Increase In Respiratory Rate Research Articles

Nebulised adrenaline in the post-operative management of brachycephalic obstructive airway syndrome in dogs: short-term outcomes in 90 cases (2014–2020)

ABSTRACT Case histories Medical records from a single UK-based referral hospital were retrospectively reviewed to identify brachycephalic dogs who had undergone corrective airway surgery and were nebulised with adrenaline in the post-operative period. Ninety dogs were identified between August 2014 and March 2020. Clinical findings Agitation following nebulisation with adrenaline was uncommon, with 86/90 (96%) dogs remaining calm, and overall outcome was reported as satisfactory in 68 of 73 (89%) dogs for which this information was available. Median respiratory rate at T0 (prior to first nebulisation) and T60 (1 hour following nebulisation) were both 20 breaths/minute with a median difference of 0 (95% CI = 0–0) breaths/minute (p = 0.657). Median heart rate at T0 and T60 were both 80 beats/minute with a median difference of 3 (95% CI = −10 to 7) beats/minute (p = 0.948). Two dogs experienced tachycardia, but this was not associated with the timing of administration of adrenaline. Complications reported in the 24 hours following surgery included regurgitation (n = 36), increased respiratory noise and effort (n = 10), aspiration pneumonia (n = 4), and inappetence (n = 3). A temporary tracheostomy tube was placed in 13 (14.4%) dogs. Clinical relevance Nebulisation with adrenaline is feasible, results in minimal increases in respiratory rate and heart rate and is associated with agitation in only a small number of dogs.

Controlling growth and carbohydrate utilization of tomato seedlings through day-night temperature difference and high light intensity under elevated CO2 conditions

Negative DIF, increasing nighttime temperature relative to daytime temperature, is widely used in the floral industry to reduce plant height. However, negative DIF can also reduce photosynthetic capacity in vegetative seedlings. We investigated the use of negative DIF combined with high light intensity under elevated CO2 and a long photoperiod to produce compact and well-developed tomato seedlings with reduced plant height. Seedlings were grown for 28 days under positive or negative DIF (with daytime/nighttime temperatures of 25 °C/19 °C or 21 °C/27 °C, respectively) combined with low or high light intensity [250 or 500 μmol m−2 s−1 photosynthetic photon flux density (PPFD), PPFD 250 or PPFD 500, respectively] at 1000 ppm CO2 (mean daily temperature: 23 °C across a photoperiod of 16 h d−1). Compared with positive DIF and PPFD 250, negative DIF with PPFD 500 significantly reduced plant height while tending to increase dry matter (DM) but decrease leaf area (LA). Relative growth rate was decreased under negative DIF despite the provision of PPFD 500, but there were no differences in photosynthetic rate and capacity parameters (e.g., total nitrogen and chlorophyll content at the LA level) between DIF treatments. Negative DIF and PPFD 500 might reduce DM by decreasing the amount of intercepted light in tomato seedlings. Negative DIF and PPFD 500 also increased respiration rate during nighttime and led to the consumption of more nonstructural carbohydrates (NSCs) at the LA level. Overall, our results indicate that negative DIF combined with high light intensity can maintain DM, photosynthetic capacity, and plant development while reducing plant height in tomato seedlings.

Using Recombinant Superoxide Dismutase to Control Oxidative Stress in the Gastrointestinal Tract of Cyclic Heat-Stressed Pigs.

