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Clinical and Molecular Hepatology Jan 2023The development of refractory ascites in approximately 10% of patients with decompensated cirrhosis heralds the progression to a more advanced stage of cirrhosis. Its... (Review)
Review
The development of refractory ascites in approximately 10% of patients with decompensated cirrhosis heralds the progression to a more advanced stage of cirrhosis. Its pathogenesis is related to significant hemodynamic changes, initiated by portal hypertension, but ultimately leading to renal hypoperfusion and avid sodium retention. Inflammation can also contribute to the pathogenesis of refractory ascites by causing portal microthrombi, perpetuating the portal hypertension. Many complications accompany the development of refractory ascites, but renal dysfunction is most common. Management starts with continuation of sodium restriction, which needs frequent reviews for adherence; and regular large volume paracentesis of 5 L or more with albumin infusions to prevent the development of paracentesisinduced circulatory dysfunction. Albumin infusions independent of paracentesis may have a role in the management of these patients. The insertion of a covered, smaller diameter, transjugular intrahepatic porto-systemic stent shunt (TIPS) in the appropriate patients with reasonable liver reserve can bring about improvement in quality of life and improved survival after ascites clearance. Devices such as an automated low-flow ascites pump may be available in the future for ascites treatment. Patients with refractory ascites should be referred for liver transplant, as their prognosis is poor. In patients with refractory ascites and concomitant chronic kidney disease of more than stage 3b, assessment should be referred for dual liver-kidney transplants. In patients with very advanced cirrhosis not suitable for any definitive treatment for ascites control, palliative care should be involved to improve the quality of life of these patients.
Topics: Humans; Ascites; Quality of Life; Liver Cirrhosis; Albumins; Hypertension, Portal; Sodium; Portasystemic Shunt, Transjugular Intrahepatic; Paracentesis
PubMed: 35676862
DOI: 10.3350/cmh.2022.0104 -
Alzheimer's Research & Therapy Jan 2021Alzheimer's disease (AD) is an intractable neurodegenerative disorder in the elderly population, currently lacking a cure. Trichostatin A (TSA), a histone deacetylase...
BACKGROUND
Alzheimer's disease (AD) is an intractable neurodegenerative disorder in the elderly population, currently lacking a cure. Trichostatin A (TSA), a histone deacetylase inhibitor, showed some neuroprotective roles, but its pathology-improvement effects in AD are still uncertain, and the underlying mechanisms remain to be elucidated. The present study aims to examine the anti-AD effects of TSA, particularly investigating its underlying cellular and molecular mechanisms.
METHODS
Novel object recognition and Morris water maze tests were used to evaluate the memory-ameliorating effects of TSA in APP/PS1 transgenic mice. Immunofluorescence, Western blotting, Simoa assay, and transmission electron microscopy were utilized to examine the pathology-improvement effects of TSA. Microglial activity was assessed by Western blotting and transwell migration assay. Protein-protein interactions were analyzed by co-immunoprecipitation and LC-MS/MS.
RESULTS
TSA treatment not only reduced amyloid β (Aβ) plaques and soluble Aβ oligomers in the brain, but also effectively improved learning and memory behaviors of APP/PS1 mice. In vitro study suggested that the improvement of Aβ pathology by TSA was attributed to the enhancement of Aβ clearance, mainly by the phagocytosis of microglia, and the endocytosis and transport of microvascular endothelial cells. Notably, a meaningful discovery in the study was that TSA dramatically upregulated the expression level of albumin in cell culture, by which TSA inhibited Aβ aggregation and promoted the phagocytosis of Aβ oligomers.
CONCLUSIONS
These findings provide a new insight into the pathogenesis of AD and suggest TSA as a novel promising candidate for the AD treatment.
Topics: Aged; Albumins; Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Chromatography, Liquid; Cognition; Disease Models, Animal; Endothelial Cells; Humans; Hydroxamic Acids; Mice; Mice, Transgenic; Presenilin-1; Tandem Mass Spectrometry
PubMed: 33397436
DOI: 10.1186/s13195-020-00746-8 -
Journal of Nuclear Medicine : Official... Jun 2022Fibroblast activation protein (FAP) has become an attractive target for diagnosis and therapy, and a series of FAP inhibitor (FAPI)-based radiotracers has been developed...
