Definitions of massive transfusion in adults with critical bleeding: a systematic review.

BACKGROUND: Definitions for massive transfusion (MT) vary widely between studies, contributing to challenges in interpretation of research findings and practice evaluation. In this first systematic review, we aimed to identify all MT definitions used in randomised controlled trials (RCTs) to date to inform the development of consensus definitions for MT. METHODS: We systematically searched the following databases for RCTs from inception until 11 August 2022: MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Cumulative Index to Nursing and Allied Health Literature, and Transfusion Evidence Library. Ongoing trials were sought from CENTRAL, ClinicalTrials.gov, and World Health Organisation International Clinical Trials Registry Platform. To be eligible for inclusion, studies had to fulfil all the following three criteria: (1) be an RCT; (2) include an adult patient population with major bleeding who had received, or were anticipated to receive, an MT in any clinical setting; and (3) specify a definition for MT as an inclusion criterion or outcome measure. RESULTS: Of the 8,458 distinct references identified, 30 trials were included for analysis (19 published, 11 ongoing). Trauma was the most common clinical setting in published trials, while for ongoing trials, it was obstetrics. A total of 15 different definitions of MT were identified across published and ongoing trials, varying greatly in cut-offs for volume transfused and time period. Almost all definitions specified the number of red blood cells (RBCs) within a set time period, with none including plasma, platelets or other haemostatic agents that are part of contemporary transfusion resuscitation. For completed trials, the most commonly used definition was transfusion of ≥ 10 RBC units in 24 h (9/19, all in trauma), while for ongoing trials it was 3-5 RBC units (n = 7), with the timing for transfusion being poorly defined, or in some trials not provided at all (n = 5). CONCLUSIONS: Transfusion of ≥ 10 RBC units within 24 h was the most commonly used definition in published RCTs, while lower RBC volumes are being used in ongoing RCTs. Any consensus definitions should reflect the need to incorporate different blood components/products for MT and agree on whether a 'one-size-fits-all' approach should be used across different clinical settings.

Clonal hematopoiesis, myeloid disorders and BAX-mutated myelopoiesis in patients receiving venetoclax for CLL.

The BCL2 inhibitor venetoclax has established therapeutic roles in chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML). As BCL2 is an important determinant of survival of both myeloid progenitor and B cells, we investigated whether clinical and molecular abnormalities arise in the myeloid compartment during long-term continuous venetoclax treatment of CLL in 89 patients (87 with relapsed/refractory CLL). Over a median follow-up of 75 (range 21-98) months, persistent cytopenias (≥1 of neutropenia, thrombocytopenia, anemia) lasting ≥4 months and unrelated to CLL occurred in 25 patients (28%). Of these patients, 20 (80%) displayed clonal hematopoiesis, including 10 with therapy-related myeloid neoplasms (t-MNs). t-MNs occurred exclusively in patients previously exposed to fludarabine-alkylator combination therapy with a cumulative 5-year incidence of 10.4% after venetoclax initiation, consistent with rates reported for patients exposed to fludarabine-alkylator combination therapy without venetoclax. To determine whether the altered myelopoiesis reflected the acquisition of mutations, we analyzed samples from patients with no or minimal bone marrow CLL burden (n = 41). Mutations in the apoptosis effector BAX were identified in 32% (13/41). In cellular assays, C-terminal BAX mutants abrogated outer mitochondrial membrane localization of BAX and engendered resistance to venetoclax killing. BAX-mutated clonal hematopoiesis occurred independently of prior fludarabine-alkylator combination therapy exposure and was not associated with t-MNs. Single-cell sequencing revealed clonal co-occurrence of mutations in BAX with DNMT3A or ASXL1. We also observed simultaneous BCL2 mutations within CLL cells and BAX mutations in the myeloid compartment of the same patients, indicating lineage-specific adaptation to venetoclax therapy.

