Chronic shedding of a SARS-CoV-2 Alpha variant in wastewater.

BACKGROUND: Central Michigan University (CMU) participated in a state-wide SARS-CoV-2 wastewater monitoring program since 2021. Wastewater samples were collected from on-campus sites and nine off-campus wastewater treatment plants servicing small metropolitan and rural communities. SARS-CoV-2 genome copies were quantified using droplet digital PCR and results were reported to the health department. RESULTS: One rural, off-campus site consistently produced higher concentrations of SARS-CoV-2 genome copies. Samples from this site were sequenced and contained predominately a derivative of Alpha variant lineage B.1.1.7, detected from fall 2021 through summer 2023. Mutational analysis of reconstructed genes revealed divergence from the Alpha variant lineage sequence over time, including numerous mutations  in the Spike RBD and NTD. CONCLUSIONS: We discuss the possibility that a chronic SARS-CoV-2 infection accumulated adaptive mutations that promoted long-term infection. This study reveals that small wastewater treatment plants can enhance resolution of rare events and facilitate reconstruction of viral genomes due to the relative lack of contaminating sequences.

Spheroid architecture strongly enhances miR-221/222 expression and promotes oxidative phosphorylation in an ovarian cancer cell line through a mechanism that includes restriction of miR-9 expression.

BACKGROUND: Tumor cell spheroids are organized multicellular structures that form during the expansive growth of carcinoma cells. Spheroids formation is thought to contribute to metastasis by supporting growth and survival of mobile tumor cell populations. METHODS AND RESULTS: We investigated how spheroid architecture affects OXPHOS activity, microRNA expression, and intraperitoneal survival of an ovarian carcinoma cell line using high resolution respirometry, quantitative RT-PCR, and a rodent intraperitoneal growth model. Rates of oxidative phosphorylation/respiration per cell of cells growing as spheroids were nearly double those of a variant of the same cell type growing in suspension as loosely aggregated cells. Further, inhibition of spheroid formation by treatment with CDH2 (N-cadherin) siRNA reduced the rate of OXPHOS to that of the non-spheroid forming variant. Cells growing as spheroids showed greatly enhanced expression of miR-221/222, an oncomiR that targets multiple tumor suppressor genes and promotes invasion, and reduced expression of miR-9, which targets mitochondrial tRNA-modification enzymes and inhibits OXPHOS. Consistent with greater efficiency of ATP generation, tumor cells growing as spheroids injected into the nutrient-poor murine peritoneum survived longer than cells growing in suspension as loosely associated aggregates. CONCLUSIONS: The data indicate that growth in spheroid form enhances the OXPHOS activity of constituent tumor cells. In addition, spheroid architecture affects expression of microRNA genes involved in growth control and mitochondrial function. During the mobile phase of metastasis, when ovarian tumor cells disperse through nutrient-poor environments such as the peritoneum, enhanced OXPHOS activity afforded by spheroid architecture would enhance survival and metastatic potential.

Entecavir competitively inhibits deoxyguanosine and deoxyadenosine phosphorylation in isolated mitochondria and the perfused rat heart.

Deoxyguanosine kinase (dGK) is reported responsible for the phosphorylation of deoxyadenosine (dA) and deoxyguanosine (dG) in the mitochondrial purine salvage pathway. Antiviral nucleoside analogs known as nucleoside reverse transcriptase inhibitors (NRTIs) must be phosphorylated by host enzymes for the analog to become active. We address the possibility that NRTI purine analogs may be competitive inhibitors of dGK. From a group of such analogs, we demonstrate that entecavir (ETV) competitively inhibited the phosphorylation of dG and dA in rat mitochondria. Mitochondria from the brain, heart, kidney, and liver showed a marked preference for phosphorylation of dG over dA (10-30-fold) and ETV over dA (2.5-4-fold). We found that ETV inhibited the phosphorylation of dG with an IC50 of 15.3 ± 2.2 µM and that ETV and dG were both potent inhibitors of dA phosphorylation with IC50s of 0.034 ± 0.007 and 0.028 ± 0.006 µM, respectively. In addition, the phosphorylation of dG and ETV followed Michaelis-Menten kinetics and each competitively inhibited the phosphorylation of the other. We observed that the kinetics of dA phosphorylation were strikingly different from those of dG phosphorylation, with an exponentially lower affinity for dGK and no effect of dA on dG or ETV phosphorylation. Finally, in an isolated heart perfusion model, we demonstrated that dG, dA, and ETV were phosphorylated and dG phosphorylation was inhibited by ETV. Taken together, these data demonstrate that dGK is inhibited by ETV and that the primary role of dGK is in the phosphorylation of dG rather than dA.