Fibroblast activation protein (FAP) has become an attractive target for diagnosis and therapy, and a series of FAP inhibitor (FAPI)-based radiotracers has been developed and had excellent performance for diagnosis outcomes in clinical applications. Yet, their fast clearance and insufficient tumor retention have hampered their further clinical application in cancer treatment. In this study, we developed 2 albumin binder-conjugated FAPI radiotracers, TEFAPI-06 and TEFAPI-07. They were derived from FAPI-04 and were optimized by conjugating 2 types of well-studied albumin binders, 4-(-iodophenyl) butyric acid moiety (TEFAPI-06) and truncated Evans blue moiety (TEFAPI-07), to try to overcome the above limitations at the expense of prolonging the blood circulation. TEFAPI-06 and TEFAPI-07 were synthesized and labeled with Ga, Y, and Lu successfully. A series of cell assays was performed to identify the binding affinity and FAP specificity in vitro. PET imaging, SPECT imaging, and biodistribution studies were performed to evaluate the pharmacokinetics in pancreatic cancer patient-derived xenograft (PDX) animal models. The cancer treatment efficacy of Lu-TEFAPI-06 and Lu-TEFAPI-07 were evaluated in pancreatic cancer PDX-bearing mice. The binding affinities (dissociation constants) to FAP of Ga-TEFAPI-06 and Ga-TEFAPI-07 were 10.16 ± 2.56 nM and 7.81 ± 2.28 nM, respectively, which were comparable with that of Ga-FAPI-04. Comparative PET imaging of HT-1080-FAP and HT-1080 tumor-bearing mice and a blocking study showed the FAP-targeting ability in vivo of these 2 tracers. Compared with Lu-FAPI-04, PET imaging, SPECT imaging, and biodistribution studies of TEFAPI-06 and TEFAPI-07 demonstrated their remarkably enhanced tumor accumulation and retention, respectively. Notable tumor growth inhibition by Lu-TEFAPI-06 and Lu-TEFAPI-07 were observed, whereas the control group and the group treated by Lu-FAPI-04 showed a slight therapeutic effect. Two albumin binder-conjugated FAPI radiopharmaceuticals have been developed and evaluated in vitro and in vivo. Significantly improved tumor uptake and retention were observed, compared with the original FAPI tracer. Both Lu-TEFAPI-06 and Lu-TEFAPI-07 showed remarkable growth inhibition of PDX tumors, whereas the side effects were almost negligible, demonstrating that these radiopharmaceuticals are promising for further clinical translational studies.
Topics: Albumins; Animals; Cell Line, Tumor; Endopeptidases; Fibroblasts; Gallium Radioisotopes; Humans; Membrane Proteins; Mice; Pancreatic Neoplasms; Radiopharmaceuticals; Tissue Distribution
PubMed: 34593598
DOI: 10.2967/jnumed.121.262533 -
Antimicrobial Agents and Chemotherapy Jun 2022The objective of this study was to describe the total and unbound population pharmacokinetics of ceftriaxone in critically ill adult patients and to define optimized...
The objective of this study was to describe the total and unbound population pharmacokinetics of ceftriaxone in critically ill adult patients and to define optimized dosing regimens. Total and unbound ceftriaxone concentrations were obtained from two pharmacokinetic studies and from a therapeutic drug monitoring (TDM) program at a tertiary hospital intensive care unit. Population pharmacokinetic analysis and Monte Carlo simulations were used to assess the probability of achieving a free trough concentration/MIC ratio of ≥1 using Pmetrics for R. A total of 474 samples (267 total and 207 unbound) were available from 36 patients. A two-compartment model describing ceftriaxone-albumin binding with both nonrenal and renal elimination incorporating creatinine clearance to explain the between-patient variability best described the data. An albumin concentration of ≤20 g/L decreased the probability of target attainment (PTA) by up to 20% across different dosing regimens and simulated creatinine clearances. A ceftriaxone dose of 1 g twice daily is likely therapeutic in patients with creatinine clearance of <100 mL/min infected with susceptible isolates (PTA, ~90%). Higher doses administered as a continuous infusion (4 g/day) are needed in patients with augmented renal clearance (creatinine clearance, >130 mL/min) who are infected by pathogens with a MIC of ≥0.5 mg/L. The ceftriaxone dose should be based on the patient's renal function and albumin concentration, as well as the isolate MIC. Hypoalbuminemia decreases the PTA in patients receiving intermittent dosing by up to 20%.
