of the planet. Then, researchers analyze and detect the changes in the received signal energy caused by the interaction with the planet's atmosphere. The information from the received signal is used to determine the number density of particles, the temperature, and the pressure of the volume of atmosphere that the signal passed through. This method of remote sensing is known as radio occultation. The technique was first used in the summer of 1965 to measure the surface pressure on Mars. Since then, the atmospheres of all of the planets in the solar system (except for Pluto), and of some satellites, have been studied just by using a simple, sinusoidal radio signal. With continued application of the radio occultation method and with the development and implementation of higher-output multiple spacecraft constellations, the future promises to be even more productive. [ABSTRACT FROM PUBLISHER]

In recent years, cell-based therapies have emerged as a promising approach for mitigating radiation-induced injury. Acute radiation syndrome (ARS) results from exposure to high doses of radiation over a short time period. This study aimed to compare the efficacy of donor-recipient chimeric cell (DRCC) therapy in mitigating ARS induced by a total body irradiation (TBI) dose of 10 gray (Gy). Thirty irradiated Lewis rats were employed as ARS models to assess the efficacy of systemic-intraosseous transplantation of different cellular therapies in five experimental groups ( n = 6/group): saline control, isogenic bone marrow transplantation (isoBMT), allogeneic BMT (alloBMT), DRCC, and alloBMT+DRCC. DRCC were created by polyethylene glycol-mediated fusion of bone marrow cells from 24 ACI (RT1 a ) and 24 Lewis (RT1 1 ) rat donors. The creation of DRCC and chimeric state was confirmed by flow cytometry (FC) and confocal microscopy (CM). Recovery of blood parameters was evaluated through complete blood count analysis. Graft-versus-host disease (GvHD) signs were assessed clinically and histopathologically using kidney, skin, and small intestine biopsies. FC and CM confirmed the fusion feasibility and the chimeric state of DRCC. A 100% mortality rate was observed in the saline control group, whereas a 100% survival was recorded following DRCC transplantation, correlating with significant recovery of peripheral blood parameters. In addition, no clinical or histopathological signs of GvHD were observed after DRCC and alloBMT+DRCC transplantation. These findings confirm efficacy of DRCC in mitigating GvHD, promoting hematopoietic recovery, and increasing animal survival following TBI-induced ARS. Moreover, tolerogenic and immunomodulatory properties of DRCC therapy support its feasibility for clinical applications. Therefore, this study introduces DRCC as an innovative bridging therapy for alleviating the acute effects of TBI, with broad implications for stem cell research and regenerative medicine.