Contributions of transient and sustained reward to memory formation.

Reward benefits to memory formation have been robustly linked to dopaminergic activity. Despite the established characterization of dopaminergic mechanisms as operating at multiple timescales, potentially supporting distinct functional outcomes, the temporal dynamics by which reward might modulate memory encoding are just beginning to be investigated. In the present study, we leveraged a mixed block/event experimental design to disentangle transient and sustained reward influences on task engagement and subsequent recognition memory in an adapted monetary-incentive-encoding (MIE) paradigm. Across three behavioral experiments, transient and sustained reward modulation of item and context memory was probed, at both 24-h and ~ 15-min retention intervals, to investigate the importance of overnight consolidation. In general, we observed that transient reward was associated with enhanced item memory encoding, while sustained reward modulated response speed but did not appear to benefit subsequent recognition accuracy. Notably, reward effects on item memory performance and response speed were somewhat inconsistent across the three experiments, with suggestions that RT speeding might also be related to time on task, and we did not observe reward modulation of context memory performance or amplification of reward benefits to memory by overnight consolidation. Taken together, the observed pattern of behavior is consistent with potentially distinct roles for transient and sustained reward in memory encoding and cognitive performance and suggests that further investigation of the temporal dynamics of dopaminergic contributions to memory formation will advance the understanding of motivated memory.

Changes in Nup62 content affect contact-induced differentiation of cultured myoblasts.

Differentiation of cultured skeletal myoblasts is induced by extrinsic signals that include reduction in ambient mitogen concentration and increased cell density. Using an established murine myoblast cell line (C2C12), we have found that experimental reduction of the nucleoporin p62 (Nup62) content of myoblasts enhances differentiation in high-mitogen medium, while forced expression of Nup62 inhibits density-induced differentiation. In contrast, differentiation of myoblasts induced by low-mitogen medium was unaffected by ectopic Nup62 expression. Further analyses suggested that Nup62 content affects density-induced myoblast differentiation through a mechanism involving activation of p38 MAP kinase. Nuclear pore complex (NPC) composition, in particular changes in NUP62 content, may be altered during viral infection, differentiation, and in neoplastic growth. The results support a functional role for changes in Nup62 composition in NPCs and density-induced myogenic differentiation, and suggest a link between loss of Nup62 content and induction of an intracellular stress signaling pathways.

A transfusion prescription template and other human factor interventions to improve balanced transfusion delivery in major haemorrhage due to trauma.

OBJECTIVES: The aim of this study is to improve practice in the management of major haemorrhage, particularly in red cell to plasma transfusion ratios. BACKGROUND: A review of the management of major haemorrhage in trauma in Newcastle Hospitals Trust in 2012-2013 showed good mortality outcomes but found that red cell : plasma transfusion ratios could be improved. Human factors techniques transferable from industry and the military were identified, and a package of interventions was implemented, including an intensive multidisciplinary team training programme and a new major haemorrhage prescription template. METHODS/MATERIALS: We reviewed the management of all 243 adult trauma patients admitted with major haemorrhage to the Emergency Department in the Newcastle Hospitals Trust in the 4-year period from April 2012. We analysed clinical details, blood components transfused and patient outcomes and used Trauma Audit and Research Network data to correlate with injury severity and predicted survival. RESULTS: Mean transfusion ratios of red cells to plasma improved from 1·5 : 1 and 1·6 : 1 in the first 2 years to 1·1 : 1 in the 2 years following implementation of the new measures. There was a statistically significant improvement in the delivery of a balanced transfusion, defined as a red cell : plasma ratio of <1·3 : 1 following the changes. CONCLUSION: Simple changes to procedures, specifically implementation of a new major haemorrhage prescription template and multidisciplinary team training, have resulted in marked improvement in the ratio of red cells to plasma transfused to trauma patients with major haemorrhage or requiring emergency blood. The package of changes could be easily replicated in other health-care settings.