Climate change is associated with an increased frequency and intensity of heat waves, posing a threat of heat stress to pig production. Heat stress compromises the efficiency of pig production partly due to causing oxidative stress, intestinal dysfunction, and inflammatory responses. Superoxide dismutase is an antioxidant enzyme reported to reduce oxidative stress and inflammation. Therefore, this experiment aimed to investigate whether recombinant superoxide dismutase (rSOD) could ameliorate oxidative stress and inflammatory responses in heat-stressed grower pigs. Sixty-four female pigs (Large White × Landrace, 27.8 ± 1.65 kg, mean ± SD) were randomly allocated to a control diet (standard grower feed, CON) or the control diet supplemented with 50 IU recombinant superoxide dismutase (rSOD) for 14 days. After acclimation to the diet, pigs were then housed under thermoneutral (TN, 20 °C, 35-50% relative humidity) or cyclic heat stress conditions (CHS, at 35 °C: 9 a.m. to 5 p.m. and 28 °C: 5 p.m. to 9 a.m., 35-50% relative humidity) for 3 days. Heat stress increased respiration rate (RR), skin and rectal temperature (RR and RT) (p < 0.001 for all), and reduced plasma thyroid hormone concentration (p < 0.001). The amount of oxidized glutathione (GSH:GSSG) was increased in the jejunum and ileum of CHS pigs. In the jejunum, rSOD also increased the amount of oxidized glutathione in both TN and CHS pigs, without any change in endogenous SOD activity. In the ileum, rSOD prevented increases in oxidized glutathione formation in the CHS pigs only. Taken together, this may reflect increased oxidative stress in both the jejunum and ileum in CHS pigs. Alternatively, rSOD increased the conversion of reduced to oxidized glutathione independently of CHS, possibly reflecting an increased overall SOD activity due to the addition of exogenous SOD. In conclusion, the use of in-feed SOD enzymes at a dose of 50 IU/kg may be a useful strategy for preventing oxidative stress in pigs.

The impact of antenatal and postnatal indoor air pollution or tobacco smoke exposure on lung function at 3 years in an African birth cohort.

Indoor air pollution (IAP) and tobacco smoke exposure (ETS) are global health concerns contributing to the burden of childhood respiratory disease. Studies assessing the effects of IAP and ETS in preschool children are limited. We assessed the impact of antenatal and postnatal IAP and ETS exposure on lung function in a South African birth cohort, the Drakenstein Child Health Study. Antenatally enrolled mother-child pairs were followed from birth. Lung function measurements (oscillometry, multiple breath washout and tidal breathing) were performed at 6 weeks and 3 years. Quantitative antenatal and postnatal IAP (particulate matter [PM10 ], volatile organic compounds [VOC]) and ETS exposures were measured. Linear regression models explored the effects of antenatal and postnatal exposures on lung function at 3 years. Five hundred eighty-four children had successful lung function testing, mean (SD) age of 37.3 (0.7) months. Exposure to antenatal PM10 was associated with a decreased lung clearance index (p < 0.01) and postnatally an increase in the difference between resistance at end expiration (ReE) and inspiration (p = 0.05) and decrease in tidal volume (p = 0.06). Exposure to antenatal VOC was associated with an increase in functional residual capacity (p = 0.04) and a decrease in time of expiration over total breath time (tE /tTOT ) (p = 0.03) and postnatally an increase in respiratory rate (p = 0.05). High ETS exposure postnatally was associated with an increase in ReE (p = 0.03). Antenatal and postnatal IAP and ETS exposures were associated with impairment in lung function at 3 years. Strengthened efforts to reduce IAP and ETS exposure are needed.

Effectiveness of long-term noninvasive ventilation measured by remote monitoring in neuromuscular disease.

Patients with neuromuscular disease are often treated with home noninvasive ventilation (NIV) with devices capable of remote patient monitoring. We sought to determine whether long-term NIV data could provide insight into the effectiveness of ventilation over time. We abstracted available longitudinal data for adults with neuromuscular disease in monthly increments from first available to most recent. Generalised linear mixed-effects modelling with subject-level random effects was used to evaluate trajectories over time. 1799 months of data across 85 individuals (median age 61, interquartile range (IQR) 46-71 years; 44% female; 49% amyotrophic lateral sclerosis (ALS)) were analysed, with a median (IQR) of 17 (8-35) months per individual. Over time, tidal volume increased and respiratory rate decreased. Dynamic respiratory system compliance decreased, accompanied by increased pressure support. Compared to volume-assured mode, fixed-pressure modes were associated with lower initial tidal volume, higher respiratory rate and lower pressures, which did not fully equalise with volume-assured mode over time. Compared with non-ALS patients, those with ALS had lower initial pressure support, but faster increases in pressure support over time, and ALS was associated wtih a more robust increase in respiratory rate in response to low tidal volume. Nonsurvivors did not differ from survivors in ventilatory trajectories over time, but did exhibit decreasing NIV use prior to death, in contrast with stable use in survivors. NIV keeps breathing patterns stable over time, but support needs are dynamic and influenced by diagnosis and ventilation mode. Mortality is preceded by decreased NIV use rather than inadequate support during use.

