Nitrogen dioxide pollution increases vulnerability to COVID-19 through altered immune function.

Previous ecological studies suggest the existence of possible interplays between the exposure to air pollutants and SARS-CoV-2 infection. Confirmations at individual level, however, are lacking. To explore the relationships between previous exposure to particulate matter < 10 µm (PM10) and nitrogen dioxide (NO2), the clinical outcome following hospital admittance, and lymphocyte subsets in COVID-19 patients with pneumonia. In 147 geocoded patients, we assessed the individual exposure to PM10 and NO2 in the 2 weeks before hospital admittance. We divided subjects according to the clinical outcome (i.e., discharge at home vs in-hospital death), and explored the lymphocyte-related immune function as an index possibly affecting individual vulnerability to the infection. As compared with discharged subjects, patients who underwent in-hospital death presented neutrophilia, lymphopenia, lower number of T CD45, CD3, CD4, CD16/56 + CD3 + , and B CD19 + cells, and higher previous exposure to NO2, but not PM10. Age and previous NO2 exposure were independent predictors for mortality. NO2 concentrations were also negatively related with the number of CD45, CD3, and CD4 cells. Previous NO2 exposure is a co-factor independently affecting the mortality risk in infected individuals, through negative immune effects. Lymphopenia and altered lymphocyte subsets might precede viral infection due to nonmodifiable (i.e., age) and external (i.e., air pollution) factors. Thus, decreasing the burden of air pollutants should be a valuable primary prevention measure to reduce individual susceptibility to SARS-CoV-2 infection and mortality.

Bamlanivimab and Etesevimab administered in an outpatient setting for SARS-CoV-2 infection.

The early administration of anti-SARS-CoV-2 monoclonal antibodies (mAb) could decrease the risk of severe disease and the need of inpatients care. Herein, our clinical experience with Bamlanivimab/Etesevimab for the treatment of early SARS-CoV-2 infection through an outpatient service was described. Patients with confirmed COVID-19 were selected by General Practitioners (GPs) if eligible to mAb administration, according to manufacturer and AIFA (Agenzia-Italiana-del-Farmaco) criteria. If suitability was confirmed by the Multidisciplinary Team, the patient was evaluated within the next 48-72 hours. Then, all patients underwent a medical evaluation, followed by mAb infusion or hospitalization if the medical condition had worsened. Overall, from March 29th to June 4th, 2021, 106 patients with confirmed COVID-19 were identified by GPs; 26 were considered not eligible and then excluded, while 9 refused treatment. Among the 71 remaining, 6 were not treated because of worsening of symptoms soon after selection. Finally, 65 received mAb therapy. All treated patients survived. However, 2/65 developed adverse events (allergic reaction and atrial fibrillation, respectively) and 6/65 needed hospitalization. By performing univariate logistic regression analysis, diabetes was the only risk factor for hospitalization after mAb administration [aOR = 9.34, 95%CI = 1.31-66.49, p= .026]. Importantly, subjects who worsened awaiting mAb were more frequently obese (OR = 16.66, 95%CI = 1.80-153.9, p= .013) and received home corticosteroid therapy for COVID-19 (OR = 14.11, 95%CI = 1.53-129.6, p= .019). Establishing a network among GPs and COVID units could be an effective strategy to provide mAb treatment to patients with early SARS-CoV-2 infection to reduce hospitalizations and pressure on healthcare systems.

Management of gallstones and its related complications.

The majority of gallstone patients remain asymptomatic; however, interest toward the gallstone disease is continuing because of the high worldwide prevalence and management costs and the development of gallstone symptoms and complications. For cholesterol gallstone disease, moreover, a strong link exists between this disease and highly prevalent metabolic disorders such as obesity, dyslipidemia, type 2 diabetes, hyperinsulinemia, hypertriglyceridemia and the metabolic syndrome. Information on the natural history as well as the diagnostic, surgical (mainly laparoscopic cholecystectomy) and medical tools available to facilitate adequate management of cholelithiasis and its complications are, therefore, crucial to prevent the negative outcomes of gallstone disease. Moreover, some risk factors for gallstone disease are modifiable and some preventive strategies have become necessary to reduce the onset and the severity of complications.

Ethanol induces secretion of oxidized proteins by pancreatic acinar cells.

The pancreas is vulnerable to ethanol toxicity, but the pathogenesis of alcoholic pancreatitis is not fully defined. The intracellular oxidative balance and the characteristics of the secretion of isolated rat pancreatic acinar cells stimulated with the cholecystokinin analogue cerulein were assayed after acute oral ethanol (4 g/kg) load. Pancreatic acinar cells from ethanol-treated rats showed a significant (p < 0.02) lower content of total glutathione and protein sulfhydryls, and higher levels of oxidized glutathione (p < 0.03), malondialdehyde, and protein carbonyls (p < 0.05). Ethanol-intoxicated acinar cells showed a lower baseline amylase output compared to controls, with the difference being significantly exacerbated by cerulein stimulation. After cerulein, the release of protein carbonyls by ethanol-treated cells was significantly increased, whereas that of protein sulfhydryls was significantly decreased. In conclusion, ethanol oxidatively damages pancreatic acinar cells; cerulein stimulation is followed by a lower output of amylase and by a higher release of oxidized proteins by pancreatic acinar cells from ethanol-treated rats. These findings may account for the decreased exocrine function, intraductular plug formation, and protein precipitation in alcoholic pancreatitis.