Topics: Adult; Albumins; Anti-Bacterial Agents; Ceftriaxone; Creatinine; Critical Illness; Humans; Microbial Sensitivity Tests; Monte Carlo Method
PubMed: 35575578
DOI: 10.1128/aac.02189-21 -
Clinical Pharmacokinetics Jun 2023Daratumumab is a fully human, monoclonal immunoglobulin G1 and a first-in-class CD38-targeting drug approved by the US Food and Drug Administration for the treatment of... (Review)
Review
Daratumumab is a fully human, monoclonal immunoglobulin G1 and a first-in-class CD38-targeting drug approved by the US Food and Drug Administration for the treatment of patients with relapsed/refractory and newly diagnosed multiple myeloma or newly diagnosed light-chain amyloidosis. CD38 is heavily expressed on malignant myeloma cells, and daratumumab exerts anti-myeloma activity via immune-mediated mechanisms, direct induction of apoptosis, and immunomodulation. Daratumumab is used as monotherapy or in combination with standard-of-care myeloma therapies, including proteasome inhibitors, immunomodulatory agents, DNA-alkylating agents, and corticosteroids. Following an intravenous infusion, daratumumab exhibits nonlinear pharmacokinetics (PK), as clearance decreases with higher doses and over time because of target-mediated effects. Dosing schedules vary depending on indications and co-administered drugs, but generally daratumumab is administered weekly for 6-9 weeks followed by a less frequent dosing regimen, once every 2-4 weeks. Daratumumab exposure is strongly correlated with efficacy, and the exposure-efficacy relationship follows a maximal effect model, whereas exposure is not correlated with safety endpoints. The approved dose of 16 mg/kg of daratumumab results in the saturation of 99% of the target at the end of weekly dosing in most patients, and high target saturation is maintained over time during the less frequent dosing schedule. Infusion-related reactions are frequently observed in patients given daratumumab, particularly with the first infusion, thus prompting long durations of infusion (~ 7 h) and splitting of the first dose across 2 days. This led to the development of a subcutaneous delivery formulation for daratumumab (Dara-SC). Dara-SC provides a similar efficacy and safety profile to intravenous daratumumab (Dara-IV) but has a much lower rate of infusion-related reactions and a shorter infusion time. Exposure-response relationships for efficacy and safety endpoints were similar between Dara-SC and Dara-IV, and co-administered drugs with either Dara-IV or Dara-SC do not significantly affect daratumumab PK. Except for baseline myeloma type and albumin level, none of the other investigated disease and patient characteristics (renal/hepatic function, age, sex, race, weight, Eastern Cooperative Oncology Group performance status) was identified to have clinically relevant effects on exposure to daratumumab monotherapy or combination therapy regimens. Dara-IV exposure was significantly lower in patients with immunoglobulin G myeloma compared with patients with non-immunoglobulin G myeloma (p < 0.0001) and in patients with a lower albumin level, whereas the overall response rate was similar regardless of the myeloma type and albumin level. Daratumumab dose adjustment is not currently recommended based on disease and patient characteristics.
Topics: Humans; Antineoplastic Agents; Antibodies, Monoclonal; Multiple Myeloma; Albumins; Antineoplastic Combined Chemotherapy Protocols
PubMed: 37129750
DOI: 10.1007/s40262-023-01240-8 -
Gastroenterology Oct 2023Although transient bacteremia is common during dental and endoscopic procedures, infections developing during sterile diseases like acute pancreatitis (AP) can have...
BACKGROUND & AIMS
Although transient bacteremia is common during dental and endoscopic procedures, infections developing during sterile diseases like acute pancreatitis (AP) can have grave consequences. We examined how impaired bacterial clearance may cause this transition.
METHODS
Blood samples from patients with AP, normal controls, and rodents with pancreatitis or those administered different nonesterified fatty acids (NEFAs) were analyzed for albumin-unbound NEFAs, microbiome, and inflammatory cell injury. Macrophage uptake of unbound NEFAs using a novel coumarin tracer were done and the downstream effects-NEFA-membrane phospholipid (phosphatidylcholine) interactions-were studied on isothermal titration calorimetry.
RESULTS
Patients with infected AP had higher circulating unsaturated NEFAs; unbound NEFAs, including linoleic acid (LA) and oleic acid (OA); higher bacterial 16S DNA; mitochondrial DNA; altered β-diversity; enrichment in Pseudomonadales; and increased annexin V-positive myeloid (CD14) and CD3-positive T cells on admission. These, and increased circulating dead inflammatory cells, were also noted in rodents with unbound, unsaturated NEFAs. Isothermal titration calorimetry showed progressively stronger unbound LA interactions with aqueous media, phosphatidylcholine, cardiolipin, and albumin. Unbound NEFAs were taken into protein-free membranes, cells, and mitochondria, inducing voltage-dependent anion channel oligomerization, reducing ATP, and impairing phagocytosis. These were reversed by albumin. In vivo, unbound LA and OA increased bacterial loads and impaired phagocytosis, causing infection. LA and OA were more potent for these amphipathic interactions than the hydrophobic palmitic acid.