Molecular regulation of apple and grape ripening: exploring common and distinct transcriptional aspects of representative climacteric and non-climacteric fruits.

Fleshy fruits of angiosperms are organs specialized for promoting seed dispersal by attracting herbivores and enticing them to consume the organ and the contained seeds. Ripening can be broadly defined as the processes serving as a plant strategy to make the fleshy fruit appealing to animals and leads to a coordinated series of changes in color, texture, aroma and flavor, as result of an intricate interplay of genetically and epigenetically programmed events. The ripening of fruits can be categorized into two types: climacteric, which is characterized by a rapid increase in respiration rate typically accompanied by a burst of ethylene production, and non-climacteric, where this pronounced peak in respiration is absent. Here we review the most current knowledge on transcriptomic changes taking place in apple (climacteric) and grapevine (non-climacteric) fruit during ripening, with the aim to highlight specific and common hormonal and molecular events governing the process in both species. In this perspective, we found that specific NAC transcription factor members participate in the ripening initiation in grape and are involved in the attempt to restore the normal physiological ripening progression in impaired fruit ripening physiology in apple. These elements suggest the existence of a common regulatory mechanism operated by NAC transcription factors and auxin in the two species.

A History of Suicide Attempt Is Associated with Increased Sympathetic Activation in Bipolar Disorder.

Suicide risk in bipolar disorder (BD) is estimated to be up to 20 times higher than in the general population. While there is a large body of evidence suggesting that increased sympathetic activation is associated with disease and death, there is a paucity of research on the role of autonomic nervous system (ANS) dysfunction in patients with BD who have attempted suicide. Fifty-three participants with BD used a wearable device to assess the association between history of suicide attempt, current suicidal ideation, and ANS dysfunction, including measures of heart rate variability (HRV) and respiratory rate. Data were analyzed in a series of unadjusted and adjusted bivariate models of association controlling for relevant variables. A history of suicide attempts was significantly associated with an increase in respiratory rate (p < 0.01). These results remained significant after adjusting for age, BMI, and current mood state. There was no association between current suicidal ideation and heart rate or respiratory rate. In the frequency domain, HRV parameters suggest reduced parasympathetic (i.e., vagal) activity in participants with a history of suicide attempts and in those with current suicidality, suggesting changes in sympathicovagal balance in BD. Our results suggest that changes in the ANS in patients with BD and a history of suicide attempt are not restricted to pure vagally mediated HRV parameters, but rather signal a general ANS dysregulation. This ANS imbalance may be contributing to illness burden and cardiovascular disease. Further research on the relationship between ANS and suicidality in BD is needed.

Surviving heat: Resilience of Nellore bulls to solar radiation exposure

Surviving heat: Resilience of Nellore bulls to solar radiation exposure

Effects of postharvest chitosan and potassium sorbate coating on the storage quality and fungal community of fresh jujube

Fresh jujube fruit are confronted with serious quality deterioration after harvest. This study explored the effects of chitosan and potassium sorbate coatings on the physicochemical quality and fungal community of jujube during cold storage. Microscopic observation showed that chitosan can uniformly distribute potassium sorbate on the surface of jujube. Chitosan coating inhibited the increase in respiration rate and total soluble solids and the decrease in titratable acidity and firmness. Jujube fruit treated with chitosan and potassium sorbate showed the lowest decay rate (2.67%) after 35 d of storage. High-throughput sequencing analysis indicated that the largest number of fungal amplicon sequence variants (ASVs) was detected in jujube treated with chitosan and potassium sorbate, exhibiting higher Chao1, Shannon and Simpson diversity indices. Treatment with chitosan or potassium sorbate alone reduced the relative abundance of Cladosporium in jujube fruit. Jujube treated with chitosan and potassium sorbate had the lowest total relative abundance of all potential pathogenic fungi (Cladosporium, Alternaria and Diaporthe). FUNGuild analysis showed that chitosan and potassium sorbate treatment could inhibit the relative abundance of plant pathogenic fungi. As a result, chitosan maintained the physicochemical properties of jujube by inhibiting the respiration rate, and the combination of chitosan and potassium sorbate reduced the decay rate of jujube by inhibiting pathogenic fungi. Therefore, chitosan and potassium sorbate coating is a promising approach to improve the storage quality and delay the decay of jujube fruit after harvest.

