30 research outputs found
Usefulness of bronchoalveolar lavage in suspect COVID-19 repeatedly negative swab test and interstitial lung disease
The diagnosis of coronavirus disease 2019 (COVID-19) relies on nasopharyngeal swab, which shows a 20–30% risk of false negativity [1]. Bronchoalveolar lavage (BAL) is reported to be useful in patients with pulmonary interstitial infiltrates on high-resolution computed tomography (HRCT). We investigated the usefulness of BAL in symptomatic patients with positive HRCT and a repeatedly negative swab test (‘grey zone’)
Bile acids with differing hydrophilic-hydrophobic properties do not influence cytokine production by human monocytes and murine Kupffer cells
Bile acids have been proposed to exert immunological effects of potential pathogenic or therapeutic relevance, yet the experimental evidence remains preliminary. We reexamined the effects of a variety of bile salts with differing hydrophilic-hydrophobic properties on the production of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF alpha) from monocytes and Kupffer cells. Monocytes from healthy human donors and Kupffer cells from 5-week-old mice were incubated for up to 18 hours with or without varying concentrations of bile salts and lipopolysaccharide (LPS). Monocyte viability was greater than or equal to 95% with up to 250 mu mol/L sodium ursodeoxycholate and mu 90% with 200 mu mol/L chenodeoxycholate, decreasing sharply at higher concentrations. Kupffer cells were more vulnerable, particularly to chenodeoxycholate (viabilities of 25% and 0% at concentrations of 100 mu mol/L and 200 mu mol/L, respectively). In monocytes incubated in the presence of 20% fetal calf serum, neither ursodeoxycholate and chenodeoxycholate, nor a variety of other unconjugated and conjugated bile acids, tested up to their maximal noncytotoxic concentrations, influenced the IL-6 and TNF(alpha production, at any level of LPS stimulation. Similar to monocytes, incubation of murine Kupffer cells with ursodeoxycholate and chenodeoxycholate did not influence cytokine release. In contrast, the addition of 10 nmol/L dexamethasone to monocytes significantly decreased TNF-alpha and IL-6 release (69 +/- 11% and 48 +/- 15%, respectively). When monocytes were incubated with 200 mu mol/L chenodeoxycholate in the presence of lower concentrations of fetal calf serum (10% and 5%, respectively) a significant inhibition of cytokine release was observed, whereas incubation with ursodeoxycholate did not cause any effect. Flow cytometry using fluoresceinated LPS showed that chenodeoxycholate does not interact with the CD14 receptor, thus excluding the possibility of an interference with the LPS uptake by monocytes. Incubation with [C-14]-chenodeoxycholate showed that the intracellular bile acid uptake was inversely related to the concentration of fetal calf serum, being negligible (<3 fmol/cell) at the highest level. In conclusion, bile acids with widely different hydrophobicities are incapable of influencing the release of IL-6 and TNF alpha by monocytes and Kupffer cells, provided they are studied at noncytotoxic concentrations and in the presence of physiological amounts of proteins
Human immunodeficiency virus-induced cell death in cytokine-treated macrophages can be prevented by compounds that inhibit late stages of viral replication
The basis of the cytopathic effect induced by a laboratory strain and several clinical isolates of human immunodeficiency virus (HIV) in human macrophages cultured in the presence of macrophage colony-stimulating factor was studied. Infected macrophages die of necrosis, the consequence of the production of mature virions in infected cells. Cell death can be prevented by antiviral compounds that interfere with the assembly and budding of virions. Programmed cell death (apoptosis), a potential mechanism of HIV-mediated cell death in CD4 T lymphocytes, does not occur in infected macrophages as shown by electron microscopy, cytofluorometric and gel electrophoretic DNA analysis, and nuclear fluorescent staining by Hoechst and terminal dUTP-nick-end-labeling (TUNEL) assay. The data suggest that macrophage killing by HIV may occur in vivo. Thus, combination therapies that include compounds that inhibit the cytopathic effect of HIV in macrophages should be considered for AIDS patients
Fenoldopam and gastric tonometry during ortothopic liver transplantation
The aim of this study was to evaluate the effects of continuous infusion of fenoldopam on
splanchnic perfusion in orthotopic liver transplant (OLT) recipients.
Patients and Methods. We enrolled 40 patients of mean age 57 16 years who
underwent (OLT). They were randomly divided into two double blinded groups; continuous
fenoldopam (0.06 mcg/kg per minute) or placebo infusion. Hemodynamics, gastric
tonometry, urine output, renal function parameters, and diuretics use were collected
during selected phases of the surgery and postoperatively every 12 hours for 72 hours in the
intensive care unit.
Results. No significant differences were observed between the two groups concerning
hemodynamics, though in the fenoldopam group we observed increased splanchnic
perfusion during the whole study period but particularly after arterial unclamping
(pHi 7,31 0.04 vs 7.28 0.05; P .05) and at 48 hours after surgery (pHi 7.49 0.15 vs
7.39 0.15; P .05). Creatinine and blood urea nitrogen values were slightly higher in the
placebo group, but this data did not reach statistical significance, while higher doses of
furosemide were administered to the placebo group to maintain a urinary output over
200 mL/hour during the whole study.
Discussion. In this study we observed that continuous fenoldopam infusion (0.06 mg/kg
per minute) improved splanchnic perfusion without affecting systemic pressure.
Conclusion. Patients undergoing OLT have altered splanchnic perfusion related to
cirrhosis, surgical manipulation, and fluid shifts during and after surgery. The use of a
splanchnic vasodilator drug improved outcomes in these patients