Analysing the bioactive makeup of demineralised dentine matrix on bone marrow mesenchymal stem cells for enhanced bone repair.

Dentine matrix has proposed roles for directing mineralised tissue repair in dentine and bone; however, the range of bioactive components in dentine and specific biological effects on bone-derived mesenchymal stem cells (MSCs) in humans are less well understood. The aims of this study were to further elucidate the biological response of MSCs to demineralised dentine matrix (DDM) in enhancing wound repair responses and ascertain key contributing components. Dentine was obtained from human teeth and DDM proteins solubilised with ethylenediaminetetraacetic acid (EDTA). Bone marrow derived MSCs were commercially obtained. Cells with a more immature phenotype were then selected by preferential fibronectin adhesion (FN-BMMSCs) for use in subsequent in vitro assays. DDM at 10 µg/mL reduced cell expansion, attenuated apoptosis and was the minimal concentration capable of inducing osteoblastic differentiation. Enzyme-linked immunosorbent assay (ELISA) quantification of growth factors indicated physiological levels produced the above responses; transforming growth factor ß (TGF-ß1) was predominant (15.6 ng/mg DDM), with relatively lower concentrations of BMP-2, FGF, VEGF and PDGF (6.2-4.7 ng/mg DDM). Fractionation of growth factors from other DDM components by heparin affinity chromatography diminished osteogenic responses. Depletion of biglycan from DDM also attenuated osteogenic potency, which was partially rescued by the isolated biglycan. Decorin depletion from DDM had no influence on osteogenic potency. Collectively, these results demonstrate the potential of DDM for the delivery of physiological levels of growth factors for bone repair processes, and substantiate a role for biglycan as an additional adjuvant for driving osteogenic pathways.

Cattle ranching intensification in Brazil can reduce global greenhouse gas emissions by sparing land from deforestation.

This study examines whether policies to encourage cattle ranching intensification in Brazil can abate global greenhouse gas (GHG) emissions by sparing land from deforestation. We use an economic model of global land use to investigate, from 2010 to 2030, the global agricultural outcomes, land use changes, and GHG abatement resulting from two potential Brazilian policies: a tax on cattle from conventional pasture and a subsidy for cattle from semi-intensive pasture. We find that under either policy, Brazil could achieve considerable sparing of forests and abatement of GHGs, in line with its national policy targets. The land spared, particularly under the tax, is far less than proportional to the productivity increased. However, the tax, despite prompting less adoption of semi-intensive ranching, delivers slightly more forest sparing and GHG abatement than the subsidy. This difference is explained by increased deforestation associated with increased beef consumption under the subsidy and reduced deforestation associated with reduced beef consumption under the tax. Complementary policies to directly limit deforestation could help limit these effects. GHG abatement from either the tax or subsidy appears inexpensive but, over time, the tax would become cheaper than the subsidy. A revenue-neutral combination of the policies could be an element of a sustainable development strategy for Brazil and other emerging economies seeking to balance agricultural development and forest protection.

Fluorescence Angiography in Colorectal Resection.

BACKGROUND: Intraoperative laser fluorescence angiography is a relatively new tool that can be used by colorectal surgeons to ensure adequate perfusion to bowel that remains after resection. It has been used mostly to determine an appropriate point of transection of the proximal bowel, as well as to ensure perfusion after the anastomosis has been constructed. We propose a different use of the technology in complex cases to ensure the ability to safely transect a major vascular pedicle and to ensure that perfusion will remain adequate. OBJECTIVE: The purpose of this article is to describe a new use for fluorescence angiography technology. DESIGN: This is a technical note. SETTINGS: The work was conducted at a tertiary care military medical center. PATIENTS: Patients included individuals requiring oncologic colorectal resection where the status of 1 major vascular pedicle was unknown or impaired. MAIN OUTCOME MEASURES: We assessed perfusion after occlusion of a major vascular pedicle for the short term in hospital outcomes. RESULTS: Adequate studies were obtained, and perfusion was maintained in both patients. Oncologic resections were performed, and short-term outcomes were comparable with any individual undergoing these procedures. LIMITATIONS: This study was limited because it is early experience that was not performed in the setting of a scientific investigation. CONCLUSIONS: Application of intraoperative fluorescence angiography in this setting appears to be safe and may assist the surgeon in estimating reliable vascular perfusion in patients such as these who require oncologic colorectal resection.

