Supratherapeutic posaconazole concentrations associated with hyperlipidemia in a patient with HSCT.

Posaconazole is a potent, extended-spectrum triazole antifungal used for the treatment and prophylaxis of serious fungal infections. Previous reports have demonstrated hyperlipidemia resulted in significant changes in posaconazole pharmacokinetics and tissue distribution in rats. However, the effect of hyperlipidemia on the pharmacokinetics of posaconazole in patients has not yet been reported. We report a case of a 34-year-old woman who experienced a supratherapeutic posaconazole trough concentration (PTC) associated with hyperlipidemia after haploidentical hematopoietic stem cell transplantation (HSCT). The patient was admitted 13 months after HSCT for recurrent cough and sputum. She was treated with caspofungin due to developing invasive fungal infection of Candida tropicalis. After 10 days, caspofungin was discontinued due to the poor therapeutic efficacy and replaced with amphotericin B. Afterwards, the condition of the patient improved significantly and she was switched to daily oral posaconazole tablet. Therapeutic drug monitoring (TDM) of posaconazole showed a PTC was 3.2 mg/L. After discharge, she continued to receive posaconazole tablet as antifungal treatment. Two months later, laboratory tests at outpatient showed her blood lipid levels were significantly elevated and PTC was increased to 9.38 mg/L. Therefore, the posaconazole tablet was discontinued and she received lipid-lowering therapy. A few days later, the PTC was down to 5.22 mg/L. No medication errors and significant drug interactions were found. Hence, supratherapeutic PTC for this patient may be caused by hyperlipidemia which altered pharmacokinetics of posaconazole. Our findings highlight the need for close TDM in order to avoid supratherapeutic PTC if hyperlipidimia occurs during posaconazole use.

Developing Strategies to Improve the Efficacy of CAR-T Therapy for Acute Myeloid Leukemia.

OPINION STATEMENT: Acute myeloid leukemia (AML) is a fatal blood malignancy. With the development of immunotherapy, particularly chimeric antigen receptor T cells (CAR-T), the treatment of AML has undergone a significant change. Despite its advantages, CAR-T still faces a number of limitations and challenges while treating AML. Finding novel targets, altering the structure of CAR to increase efficacy while lowering side effects, and using double-target CAR and logic circuits are typical examples of key to answer these problems. With the advancement of gene editing technology, gene editing of tumor cells or normal cells to create therapeutic effects has grown in popularity. Additionally, the combination of multiple drugs is routinely used to address some of the obstacles and difficulties associated with CAR-T therapy. The review's primary goal was to summarize recent strategies and developments of CAR-T therapy for AML.

Reactive oxygen species mediated T lymphocyte abnormalities in an iron-overloaded mouse model and iron-overloaded patients with myelodysplastic syndromes.

The adverse effects of iron overload have raised more concerns as a growing number of studies reported its association with immune disorders. This study aimed to investigate alterations in the immune system by iron overload in patients with myelodysplastic syndrome (MDS) and an iron-overloaded mouse model. The peripheral blood from patients was harvested to test the effect of iron overload on the subsets of T lymphocytes, and the level of reactive oxygen species (ROS) was also evaluated. The data showed that iron-overloaded patients had a lower percentage of CD3+ T cells and disrupted T cell subsets, concomitant with higher ROS level in lymphocytes. In order to explore the mechanism, male C57Bl/6 mice were intraperitoneally injected with iron dextran at a dose of 250 mg/kg every 3 days for 4 weeks to establish an iron-overloaded mouse model and the blood of each mouse was collected for the analysis of the T lymphocyte subsets and T cell apoptosis. The results showed that iron overload could reduce the percentage of CD3+ T cells and the ratio of Th1/Th2 and Tc1/Tc2 but increase the percentage of regulatory T (Treg) cells and the ratio of CD4/CD8. We also found that iron overload induced the apoptosis of T lymphocytes and increased its ROS level. Furthermore, these effects could be partially recovered after treating with antioxidant N-acetyl-L-cysteine (NAC) or iron chelator deferasirox (DFX). Taken together, these observations indicated that iron overload could selectively affect peripheral T lymphocytes and induce an impaired cellular immunity by increasing ROS level.

