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A major cause of osteoporosis is impaired coupled bone formation. Mechanistically, both osteoclast-derived and bone-derived growth factors have been previously implicated. Here, we hypothesize that the release of bone calcium during osteoclastic bone resorption is essential for coupled bone formation. Osteoclastic resorption increases interstitial fluid calcium locally from the normal 1.8 mM up to 5 mM. MC3T3-E1 osteoprogenitor cells, cultured in a 3.6 mM calcium medium, demonstrated that calcium signaling stimulated osteogenic cell proliferation, differentiation, and migration. Calcium channel knockdown studies implicated calcium channels, Cav1.2, store-operated calcium entry (SOCE), and calcium-sensing receptor (CaSR) in regulating bone cell anabolic activities. MC3T3–E1 cells cultured in a 3.6 mM calcium medium expressed increased gene expression of Wnt signaling and growth factors platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and bone morphogenic protein-2 (BMP 2). Our coupling model of bone formation, the receptor activator of nuclear factor-κΒ ligand (RANKL)-treated mouse calvaria, confirmed the role of calcium signaling in coupled bone formation by exhibiting increased gene expression for osterix and osteocalcin. Critically, dual immunocytochemistry showed that RANKL treatment increased osterix-positive cells and increased fluorescence intensity of Cav1.2 and CaSR protein expression per osterix-positive cell. The above data established that calcium released by osteoclasts contributed to the regulation of coupled bone formation. CRISPR/Cas-9 knockout of Cav1.2 in osteoprogenitor cells cultured in basal calcium medium caused a >80% decrease in the expression of downstream osteogenic genes, emphasizing the large magnitude of the effect of calcium signaling. Thus, calcium signaling is a major regulator of coupled bone formation.

Background: Fluid therapy plays a major role in the management of critically ill patients. Yet assessment of intravascular volume in these patients is challenging. Different invasive and non-invasive methods have been used with variable results. The passive leg raise (PLR) maneuver has been recommended by international guidelines as a means to determine appropriate fluid resuscitation. We performed this systematic review and meta-analysis to determine if using this method of volume assessment has an impact on mortality outcome in patients with septic shock. Methods: This study is a systematic review and meta-analysis. We searched available data in the MEDLINE, CINAHL, EMBASE, and CENTRAL databases from inception until October 2020 for prospective, randomized, controlled trials that compared PLR-guided fluid resuscitation to standard care in adult patients with septic shock. Our primary outcome was mortality at the longest duration of follow-up. Results: We screened 1,425 article titles and abstracts. Of the 23 full-text articles reviewed, 5 studies with 462 patients met our eligibility criteria. Odds ratios (ORs) and associated 95% confidence intervals (CIs) for mortality at the longest reported time interval were calculated for each study. Using random effects modeling, the pooled OR (95% CI) for mortality with a PLR-guided resuscitation strategy was 0.82 (0.52 -1.30). The included studies were not blinded and they ranged from having low to high risk of bias using the Cochrane Risk of Bias Tool. Conclusion: Our analysis showed there was no statistically significant difference in mortality among septic shock patients treated with PLR-guided resuscitation vs. those with standard care.

Acute liver injury is a common disease without effective therapy in humans. We sought to evaluate a combination therapy of insulin-like growth factor 1 (IGF-I) and BTP-2 in a mouse liver injury model induced by lipopolysaccharide (LPS). We chose this model because LPS is known to increase the expression of the transcription factors related to systemic inflammation (i.e., NFκB, CREB, AP1, IRF 3, and NFAT), which depends on calcium signaling. Notably, these transcription factors all have pleiotropic effects and account for the other observed changes in tissue damage parameters. Additionally, LPS is also known to increase the genes associated with a tissue injury (e.g., NGAL, SOD, caspase 3, and type 1 collagen) and systemic expression of pro-inflammatory cytokines. Finally, LPS compromises vascular integrity. Accordingly, IGF-I was selected because its serum levels were shown to decrease during systemic inflammation. BTP-2 was chosen because it was known to decrease cytosolic calcium, which is increased by LPS. This current study showed that IGF-I, BTP-2, or a combination therapy significantly altered and normalized all of the aforementioned LPS-induced gene changes. Additionally, our therapies reduced the vascular leakage caused by LPS, as evidenced by the Evans blue dye technique. Furthermore, histopathologic studies showed that IGF-I decreased the proportion of hepatocytes with ballooning degeneration. Finally, IGF-I also increased the expression of the hepatic growth factor (HGF) and the receptor for the epidermal growth factor (EGFR), markers of liver regeneration. Collectively, our data suggest that a combination of IGF-I and BTP-2 is a promising therapy for acute liver injury.

Therapeutic apheresis has been used in treating hematological and non-hematological diseases. For a successful procedure, efficient vascular access is required. Presently, peripheral venous access (PVA), central venous catheterization (CVC), implantable ports, and arteriovenous fistulas (AVFs) are used. This review aims to evaluate different type of access and their pros and cons to help physicians determine the best venous access.The electronic search included PubMed and Google Scholar up to November 2020. The Mesh terms were apheresis, peripheral catheterization, central catheterization, and arteriovenous fistula.A total of 228 studies were found through database searching. Two independent authors reviewed the articles using their titles and abstracts; 88 articles were selected and the full text was reviewed. Finally, 26 were included. The inclusion criteria were studies incorporating patients with any indication for apheresis.PVA has been promoted in recent years in many centers across the United States to lower the rate of complications associated with vascular access and to make this procedure more accessible. Several factors are involved in selecting appropriate venous access, such as the procedure's duration and frequency, patient's vascular anatomy, and staff's experience. In short-term procedures, temporary vascular access like PVA or CVC is preferred. Permanent vascular access such as AVF, tunneled cuffed central lines, and implantable ports are more beneficial in prolonged treatment period but each patient has to be evaluated individually by apheresis team for the most appropriate method.