CONCLUSIONS
Release of stored LA and OA can increase their circulating unbound levels and cause amphipathic liponecrosis of immune cells via uptake by membrane phospholipids. This impairs bacterial clearance and causes infection during sterile inflammation.
Topics: Humans; Acute Disease; Pancreatitis; Fatty Acids, Nonesterified; Oleic Acid; Inflammation; Albumins; Phosphatidylcholines
PubMed: 37263302
DOI: 10.1053/j.gastro.2023.05.034 -
American Journal of Kidney Diseases :... May 2022Tubular secretion plays an important role in the efficient elimination of endogenous solutes and medications, and lower secretory clearance is associated with risk of...
RATIONALE & OBJECTIVE
Tubular secretion plays an important role in the efficient elimination of endogenous solutes and medications, and lower secretory clearance is associated with risk of kidney function decline. We evaluated whether histopathologic quantification of interstitial fibrosis and tubular atrophy (IFTA) is associated with lower tubular secretory clearance in persons undergoing kidney biopsy.
STUDY DESIGN
Cross-sectional.
SETTINGS & PARTICIPANTS
The Boston Kidney Biopsy Cohort is a study of persons undergoing native kidney biopsies for clinical indications.
EXPOSURES
Semiquantitative score of IFTA reported by 2 trained pathologists.
OUTCOMES
We measured plasma and urine concentrations of 9 endogenous secretory solutes using a targeted liquid chromatography/mass spectrometry assay. We used linear regression to test associations of urine-to-plasma ratios (UPRs) of these solutes with IFTA score after controlling for estimated glomerular filtration rate (eGFR) and albuminuria.
RESULTS
Among 418 participants, mean age was 53 years, 51% were women, 64% were White, and 18% were Black. Mean eGFR was 50mL/min/1.73m, and median urinary albumin-creatinine ratio was 819mg/g. Compared with individuals with≤25% IFTA, those with>50% IFTA had 12%-37% lower UPRs for all 9 secretory solutes. Adjusting for age, sex, race, eGFR, and urine albumin and creatinine levels attenuated the associations, yet a trend of lower secretion across groups remained statistically significant (P<0.05 for trend) for 7 of 9 solutes. A standardized composite secretory score incorporating UPR for all 9 secretory solutes using the min-max method showed similar results (P<0.05 for trend).
LIMITATIONS
Single time point and spot measures of secretory solutes.
CONCLUSIONS
Greater IFTA severity is associated with lower clearance of endogenous secretory solutes even after adjusting for eGFR and albuminuria.
Topics: Albumins; Albuminuria; Creatinine; Cross-Sectional Studies; Female; Fibrosis; Glomerular Filtration Rate; Humans; Kidney; Kidney Diseases; Kidney Tubules; Male; Middle Aged
PubMed: 34571064
DOI: 10.1053/j.ajkd.2021.08.015 -
Frontiers in Immunology 2023Acute respiratory distress syndrome (ARDS) is a common complication of influenza virus (IV) infection. During ARDS, alveolar protein concentrations often reach 40-90% of...
INTRODUCTION
Acute respiratory distress syndrome (ARDS) is a common complication of influenza virus (IV) infection. During ARDS, alveolar protein concentrations often reach 40-90% of plasma levels, causing severe impairment of gas exchange and promoting deleterious alveolar remodeling. Protein clearance from the alveolar space is at least in part facilitated by the multi-ligand receptor megalin through clathrin-mediated endocytosis.
METHODS
To investigate whether IV infection impairs alveolar protein clearance, we examined albumin uptake and megalin expression in MLE-12 cells and alveolar epithelial cells (AEC) from murine precision-cut lung slices (PCLS) and in vivo, under IV infection conditions by flow cytometry and western blot. Transcriptional levels from AEC and broncho-alveolar lavage (BAL) cells were analyzed in an in-vivo mouse model by RNAseq.
RESULTS
IV significantly downregulated albumin uptake, independently of activation of the TGF-β1/GSK3β axis that has been previously implicated in the regulation of megalin function. Decreased plasma membrane abundance, total protein levels, and mRNA expression of megalin were associated with this phenotype. In IV-infected mice, we identified a significant upregulation of matrix metalloproteinase (MMP)-14 in BAL fluid cells. Furthermore, the inhibition of this protease partially recovered total megalin levels and albumin uptake.
DISCUSSION
Our results suggest that the previously described MMP-driven shedding mechanisms are potentially involved in downregulation of megalin cell surface abundance and clearance of excess alveolar protein. As lower alveolar edema protein concentrations are associated with better outcomes in respiratory failure, our findings highlight the therapeutic potential of a timely MMP inhibition in the treatment of IV-induced ARDS.