Colony Stimulating Factor 3 Mutations and Myeloid Malignancies.

Granulocyte colony stimulating factor (G-CSF) plays a major role in the proliferation, differentiation, and activation of neutrophil cell line hematopoietic cells. G-CSF exert the function depending on its binding to colony-stimulating factor 3 receptor (CSF3R), a homo-dimer receptor located on the surface of effector cells. Some recent studies have demonstrated that CSF3R mutations play a significant role in many diseases. Some of the hematopoietic diseases, especially myeloid malignancies (e.g. chronic neutrophilic leukemia) are related to the presence of various CSF3R mutations, which leads to abnormal G-CSF signal pathways. Also, the downstream kinases can be the treatment targets for these diseases. This review summarizes CSF3R mutations, mechanisms of mutations, and their contributions to the myeloid malignancies, with an attempt to further reveal the pathogenesis of myeloid malignancies, inform the diagnosis and clinical treatment of the myeloid malignancies, and provide clues for the research and development of new molecular target drugs.

Evaluating omadacycline dosing regimens against drug-resistant pathogens including Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae in adults: a pharmacokinetic/pharmacodynamic analysis using Monte Carlo simulation.

The objective of this study was to evaluate the efficacy of various dosing regimens of omadacycline against main drug-resistant pathogens in the treatment of acute bacterial skin and skin structure infections (ABSSSI) and community-acquired bacterial pneumonia (CABP). Monte Carlo simulations were conducted using pharmacokinetic parameters and pharmacodynamic data to calculate cumulative fractions of response (CFRs) in terms of drug area under the concentration curve/minimum inhibition concentration targets.CFR ≥ 90% was considered optimal for a dosage regimen. CFR of any approved oral/intravenous regimen with loading-dose was ≥ 90% against methicillin-resistant Staphylococcus aureus (MRSA) for ABSSSI and penicillin-resistant Streptococcus pneumonia, tetracycline-resistant Streptococcus pneumonia, MRSA and ß-lactamase positive Haemophilus influenzae for CABP. In conclusion, approved oral/intravenous loading and maintenance doses of omadacycline showed enough efficacy in the treatment of ABSSI and CABP caused by the main drug-resistant pathogens.

The novel HLA-C*12:02:52 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-C*12:02:52 differs from HLA-C*12:02:02:01 by one nucleotide in exon 1.

[Epidemiology of invasive fungal disease in patients with hematological diseases].

OBJECTIVE: To explore the epidemiological profiles of invasive fungal disease (IFD) in hospitalized patients with hematological diseases during 2007-2012. METHODS: A total of 419 IFD patients with hematological diseases from January 2007 to December 2012 were reviewed. All of them were analyzed with regards to diagnostic levels, infection sites and various related factors. RESULTS: (1) A total of 233 cases (55.61%) were preliminarily identified as IFD, 140 cases (33.41%) had a clinical diagnosis and 46 cases (10.98%) were confirmed cases of IFD. (2) Among 46 confirmed cases of IFD, there were agranulocytosis (n = 43) and aspergillosis infection (n = 36). (3) Respiratory tract was the most frequent infection site in all IFD patients (85.20%) . (4) And chemotherapy-induced agranulocytosis was a major reason for IFD patients with hematological diseases. The number of IFD patients without chemotherapy had a rising trend. (5) The age group of IFD was during 41-60 years old. (6) All of them stayed on antibiotic therapy at the diagnosis of IFD. The numbers of antibiotics were two(205 cases, 48.93%) and three(179 cases, 42.72%). (7) The peak incidence of IFD was recorded in January, July and December. And June was another lower peak. CONCLUSIONS: Agranulocytosis is the main reason for IFD patients with hematological disease. The data is important and valuable for the early diagnosis and therapy of IFD patients with hematological disease.