Acute lung injury (ALI) afflicts approximately 200,000 patients annually and has a 40% mortality rate. The COVID-19 pandemic has massively increased the rate of ALI incidence. The pathogenesis of ALI involves tissue damage from invading microbes and, in severe cases, the overexpression of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). This study aimed to develop a therapy to normalize the excess production of inflammatory cytokines and promote tissue repair in the lipopolysaccharide (LPS)-induced ALI. Based on our previous studies, we tested the insulin-like growth factor I (IGF-I) and BTP-2 therapies. IGF-I was selected, because we and others have shown that elevated inflammatory cytokines suppress the expression of growth hormone receptors in the liver, leading to a decrease in the circulating IGF-I. IGF-I is a growth factor that increases vascular protection, enhances tissue repair, and decreases pro-inflammatory cytokines. It is also required to produce anti-inflammatory 1,25-dihydroxyvitamin D. BTP-2, an inhibitor of cytosolic calcium, was used to suppress the LPS-induced increase in cytosolic calcium, which otherwise leads to an increase in proinflammatory cytokines. We showed that LPS increased the expression of the primary inflammatory mediators such as toll like receptor-4 (TLR-4), IL-1β, interleukin-17 (IL-17), TNF-α, and interferon-γ (IFN-γ), which were normalized by the IGF-I + BTP-2 dual therapy in the lungs, along with improved vascular gene expression markers. The histologic lung injury score was markedly elevated by LPS and reduced to normal by the combination therapy. In conclusion, the LPS-induced increases in inflammatory cytokines, vascular injuries, and lung injuries were all improved by IGF-I + BTP-2 combination therapy.

Angiotensin-converting enzyme inhibitors (ACEi) are frequently used antihypertensive medications with additional advantages such as reducing proteinuria and cardiovascular events. ACEi are commonly held at least 24 hours before a therapeutic plasma exchange (TPE) to reduce possibility of adverse events (AEs) including adverse drug reactions (ADR). The objective of this study was to determine if ACEi use increases the risk of ADR in patients receiving TPE with a conventional centrifuge-based apheresis system. This is a retrospective chart review study (n = 252; 52% male). Binary logistic regression was used to analyze the association of ACEi use and AEs. Of 171 patients who had AE during TPE, only 38 patients were taking ACEi. There was no significant association between ACEi use and AEs after adjustments (odds ratio = 0.885, 95% confidence interval: 0.468, 1.674). Our results suggest that risk of AEs is not higher in patients taking ACEi receiving TPE using a centrifuge-based machine. Randomized controlled prospective trials may be needed to further investigate this matter.

This study was undertaken to test two therapies for acute kidney injury (AKI) prevention, IGF-1, which is renal protective, and BTP-2, which is a calcium entry (SOCE) inhibitor. We utilized lipopolysaccharide (LPS) IP, as a systemic model of AKI and studied in five groups of animals. Three experiments showed that at 7 days: (1) LPS significantly reduced serum IGF-1 and intramuscular IGF-I in vivo gene therapy rescued this deficiency. (2) Next, at the 7-day time point, our combination therapy, compared to the untreated group, caused a significant increase in survival, which was noteworthy because all of the untreated animals died in 72 h. (3) The four pathways associated with inflammation, including (A) increase in cytosolic calcium, (B) elaboration of proinflammatory cytokines, (C) impairment of vascular integrity, and (D) cell injury, were adversely affected in renal tissue by LPS, using a sublethal dose of LPS. The expression of several genes was measured in each of the above pathways. The combined therapy of IGF-1 and BTP-2 caused a favorable gene expression response in all four pathways. Our current study was an AKI study, but these pathways are also involved in other types of severe inflammation, including sepsis, acute respiratory distress syndrome, and probably severe coronavirus infection.

INTRODUCTION Red blood cells exchange transfusion has been demonstrated to be helpful in treatment of sever P. falciparum malaria. However, no large scale randomized controlled trials have been completed to date and the CDC does not recommend RBC exchange transfusions as standard of care. We present a case of severe cerebral malaria in a patient with extremely high parasitemia and severe altered mental status who improved rapidly with automated RBC exchange. REPORT Seventy-two year old female presented with 1 day history of weakness, altered mental status, malaise, and cyclic sweats after returning from a trip to Sierra Leone. Thick and Thin Smears demonstrated P. falciparum rings present and Quantitative malaria screen demonstrated 53.33% parasitemia. Patient was started on quinidine and doxycycline but continued to deteriorate. Automated RBC exchange transfusion was performed within 24 hours of admission and resulted in rapid improvement in symptomology. Repeat thick and thin smears revealed undetectable parasite load. CONCLUSION Automated RBC exchange may improve outcomes in severe P. falciparum malaria when presenting parasite loads are very high.