Background: Exposure to high doses of total body irradiation (TBI) may lead to the development of acute radiation syndrome (ARS). This study was conducted to establish an experimental rat model of TBI to assess the impact of different doses of TBI on survival and the kinetics of changes within the hematopoietic system in ARS., Materials and Methods: In this study, 132 Lewis rats irradiated with a 5Gy or 7Gy dose served as experimental models to induce ARS and to evaluate the hematopoietic response of the bone marrow (BM) compartment. Animals were divided into 22 experimental groups (n = 6/group): groups 1-11 irradiated with 5Gy dose and groups 12-22 irradiated with 7Gy dose. The effects of TBI on the hematopoietic response were assessed at 2, 4, 6, 8 hours and 5, 10, 20, 30, 40, 60 and 90 days following TBI. Signs of ARS were evaluated by analyzing blood samples through complete blood count in addition to the clinical assessment., Results: Groups irradiated with 5Gy TBI showed 100% survival, whereas after 7Gy dose, 1.6% mortality rate was observed. Assessment of the complete blood count revealed that lymphocytes were the first to be affected, regardless of the dose used, whereas an "abortive rise" of granulocytes was noted for both TBI doses. None of the animals exhibited signs of severe anemia or thrombocytopenia. All animals irradiated with 5Gy dose regained initial values for all blood cell subpopulations by the end of observation period. Body weight loss was reported to be dose-dependent and was more pronounced in the 7Gy groups. However, at the study end point at 90 days, all animals regained or exceeded the initial weight values., Conclusions: We have successfully established a rat experimental model of TBI. This study revealed a comparable hematopoietic response to the sublethal or potentially lethal doses of ionizing radiation. The experimental rat model of TBI may be used to assess different therapeutic approaches including BM-based cell therapies for long-term reconstitution of the hematopoietic and BM compartments allowing for comprehensive analysis of both the hematological and clinical symptoms associated with ARS., Competing Interests: Conflicts of Interest and Source of Funding: This work was supported by the Defense Advanced Research Projects Agency DARPA-BAA-14-38 effort under award no. W911NF-14-1-0323, and the U.S. Army Contracting Command - Aberdeen Proving Ground (ACC-APG), 4300 Miami Boulevard Durham, NC 27703. Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the Department of Defense. The authors declare no potential conflict of interests., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Current therapies for acute radiation syndrome (ARS) involve bone marrow transplantation (BMT), leading to graft-versus-host disease (GvHD). To address this challenge, we have developed a novel donor-recipient chimeric cell (DRCC) therapy to increase survival and prevent GvHD following total body irradiation (TBI)-induced hematopoietic injury without the need for immunosuppression. In this study, 20 Lewis rats were exposed to 7 Gy TBI to induce ARS, and we assessed the efficacy of various cellular therapies following systemic intraosseous administration. Twenty Lewis rats were randomly divided into four experimental groups ( n = 5/group): saline control, allogeneic bone marrow transplantation (alloBMT), DRCC, and alloBMT + DRCC. DRCC were created by polyethylene glycol-mediated fusion of bone marrow cells from 24 ACI (RT1a) and 24 Lewis (RT11) rat donors. Fusion feasibility was confirmed by flow cytometry and confocal microscopy. The impact of different therapies on post-irradiation peripheral blood cell recovery was evaluated through complete blood count, while GvHD signs were monitored clinically and histopathologically. The chimeric state of DRCC was confirmed. Post-alloBMT mortality was 60%, whereas DRCC and alloBMT + DRCC therapies achieved 100% survival. DRCC therapy also led to the highest white blood cell counts and minimal GvHD changes in kidney and skin samples, in contrast to alloBMT treatment. In this study, transplantation of DRCC promoted the recovery of peripheral blood cell populations after TBI without the development of GVHD. This study introduces a novel and promising DRCC-based bridging therapy for treating ARS and extending survival without GvHD., (© 2024 Maria Siemionow et al., published by Sciendo.)

Intraoperative hypotension (IH) is common in patients receiving general anesthesia and can lead to serious complications such as kidney failure, myocardial injury and increased mortality. The Hypotension Prediction Index (HPI) algorithm is a machine learning system that analyzes the arterial pressure waveform and alerts the clinician of an impending hypotension event. The purpose of the study was to compare the frequency of perioperative hypotension in patients undergoing major abdominal surgery with different types of hemodynamic monitoring. The study included 61 patients who were monitored with the arterial pressure-based cardiac output (APCO) technology (FloTrac group) and 62 patients with the Hypotension Prediction Index algorithm (HPI group). Our primary outcome was the time-weighted average (TWA) of hypotension below < 65 mmHg. The median TWA of hypotension in the FloTrac group was 0.31 mmHg versus 0.09 mmHg in the HPI group ( p = 0.000009). In the FloTrac group, the average time of hypotension was 27.9 min vs. 8.1 min in the HPI group ( p = 0.000023). By applying the HPI algorithm in addition to an arterial waveform analysis alone, we were able to significantly decrease the frequency and duration of perioperative hypotension events in patients who underwent major abdominal surgery.

One of the target of perioperative tratment in surgery is decreasing intraoperative bleeding, which increases the number of perioperative procedures, mortality and treatment costs, and also causes the risk of transfusion of blood and its components. Trying to minimize the blood loss(mainly during the operation) as well as the need to transfuse blood and its components (broadly understood perioperative period) should be standard treatment for a patient undergoing a procedure. In the case of this method, the following steps should be taken: 1) in the preoperative period: identyfication of risk groups as quickly as possible, detecting and treating anemia, applying prehabilitation, modyfying anticoagulant treatment, considering donating one&apos;s own blood in some patients and in selected cases erythropoietin preparations; 2) in the perioperative period: aim for normothermia, normovolemia and normoglycemia, use of surgical methods that reduce bleeding, such as minimally invasive surgery, high-energy coagulation, local hemostatics, prevention of surgical site infection, proper transfusion of blood and its components if it occurs; 3) in the postoperative period: monitor the condition of patients, primarily for the detection of bleeding, rapid reoperation if required, suplementation (oral administration preferred) nutrition with microelements (iron) and vitamins, updating its general condition. All these activities, comprehensively and in surgical cooperation with the anesthesiologist, should reduce the blood loss and transfusion of blood and its components.