[Reactive oxygen species mediate the injury and deficient hematopoietic supportive capacity of umbilical cord derived mesenchymal stem cells induced by iron overload].

OBJECTIVE: To explore the effects of iron overload on umbilical cord derived mesenchymal stem cells (UC-MSC) and elucidate the involvement of reactive oxygen species (ROS) in this process. METHODS: The iron overload model of MSC was established by in vitro addition of ferric ammonium citrate (FAC) into culture medium. Cell proliferation and apoptosis were determined by Annexin V/PI double staining and population doubling time (DT) respectively. Co-culture system was used to assess the hematopoietic support capacity of UC-MSC in different groups. Thereafter the ROS level was detected with fluorescent probe 2', 7'-dichlorofluorescin diacetate (DCFH-DA). And the ROS related signaling factors of p-p38MAPK, p38 MAPK, P53 were measured by Western blot. RESULTS: (1) The DT of UC-MSC in iron overload group was significantly longer than that of control ((24.43 ± 2.72) h vs (16.03 ± 2.31) h, P < 0.05). But the difference was insignificant after two passages (P > 0.05). (2) Apoptosis in iron overload group was higher than that of control (12.75% ± 0.32% vs 3.63% ± 0.80%, P < 0.05). (3) The colony forming capacity of mononuclear cell (MNC) co-cultured with UC-MSC of iron overload group for 1/2 weeks significantly decreased. (4) The ROS level of UC-MSC with iron overload was higher than that of control in time and concentration-dependent fashions and it peaked at 400 µmol/L of FAC for 12 h (1499 ± 86 vs 548 ± 97, P < 0.05). (5) The expressions of p-p38MAPK and P53 increased in response to FAC compared with control. But such an effect was partially inhibited after the use of antioxidants. CONCLUSIONS: Iron overload may impair the proliferation, survival and hematopoiesis supportive function of UC-MSC by enhancing the generation of ROS. And ROS stimulates the signaling pathways of p-p38MAPK and P53.

[Effects and mechanism on anti-leukemic activity of cytokine-induced killer cells with an endogenous expression of interleukin-21].

OBJECTIVE: To explore the effects and mechanism on anti-leukemic activity of cytokine inducing killer (CIK) cells with an endogenous expression of interleukin-21 (IL-21). METHODS: Mononuclear cells were isolated from peripheral blood and cultured with cytokines to generate CIK cells. IL-21 lentiviral vector was constructed and used to transfect 293T cells. Then the culture supernatant with virus infected CIK cells was identified. Proliferation of CIK cells and their cytotoxic activity against K562 cells were measured by methyl thiazolyl tetrazolium (MTT). The expressions of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), tumor necrosis factor-ß (TNF-ß), perforin, granzyme A, granzyme B, FasL and NKG2D mRNA were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Immunophenotypes of CIK cells, IL-21 receptor (IL-21R) and FasL on the surface of CIK cells, intra-cellular perforin and granzyme B of CIK cells were measured by flow cytometry. And the concentrations of IFN-γ and TNF-α in cultured supernatant were measured by enzyme immunoassay. RESULTS: By restriction enzyme digestion and sequencing, IL-21 lentiviral vector was identified, after transfecting virus supernatant into CIK cells, the expression of IL-21 was detected in CIK cells. Compared to control, (1) the total number of cells remained unchanged, but the proportion of cells expressing CD3(+)/CD56(+) phenotype increased from 16.95% ± 4.70% to 24.60% ± 2.10%. (2) Cytotoxic activity against K562 cells by CIK cells increased from 23.3% ± 2.8% to 58.4% ± 8.3% and stayed at 61.2% ± 6.2% after 5 days. It was stronger and longer compared to the exogenous effect of IL-21 (from 22.8% ± 2.8% to 44.6% ± 8.3%). (3) The expression of IL-21R increased around 2 folds. (4) The mRNA expressions of IFN-γ and TNF-α increased almost 1.5 folds, perforin, granzyme B, FasL rose almost 2 folds, the expressions of granzyme A, TNF-ß and NKG2D were similar with those of controls. (5) Detected by flow cytometry, the expression of FasL of CIK cells was higher than that of control (0.56% ± 0.37% vs 0.06% ± 0.02%), the expression of perforin increased from 12.23% ± 2.35% to 25.86% ± 6.13%, the expression of granzyme B rose from 14.56% ± 1.36% to 37.58% ± 2.30%, the concentration of IFN-γ in culture supernatant spiked from (23.2 ± 5.6) to (55.3 ± 3.5) ng/L and TNF-α jumped from (5.6 ± 0.6) to (15.6 ± 0.6) µg/L. CONCLUSIONS: CIK cells with an endogenous expression of IL-21 have stronger anti-leukemic activity through an up-regulation of IL-21R, perforin, granzyme B, FasL, IFN-γ and TNF-α. Thus IL-21 may potentially enhance the anti-leukemic immunotherapy.

