Influence of Carbon Agglomerate Formation on Micropollutants Removal in Combined PAC-Membrane Filtration Processes for Advanced Wastewater Treatment

Micropollutants (MPs) are ubiquitous in wastewater and are not effectively removed by the existing conventional treatment processes, resulting in increased environmental pollution. Nowadays, dosing of powdered activated carbon (PAC) prior to membrane filtration has emerged as an advanced wastewater treatment method for MPs removal. This study investigated the carbon agglomerate formation in the PAC stock suspension and its influence on MPs removal in PAC-capillary membrane filtration processes at both lab- and pilot-scale levels. Both lab- and pilot-scale membrane filtration results revealed that MPs removal efficiency is affected with the increase of PAC concentration in the stock suspension. For example, one of the investigated pilot tests showed a significantly reduced removal of good adsorbable MPs (from 57 to 17%) when stock suspension concentration was increased from 0.2 to 20 g/L. It is assumed that PAC agglomerates led to a slower adsorption kinetic and an inhomogeneous distribution of PAC in the membrane system. Maintaining PAC concentration in the stock suspension as low as possible (below 0.2 g/L for investigated PAC) certainly would help to avoid agglomeration problems and enhance the overall performance of the processes.

Bronco T (Shirisadi kasaya), a polyherbal formulation ameliorates LPS induced septicemia in rats

Septicemia is a life-threatening state, leading to multi-organ failure, ARDS and death. So, efforts are being made to identify novel therapies. Here, Bronco T (BT), a polyherbal formulation developed in 1984 for treating asthma, has been repurposed against septicemia induced ALI. The LPS (3mg/kg BW) was injected intraperitoneally before 24 hours, of surgery to assess the cardiorespiratory parameters, blood PaO2/FiO2, pulmonary water content and histological changes in the lungs. The pentoxifylline (PTX) (25 mg/kg b.w.) was used as the positive control. The PTX was given one hour before LPS and BT was given 3 hours (orally in different doses of 3, 1.5 and 0.75 gm/kg BW) to maintain the Cmax of the drug. The LPS treated group showed significant bradypnea, bradycardia and low heart rate frequency as observed, through elongated peaks (RR) and (MAP) respectively and finally death after 95 minutes of LPS injection. The PTX and BT (3gm/kg) pretreatment significantly prevented these changes (dose-dependent in the BT group). The survival was maintained up to 190 min after LPS. The Pentoxifylline showed a better response (75%) than Bronco T (72%). In both the treatments, a significant decrease in pulmonary water content and minimal neutrophil infiltration and intact alveoli-capillary membrane was seen in the transverse section (T.S) of the lungs. Conclusion: Significant improvement was noted in survival time, lesser tissue damage and better lung physiology by treating with Bronco T in LPS induced septicemia.

Alveolar Nitric Oxide as a Biomarker of COVID-19 Lung Sequelae: A Pivotal Study

Since SARS-CoV-2 emerged in 2019, strict monitoring of post-COVID-19 patients in order to ensure the early detection of sequelae and/or chronic organ damage that could been associated with the infection has been essential. Potential involvement of the NO pathway in the development of post-COVID-19 lung fibrotic alterations is feasible, since the majority of respiratory cells can produce NO, and fractional exhaled NO (FeNO) represents a biomarker of airway inflammation. The aim of this study was to investigate the potential utility of multiple-flow FeNO parameters in a post-COVID-19 population and to compare it with other indicators of lung damage proposed in the literature. We enrolled 20 patients hospitalized for COVID-19, who underwent clinical, respiratory functional (including PFTs and FeNO) and radiological follow-up after discharge. Compared with age- and sex-matched healthy controls, post-COVID-19 patients showed significantly higher FeNO 350 mL/s and CaNO levels. Moreover, among the parameters included in the follow-up, CaNO showed the best accuracy in indicating predominant fibrotic changes and GGO at CT scan. To our knowledge, this preliminary study has investigated for the first time multiple-flow FeNO parameters in a post-COVID-19 population. The evidence of increased CaNO values may imply the persistence of alveolar and bronchiolar inflammation and/or a mild impairment of the alveolar-capillary membrane in these patients.