Background: Prevention and treatment of haemodynamic instability and increased intracranial pressure (ICP) in patients with subarachnoid haemorrhage (SAH) is vital. This study aimed to evaluate the effects of protocolised cerebral perfusion pressure (CPP)-guided treatment on morbidity and functional outcome in patients admitted to the intensive care unit (ICU) with SAH., Methods: We performed a retrospective study comparing 37 patients who received standard haemodynamic treatment (control group) with 17 individuals (CPP-guided group) who were on the CPP-guided treatment aimed at maintaining CPP > 70 mmHg using both optimisations of ICP and mean arterial pressure (MAP)., Results: MAP, cumulative crystalloid doses and fluid balance were similar in both groups. However, the incidence of delayed cerebral ischaemia was significantly lower in the CPP-guided group (14% vs. 64%, p < 0.01), and functional outcome as assessed by the Glasgow Outcome Scale at 30 days after SAH was improved (29.0% vs. 5.5%, p = 0.03)., Conclusions: This preliminary analysis showed that implementing a CPP-guided treatment approach aimed at maintaining a CPP > 70 mmHg may reduce the occurrence of delayed cerebral ischaemia and improve functional outcomes in patients with SAH. This observation merits further prospective investigation of the use of CPP-guided treatment in patients with SAH.

Central venous catheters are essential elements enabling the treatment of intensive care unit patients. However, these catheters are sometimes colonised by both bacteria and fungi, and thus, they may become a potential source of systemic infections-catheter-related bloodstream infections (CRBSI). The identification of the pathogen responsible for CRBSI is a time-consuming process. At the same time, the relationship between the quick identification of the pathogen and the implementation of targeted antibiotic therapy is of key importance for controlling the clinical symptoms of sepsis and septic shock in the patient. Quick diagnosis is of key importance to reduce morbidity and mortality in this group of patients. In our study, we attempted to create a catalogue of images of the most commonly cultured pathogens responsible for CRBSI. An FEI Quanta 250 FEG Scanning Electron Microscope (SEM) was used for measurements. SEM images obtained during the analysis were included in this study. Images of SEM are three-dimensional and comparable to the images seen with the human eye and are a tool used for research and measurement whenever it is necessary to analyse the state of the surface and assess its morphology. The method described in our study will not replace the current procedures recognised as the gold standard, i.e., pathogen culturing, determination of the count of microorganisms (CFU -colony forming units), and assessment of drug sensitivity. However, in some cases, the solution proposed in our study may aid the diagnosis of patients with suspected catheter-related bloodstream infections leading to sepsis and septic shock.

Intraoperative hypotension (IH) is a frequent phenomenon affecting a substantial number of patients undergoing general anesthesia. The occurrence of IH is related to significant perioperative complications, including kidney failure, myocardial injury, and even increased mortality. Despite advanced hemodynamic monitoring and protocols utilizing goal directed therapy, our management is still reactive; we intervene when the episode of hypotension has already occurred. This literature review evaluated the Hypotension Prediction Index (HPI), which is designed to predict and reduce the incidence of IH. The HPI algorithm is based on a machine learning algorithm that analyzes the arterial pressure waveform as an input and the occurrence of hypotension with MAP <65 mmHg for at least 1 min as an output. There are several studies, both retrospective and prospective, showing a significant reduction in IH episodes with the use of the HPI algorithm. However, the level of evidence on the use of HPI remains very low, and further studies are needed to show the benefits of this algorithm on perioperative outcomes.

The purpose of this review was to summarize the anti-inflammatory and immunosuppressive properties of volatile anesthetics and present their potential impact on the outcomes of major surgical procedures as well as microsurgical cases of free tissue transfer. Inhaled anesthetics are commonly used as a component of general anesthesia in interventional procedures, reconstructive surgery, free tissue transfers and transplantation. Experimental and clinical studies have shown that volatile anesthetics such as halothane, sevoflurane, isoflurane or desflurane can affect the immune system of patients exposed to general anesthesia. In patients with no serious systemic diseases, this effect is transient and mostly clinically irrelevant. However, in patients subjected to the inflammatory response due to the active disease, cardiac or pulmonary failure or advanced age, the prognosis may improve or worsen following inhalation anesthesia depending on the type of systemic pathology. The available data from reported clinical trials, as well as the in vitro and in vivo experimental studies, have often reported conflicting statements regarding the impact of inhalation anesthetics on outcomes of surgical procedures. These differences may be due to the heterogeneity of the evaluated patients, the extent and duration of surgical procedures, and different experimental design and methodologies applied for assessment of the reported clinical and research studies. In this review, based on the available literature reports we have summarized the anti-inflammatory and immunosuppressive effects as well as cellular responses of inhalation anesthetics at the microcirculatory level and discussed their potential clinical implications for the outcomes of surgical procedures of free tissue transfers., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2021 Termedia Sp. z o. o.)