[Establishment of an mouse model of iron-overload and its impact on bone marrow hematopoiesis].

OBJECTIVE: To establish a mouse model of iron overload by intraperitoneal injection of iron dextran and investigate the impact of iron overload on bone marrow hematopoiesis. METHODS: A total of 40 C57BL/6 mice were divided into control group, low-dose iron group (12.5 mg/ml), middle-dose iron group (25 mg/ml), and high-dose iron group (50 mg/ml). The control group received normal saline (0.2 ml), and the rest were injected with intraperitoneal iron dextran every three days for six weeks. Iron overload was confirmed by observing the bone marrow, hepatic, and splenic iron deposits and the bone marrow labile iron pool. In addition, peripheral blood and bone marrow mononuclear cells were counted and the hematopoietic function was assessed. RESULTS: Iron deposits in bone marrow, liver, and spleen were markedly increased in the mouse models. Bone marrow iron was deposited mostly within the matrix with no significant difference in expression of labile iron pool.Compared with control group, the ability of hematopoietic colony-forming in three interventional groups were decreased significantly (P<0.05). Bone marrow mononuclear cells counts showed no significant difference. The amounts of peripheral blood cells (white blood cells, red blood cells, platelets, and hemoglobin) in different iron groups showed no significant difference among these groups;although the platelets were decreased slightly in low-dose iron group [(780.7±39.60)×10(9)/L], middle dose iron group [(676.2±21.43)×10(9)/L], and high-dose iron group [(587.3±19.67)×10(9)/L] when compared with the control group [(926.0±28.23)×10(9)/L], there was no significant difference(P>0.05). CONCLUSIONS: The iron-overloaded mouse model was successfully established by intraperitoneal administration of iron dextran. Iron overload can damage the hepatic, splenic, and bone marrow hematopoietic function, although no significant difference was observed in peripheral blood count.

[Effect and mechanism of iron-catalyzed oxidative stress on mesenchymal stem cells].