Outcomes of patients with CLL sequentially resistant to both BCL2 and BTK inhibition.

Covalent Bruton tyrosine kinase inhibitors (BTKi's) and the B-cell lymphoma 2 (BCL2) inhibitor venetoclax have significantly improved outcomes for patients with chronic lymphocytic leukemia (CLL), especially those with biologically adverse disease. Patients with CLL resistant to their first targeted agent (TA) can be effectively treated with the alternative class. However, relapses are expected with second-line TA therapy, and the clinical challenge of double class-resistant disease is now emerging with increasing frequency. To define the characteristics and outcomes of patients with double class-resistant disease, we retrospectively analyzed 17 patients who developed progressive disease (PD) on both TA classes for CLL (venetoclax, then BTKi, n=12; BTKi, then venetoclax, n = 5). The cohort was heavily pretreated (median lines of prior therapy, 4) and enriched for adverse disease genetics (complex karyotype, 12 of 12 tested [100%]; del(17p)/TP53 mutations, 15 of 17 [88%]). The median time to progression on prior venetoclax was 24 months (range, 6-94 months) and was 25 months (range, 1-55 months) on prior BTKi. Progression on second-line TA was manifest as progressive CLL in 11 patients and as Richter transformation in 6. The median overall survival after progression on second-line TA was 3.6 months (95% confidence interval, 2-11 months). Patients with double class-resistant CLL have a dismal prognosis, representing a group of high unmet need.

BH3 Mimetics for the Treatment of B-Cell Malignancies-Insights and Lessons from the Clinic.

The discovery of the link between defective apoptotic regulation and cancer cell survival engendered the idea of targeting aberrant components of the apoptotic machinery for cancer therapy. The intrinsic pathway of apoptosis is tightly controlled by interactions amongst members of three distinct subgroups of the B-cell lymphoma 2 (BCL2) family of proteins. The pro-survival BCL2 proteins prevent apoptosis by keeping the pro-apoptotic effector proteins BCL2-associated X protein (BAX) and BCL2 homologous antagonist/killer (BAK) in check, while the BH3-only proteins initiate apoptosis by either neutralizing the pro-survival BCL2 proteins or directly activating the pro-apoptotic effector proteins. This tripartite regulatory mechanism is commonly perturbed in B-cell malignancies facilitating cell death evasion. Over the past two decades, structure-based drug discovery has resulted in the development of a series of small molecules that mimic the function of BH3-only proteins called the BH3 mimetics. The most clinically advanced of these is venetoclax, which is a highly selective inhibitor of BCL2 that has transformed the treatment landscape for chronic lymphocytic leukemia (CLL). Other BH3 mimetics, which selectively target myeloid cell leukemia 1 (MCL1) and B-cell lymphoma extra large (BCLxL), are currently under investigation for use in diverse malignancies. Here, we review the current role of BH3 mimetics in the treatment of CLL and other B-cell malignancies and address open questions in this rapidly evolving field.

BTK inhibitor therapy is effective in patients with CLL resistant to venetoclax.

Highly active BTK inhibitors (BTKis) and the BCL2 inhibitor venetoclax have transformed the therapeutic landscape for chronic lymphocytic leukemia (CLL). Results of prospective clinical trials demonstrate the efficacy of venetoclax to salvage patients with disease progression on BTKis, but data on BTKi therapy after disease progression on venetoclax are limited, especially regarding durability of benefit. We retrospectively evaluated the records of 23 consecutive patients with relapsed/refractory CLL who received a BTKi (ibrutinib, n = 21; zanubrutinib, n = 2) after stopping venetoclax because of progressive disease. Median progression-free survival (PFS) and median overall survival after BTKi initiation were 34 months (range, <1 to 49) and 42 months (range, 2-49), respectively. Prior remission duration ≥24 months and attainment of complete remission or undetectable measurable residual disease on venetoclax were associated with longer PFS after BTKi salvage (P = .044 and P = .029, respectively). BTKi therapy achieved durable benefit for patients with the BCL2 Gly101Val venetoclax resistance mutation (estimated 24-month PFS, 69%). At a median survivor follow-up of 33 months (range, 2-53), 11 patients remained on BTKi and 12 had stopped therapy because of disease progression (n = 8) or toxicity (n = 4). Our findings indicate that BTKi therapy can provide durable CLL control after disease progression on venetoclax.