Salt tolerance threshold and physiological responses in Bach Thao goats drinking diluted seawater under tropical conditions.

Climate change challenges with incremental sea level cause saltwater intrusion, which has affected the quality of freshwater and groundwater in coastal provinces, particularly the Mekong River Delta provinces of Vietnam. Interestingly, Bach Thao goats are predominant in this area and well adapted to saline water under tropical conditions. Therefore, this study investigated the salt tolerance threshold of Bach Thao goats drinking diluted seawater (DSW). The experiment was performed using seven Bach Thao male goats (20.60 ± 1.12 kg) and divided into two phases. In Phase 1 (control, C), all goats were provided fresh water (FW) for 7 days from two identical buckets, and daily water intake (WI) was recorded from both buckets. In Phase 2 (preference test, PT), each goat was provided FW from the first bucket and DSW from the second bucket or vice versa. The concentration of DSW for the preference test was 0.5%-2.0%. Body weight and dry matter intake showed no differences according to DSW consumption; however, WI was significantly lower during Phase 2 (p < 0.05), which was due to the lower WI with 1.5% and 2% of DSW (p < 0.05). Goats showed a similar preference for fluid intake between FW and DSW at 0.0%-1.0% levels and began avoiding DSW at 1.5% and rejected at 2.0% of DSW. Goats consuming 1.5% of DSW showed increased respiration rate from 13:00 to 19:00 h and rectal temperature at 13:00 h (p < 0.05). Goats can tolerate up to 1.0% of DSW. Shifting to FW activated aversive drinking to 1.5% and 2.0% of DSW. This behavioral response was prominent at 0.5% DSW. Moreover, goats that drank 1.5% of DSW had decreased thermoregulation.

Nitrogen addition increases mass loss of gymnosperm but not of angiosperm deadwood without changing microbial communities

Enhanced nitrogen (N) deposition due to combustion of fossil fuels and agricultural fertilization is a global phenomenon which has severely altered carbon (C) and N cycling in temperate forest ecosystems in the northern hemisphere. Although deadwood holds a substantial amount of C in forest ecosystems and thus plays a crucial role in nutrient cycling, the effect of increased N deposition on microbial processes and communities, wood chemical traits and deadwood mass loss remains unclear. Here, we simulated high N deposition rates by adding reactive N in form of ammonium-nitrate (40 kg N ha−1 yr−1) to deadwood of 13 temperate tree species over nine years in a field experiment in Germany. Non-treated deadwood from the same logs served as control with background N deposition. Our results show that chronically elevated N levels alters deadwood mass loss alongside respiration, enzymatic activities and wood chemistry depending on tree clade and species. In gymnosperm deadwood, elevated N increased mass loss by +38 %, respiration by +37 % and increased laccase activity 12-fold alongside increases of white-rot fungal abundance +89 % (p = 0.03). Furthermore, we observed marginally significant (p = 0.06) shifts of bacterial communities in gymnosperm deadwood. In angiosperm deadwood, we did not detect consistent effects on mass loss, physico-chemical properties, extracellular enzymatic activity or changes in microbial communities except for changes in abundance of 10 fungal OTUs in seven tree species and 28 bacterial OTUs in 10 tree species. We conclude that N deposition alters decomposition processes exclusively in N limited gymnosperm deadwood in the long term by enhancing fungal activity as expressed by increases in respiration rate and extracellular enzyme activity with minor shifts in decomposing microbial communities. By contrast, deadwood of angiosperm tree species had higher N concentrations and mass loss as well as community composition did not respond to N addition.

PD-L1 Positron Emission Tomography Imaging in Patients With Non-Small Cell Lung Cancer: Preliminary Results of the ImmunoPET Phase 0 Study