OBJECTIVE: To explore effect of iron overload on the proliferation and apoptosis of mesenchymal stem cell(MSCs) and the possible mechanism. METHODS: Iron overload model of MSCs was established by adding ferric ammonium citrae (FAC) into the culture medium at different concentrations (100, 200, 400 Μmol/L) and incubated for different lengths of time (12, 24, 48 h). The levels of labile iron pool (LIP) and reactive oxygen species (ROS) were measured to confirm oxidative stress state in the model. Changes in cell proliferation and apoptosis after iron overload were measured through population double time(DT)and annexin V-PI assay. Finally, the expressions of phosphorylated p38 mitogen activated protein kinase (P-p38MAPK), p38MAPK, protein kinase B (AKT), and p53 were determined through Western blot analysis to investigate which ROS-mediated signaling pathway was involved in this process. RESULTS: The LIP level of MSCs was significantly increased by FAC treatment at 400 Μmol/L (mean fluorescence intensity 482.49±20.96 vs. 303.88±23.37, P<0.05). The level of intracellular ROS was positively correlated with the concentration of FAC and reached a peak level when cultured with 400 Μmol/L FAC (P<0.05).After treatment with 400 Μmol/L FAC at different time points (12 h, 24 h, and 48 h), the DT of MSCs was (1.47± 0.11) d, (1.80±0.13) d, and (2.04±0.14) d, respectively, which was signifcantly longer than that of the control, which was(1.20±0.05)d (P<0.05).The apoptosis rate was also significantly higher in iron overload group[(3.51±1.17)% vs.(0.66±0.62)%, P<0.05]with consequent increase in the expressions of P-p38MAPK, p38MAPK, and p53 proteins in iron overload group, while no significant difference was found in the expression of AKT. CONCLUSION: Iron overload can inhibit the proliferation of MSCs and induce their apoptosis through the generation of ROS, which is probably due to the stimulation of p38MAPK- p53 signaling pathway.

Assessment of micafungin dosage regimens against Candida spp. in pediatric patients undergoing hematopoietic stem cell transplantation: a pharmacokinetic/pharmacodynamic analysis using Monte Carlo simulation.

The objective of this study was to evaluate the efficacy of various micafungin dosing regimens against Candida spp. in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). Monte Carlo simulations were conducted using pharmacokinetic (PK) parameters and pharmacodynamic (PD) data to determine the probabilities of target attainment and cumulative fractions of response in terms of area under the concentration curve/minimum inhibition concentration targets of micafungin. Current standard clinical micafungin dosing regimens of 1 and 2 mg/kg/day were appropriate for the prevention and treatment of Candida glabrata infection in pediatric patients undergoing HSCT, respectively. Moreover, the high-dose prophylactic dosage (2 mg/kg/day) and therapeutic dosage (4 mg/kg/day) should be the preferred option to optimize efficacy against Candida albicans. However, none of the simulated regimens was effective against Candida parapsilosis in pediatric HSCT patients. These PK/PD-based simulations rationalize and optimize the micafungin dosing regimens against Candida spp. in pediatric patients undergoing HSCT.

Ileus induced by the combination of vinca alkaloids and posaconazole in a patient with acute lymphoblastic leukemia: a case report and literature review.

Vinca alkaloid (VA)-induced ileus, a rare but severe autonomic neuropathy, can be enhanced by concomitant use of antifungal triazole agents. We herein present a case of VA-induced ileus in a 17-year-old girl who was diagnosed with B-cell acute lymphoblastic leukemia. On day 1, the patient received cyclophosphamide, vincristine, and methylprednisolone. On day 2, she began treatment with posaconazole oral suspension at 200 mg three times daily for prophylaxis against invasive fungal infection. On day 5, she began induction therapy consisting of vindesine, methylprednisolone, daunorubicin, and cyclophosphamide. The patient developed severe abdominal pain with marked constipation on day 11 and was diagnosed with incomplete ileus. After switching the antifungal agent to micafungin, performing gastrointestinal decompression, administering parenteral nutrition, and omitting the fourth dose of vindesine, the ileus symptoms were relieved. This case emphasizes the potential interaction between VAs and posaconazole. We also herein present a review of the literature on ileus caused by the combination of VAs and antifungal triazole agents. In clinical practice, physicians and pharmacists should be aware of the possibility of ileus caused by the use of VAs in combination with posaconazole. It is important to reduce complications during chemotherapy to improve patients' prognosis.

[Effect of oxidative stress on bone marrow mesenchymal stem cells].