Simultaneous Measurement of Lung Diffusing Capacity and Pulmonary Hemodynamics Reveals Exertional Alveolar‐Capillary Dysfunction in Heart Failure With Preserved Ejection Fraction

Background Hemodynamic perturbations in heart failure with preserved ejection fraction (HFpEF) may alter the distribution of blood in the lungs, impair gas transfer from the alveoli into the pulmonary capillaries, and reduce lung diffusing capacity. We hypothesized that impairments in lung diffusing capacity for carbon monoxide (DL CO ) in HFpEF would be associated with high mean pulmonary capillary wedge pressures during exercise. Methods and Results Rebreathe DL CO and invasive hemodynamics were measured simultaneously during exercise in patients with exertional dyspnea. Pulmonary pressure waveforms and breath‐by‐breath pulmonary gas exchange were recorded at rest, 20 W, and symptom‐limited maximal exercise. Patients with HFpEF (n=20; 15 women, aged 65±11 years, body mass index 36±8 kg/m 2 ) achieved a lower symptom‐limited maximal workload (52±27 W versus 106±42 W) compared with controls with noncardiac dyspnea (n=10; 7 women, aged 55±10 years, body mass index 30±5 kg/m 2 ). DL CO was lower in patients with HFpEF compared with controls at rest (DL CO 10.4±2.9 mL/min per mm Hg versus 16.4±6.9 mL/min per mm Hg, P <0.01) and symptom‐limited maximal exercise (DL CO 14.6±4.7 mL/min per mm Hg versus 23.8±10.8 mL/min per mm Hg, P <0.01) because of a lower alveolar‐capillary membrane conductance in HFpEF (rest 16.8±6.6 mL/min per mm Hg versus 28.4±11.8 mL/min per mm Hg, P <0.01; symptom‐limited maximal exercise 25.0±6.7 mL/min per mm Hg versus 45.5±22.2 mL/min per mm Hg, P <0.01). DL CO was lower in HFpEF for a given mean pulmonary artery pressure, mean pulmonary capillary wedge pressure, pulmonary arterial compliance, and transpulmonary gradient. Conclusions Lung diffusing capacity is lower at rest and during exercise in HFpEF due to impaired gas conductance across the alveolar‐capillary membrane. DL CO is impaired for a given pulmonary capillary wedge pressure and pulmonary arterial compliance. These data provide new insight into the complex relationships between hemodynamic perturbations and gas exchange abnormalities in HFpEF.

Ultrasound and Microbubbles for Targeted Drug Delivery to the Lung Endothelium in ARDS: Cellular Mechanisms and Therapeutic Opportunities

Acute respiratory distress syndrome (ARDS) is characterized by increased permeability of the alveolar–capillary membrane, a thin barrier composed of adjacent monolayers of alveolar epithelial and lung microvascular endothelial cells. This results in pulmonary edema and severe hypoxemia and is a common cause of death after both viral (e.g., SARS-CoV-2) and bacterial pneumonia. The involvement of the lung in ARDS is notoriously heterogeneous, with consolidated and edematous lung abutting aerated, less injured regions. This makes treatment difficult, as most therapeutic approaches preferentially affect the normal lung regions or are distributed indiscriminately to other organs. In this review, we describe the use of thoracic ultrasound and microbubbles (USMB) to deliver therapeutic cargo (drugs, genes) preferentially to severely injured areas of the lung and in particular to the lung endothelium. While USMB has been explored in other organs, it has been under-appreciated in the treatment of lung injury since ultrasound energy is scattered by air. However, this limitation can be harnessed to direct therapy specifically to severely injured lungs. We explore the cellular mechanisms governing USMB and describe various permutations of cargo administration. Lastly, we discuss both the challenges and potential opportunities presented by USMB in the lung as a tool for both therapy and research.

REGULATION OF BREATHING IN A WIDE RANGE OF PHYSICAL ACTIVITIES

In modern physiology, very simplified perceptions of such an essential system for the body as the respiratory system have taken root. The system analysis showed that at a physical load of more than 50 W, the tissue respiratory subsystem is activated, providing a volume blood flow rate adequate to the amount of oxygen consumed, and in the external respiratory subsystem the regulation on oxygen voltage in arterial blood is activated, and the regulation on carbon dioxide voltage is deactivated. The role of respiratory frequency in increasing the rate of diffusion through the alveolar capillary membrane is shown. For physiologists, medical professionals and trainers.