Oral chronic graft-versus-host disease in Australia: clinical features and challenges in management.

Data from the Australasian Bone Marrow Transplant Recipient Registry show a steady increase in the number of allogeneic haemopoietic stem cell transplantations (HSCT) performed annually in Australia and New Zealand. In 2012, 629 allogeneic HSCT were performed. Allogeneic HSCT is associated with numerous potential complications, including chronic graft-versus-host disease (cGVHD). The oral cavity is one of the most frequent sites affected by cGvHD, often leading to significant disability and reduced quality of life. Management strategies are often complex, of variable efficacy and influenced by the availability of various therapeutic agents, access to compounding pharmacies and associated costs. This paper summarises the current status of allogeneic HSCT in Australia and New Zealand with a focus on oral cGvHD and the associated challenges in its management.

Separated response function ratios in exclusive, forward π(±) electroproduction.

The study of exclusive π(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σL(π-)/σL(π+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σT(π-)/σT(π+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6 GeV(2) at W=1.95 GeV, and Q(2)=2.45 GeV(2) at W=2.22 GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

Health economic impact of high-dose versus standard-dose cytarabine induction chemotherapy for acute myeloid leukaemia.

BACKGROUND: Induction chemotherapy for acute myeloid leukaemia (AML) is one of the most resource-intensive cancer therapies delivered in hospitals. AIMS: To assess the health resource impact of different chemotherapy approaches for AML commonly used in Australia. METHODS: A retrospective analysis was undertaken in 63 patients aged 18-55 years with AML given induction with either 7 + 3 (cytarabine 100 mg/m(2) days 1-7 and idarubicin 12 mg/m(2) days 1-3) or HiDAC-3 (high-dose cytarabine 3 g/m(2) twice daily days 1, 3, 5 and 7 and idarubicin 12 mg/m(2) days 1-3) chemotherapy. Average costs of hospitalisation, pathology, radiology, chemotherapy and ancillary drugs were calculated and compared with current Victorian casemix funding. Two consolidation approaches, HiDAC (cytarabine 3 g/m(2) twice daily days 1, 3, 5 and 7) × either three or four cycles (following 7 + 3) and IcE (idarubicin 12,mg/m(2) days 1-2, cytarabine 100 mg/m(2) × 5 days and etoposide 75 mg/m(2) × 5 days) × 2 cycles (following HiDAC-3) were modelled, using a policy of discharge following completion of chemotherapy with outpatient monitoring. RESULTS: The cost (in AUD) of induction was similar between 7 + 3 ($58,037) and HiDAC-3 ($56,902), with bed day costs accounting for 61-62% of the total expense. Blood bank costs ranked second, accounting for 15%. Accumulated costs for HiDAC consolidation were $44,289 for a three-cycle protocol and $59,052 for four cycles ($14,763 per cycle) versus $31,456 for two cycles of IcE consolidation ($15,728 per cycle). Overall, the classical 7 + 3 → HiDAC approach ($102,326/$117,089 for three or four consolidation cycles) incurs a greater cost than a HiDAC-3 → IcE × 2 approach ($88,358). For patients requiring complete hospitalisation until neutrophil recovery, the estimated costs of treatment will be even higher, ranging between $122,282 for HiDAC-3 → IcE × 2, $153,212 for 7 + 3 → HiDAC × 3 and $184,937 for 7 + 3 → HiDAC × 4. State-based casemix funding for non-complicated AML therapy is currently $74,013 for 7 + 3 → HiDAC × 4, $64,177 for 7 + 3 → HiDAC × 3 and $54,340 for HiDAC-3 → IcE × 2 based on outpatient recovery after consolidation chemotherapy. These calculations do not take into account additional resource implications associated with complications of consolidation chemotherapy or reinduction for treatment failure. CONCLUSION: Regimens minimising the total number of chemotherapy cycles may represent the most efficient use of limited health resources for the treatment of AML.