Structural and oxidative modifications of erythrocyte ghosts in patients with primary biliary cirrhosis: relation with the disease stage and effect of bile acid treatment.

BACKGROUND: Erythrocyte membrane modifications in patients with cholestasis are supposed to reflect those of hepatocytes. METHODS: Erythrocyte membrane composition (cholesterol, phospholipids, fatty acids, protein sulphydrils and carbonyls) was assessed and related to the stage of liver disease in patients with primary biliary cirrhosis before and after 1 year of ursodeoxycholate treatment. RESULTS: Compared with controls, patients showed lower levels of protein sulphydrils (28.9 +/- 7.1 vs. 65.6 +/- 1.8 nmol mg(-1) prot) and accumulation of carbonyls (4.7 +/- 1.7 vs. 1.4 +/- 0.1 nmol mg(-1) prot). Phosphatidylethanolamine level was lower in stage III-IV cirrhosis while phosphatidylcholine and cholesterol levels were higher; as a consequence the phosphatidylcholine/sphingomyelin ratio was higher than in controls (4.25 +/- 0.55 in the I-II stage and 2.89 +/- 0.44 in the stage III-IV vs. 1.61 +/- 0.30). These changes were particularly evident in patients with more advanced stages of liver disease. Protein sulphydrils and carbonyls, phosphatidylethanolamine and cholesterol levels correlated (P<0.05) with the histological stage of the liver disease, serum and membrane cholesterol levels were significantly related (r=0.66, P<0.05). One year of ursodeoxycholate administration was accompanied by major changes of the membrane lipid composition, partial reversal of protein oxidation, and improvement of serum parameters. CONCLUSIONS: This study indicates that major alterations in protein status and lipid composition occur in erythrocyte membrane of patients with primary biliary cirrhosis. These changes were more pronounced in patients with advanced liver disease. Ursodeoxycholate was able to revert in part serum and erythrocyte alterations, especially in patients with early stages of liver disease.

Experimental observations and clinical implications of fasting and diet supplementation in fatty livers.

Fatty accumulation per se does not appear to affect liver function; however, interest has recently renewed to fatty liver because of the clinical relevance of non alcoholic steato-hepatitis (NASH) and for the increased risk of post-transplant failure in grafted livers with steatosis. Clinical and experimental studies have doubtless demonstrated that oxidative stress ensues in steatotic livers. Mitochondria represent the preferential target of the oxidative injury associated to fatty degeneration and show reduced content of glutathione, higher levels of oxidative products and damages to enzymes involved in the process of ATP synthesis, which become more evident under stressing conditions. Although obese patients with fatty liver are advantaged by weight loss, clinical and experimental observations suggest that fatty livers poorly tolerate excessive food deprivation. These observations represent the rationale for treatment strategies based on the supplementation of antioxidants and energetic substrates rather than solely a diet restriction. This review focuses on data emerging from a series of investigations performed in rats with fatty livers induced by a choline-deficient diet, which resembles human steatosis due to an excessive intake of carbohydrates, and aims to give the cue for the development of therapeutic options able to preserve hepatic function after transplantation of steatotic organs.

Adaptation of subcellular glutathione detoxification system to stress conditions in choline-deficient diet induced rat fatty liver.

The response of fatty liver to stress conditions (t-butyl hydroperoxide [t-BH] or 36 h of fasting) was investigated by assessing intracellular glutathione (GSH) compartmentation and redox status, GSH peroxidase (GSH-Px) and reductase (GSSG-Rx) activities, lipid peroxidation (TBARs) and serum ALT levels in rats on a choline-deficient diet. Baseline cytosolic GSH was similar between fatty and normal livers, while the mitochondrial GSH content was significantly lower in fatty livers. With the except of cytosolic GSH-Px activity, steatosis was associated with significantly higher GSH-related enzymes activities. Liver TBARs and serum ALT levels were also higher. Administration of t-BH significantly decreased the concentration of cytosolic GSH, increased GSSG levels in all the compartments, and increased TBARs levels in cytosol and mitochondria and serum ALT; all these alterations were more marked in rats with fatty liver. Fasting decreased the concentration of GSH in all the compartments both in normal and fatty livers, increased GSSG, TBARs and ALT levels, and decreased by 50% the activities of GSH-related enzymes. Administration of diethylmaleimide (DEM) resulted in cytosolic and microsomal GSH pool depletion. Administration of t-BH to DEM-treated rats further affected cytosolic GSH and enhanced ALT levels, whereas the application of fasting to GSH depleted rats mainly altered the mitochondrial GSH system, especially in fatty livers. This study shows that fatty livers have a weak compensation of hepatic GSH regulation, which fails under stress conditions, thus increasing the fatty liver's susceptibility to oxidative damage. Differences emerge among subcellular compartments which point to differential adaptation of these organelles to fatty degeneration.