ImmunoPET is a multicenter, single arm, phase 0-1 study of 89Zr-DFO-Sq-durvalumab (89Zr-durvalumab), a novel PET tracer, designed to interrogate the expression of PD-L1 in patients with NSCLC. Clinically relevant findings from phase 0 are presented here. Phase 0 was designed to investigate tracer biodistribution and safety in patients with metastatic NSCLC with PD-L1 expression >25%. After 60MBq/70kg 89Zr-durvalumab infusion, PET/CT images were acquired at days 0, 1, 3 or 5 ± 24h. Baseline FDG PET/CT was performed prior to PD-L1 PET imaging. All five patients recruited to phase 0 completed the full imaging protocol. The only reported adverse event was a transient asymptomatic increase in respiratory rate. At the time of PD-L1 imaging, two patients were in complete remission on FDG-PET after treatment with osimertinib and pembrolizumab; neither showed PD-L1 tracer uptake in previous tumor sites. All three patients with active tumor had received radiotherapy to some or all disease sites prior to PD-L1 imaging. With the exception of a single disease site, specific uptake of 89Zr-durvalumab uptake was seen in tumours, with increasing uptake in tumor seen up to Day 5 post-injection. Patient 1, who had multiple metastases, including brain and bone, showed more intense 89Zr-durvalumab uptake in recently irradiated bone lesions than un-irradiated lesions and uptake was also observed in treated brain metastases.. One patient, who experienced rapid growth of a single lung lesion that had acquired resistance to pembrolizumab, showed no significant 89Zr-durvalumab in that lesion, despite recent radiotherapy. In patient 5, 89Zr-durvalumab uptake was observed in the viable rim of a large, recently irradiated adrenal oligometastasis. 89Zr- durvalumab imaging was safe and detected known viable tumor at multiple sites. Recently irradiated tumours showed the highest uptake and in another, a single site of immunotherapy resistant disease showed minimal tracer uptake. PD-L1 imaging may have utility in patients with NSCLC treated with radiotherapy.

The Efficacy of Nebulized Epinephrine in Children with Acute Asthma: A Randomized Double-blind Trial

Introduction: Countries like Bangladesh have seen an increase in the prevalence of bronchial asthma. The goal of the study was to compare the efficacy of nebulized salbutamol and nebulized epinephrine in treating children with acute asthma. Objectives: To assess the clinical improvement of acute bronchial asthma in children following nebulization with salbutamol and epinephrine. Methodology: This random, double-blind clinical trial was conducted in the paediatric department of the Mymensingh Medical College Hospital. Children of either sex with clinical features of acute exacerbation of asthma, an asthma score &gt;5 to 11, an age range from 6 to 12 years, and the ability to measure peak expiratory flow rate (PEFR) were enrolled in this study. Outcomes were observed by measuring PEFR, respiratory rate, pulse rate, and SaO2 and also by determining asthma scores at 15, 35, 55, and 90 min after nebulization at a regular interval at 0, 20, 40, and 60 min. Differences from the base line and differences between both groups were observed. Results: A total of 56 patients with acute asthma were enrolled in this study. Among them, 27 children were in the salbutamol group, and 29 patients were in the epinephrine group. Among baseline characteristics, there was no statistically significant difference (p &gt; 0.05) between the two groups. Asthma score and respiratory rate decreased more in the salbutamol group with time after nebulization, but no statistically significant differences existed for the follow-up at 15, 35, and 55 minutes. A statistically significant increase in asthma score and respiratory rate was seen at 90 minutes of treatment in the salbutamol group. On the other hand, percent of predicted PEFR and SpO2 increased with time in both groups, and no statistically significant differences existed except for SpO2 at 35 min of follow-up in the salbutamol group. The epinephrine-treated group had a higher incidence of side effects as compared with the salbutamol group, but there was no statistically significant difference. Conclusion: Based on this study, in the treatment of asthmatic children with a mild to moderate exacerbation, both nebulized epinephrine and nebulized salbutamol were effective when given in addition to oral steroids.

Effects of postharvest gamma irradiation on quality maintenance of Cara Cara navel orange (Citrus sinensis L. Osbeck) during storage

Gamma irradiation is a non-thermal treatment to effectively eliminate pathogenic microorganisms in citrus production. Here, Cara Cara fruit samples were treated with gamma irradiation (0.3, 0.6, and 0.9 kGy), then their physicochemical quality and antioxidant ability were evaluated for a period of 70 days (d). The irradiated fruit exhibited increases in respiration rate with irradiation dose in the storage period of 0–56 d. During early shelf life (0–42 d), the decay rate of irradiated fruit (0–22%) was higher than that of the control (0–6%) in a dose-dependent manner; while in later shelf life, 0.3 and 0.6 kGy irradiation resulted in lower decay rates. The irradiation showed no significant effect on titratable acidity and total organic acids during storage. Irradiation at 0.6 kGy reduced free sugar content and TSS value, while increased the total phenolic content, DPPH and ABTS values of the fruit at most sampling time points. Considering the reduction of decay rate, respiratory intensity, and weight loss of the fruit under 0.6 kGy irradiation during 56–70 d of storage, 0.6 kGy may be an appropriate radiation dose to maintain the shelf-life quality of Cara Cara fruit, particularly for prolonged postharvest storage.