Topics: Animals; Mice; Alveolar Epithelial Cells; Low Density Lipoprotein Receptor-Related Protein-2; Biological Transport; Albumins; Orthomyxoviridae Infections; Orthomyxoviridae
PubMed: 37727782
DOI: 10.3389/fimmu.2023.1260973 -
Scientific Reports Jul 2022The aim of this study was to evaluate the prognostic value of the Lactate to Albumin (L/A) ratio compared to that of lactate and lactate clearance in predicting outcomes... (Comparative Study)
Comparative Study Observational Study
Comparison of lactate/albumin ratio to lactate and lactate clearance for predicting outcomes in patients with septic shock admitted to intensive care unit: an observational study.
The aim of this study was to evaluate the prognostic value of the Lactate to Albumin (L/A) ratio compared to that of lactate and lactate clearance in predicting outcomes in patients with septic shock. This was a multi-center observational study of adult patients with septic shock, who admitted to intensive care units (ICUs) at Shohada and Imam Reza Hospitals, Tabriz, Iran, between Sept 2018 and Jan 2021. The area under the curve (AUC) of receiver operating characteristic (ROC) curve and multivariate logistic regression analyses were used to explore associations of the L/A ratio, lactate and lactate clearance on the primary (mortality) and secondary outcomes [ICU length of stay (LOS), duration of mechanical ventilation (MV), need of renal replacement therapy (RRT) and duration of using vasopressors] at baseline, 6 h and 24 h of septic shock recognition. Best performing predictive value for mortality were related to lactate clearance at 24 h, L/A ratio at 6 h and lactate levels at 24 h with (AUC 0.963, 95% CI 0.918-0.987, P < 0.001), (AUC 0.917, 95% CI 0.861-0.956, P < 0.001), and (AUC 0.904, 95% CI 0.845-0.946, P < 0.001), respectively. Generally, the lactate clearance at 24 h had better prognostic performance for mortality and duration of using vasopressor. However, the L/A ratio had better prognostic performance than serum lactate and lactate clearance for RRT, ICU LOS and MV duration.
Topics: Adult; Albumins; Humans; Intensive Care Units; Lactic Acid; Prognosis; ROC Curve; Retrospective Studies; Shock, Septic
PubMed: 35906231
DOI: 10.1038/s41598-022-14764-z -
Journal of Nuclear Medicine : Official... May 2023Fibroblast activation protein (FAP) has received increasing attention as an oncologic target because of its prominent expression in solid tumors but virtual absence from...
Fibroblast activation protein (FAP) has received increasing attention as an oncologic target because of its prominent expression in solid tumors but virtual absence from healthy tissues. Most radioligand therapies (RLTs) targeting FAP, however, suffer from inadequate tumor retention or clearance from healthy tissues. Herein we report a FAP-targeted RLT comprising an FAP6 ligand conjugated to DOTA and an albumin binder (4--iodophenylbutyric acid, or IP) for enhanced pharmacokinetics. We evaluated the performance of the resulting FAP6-IP-DOTA conjugate in 4 tumor models, 3 of which express FAP only on cancer-associated fibroblasts, that is, analogously to human tumors. Single-cell RNA-sequencing data were analyzed from 34 human breast, ovarian, colorectal, and lung cancers to quantify FAP-overexpressing cells. FAP6-DOTA conjugates were synthesized with or without an albumin binder (IP) and investigated for binding to human FAP-expressing cells. Accumulation of In- or Lu-labeled conjugates in KB, HT29, U87MG, and 4T1 murine tumors was also assessed by radioimaging or biodistribution analyses. Radiotherapeutic potency was quantitated by measuring tumor volumes versus time. Approximately 5% of all cells in human tumors overexpressed FAP (cancer-associated fibroblasts comprised ∼77% of this FAP-positive subpopulation, whereas ∼2% were cancer cells). FAP6 conjugates bound to FAP-expressing cells with high affinity (dissociation constant, ∼1 nM). Lu-FAP6-IP-DOTA achieved an 88-fold higher tumor dose than Lu-FAP6-DOTA and improved all tumor-to-healthy-organ ratios. Single doses of Lu-FAP6-IP-DOTA suppressed tumor growth by about 45% in all tested tumor models without causing reproducible toxicities. We conclude that Lu-FAP6-IP-DOTA constitutes a promising candidate for FAP-targeted RLT of solid tumors.
Topics: Humans; Animals; Mice; Tissue Distribution; Cell Line, Tumor; Albumins; Fibroblasts
PubMed: 37116911
DOI: 10.2967/jnumed.122.264494