Changes of gallbladder and gastric dynamics in patients with acute hepatitis A.

Transient alterations of gallbladder morphology and dynamics have been reported in patients with during acute hepatitis A. The presence of dyspepsia also suggests involvement of gastric motility. During a 60-day follow-up, we investigated gallbladder and gastric motility in relation to dyspepsia in acute viral hepatitis A patients. Twenty patients were assessed at referral (day 0) and at days 7, 21, 42 and 60 and compared with 20 healthy volunteers. Gallbladder morphology and motility and gastric motility were assessed in the fasting and postprandial period by functional ultrasonography using a liquid test meal. Dyspeptic symptoms were scored. At day 0, fasting gallbladder volume was 5.9 +/- 1.3 mL, 32.6 +/- 4.6 mL, and 21.5 +/- 1.9 mL (mean +/- SE) in patients with gallbladder sludge (n = 7), without sludge (n = 13) and controls, respectively (P < 0.05 in sludge vs. no sludge and controls; P < 0.05 in no sludge vs. controls, ANOVA). Small fasting gallbladder volume in patients with sludge increased and sludge disappeared within 7 days. At day 0, patients with sludge also had increased thickness of fasting gallbladder wall and increased serum transaminase levels compared with patients without sludge and controls. Gallbladder contraction was similar in patients and controls. However, patients had delayed gastric emptying, which positively correlated with dyspepsia score. Gallbladder morphological changes observed in the acute phase of hepatitis A are transient and are associated with hepatocellular damage. Gastric emptying is delayed during the first week of disease and is associated with dyspeptic symptoms.

Enhancement of gallbladder emptying in gallstone patients after oral cholestyramine.

OBJECTIVE: To evaluate whether a low dose of oral cholestyramine improves gallbladder emptying in gallstone patients. METHODS: Gallbladder volumes were assessed by sonography in 36 patients with cholesterol gallstones and 18 healthy controls. On three different days subjects ingested: 1) test meal alone, 2) test meal plus cholestyramine (4 g), and 3) cholestyramine alone (4 g). RESULTS: Fasting gallbladder volume (mean +/- SE, 25.9 +/- 1.8 ml and 19.2 +/- 1.3 ml for patients and controls, respectively, p < 0.05) and postprandial gallbladder residual volume (48.7 +/- 3.9% and 21.6 +/- 2.8% of fasting volume in patients and controls, respectively, p < 0.001) were larger in patients than controls, indicating impaired gallbladder emptying. Gallstone patients were divided into 19 "contractors" and 17 "hypocontractors" (residual gallbladder volume smaller or greater than mean +/- 2 SD of controls). Compared with the test meal alone, the addition of cholestyramine induced a further decrease of residual volume in contractors (from 30.4 +/- 2.1% to 19.8 +/- 1.9%, p < 0.001), hypocontractors (from 69.3 +/- 3.9% to 56.7 +/- 7.4%, p < 0.05), and controls (from 21.6 +/- 2.8% to 5.0 +/- 1.0%, p < 0.0004). Two hours after test meal plus cholestyramine gallbladder volume was still markedly reduced in both patients and controls. Fasting gallbladder volume 24 h after test meal plus cholestyramine was decreased in patients and in controls. The ingestion of cholestyramine alone initiated gallbladder evacuation comparable to that of test meal in both contractors and hypocontractors. CONCLUSIONS: A low dose of cholestyramine in combination with test meal induces a considerable decrement of gallbladder volume compared with test meal alone in gallstone patients. Cholestyramine alone causes a decrease of gallbladder volume which is comparable to that observed in response to test meal alone.

Fluorimetric study of intracellular Ca++ homeostasis in isolated rat pancreatic acini.

A fluorimetric method for the study of intracellular Ca++ metabolism in rat pancreatic acini is described. Following previous reports on the utilization of the new intracellularly trapped fluorescent dye fura2 in human lymphocytes, the authors point out the relevance of the cellular and fura2 concentration as critical issues for an accurate evaluation of Ca++ homeostasis. A dose-response curve to both carbamoylcholine and cholecystokinin is reported, demonstrating the ability of the cells to respond to hormonal stimulation with a transient Ca++ peak. The almost complete absence of noise in the recorded traces allow to carry out an evaluation of the intracellular mechanism related to Ca++ mobilization with a very high sensitivity.

Isolation and functional characterization of rat pancreatic acini.

The Authors describe an optimized procedure for the isolation of rat pancreatic acini and the preliminary results concerning the functional characterization of the cells. Isolation is carried out by two sequential digestive steps in a KREBS modified medium containing collagenase, separated by an intermediate step in which acini separation is fostered by incubation in a Ca++ free medium containing the Ca++ chelator EDTA. Final separation is obtained through the application of mechanical forces by aspirating the suspension in plastic pipettes. The choice of the collagenase, the duration and the entity of the mechanical dissociation strength are the main modifications to the classic procedure and allow to obtain a very high yield of cells maintaining their ability to secrete enzymes for a long period (6-7 hours). Functional characterization is completed mainly by the determination of the amylase release stimulated by increasing doses of cholecystokinin.