Undetectable peripheral blood MRD should be the goal of venetoclax in CLL, but attainment plateaus after 24 months.

The highly selective BCL2 inhibitor venetoclax achieves deep responses in patients with relapsed or refractory (R/R) chronic lymphocytic leukemia (CLL), including undetectable minimal residual disease (uMRD). We retrospectively reviewed 62 patients with CLL treated with venetoclax to investigate the performance of peripheral blood (PB) compared with bone marrow (BM) assessment of MRD; the kinetics, clinicopathological associations, and longer-term outcomes of uMRD attainment and recrudescence; and the ability of venetoclax dose escalation to deepen responses. Among 16 patients who achieved PB uMRD and had contemporaneous BM assessments, 13 (81%) had confirmed BM uMRD, and patients with PB uMRD had outcomes at least as favorable as those with BM uMRD for time to progression, overall survival, and MRD recrudescence. Excluding 2 patients lacking earlier assessment, the median time to PB uMRD was 18 (range, 5-26) months, with 90% of instances achieved by 24 months. There was no new PB uMRD attainment after 24 months without treatment intensification. The dominant association with earlier attainment of uMRD was concurrent rituximab (P = .012). Complex karyotype was associated with inferior uMRD attainment after 12 months of therapy (P = .015), and patients attaining uMRD whose disease harbored TP53 abnormalities demonstrated a trend toward earlier recrudescence (P = .089). Of patients who received venetoclax dose escalations, 4 (27%) of 15 achieved improvements in response. For patients with R/R CLL receiving venetoclax, PB uMRD commonly correlates with BM uMRD and is associated with a comparable longer-term prognosis. Concurrent rituximab augments uMRD attainment, but dose escalation and further treatment beyond 24 months infrequently deepen responses.

Mesoporous silica nanoparticle-mediated intracellular cre protein delivery for maize genome editing via loxP site excision.

The delivery of proteins instead of DNA into plant cells allows for a transient presence of the protein or enzyme that can be useful for biochemical analysis or genome modifications. This may be of particular interest for genome editing, because it can avoid DNA (transgene) integration into the genome and generate precisely modified "nontransgenic" plants. In this work, we explore direct protein delivery to plant cells using mesoporous silica nanoparticles (MSNs) as carriers to deliver Cre recombinase protein into maize (Zea mays) cells. Cre protein was loaded inside the pores of gold-plated MSNs, and these particles were delivered by the biolistic method to plant cells harboring loxP sites flanking a selection gene and a reporter gene. Cre protein was released inside the cell, leading to recombination of the loxP sites and elimination of both genes. Visual selection was used to select recombination events from which fertile plants were regenerated. Up to 20% of bombarded embryos produced calli with the recombined loxP sites under our experimental conditions. This direct and reproducible technology offers an alternative for DNA-free genome-editing technologies in which MSNs can be tailored to accommodate the desired enzyme and to reach the desired tissue through the biolistic method.

Controlling reactivity of nanoporous catalyst materials by tuning reaction product-pore interior interactions: statistical mechanical modeling.

Statistical mechanical modeling is performed of a catalytic conversion reaction within a functionalized nanoporous material to assess the effect of varying the reaction product-pore interior interaction from attractive to repulsive. A strong enhancement in reactivity is observed not just due to the shift in reaction equilibrium towards completion but also due to enhanced transport within the pore resulting from reduced loading. The latter effect is strongest for highly restricted transport (single-file diffusion), and applies even for irreversible reactions. The analysis is performed utilizing a generalized hydrodynamic formulation of the reaction-diffusion equations which can reliably capture the complex interplay between reaction and restricted transport.