Bone marrow mesenchymal stem cells (MSCs) are somatic stem cells that can differentiate into progenies of multiple lineages. They play an important role in hematopoiesis and stem cell therapy due to their multi-lineage potentials and immunomodulatory properties. Oxidative stress is a disturbed redox state caused by accumulation of reactive oxygen species. It can induce the senescence and apoptosis of MSCs via phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) and p53 pathways, and inhibit the proliferation and differentiation of MSCs through apurinic/apyrimidinic endonuclease/redox factor 1 (APE/REF-1) and extracellular signal-regulated kinase (ERK) pathways. Furthermore, using anti-stress medication and hypoxic preconditioning, the functions of MSCs can be further enhanced. Accordingly, further studies on the effect of oxidative stress on MSCs and its signaling pathways may be meaningful for the treatment of hematologic diseases and for improving stem cell therapy.

[Effects of oxidative stress on hematopoiesis of hematopoietic stem and progenitor cells with iron overload].

OBJECTIVE: To establish a model of hematopoietic stem and progenitor cells with iron overload derived from umbilical cord blood (UCB) cells and explore the effects of reactive oxygen species (ROS) on the hematopoiesis of hematopoietic stem and progenitor cells with iron overload. METHODS: The model was established by adding different concentrations (50, 100, 200, 400 µmol/L)of ferric citrate (FAC) into mononuclear cells from UCB and culturing for different times (6, 12, 24 h). The UCB cells were divided into 4 groups: control group, group FAC, group FAC+N-acetyl-L-cysteine (NAC) and group FAC+ L-Glutathione (GSH). Then the changes of ROS, labile iron pool (LIP), apoptosis, the capacity of hematopoietic colony forming (CFU-E, BFU-E, CFU-GM, CFU-mix) and the percentage and the numbers of CD34(+), CD33(+), GlyA(+) cells were detected. And the changes of these indices were tested after the treatment of iron overload UCB with antioxidants (NAC and GSH). RESULTS: UCB cells were cultured with the addition of FAC at different concentrations for different times. The level of total ROS increased in time and concentration-dependent manners. The intracellular level of ROS peaked when cultured at 200 µmol/L of FAC for 24 hours. Cells were treated with antioxidants NAC or GSH after cultured with 200 µmol/L FAC for 24 hours. Then the ROS levels of total cells, myeloid cells and erythroid cells decreased markedly versus normal controls. The LIP of total cells, myeloid cells and erythroid cells increased markedly when cells were cultured at 200 µmol/L of FAC for 24 hours versus normal controls (P < 0.05). NAC and GSH had no effect on the level of LIP. The apoptotic rates of FAC-treated cells [(20.90 ± 3.45)%] increased significantly versus normal controls [(9.20 ± 1.29)%] (P < 0.05). The capacity of hematopoietic colony forming in FAC treated cells decreased markedly versus normal controls. The percentage and numbers of CD34(+), CD33(+), GlyA(+) cells of FAC-treated cells also decreased significantly versus normal controls (P < 0.05). And these changes could be recovered by the addition of NAC or GSH. CONCLUSION: Oxidative stress plays an important role in the injuries of hematopoiesis of hematopoietic stem and progenitor cells with iron overload by inducing the generation of ROS. These findings may help us find a specific target and improve the therapeutic efficacy of ineffective hematopoiesis in patients with iron overload.

Noninvasive tools based on immune biomarkers for the diagnosis of central nervous system graft-vs-host disease: Two case reports and a review of the literature.

BACKGROUND: Central nervous system graft-vs-host disease (CNS-GVHD) is a rare cause of CNS disorders after allogeneic hematopoietic stem cell transplantation. Currently, establishing a diagnosis of CNS-GVHD is challenging because the diagnostic criteria and diagnostic methods are not well defined and many confounding factors need to be ruled out. CASE SUMMARY: Here, we present two patients with CNS-GVHD. Both patients with a history of acute GVHD or chronic GVHD developed neurological symptoms that could not be explained by other causes, and had abnormal cerebrospinal fluid (CSF) studies as determined by CSF and blood immune biomarker examinations, suggestive of suspected CNS-GVHD. Due to the lack of specific magnetic resonance imaging abnormalities and the rapid clinical deterioration of the patients, we did not attempt to perform a brain biopsy, but prompted the initiation of empirical immunosuppressive therapy. In view of the rapid and favorable response to local and systematic immunosuppressive treatment and the aforementioned neurologic manifestations together with CSF abnormalities and other negative findings, a final diagnosis of CNS-GVHD was made. CONCLUSION: CSF and blood immune biomarker examinations facilitated the diagnosis of CNS-GVHD, which are particularly suitable for patients who are critically ill and require urgent treatment and for those who are unsuitable for invasive diagnostic procedures.