Effect of Ambulatory Oxygen on the Respiratory Pattern during the 6 Min Walking Test in Patients with Interstitial Lung Diseases.

Patients with pulmonary fibrosis experience early oxyhemoglobin desaturation under effort, which limits their ability to exercise and their quality of life. Recent studies have shown that in resting normoxaemic patients who become hypoxemic under exertion, administration of outpatient oxygen significantly improves stress dyspnoea and quality of life. It is unclear how this happens, since oxygen administration does not act directly on dyspnoea, and does not appear to have much effect on the heart rate and pulmonary artery pressure. We tested the hypothesis that correcting the hypoxaemia could reduce the increase in respiratory effort during the 6 min walking test, recording the breathing pattern during administration of oxygen or placebo. We evaluated 20 patients with fibrotic interstitial lung diseases (17 males and 3 females; mean age 72 ± 2 years; M ± SE) with a resting SpO2 ≥92 that fell to ≤88% during the 6 min walk test (6MWT). After first establishing the oxygen flow necessary to prevent desaturation, the patients underwent two further 6MWT, 15-20 min apart, one with administration of medical air and one with oxygen at the same flow, in randomized double-blind order. During the test, SpO2, heart rate, respiratory rate, tidal volume and minute ventilation (VE) were recorded, using a Spiropalm spirometer (Cosmed, Rome, Italy). Oxygen saturation during the 6MWT decreased to a minimum value of 82.3% (95% CI 80.1-84.5%) during placebo and to 92% (90.3-93.7%) during oxygen with an average difference of 9.7% (7.8-11.6%, p < 0.0001). On the contrary, heart rate showed an increasing trend with walking time reaching a significantly higher maximum rate during placebo, with a difference of 5.4 bpm (2.9-8.7, p < 0.005) compared to oxygen. The distance walked was slightly but significantly greater after oxygen by 28 m (2-53, p < 0.05) and end of test dyspnoea after placebo by 0.6 points (0.1-1.1, p < 0.05). Respiratory rate increased over time, without differences between oxygen and placebo in the first minute of walking, then increasing significantly more during placebo (p < 0.0005). With placebo, tidal volume increased rapidly reaching a plateau at about 48% of FVC after 3 min, while with oxygen, the increase was slower, reaching a maximum of about 45% of FVC at the end of the test. Nevertheless, the difference was highly significant (p < 0.0005) at all the time points. Minute ventilation also increased significantly with walking time but remained at a highly significant lower level during oxygen than placebo at all the time points. Mean reduction in VE during the test with oxygen compared to placebo was 4.4 L/min (3.9-4.9, p < 0.0005). In our ILD patients, administration of outpatient oxygen during walking was related to a reduced increase in heart rate, respiratory rate, tidal volume and minute ventilation necessary to meet increased oxygen requirements, resulting in a lower workload on the cardiovascular system and on respiratory muscles and a consequent reduction in dyspnoea.

The roles of carbonate, borate, and bicarbonate ions in affecting zooplankton hatching success under ocean acidification