Base excess (BE) and lactate concentration may predict mortality in critically ill patients. However, the predictive values of alactic BE (aBE; the sum of BE and lactate), or a combination of BE and lactate are unknown. The study aimed to investigate whether BE, lactate, and aBE measured on admission to ICU may predict the 28-day mortality for patients undergoing any form of shock. In 143 consecutive adults, arterial BE, lactate, and aBE were measured upon ICU admission. Receiver Operating Curve (ROC) characteristics and Cox proportional hazard regression models (adjusted to age, gender, forms of shock, and presence of severe renal failure) were then used to investigate any association between these parameters and 28-day mortality. aBE < −3.63 mmol/L was found to be associated with a hazard ratio of 3.19 (HR; 95% confidence interval (CI): 1.62−6.27) for mortality. Risk of death was higher for BE < −9.5 mmol/L (HR: 4.22; 95% CI: 2.21−8.05), particularly at lactate concentrations > 4.5 mmol/L (HR: 4.62; 95% CI: 2.56−8.33). A 15.71% mortality rate was found for the combined condition of BE > cut-off and lactate < cut-off. When BE was below but lactate above their respective cut-offs, the mortality rate increased to 78.91%. The Cox regression model demonstrated that the predictive values of BE and lactate were mutually independent and additive. The 28-day mortality in shock patients admitted to ICU can be predicted by aBE, but BE and lactate deliver greater prognostic value, particularly when combined. The clinical value of our findings deserves further prospective evaluation.

The coronavirus disease (COVID-19) pandemic caused unprecedented research activity all around the world but publications from Central-Eastern European countries remain scarce. Therefore, our aim was to characterise the features of the pandemic in the intensive care units (ICUs) among members of the SepsEast (Central-Eastern European Sepsis Forum) initiative. We conducted a retrospective, international, multicentre study between March 2020 and February 2021. All adult patients admitted to the ICU with pneumonia caused by COVID-19 were enrolled. Data on baseline and treatment characteristics, organ support and mortality were collected. Eleven centres from six countries provided data from 2139 patients. Patient characteristics were: median 68, [IQR 60-75] years of age; males: 67%; body mass index: 30.1 [27.0-34.7]; and 88% comorbidities. Overall mortality was 55%, which increased from 2020 to 2021 (p = 0.004). The major causes of death were respiratory (37%), cardiovascular (26%) and sepsis with multiorgan failure (21%). 1061 patients received invasive mechanical ventilation (mortality: 66%) without extracorporeal membrane oxygenation (n = 54). The rest of the patients received non-invasive ventilation (n = 129), high flow nasal oxygen (n = 317), conventional oxygen therapy (n = 122), as the highest level of ventilatory support, with mortality of 50%, 39% and 22%, respectively. This is the largest COVID-19 dataset from Central-Eastern European ICUs to date. The high mortality observed especially in those receiving invasive mechanical ventilation renders the need of establishing national-international ICU registries and audits in the region that could provide high quality, transparent data, not only during the pandemic, but also on a regular basis., (© 2022. The Author(s).)

Introduction: The coronavirus SARS-CoV-2 pandemic has resulted in a large number of patients requiring intubation and prolonged mechanical ventilation. The current knowledge on the tracheotomies regarding the time form intubation, method and ventilatory parameters optimal for their performance in the mechanically ventilated patients with COVID ARDS are scarce; thus, the aim of this study is to present new data regarding their safety, adverse events and timing., Materials and Methods: This retrospective observational study is based on the data of 66 critically ill COVID patients including demographic data, timing and technique of tracheotomy, ventilatory parameters in the time of procedure, as well as complication and survival rate., Results: A number of 66 patients with COVID-related pneumonia were included in the study, among whom 32 were tracheotomized-25 patients underwent an early tracheotomy and 7 patients had late tracheotomy. The median duration of mechanical ventilation before the tracheotomy in the early group was 8 days (IQR 6-10) compared to 11 days (IQR 11-12.5.) p < 0.001) in late group. Risk of death in tracheotomy patients was significantly growing with growing level of PEEP and FiO2 at the moment of decision on tracheotomy, OR = 1.91 CI 95 (1.23;3.57); p = 0.014 and OR = 1.18 CI 95 (1.03;1.43); p = 0.048, respectively., Conclusion: Early percutaneous tracheotomy is safe (both in terms of risk of viral transmission and complication rate) and feasible in COVID-19 patients. Stability of gas exchange, and ventilatory parameters are the main prognostic factors of the outcome., (© 2022. The Author(s).)