Fecal microbiomes of non-human primates in Western Uganda reveal species-specific communities largely resistant to habitat perturbation.

Primate gastrointestinal microbial communities are becoming increasingly appreciated for their relevance to comparative medicine and conservation, but the factors that structure primate "microbiomes" remain controversial. This study examined a community of primates in Kibale National Park, Uganda, to assess the relative importance of host species and location in structuring gastrointestinal microbiomes. Fecal samples were collected from primates in intact forest and from primates in highly disturbed forest fragments. People and livestock living nearby were also included, as was a geographically distant population of related red colobus in Kenya. A culture-free microbial community fingerprinting technique was used to analyze fecal microbiomes from 124 individual red colobus (Procolobus rufomitratus), 100 individual black-and-white colobus (Colobus guereza), 111 individual red-tailed guenons (Cercopithecus ascanius), 578 human volunteers, and 364 domestic animals, including cattle (Bos indicus and B. indicus × B. taurus crosses), goats (Caprus hircus), sheep (Ovis aries), and pigs (Sus scrofa). Microbiomes sorted strongly by host species, and forest fragmentation did not alter this pattern. Microbiomes of Kenyan red colobus sorted distinctly from microbiomes of Ugandan red colobus, but microbiomes from these two red colobus populations clustered more closely with each other than with any other species. Microbiomes from red colobus and black-and-white colobus were more differentiated than would be predicted by the phylogenetic relatedness of these two species, perhaps reflecting heretofore underappreciated differences in digestive physiology between the species. Within Kibale, social group membership influenced intra-specific variation among microbiomes. However, intra-specific variation was higher among primates in forest fragments than among primates in intact forest, perhaps reflecting the physical separation of fragments. These results suggest that, in this system, species-specific processes such as gastrointestinal physiology strongly structure microbial communities, and that primate microbiomes are relatively resistant to perturbation, even across large geographic distances or in the face of habitat disturbance.

Biomaterials in the treatment of anal fistula: hope or hype?

Anal fistula (AF) presents a chronic problem for patients and colorectal surgeons alike. Surgical treatment may result in impairment of continence and long-term risk of recurrence. Treatment options for AFs vary according to their location and complexity. The ideal approach should result in low recurrence rates and minimal impact on continence. New technical approaches involving biologically derived products such as biological mesh, fibrin glue, fistula plug, and stem cells have been applied in the treatment of AF to improve outcomes and decrease recurrence rates and the risk of fecal incontinence. In this review, we will highlight the current evidence and describe our personal experience with these novel approaches.

The mitochondrial genome of the deep-sea pyramid urchin Echinocrepis rostrata (Echinoidea: Holasteroida: Pourtalesiidae).

We present the mitochondrial genome of the deep-sea, epibenthic, irregular echinoid Echinocrepis rostrata, representing the first sequenced mitogenome of the order Holasteroida. The length of the complete E. rostrata mitochondrial genome is 15,716 base pairs, and its GC content is 34.87%. It contains 13 protein-coding genes, two rRNA genes, and 22 tRNA genes, whose order is identical to that of all other available echinoid mitogenomes. Phylogenetic analysis of available mitochondrial genomes, based on all coding loci, places E. rostrata as the sister group to spatangoids (heart urchins).

Atomic-scale origin of the enantiospecific decomposition of tartaric acid on chiral copper surfaces.

The origin of the enantiospecific decomposition of L- and D-tartaric acid on chiral Cu surfaces is elucidated on a structure-spread domed Cu(110) crystal by spatially resolved XPS and atomic-scale STM imaging. Extensive enantiospecific surface restructuring leads to the formation of surfaces vicinal to Cu(14,17,2) which are responsible for the enantiospecificity.

A remarkable new deep-sea nereidid (Annelida: Nereididae) with gills.