Two ocean acidification studies about egg hatching success (HS) in geographically important marine copepods, Calanus finmarchicus and C. helgolandicus, were reanalyzed with improved statistical procedures. The new results at low and moderate levels of seawater acidification showed no HS inhibition at normal habitat temperatures but statistically significant inhibition at warmer and colder temperatures. These HS results were compared with seawater carbonate system and borate concentrations from precise seawater measurements. The temperature dependent differences in HS could not be directly explained by changes in the seawater concentrations of either H+, bicarbonate (HCO3−), or CO2* (CO2* being the sum of unhydrated CO2 and H2CO3). In contrast, HS differences did match trends in seawater carbonate (CO32−) concentrations. A numerical model was developed which evaluates the concentrations of O2 or CO2*, HCO3−, and CO32− at the cellular level across an egg and embryo by considering both gas diffusion with the seawater and respiration by the embryo. Again, temperature-dependent trends in HS could not be explained changes in intracellular CO2* or HCO3− concentrations, but HS did trend with the changes in intracellular CO32− concentrations. Carbonate ions form strong coordination complexes with metals, so acidification-driven decreases in external seawater carbonate concentrations, which are amplified at warmer temperatures, could release injurious metals, thus driving the HS inhibition at warmer temperatures. Increases in cytoplasmic carbonate concentrations at warmer temperatures caused by seawater acidification could complex with biochemically-needed nutrient-type metals within the cells, also causing the increased HS inhibition at warmer temperatures. Furthermore, boron is essential in chemically signaling within and between cells. Seawater borate concentrations were closely correlated with HS inhibition via Michaelis-Menton equations, suggesting that acidification-driven decreases in seawater borate concentrations may also inhibit HS. Finally, the acidification-driven increases in CO2 diffusion into cells dramatically increased intracellular bicarbonate concentrations. At mild levels of seawater acidification, an organism might compensate by exporting bicarbonate from the cells to the haemolymph and then to the seawater. Although the energetic cost, as percentage of ATP production, might be high, increased respiration rates at warmer temperatures might better allow the organism to survive. However, as temperature is lowered, the cellular respiration rate declines more rapidly with respect to temperature than does the gas diffusion coefficient. Consequently, bicarbonate accumulation driven by inward CO2 diffusion might overwhelm the egg's bicarbonate export capacity at colder temperatures, explaining the colder temperature HS inhibition.

Effects of the Use of N95 Masks on the Vital Signs of Healthy Healthcare Workers During the COVID-19 Pandemic: A Hospital-Based Cross-Sectional Study.

The N95 filtering facepiece respirator (FR) is the most commonly recommended respiratory protection used in healthcare settings. However, concerns have been raised about its use because it can increase respiratory resistance and dead space. The primary objective of this study was to determine the effect of wearing N95 masks on the vital signs, i.e., oxygen saturation, pulse rate, and respiratory rate, of the participant health workers. Our secondary objective was to assess the subjective feeling of discomfort when wearing N95 masks. The study participants were healthy healthcare workers taking care of coronavirus disease 2019 (COVID-19)-infected pediatric cases who did at least six hours of continuous shift duty in the pediatric COVID-19 ward at a tertiary care hospital in the eastern part of India. They were evaluated for vital signs at various time intervals while wearing N95 masks. Subjective discomfort at any point in time was also noted. We found a significant variation in the mean oxygen saturation (SpO2) and heart rate (HR) reduction across the four different points. The pair-wise comparison showed a small but significant decrease in the mean SpO2 of 98.3% (1.1)at six hoursas compared with a mean SpO2 of 98.7% (0.9) at three hours. Similarly, a significant increase was noted for a mean HR of 84.7bpm (11.2) at six hours compared with a baseline of 82.3bpm (9.2) and 83.2bpm (8.8) at three hours. The continuous use of an N95 mask leads to a mild increase in respiratory rate. However, heart rate and oxygen saturation vary significantly at different points in time after N95 mask use.

Chronic pulmonary fibrosis alters the functioning of the respiratory neural network.

Some patients with idiopathic pulmonary fibrosis present impaired ventilatory variables characterised by low forced vital capacity values associated with an increase in respiratory rate and a decrease in tidal volume which could be related to the increased pulmonary stiffness. The lung stiffness observed in pulmonary fibrosis may also have an effect on the functioning of the brainstem respiratory neural network, which could ultimately reinforce or accentuate ventilatory alterations. To this end, we sought to uncover the consequences of pulmonary fibrosis on ventilatory variables and how the modification of pulmonary rigidity could influence the functioning of the respiratory neuronal network. In a mouse model of pulmonary fibrosis obtained by 6 repeated intratracheal instillations of bleomycin (BLM), we first observed an increase in minute ventilation characterised by an increase in respiratory rate and tidal volume, a desaturation and a decrease in lung compliance. The changes in these ventilatory variables were correlated with the severity of the lung injury. The impact of lung fibrosis was also evaluated on the functioning of the medullary areas involved in the elaboration of the central respiratory drive. Thus, BLM-induced pulmonary fibrosis led to a change in the long-term activity of the medullary neuronal respiratory network, especially at the level of the nucleus of the solitary tract, the first central relay of the peripheral afferents, and the Pre-Bötzinger complex, the inspiratory rhythm generator. Our results showed that pulmonary fibrosis induced modifications not only of pulmonary architecture but also of central control of the respiratory neural network.