A magnetic mesoporous silica nanoparticle-based drug delivery system for photosensitive cooperative treatment of cancer with a mesopore-capping agent and mesopore-loaded drug.

Lately, there has been a growing interest in anticancer therapy with a combination of different drugs that work by different mechanisms of action, which decreases the possibility that resistant cancer cells will develop. Herein we report on the development of a drug delivery system for photosensitive delivery of a known anticancer drug camptothecin along with cytotoxic cadmium sulfide nanoparticles from a magnetic drug nanocarrier. Core-shell nanoparticles consisting of magnetic iron-oxide-cores and mesoporous silica shells are synthesized with a high surface area (859 m(2) g(-1)) and hexagonal packing of mesopores, which are 2.6 nm in diameter. The mesopores are loaded with anticancer drug camptothecin while entrances of the mesopores are blocked with 2-nitro-5-mercaptobenzyl alcohol functionalized CdS nanoparticles through a photocleavable carbamate linkage. Camptothecin release from this magnetic drug delivery system is successfully triggered upon irradiation with UV light, as measured by fluorescence spectroscopy. Photosensitive anticancer activity of the drug delivery system is monitored by viability studies on Chinese hamster ovarian cells. The treatment of cancer cells with drug loaded magnetic material leads to a decrease in viability of the cells due to the activity of capping CdS nanoparticles. Upon exposure to low power UV light (365 nm) the loaded camptothecin is released which induces additional decrease in viability of CHO cells. Hence, the capping CdS nanoparticles and loaded camptothecin exert a cooperative anticancer activity. Responsiveness to light irradiation and magnetic activity of the nanocarrier enable its potential application for selective targeted treatment of cancer.

Older adult consumers' attitudes and preferences on electronic patient-physician messaging.

OBJECTIVE: To evaluate and compare the attitudes and preferences of younger and older adults regarding health information exchange with providers, and identify barriers and limitations to meaningful use. STUDY DESIGN: Cross-sectional study. METHODS: Qualitative and quantitative data gathered from online surveys of younger and older adult patients enrolled in a freestanding, Internetbased patient-physician messaging system that requires an individual account. This messaging system is only a secure messaging center, and does not allow for direct access to personal medical records. RESULTS: Data were collected from 324 patients (or proxy users) who reported their age, with 55.2% of respondents under the age of 65 years (mean age 48.2 years) and 44.8% of respondents 65 years or older (mean age 74.9 years). Family and non-family caregivers (proxy users) (mean age 59.2 years) comprised 21.0% of respondents. Overall, 83.9% of all respondents preferred to communicate with the provider via e-mail, and 84.5% of users found the messaging system easy to use, with a majority utilizing the messaging system to communicate about health questions and/or medication requests. Finally, 83% of user respondents were satisfied with the messaging system. Results highlight several areas where improvement is needed to increase patient use and satisfaction including adequate patient education, user-friendly interface, and provider engagement. No significant differences between the younger and older adult populations were found. CONCLUSION: Although a majority of enrolled older adult patients have positive attitudes about health information exchange, electronic communication platforms must address key issues in consumer education, physician commitment, and adoption of an accessible interface to ensure productive older adult consumer participation.

Chemically reducible lipid bilayer coated mesoporous silica nanoparticles demonstrating controlled release and HeLa and normal mouse liver cell biocompatibility and cellular internalization.

A controlled release system composed of mesoporous silica nanoparticles with covalently bound dipalmitoyl moieties supporting phosphorylated lipids has been successfully synthesized and characterized. This MSN system demonstrates controlled release of fluorescein molecules under disulfide reducing conditions. Flow cytometry analyses confirm increased biocompatibility of the resulting lipid bilayer MSNs (LB-MSNs) from nonfunctional MSNs. Fluorescently labeled LB-MSNs are examined via confocal fluorescent microscopy ex vivo and were found to enter both normal and cancer cell lines. The LB-MSNs presented here have potential to be used as rapid and diverse functionalized, stable liposome analogues for drug delivery.