[Effect and Involved Mechanism of RSL3-induced Ferroptosis in Acute Leukemia Cells MOLM13 and Drug-resistant Cell Lines].

OBJECTIVE: To investigate the effect and involved mechanism of RSL3 on ferroptosis action in acute leukemia cells MOLM13 and its drug-resistant cells. METHODS: After MOLM13 treated with RSL3, CCK-8 assay was performed to detect cell viability, flow cytometry was used to detect the reactive oxygen species (ROS) level of the cells, RT-qPCR and Western blot were used to detect the expression of glutathione peroxidase 4 (GPX4). After MOLM13/IDA and MOLM13/Ara-C, the drug-resistant cell lines were constructed, the ferroptosis induced by RSL3 was observed. Bone marrow samples were collected from patients with acute monocytic leukemia. RT-qPCR and Western blot were performed to detect the expression of related genes and proteins involved in ferroptosis pathway. RESULTS: RSL3 significantly inhibited the cell viability of MOLM13 and increased the intracellular ROS level, which were partially reversed by ferrostatin-1. The mRNA and protein expression of GPX4 decreased in MOLM13 treated with RSL3. RSL3 inhibited the viability of MOLM13/IDA and MOLM13/Ara-C cells more strongly than that of non-drug resistant cells, also increased the intracellular ROS level . The cytotoxic effects were partially reversed by ferrostatin-1. The mRNA and protein expressions of GPX4 in MOLM13/IDA and MOLM13/Ara-C cells were higher than those in non-drug resistant cells. The mRNA and protein levels of GPX4 in bone marrow of relapsed/refractory acute mononuclear leukemia patients were higher than those of ordinary acute mononuclear leukemia patients. CONCLUSION: RSL3 can induce non-drug resistant cells MOLM13 ferroptosis by inhibiting GPX4 activity. MOLM13/IDA and MOLM13/Ara-C are more sensitive to RSL3 compared with non-drug resistant cells MOLM13, which may be caused by the differences in GPX4 expression. The expressions of GPX4 mRNA and protein in relapsed/refractory acute mononuclear leukemia are higher than those in ordinary acute mononuclear leukemia.

Evaluating posaconazole dosing regimens of the different formulations against Aspergillus spp. in adults: a pharmacokinetic/pharmacodynamic analysis using Monte Carlo simulation.

The objective of this study was to evaluate the efficacy of various posaconazole dosing regimens of the different formulations against Aspergillus spp. in adults. Monte Carlo simulations were conducted using pharmacokinetic (PK) parameters and pharmacodynamic (PD) data to determine the probability of target attainment (PTA) and cumulative fraction of response (CFR) in terms of area under the concentration-time curve/minimum inhibition concentration (AUC/MIC) targets of posaconazole. According to the results of the PTA analysis, currently recommended clinical dosing regimens of the delayed-release tablet and intravenous (i.v.) solution were appropriate in prophylaxis against Aspergillus spp. with MICs ≤ 0.125 µg/mL. However, only high-dose regimens of the delayed-release tablet could achieve the target PTA in the treatment against Aspergillus spp. at an MIC of 0.125 µg/mL. Furthermore, the CFR was calculated for each dosing regimen. For the oral suspension, none of the simulated dosing regimens was effective against Aspergillus spp. For the delayed-release tablet and i.v. solution, the recommended dosing regimens were effective for prophylaxis of invasive fungal infections by four Aspergillus spp. (Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans and Aspergillus terreus). However, these recommended dosing regimens were only effective for the treatment of A. terreus infection. Therefore, the high-dose regimen (200 mg oral every 12 h) of the delayed-release tablet should be recommended to achieve optimal therapeutic efficacy against four Aspergillus spp. (A. flavus, A. fumigatus, A. nidulans and A. terreus). These PK/PD-based simulations rationalise and optimise the dosing regimens of the different posaconazole formulations against Aspergillus spp. in adults.