Clinical features and risk factors of adverse clinical outcomes in central pulmonary embolism using machine learning analysis

BackgroundIn prior studies, central pulmonary embolism (PE) was associated with high clot burden and was considered an independent predictor for thrombolysis. Further information about predictors of adverse outcomes in these patients is needed for better risk stratification. The objective is to describe independent predictors of adverse clinical outcomes in patients with central PE. MethodsLarge retrospective, observational, and single-center study of hospitalized patients with central PE. Data were gathered on demographics, comorbidities, clinical features on admission, imaging, treatments, and outcomes. Multivariable standard and Least Absolute Shrinkage and Selection Operator (LASSO) machine learning logistic regressions and sensitivity analyses were used to analyze factors associated with a composite of adverse clinical outcomes, including vasopressor use, mechanical ventilation, and inpatient mortality. ResultsA total of 654 patients had central PE. The mean age was 63.1 years, 59% were women, and 82% were African American. The composite adverse outcome was observed in 18% (n = 115) of patients. Serum creatinine elevation (odds ratio [OR] = 1.37, 95% CI = 1.20–1.57; p = 0.0001), white blood cell (WBC) count elevation (OR = 1.10, 95% CI = 1.05–1.15; p < 0.001), higher simplified pulmonary embolism severity index (sPESI) score (OR = 1.47, 95% CI = 1.18–1.84; p = 0.001), serum troponin elevation (OR = 1.26, 95% CI 1.02–1.56; p = 0.03), and respiratory rate increase (OR = 1.03, 95% CI = 1.0–1.05; p = 0.02) were independent predictors of adverse clinical outcomes. ConclusionAmong patients with central PE, higher sPESI score, WBC count elevation, serum creatinine elevation, serum troponin elevation, and respiratory rate increase were independent predictors of adverse clinical outcomes. Right ventricular dysfunction on imaging and saddle PE location did not predict adverse outcomes.

Long-term successive rotation affects soil microbial resource limitation and carbon use efficiency in Chinese fir (Cunninghamia lanceolata) monoculture plantations

Long-term successive rotation has resulted in negative effects on stand productivity, soil nutrient pool and microbial diversity and function in monoculture tree plantations. However, how successive rotation influences soil microbial nutrient limitation and carbon use efficiency (CUE) and their linkage with resource carbon (C): nitrogen (N): phosphorus (P) stoichiometry remain largely unknown. To solve this puzzle, we compared the C:N:P stoichiometries of leaf litter, fine root and soil, as well as microbial biomass and enzyme activities among three Chinese fir (Cunninghamia lanceolata) plantations with first (FRP), second (SRP) and third (TRP) generations and a natural broad-leaved forest (BL). We found that long-term successive rotation of Chinese fir decreased litter biomass by 64.7% ∼ 80.9% and enhanced litter C:N ratio by 2.7% ∼ 36.0% compared to the BL. Successive rotation decreased the contents of dissolved organic C, total N, and soil C:P and N:P ratios, and resulted in an increased C:N imbalance between soil microorganisms and nutrients in the TRP generation. Long-term successive rotation increased microbial C limitation by 1.5% ∼ 11.1% but decreased N and P limitations by 127.3% ∼ 160.9% and 15.3% ∼ 37.5%, compared with the BL, and resulted in significant increases in microbial CUE and substrate-induced respiration rate of C to N sources in the TRP generation. Structural equation modeling suggested that successive rotation indirectly affected microbial CUE and SIR by changing litter C:N, enzyme C:N and soil C:N imbalance. Collectively, these findings indicated that long-term successive rotation aggravated soil microbial C (energy) limitation and affected microbial CUE and capacity due to the increased stoichiometric imbalance between their resources. Future management practices that could increase litter and soil quality could be helpful to decrease microbial C limitation and maintain microbial functionality for sustainable monoculture plantations.