Nereidid polychaetes are well known from shallow marine habitats, but their diversity in the deep sea is poorly known. Here we describe an unusual new nereidid species found at methane seeps off the Pacific coast of Costa Rica. Specimens of Pectinereis strickrotti gen. nov., sp. nov. had been observed dating back to 2009 swimming just above the seafloor at ~1,000 m depth but were not successfully captured until 2018. Male epitokes were collected as well as a fragment of an infaunal female found in a pushcore sample. The specimens were all confirmed as the same species based on mitochondrial COI. Phylogenetic analyses, including one based on available whole mitochondrial genomes for nereidids, revealed no close relative, allowing for the placement of the new species in its own genus within the subfamily Nereidinae. This was supported by the unusual non-reproductive and epitokous morphology, including parapodial cirrostyles as pectinate gills, hooked aciculae, elfin-shoe-shaped ventral cirrophores, and elongate, fusiform dorsal ligules emerging sub-medially to enlarged cirrophores. Additionally, the gill-bearing subfamily Dendronereidinae, generally regarded as a junior synonym of Gymnonereidinae, is reviewed and it is here reinstated and as a monogeneric taxon.

Structural basis for Retriever-SNX17 assembly and endosomal sorting.

During endosomal recycling, Sorting Nexin 17 (SNX17) facilitates the transport of numerous membrane cargo proteins by tethering them to the Retriever complex. Despite its importance, the mechanisms underlying this interaction have remained elusive. Here, we report the structure of the Retriever-SNX17 complex determined using cryogenic electron microscopy (cryo-EM). Our structure reveals that the C-terminal tail of SNX17 engages with a highly conserved interface between the VPS35L and VPS26C subunits of Retriever. Through comprehensive biochemical, cellular, and proteomic analyses, we demonstrate that disrupting this interface impairs the Retriever-SNX17 interaction, subsequently affecting the recycling of SNX17-dependent cargos and altering the composition of the plasma membrane proteome. Intriguingly, we find that the SNX17-binding pocket on Retriever can be utilized by other ligands that share a consensus acidic C-terminal tail motif. By showing how SNX17 is linked to Retriever, our findings uncover a fundamental mechanism underlying endosomal trafficking of critical cargo proteins and reveal a mechanism by which Retriever can engage with other regulatory factors.

High-dose cytarabine (24 g/m2) in combination with idarubicin (HiDAC-3) results in high first-cycle response with limited gastrointestinal toxicity in adult acute myeloid leukaemia.

BACKGROUND/AIM: Although induction chemotherapy comprising high-dose cytarabine (HiDAC) in combination with idarubicin and etoposide or 'ICE' for adult acute myeloid leukaemia (AML) produces a complete remission rate of nearly 80%, gastrointestinal toxicity is significant. Omission of etoposide may produce similar clinical outcomes with potentially less gastrointestinal toxicity. METHODS: Fifty-three consecutive patients aged 15-60 with newly diagnosed AML, receiving high-dose cytarabine induction at the Alfred Hospital, Melbourne, were retrospectively analysed. Regimens included HiDAC-3 (idarubicin 12 mg/m(2) day 1-3, cytarabine 3 gm/m(2) bd day 1,3,5,7) or ICE (idarubicin 9 mg/m(2) day 1-3, cytarabine 3 g/m(2) bd day 1,3,5,7, etoposide 75 mg/m(2) day 1-7). Toxicity was assessed using Common Terminology Criteria for Adverse Events version 4.03. RESULTS: Thirty-one patients received HIDAC-3 and 22 patients received ICE induction. HiDAC-3 was better tolerated than ICE in terms of lower frequency of grade 3-4 nausea (0% vs 41%; P < 0.01), grade 3-4 diarrhoea (26% vs 55%; P = 0.05), lower rates of radiologically evident enterocolitis (6% vs 32%; P = 0.03) and less cumulative days of total parenteral nutrition use (1.2 vs 7.3 days; P < 0.01). Times to haematological recovery were similar between the two regimens. Thirty-day mortality was 0% for HiDAC-3 and 9% for ICE. Eighty-four per cent of HiDAC-3-treated patients achieved complete remission after the first cycle of therapy, compared with 77% with ICE. No differences in survival were evident between the two regimens. CONCLUSIONS: HiDAC-3 is a clinically effective induction regimen for adult AML, producing a high rate of first-cycle complete remission with less treatment-related gastrointestinal toxicity than ICE.