Ligand conformation dictates membrane and endosomal trafficking of arginine-glycine-aspartate (RGD)-functionalized mesoporous silica nanoparticles.

Recent breakthrough research on mesoporous silica nanoparticle (MSN) materials has illustrated their significant potential in biological applications due to their excellent drug delivery and endocytotic behavior. We set out to determine if MSN, covalently functionalized with conformation specific bioactive molecules (either linear or cyclic RGD ligands), behave towards mammalian cells in a similar manner as the free ligands. We discovered that RGD immobilized on the MSN surface did not influence the integrity of the porous matrix and improved the endocytosis efficiency of the MSN materials. Through competition experiments with free RGD ligands, we also discovered a conformation specific receptor-integrin association. The interaction between RGD immobilized on the MSN surface and integrins plays an important role in endosome trafficking, specifically dictating the kinetics of endosomal escape. Thus, covalent functionalization of biomolecules on MSN assists in the design of a system for controlling the interface with cancer cells.

Functional mesoporous silica nanoparticles for the selective sequestration of free fatty acids from microalgal oil.

A series of 2d-hexagonally packed mesoporous silica nanoparticle material with 10 nm pore diameter (MSN-10) covalently functionalized with organic surface modifiers have been synthesized via a post-synthesis grafting method. The material structure has been characterized by powder X-ray diffraction, electron microscopy, and nitrogen sorption analyses, and the free fatty acid (FFA) sequestration capacity and selectivity was investigated and quantified by thermogravimetric and GC/MS analysis. We discovered that aminopropyl functionalized 10 nm pore mesoporous silica nanoparticle material (AP-MSN-10) sequestered all available FFAs and left nearly all other molecules in solution from a simulated microalgal extract containing FFAs, sterols, terpenes, and triacylglycerides. We also demonstrated selective FFA sequestration from commercially available microalgal oil.

Parameters affecting the efficient delivery of mesoporous silica nanoparticle materials and gold nanorods into plant tissues by the biolistic method.

Applying nanotechnology to plant science requires efficient systems for the delivery of nanoparticles (NPs) to plant cells and tissues. The presence of a cell wall in plant cells makes it challenging to extend the NP delivery methods available for animal research. In this work, research is presented which establishes an efficient NP delivery system for plant tissues using the biolistic method. It is shown that the biolistic delivery of mesoporous silica nanoparticle (MSN) materials can be improved by increasing the density of MSNs through gold plating. Additionally, a DNA-coating protocol is used based on calcium chloride and spermidine for MSN and gold nanorods to enhance the NP-mediated DNA delivery. Furthermore, the drastic improvement of NP delivery is demonstrated when the particles are combined with 0.6 µm gold particles during bombardment. The methodology described provides a system for the efficient delivery of NPs into plant cells using the biolistic method.

Luciferase and luciferin co-immobilized mesoporous silica nanoparticle materials for intracellular biocatalysis.

We report a gold nanoparticle (AuNP)-capped mesoporous silica nanoparticle (Au-MSN) platform for intracellular codelivery of an enzyme and a substrate with retention of bioactivity. As a proof-of-concept demonstration, Au-MSNs are shown to release luciferin from the interior pores of MSN upon AuNP uncapping in response to disulfide-reducing antioxidants and codeliver bioactive luciferase from the PEGylated exterior surface of Au-MSN to Hela cells. The effectiveness of luciferase-catalyzed luciferin oxidation and luminescence emission in the presence of intracellular ATP was measured by a luminometer. Overall, the chemical tailorability of the Au-MSN platform to retain enzyme bioactivity, the ability to codeliver enzyme and substrate, and the potential for imaging tumor growth and metastasis afforded by intracellular ATP- and glutathione-dependent bioluminescence make this platform appealing for intracellular controlled catalysis and tumor imaging.