Background: Limited evidence suggests variation in mortality of older critically ill adults across Europe. We aimed to investigate regional differences in mortality among very old ICU patients., Methods: Multilevel analysis of two international prospective cohort studies. We included patients ≥80 yr old from 322 ICUs located in 16 European countries. The primary outcome was mortality within 30 days from admission to the ICU. Results are presented as n (%) with 95% confidence intervals and odds ratios (ORs)., Results: Of 8457 patients, 2944 (36.9% [35.9-38.0%]) died within 30 days. Crude mortality rates varied widely between participating countries (from 10.1% [6.4-15.6%] to 45.1% [41.1-49.2%] in the ICU and from 21.3% [16.3-28.9%] to 55.3% [51.1-59.5%] within 30 days). After adjustment for confounding variables, the variation in 30-day mortality between countries was substantially smaller than between ICUs (median OR 1.14 vs 1.58). Healthcare expenditure per capita (OR=0.84 per $1000 [0.75-0.94]) and social health insurance framework (OR=1.43 [1.01-2.01]) were associated with ICU mortality, but the direction and magnitude of these relationships was uncertain in 30-day follow-up. Volume of admissions was associated with lower mortality both in the ICU (OR=0.81 per 1000 annual ICU admissions [0.71-0.94]) and in 30-day follow-up (OR=0.86 [0.76-0.97])., Conclusion: The apparent variation in short-term mortality rates of older adults hospitalised in ICUs across Europe can be largely attributed to differences in the clinical profile of patients admitted. The volume-outcome relationship identified in this population requires further investigation., (Copyright © 2022 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.)

Background: Brain death/death by neurologic criteria (BD/DNC) guidelines are routinely analyzed, compared and updated in the majority of countries and are later implemented as national criteria. At the same time, extensive works have been conducted in order to unify clinical procedures and to validate and implement new technologies into a panel of ancillary tests. Recently evaluated computed tomography angiography and computed tomography perfusion (CTA/CTP) seem to be superior to traditionally used digital subtraction angiography (DSA), transcranial Doppler (TCD) and cerebral perfusion scintigraphy for diagnosis of cerebral circulatory arrest (CCA). In this narrative review, we would like to demonstrate scientific evidence supporting the implementation of CTA/CTP in Polish guidelines for BD/DNC diagnosis. Research and implementation process: In the first of our base studies concerning the potential usefulness of CTA/CTP for the confirmation of CCA during BD/DNC diagnosis procedures, we showed a sensitivity of 96.3% of CTA in a group of 82 patients. CTA was validated against DSA in this report. In the second study, CTA showed a sensitivity of 86% and CTP showed a sensitivity of 100% in a group of 50 patients. In this study, CTA and CTP were validated against clinical diagnosis of BD/DNC supported by TCD. Additionally, we propose our CCA criteria for CTP test, which are based on ascertainment of cerebral blood flow (CBF) < 10 mL/100 g/min and cerebral blood volume < 1 mL/100 g in regions of interest (ROIs) localized in all brain regions. Based on our research results, CTA/CTP methods were implemented in Polish BD/DNC criteria. To our knowledge, CTP was implemented for the first time in national guidelines., Conclusions: CTA and CTP-derived CTA might be in future the tests of choice for CCA diagnosis, proper and/or Doppler pretest might significantly increase sensitivity of CTA in CCA diagnosis procedures. Whole brain CTP might be decisive in some cases of inconclusive CTA. Implementation of CTA/CTP in the Polish BD/DNC diagnosis guidelines does not show any major obstacles. We believe that in next edition of "The World Brain Death Project" CTA and CTP will be recommended as ancillary tests of choice for CCA confirmation during BD/DNC diagnosis procedures.