Pharmacokinetic/Pharmacodynamic Analysis of Daptomycin Against Staphylococcus aureus and Enterococcus faecium in Pediatric Patients by Monte Carlo Simulation.

The objective of this study was to evaluate the efficacy of various daptomycin dosing regimens against Staphylococcus aureus and Enterococcus faecium in pediatric patients with proven/suspected gram-positive infection. Monte Carlo simulations (MCSs) were conducted using pharmacokinetic (PK) parameters and pharmacodynamic (PD) data to determine the probabilities of target attainment and cumulative fractions of response in terms of area under the concentration curve/minimum inhibition concentration (MIC) targets of daptomycin. According to the results of the MCSs, currently approved pediatric dosage regimens were sufficient against Staphylococcus aureus with MIC ≤ 0.5 µg/mL for all pediatric patients, but poor when MIC ≥ 1 µg/mL except for adolescents (12-17 years) who need a dosage of ≥10 mg/kg/day at MIC = 1 µg/mL. For Enterococcus faecium with MIC ≤ 4 µg/mL, the recommended dosage of 8-12 mg/kg/day in adults was enough for adolescents, but not subjected to younger pediatric patients. Furthermore, based on MIC distributions obtained from the European Committee on Antimicrobial Susceptibility Testing, the approved high-dose regimen should be recommended for infants aged 3-12 months, children (2-11 years), and adolescents to achieve better clinical efficacy against methicillin-resistant Staphylococcus aureus. In addition, the dosage of 8-12 mg/kg/day was powerful against Enterococcus faecium for adolescents; however, only the highest dosage of 12 mg/kg/day was effective for infants aged 3-12 months and children. All the simulated regimens were not optimal for infants aged 13-24 months. These PK/PD-based simulations rationalize and optimize the dosage regimens of daptomycin against Staphylococcus aureus and Enterococcus faecium in pediatric patients.

[Clinical Effectiveness of Decitabine Combined with Reduced FLAG Regimen in the Treatment of Senile Patients with High-Risk Acute Myeloid Leukemia].

OBJECTIVE: To explore the efficacy and adverse reactions of decitabine combined with reduction FLAG regimen on the senile patients with high-risk AML. METHODS: 12 senile patients with high-risk AML received decitabine combined with reduced FLAG regimen (decitabine 20 mg/m2, intravenous drip, qd, d 1-5; fludarabine 30 mg/m2, intravenous drip lasts 30 min, qd, d 3-6; Ara-C 1 g/m2, intravenous drip, qd, d 3-6; and G-CSF 300 µg/d, subcu- taneous injection, d 2 to neutrophils reached the lowest return to＞1.0×109/L) in our study. The efficacy and adverse reactions of this regimen were analyzed. RESULTS: 9 patients achieved complete remission(CR) after one course of decitabine combined with reduced FLAG regimen, 2 patients achieved partial remission (PR) and 1 patient reached a stable disease (SD). The overall response rate was 92%. The median follow-up period was 7.4 months ranged from 3 to 12 months. The median survival time for all patients was 6.4 months. The main treatment-related toxicities were myelosuppression and infection due to neutropenia. Severe non-hematologic toxicities were not observed in these patients, and there was no treatment-related mortality. CONCLUSION: Decitabine combined with reduced FLAG regimen has a definite clinical efficacy in the treatment of senile patients with high-risk AML. This regimen, as induction remission regimen, can effectively improve the CR rate and reduce the adverse reactions. Therefore, it may be used as one of the preferred induction remission regimen to treat the senile patients with high-risk AML.