Surfactant-assisted controlled release of hydrophobic drugs using anionic surfactant templated mesoporous silica nanoparticles.

A series of mesoporous silica nanoparticles (MSNs) were synthesized using the co-structure directing method. A non-cytotoxic anionic surfactant, undec-1-en-11-yltetra(ethylene glycol) phosphate monoester surfactant (PMES), was used as a structure directing agent (SDA) together with aminopropyltrimethoxysilane that functioned as a co-structure directing agent (CSDA). The morphology and mesoporous structure of these materials were tuned by changing the molar ratio of CSDA and SDA. These mesoporous nanomaterials containing PMES inside the pores showed excellent biocompatibility in vitro. The cellular internalization and endosome escape of PMES-MSNs in cervical cancer cells (HeLa) was demonstrated by flow cytometry and confocal microscopy, respectively. The PMES-MSNs were used as drug delivery carriers for resveratrol, a low water solubility drug, by taking advantage of the hydrophobic environment created by the PMES micelle inside the pores. This surfactant-assisted delivery strategy was tested under physiological conditions showing an increase of the drug loading compared to the material without surfactant and steady release of resveratrol. Finally, the therapeutic properties of resveratrol-loaded PMES-MSNs were evaluated in vitro using HeLa and Chinese hamster ovarian cells. We envision that this surfactant-assisted drug delivery method using MSNs as nanovehicles would lead to a new generation of carrier materials for intracellular delivery of a variety of hydrophobic therapeutic agents.

Poly(lactic acid)-coated mesoporous silica nanosphere for controlled release of venlafaxine.

Two types of mesoporous silica nanospheres (MSNs) were synthesized for use as controlled-release agents. One was prepared by grafting with 5,6-dihydroxyhexylsilane (DH-MSN) and the other one by further coating with cholic acid-crosslinked poly(lactic acid) (CA-PLA-MSN). We studied the release of the antidepressant venlafaxine from each of the materials in simulated gastric fluid (SGF), in simulated gastric acid solution (SGA), and in simulated intestinal fluid without pancreatin (SIF). The CA-PLA-MSN material was able to significantly delay the release of the drug in intestinal condition compared with gastric acid surrounding due to the fast decomposition rate of PLA in gastric acid. Moreover, it successfully avoided the initial burst to a certain extent in SGF. The enzyme pepsin played a favorable obstruct role in both DH-MSN and CA-PLA-MSN systems to reduce release rate. A model based on Weibull model was built to fit the release results, and based on it, the mechanisms about release processes were brought out tentatively.

Molecular ordering of mixed surfactants in mesoporous silicas: a solid-state NMR study.

The use of mixed surfactants in the synthesis of mesoporous silica nanoparticles (MSNs) is of importance in the context of adjusting pore structures, sizes and morphologies. In the present study, the arrangement of molecules in micelles produced from a mixture of two surfactants, cetyltrimethylammonium bromide (CTAB) and cetylpyridinium bromide (CPB) was detailed by solid-state NMR spectroscopy. Proximities of methyl protons in the trimethylammonium headgroup of CTAB and protons in the pyridinium headgroup of CPB were observed under fast magic angle spinning (MAS) by (1)H-(1)H double quantum (DQ) MAS NMR and NOESY. This result suggested that CTAB and CPB co-exist in the pores without forming significant monocomponent domain structures. (1)H-(29)Si heteronuclear correlation (HETCOR) NMR showed that protons in the headgroups of CTAB are in closer proximity to the silica surface than those in the CPB headgroups. The structural information obtained in this investigation leads to better understanding of the mechanisms of self-assembly and their role in determining the structure and morphology of mesoporous materials.